Search

Bio-based renewable resources have emerged as strong contenders to produce fuels and chemicals via carbon–neutral and eco-friendly methods. In particular, 2,5 furandicarboxylic acid (FDCA) which is listed among the top 12 platform molecules, can be used to produce bio-based polymer as an alternative to polyethylene terephthalate (PET). Notably, FDCA can be produced from an array of biorenewable resources using catalytic materials. However, biomass-derived 5-hydroxymethylfurfural (HMF) remains the primary feedstock to produce FDCA. Thus, the current review focuses on the recent advances in FDCA application and production via catalytic routes, particularly from HMF and other biorenewable feedstocks. Accordingly, the effect of different noble metal and noble metal-free catalytic materials on feedstock conversion and FDCA yield has been discussed. Moreover, the effect of operating conditions such as solvent, bases, oxygen sources, temperature and pressure has been discussed.

5-hydroxymethylfurfural (HMF) is formed by reducing sugars in honey in acidic environments by the Maillard reaction and is known as a carcinogenic, mutagenic and genotoxic compound. The aim of this study is to investigate the toxic HMF content of unbranded flower honey samples sold under the sun under inappropriate conditions and unsupervised on the highway sides and to make an evaluation in terms of food safety. The quality of the analysis results was guaranteed by participating in an international proficiency test. Analysis was performed on a High-Performance Liquid Chromatography (HPLC) device with Diode Array Detector (DAD) and Refractive Index (RI) detectors- The HMF levels of 5 honey samples were determined to exceed the legal limit (40 mg kg-1). It is revealed by the current study that the honey sold on the roadside is not safe in terms of toxic HMF. In addition, 5 samples were not found to comply with the regulation in terms of glucose + fructose content and 2 samples in terms of fructose/glucose ratio. Thus, it has also been determined that these honeys are not reliable in terms of purity.

Building blocks with amine functionality are crucial in the chemical industry. Biocatalytic syntheses and chemicals derived from renewable resources are increasingly desired to achieve sustainable production of these amines. As a result, renewable materials such as furfurals, especially furfurylamines like 5-(hydroxymethyl)furfurylamine (HMFA) and 2,5-di(aminomethyl)furan (DAF), are gaining increasing attention. In this study, we identified four different amine transaminases (ATAs) that catalyze the reductive amination of 5-(hydroxymethyl)furfural (HMF) and 2,5-diformylfuran (DFF). We successfully immobilized these ATAs on glutaraldehyde-functionalized amine beads using multiple binding and on amine beads by site-selective binding of the unique Cα-formylglycine within an aldehyde tag. All immobilized ATAs were efficiently reused in five repetitive cycles of reductive amination of HMF with alanine as co-substrate, while the ATA from Silicibacter pomeroyi (ATA-Spo) also exhibited high stability for reuse when isopropylamine was used as an amine donor. Additionally, immobilized ATA-Spo yielded high conversion in the batch syntheses of HMFA and DAF using alanine (87% and 87%, respectively) or isopropylamine (99% and 98%, respectively) as amine donors. We further demonstrated that ATA-Spo was effective for the reductive amination of HMF with alanine or isopropylamine in continuous-flow catalysis with high conversion up to 12 days (48% and 41%, respectively).

A series of Nb2O5 solid catalysts have been prepared to be used for the catalytic dehydration of glucose and sugars from algae Chlorella sp. into added value furans. The glucose transformation gave rise to 5-hydroxymethylfurfural (5-HMF). Chlorella sp. was used in the same catalytic conditions to be valorised to furans. By preliminary studies we concluded that the algae aqueous suspension needed a previous treatment in the presence of SiO2 pellets to liberate the carbohydrates that in the catalytic reaction in the presence of Nb2O5 materials gave rise 5-HMF and furfural. The best operative conditions and Nb2O5 catalysts were individuated. The most performant Nb2O5 catalyst also showed an excellent reusability without deactivation. The selectivity to furans was related to the acidity of the solid used as catalyst.

The ability of additives to reduce the formation of acrylamide in simulated sugar cane syrups was investigated. Organic acids, B vitamins, and inorganic salts were added individually and in combination to simulated thickened cane juice, and the mixtures were heated at 120 ◦C for 30 min. Calcium chloride (1%), citric acid (0.1%), and vitamin B3 (0.1%) were the most effective individual additives from each chemical family. The effects of CaCl2 (0–1%), citric acid (0–0.125%), and vitamin B3 (0–0.1125%), when added in combination, on the concentrations of acrylamide and hydroxymethylfurfural (HMF) were studied using a Box–Behnken design. Combinations of all three additives lowered the acrylamide production, but only the combination of citric acid and vitamin B3 had a significant synergistic effect. However, all these additives stimulated the production of HMF, and no significant interactive effect between pairs of additives on HMF production was observed. Calcium chloride stimulated the formation of HMF most strongly. These results indicate that certain combinations of these additives effectively reduce acrylamide formation, but they also lead to an increase in the formation of HMF in sugar syrup. This research was funded by (1) The Office of the Ministry of Higher Education, Science, Research and Innovation of the Government of Thailand, the Thailand Science Research and Innovation Project administered by the Kasetsart University Reinventing University Program 2021 (Grant Number RUP1/Con(1.3)-CASAF08); (2) Research and Researchers for Industries (RRI) of the Thailand Science Research and Innovation Office and the Mitr Phol Innovation & Research Center (Grant Number PHD60I0033); (3) LC-MS/MS equipment at UMH has been financed by Grant EQC2018-004170-P funded by MCIN/AEI/10.13039/501100011033 and by ERDF A way of making Europe and (4) the consumables at UMH have been financed by AICO/2021/326, Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital, Generalitat Valenciana. info:eu-repo/semantics/publishedVersion

Abstract In this work, a deep eutectic solvent (DES) composed of choline chloride (ChCl) and ethylene glycol (EG) was prepared and applied for the conversion of fructose to 5-hydroxymethylfurfural (HMF), catalyzed by HCl in both laboratory batch reactors and continuous flow microreactors. The effects of reaction temperature, batch time, catalyst loading and molar ratio of ChCl to EG on the fructose conversion and HMF yield were first investigated in the monophasic batch system of ChCl/EG DES. To inhibit HMF-involved side reactions (e.g., its polymerization to humins), methyl isobutyl ketone (MIBK) was used as the extraction agent to form a biphasic system with DES in batch reactors. As a result, the maximum HMF yield could be enhanced at an MIBK to DES volume ratio of 3:1, e.g., increased from 48% in the monophasic DES (with a molar ratio ChCl to EG at 1:3) to 63% in the biphasic system at 80°C and 5 mol% of HCl loading. Based on the optimized results in batch reactors, biphasic experiments were conducted in capillary microreactors under slug flow operation, where a maximum HMF yield of ca. 61% could be obtained in 13 min, which is similar to that in batch under otherwise the same conditions. The slight mass transfer limitation in microreactors was confirmed by performing experiments with microreactors of varying length, and comparing the characteristic mass transfer time and reaction time, indicating further room for improvement. Highlights • The efficient fructose conversion to HMF in deep eutectic solvents was achieved in batch reactors and microreactors. • An HMF yield over 60% could be obtained at a fructose conversion above 90% in both reactors at 80°C within 14 min. • The HMF yield was enhanced from 48% in the monophasic ChCl/EG system to 63% in the DES-MBIK biphasic system in batch. • A slight mass transfer limitation was found in the biphasic slug flow microreactor. Graphical Abstract

Three different types of biomass sourced from forestry waste (eucalyptus residues), agricultural waste (wheat straw), and energy crop (miscanthus) were used as starting materials to produce hemicellulosic sugars, furans (furfural and hydroxymethylfurfural), and oligosaccharides. A two-step hybrid process was implemented; biomass was first autohydrolysed without any additive to extract hemicelluloses and dissolve it in water. Then, the hydrolysate was treated with a solid acid catalyst, TiO2-WOx, in order to achieve hydrolysis and produce monomeric sugars and furans. This article investigates the role of the biomass type, autohydrolysis experimental conditions, polymerisation degree and composition of hemicelluloses on the performance of the process coupling autohydrolysis and catalytic hydrolysis. The highest global yields of both oligosaccharides and monomeric sugars were obtained from Eucalyptus (37% and 18%, respectively).

Seaweed is a sustainable source of marine oligosaccharides that potentially could be used as a prebiotic ingredient for functional food development. The study aims to optimize the oligosaccharide preparation through thermal hydrolysis of an under-utilized red seaweed, Eucheuma denticulatum. Response surface methodology (RSM) applying Box–Behnken design (BBD) was used on three parameters including temperature (105–135 °C), hydrolysis time (15–35 min) and sulfuric acid concentration (0.05–0.2 M). Optimized fractions with good prebiotic activity were characterized using high-performance size-exclusion chromatography (HP-SEC) and Fourier transform infrared spectroscopy (FT-IR). Eucheuma denticulatum oligosaccharides fraction 1 (ED-F1) was shown to promote the growth of beneficial gut microbiota including Lactobacillus plantarum, L. casei, L. acidophilus, Bifidobacterium animalis and B. longum with the highest prebiotic activity score of 1.64 ± 0.17. The optimization studies showed that hydrolysis time was the most significant parameter for the oligosaccharides yield. Optimal hydrolysis conditions for ED-F1 were 120 °C, 21 min, 0.12 M H2SO4 with the highest yield achieved (11.15 g/100 g of dry weight). The molecular weight of ED-F1 was determined at 1025 Da while FT-IR analysis revealed the presence of sulfated oligosaccharides with similar characteristics of i-carrageenan. These findings signify the innovative method for the efficient production of seaweed derived prebiotic oligosaccharides, which could be a promising source of functional food ingredients for the development of health foods and beverages.

Honey is a sweet and natural product of high nutritional value, produced by honey bees (Apis mellifera) composed mainly of water and carbohydrates, nitrogen compounds, enzymes, organic acids, amino acids, phenolic compounds, flavonoids, vitamins, minerals and other phytochemical substances. For cultural reasons, it is widely used for therapeutic purposes for various. However, despite this factor, it is the most fraudulent food in Brazil. On the other hand, it is also marketed in many places without any control, with the appeal of "natural product". Due to its composition can form a compound called 5-hydromethylfurfural or HMF (a furanic ring with functional groups of aldehyde and alcohol), classified as an organic molecule produced from the degradation of sugar after the Maillard reaction that has harmful effects on consumer´s healthy. The main objective of this study was to monitor the quality of honey, a product consumed broadly and increasingly by the population as food and/or medicine. We analyzed 34 honey samples without labeling and/or any type of inspection (US - unregistered samples) obtained in commercial establishments and from unlegalized vendors in the region between the cities of Itatiaia, Resende, Penedo and Visconde de Mauá, all in the Rio de Janeiro State; and 20 samples that had label and identification (RS - registered samples). Aiming to compare the two groups, relevant analyses were performed: pH, Lugol test, Lund test, color and especially 5-HMF. It was concluded that low-cost physicochemical analyses can be used to ensure a fraud-free and quality product that there is no presence of HMF at high concentrations. O mel é um produto doce e natural, de alto valor nutricional, produzido por abelhas melíferas (Apis mellifera) composto principalmente por água e carboidratos, compostos nitrogenados, enzimas, ácidos orgânicos, aminoácidos, compostos fenólicos, flavonoides, vitaminas, minerais e outras substâncias fitoquímicas. Por razões de cunho cultural, é muito utilizado com fins terapêuticos para diversas finalidades. Entretanto, a despeito desse fator, constitui o alimento mais fraudado no Brasil. Por outro lado, também é comercializado em muitos locais sem nenhum controle, com apelo de “produto natural”. Em função de sua composição, pode formar um composto denominado 5-hidroximetilfurfural ou HMF (um anel furânico com grupos funcionais de aldeído e álcool), classificado como uma molécula orgânica produzida a partir da degradação do açúcar após a reação de Maillard que possui efeitos prejudiciais à saúde dos consumidores. O principal objetivo deste estudo foi monitorar a qualidade do mel, um produto consumido de forma ampla e crescente pela população como alimento e/ou medicamento. Foram analisadas 34 amostras de mel sem rotulagem e/ou nenhum tipo de fiscalização (ANR – amostras não registradas) obtidas em estabelecimentos comerciais e de vendedores não legalizados na região entre as cidades de Itatiaia, Resende, Penedo e Visconde de Mauá, todas no Estado do Rio de Janeiro; e 20 amostras que apresentavam rótulo e identificação (AR – amostras registradas), obtidas na cidade de Nova Friburgo, também estado do Rio de Janeiro. Objetivando comparar os dois grupos realizaram-se análises pertinentes como: pH, prova de Lugol, prova de Lund, cor e principalmente o HMF. Concluiu-se que análises físico-químicas de baixo custo podem ser utilizadas para garantir um produto livre de fraude e com qualidade e que não haja presença de HMF em concentrações elevadas.

Most of the foods we eat undergo a cooking process before they are eaten. During such a process, the non-enzymatic browning occurs, which generates compounds such as furosine, 5-hydroxymethylfurfural (HMF) and furfural. These are considered markers of cookedness and can therefore be used as quality indicators. In this work, we study the production of these compounds in different foods (both of plant and animal origin) that are cooked with different techniques. Additionally, we investigate correlations between the production of these markers of cookedness and the antioxidant capacity produced after in vitro digestion and fermentation. We observe that, in general, cereals and vegetables are more thermally damaged. Toasting and frying produce the highest concentrations of Maillard compounds whereas boiling the lowest. Furosine content shows a significant positive correlation with in vitro digestion data in fried foods, and with fermentation in roasted foods. Furfural content shows a significant positive correlation with in vitro digestion results in roasted foods, specifically in the Folin–Ciocalteu method.

The preparation of compounds of interest from biomass-derived 5-hydroxymethylfurfural (HMF) has attracted considerable attention. One such compound is 2,5-diformylfuran (DFF), obtained through oxidation of the hydroxyl group of HMF. Herein, we describe for the first time the whole-cell oxidation of HMF to DFF by Fusarium culmorum EAN 51. Although the chemocatalytic transformation of HMF into DFF has been widely studied, biocatalytic processes have been scarcely reported and are limited to enzymatic synthesis using the combination of several enzymes. The whole-cell transformation of HMF into DFF is preferable thanks to the inherent presence of the different enzymes, significantly reducing the cost of the process. F. culmorum showed a high capability to reduce to 2,5-di(hydroxymethyl)furan (DHMF) and oxidize to DFF the substrate with high yields depending on the nitrogen source and the concentration of peptone and glucose in the media, which highly affected the redox capability of this strain. After careful optimization of the concentration of both nutrients through response surface methodology, 50 mM HMF were transformed into DFF with a high yield (92%) and selectivity (94%). These results open a new line of investigation in the sustainable production of DFF from renewable biobased resources. This work was partially supported by the Spanish Government (PID2019-110735RB-C21, MICIN/FEDER) and the Catalan Government (FI_B1_00135).

Choline chloride (ChCl) / glycolic acid (GA) deep eutectic solvent (DES) media with high water content but without any additional catalyst are introduced in furfural and 5‐hydroxymethylfurfural (HMF) production. The effects of water content, reaction time, and reaction temperature are investigated with two feedstocks: a glucose/xylose mixture and birch sawdust. Based on the results, 10 equivalent quantities of water (32.9 wt.%) were revealed to be beneficial for conversions without rupturing the DES structure. The optimal reaction conditions were 160 °C and 10 minutes for the sugar mixture and 170 °C and 10 minutes for birch sawdust in a microwave reactor. High furfural yields were achieved, namely 62 % from the sugar mixture and 37.5 % from birch sawdust. HMF yields were low, but since the characterization of the solid residue of sawdust, after DES treatment, was revealed to contain only cellulose (49 %) and lignin (52 %), the treatment could be potentially utilized in a biorefinery concept where the main products are obtained from the cellulose fraction. Extraction of products into the organic phase (methyl isobutyl ketone, MIBK) during the reaction enabled the recycling of the DES phase, and yields remained high for three runs of recycling., Acidic choline chloride/glycolic acid/water deep eutectic solvent showed promise in furfural production and sawdust fractionation, without any additional catalyst. The achieved furfural yields were high, 62 % from the sugar mixture and 37.5 % from the sawdust. While 5‐Hydroxyfurfural (HMF) yields were low, this is beneficial in the case of sawdust since the treatments appeared to fractionate the sawdust hemicellulose to furfural while most cellulose and lignin remained solid.

This study examined the effects of different concentrations of high‐fructose corn syrup (HFCS, 28%, 44%, 55%) used in biscuit formulation on the hydroxymethyl furfural (HMF) acrylamide content, and textural properties were investigated and compared with invert sugar and sucrose‐incorporated samples. No significant difference in the chemical composition (moisture, fat, protein, and ash) among different samples was noted based on the results. The highest L* was associated with a control sample containing sugar and invert sugar, although an increase in F55 content decreased the L* value significantly (p, This study examined the effects of different concentrations of high fructose corn syrup (HFCS, 28, 44, 55%) used in biscuit formulation on the Hydroxymethyl furfural (HMF) and acrylamide content and textural properties were investigated and compared with invert sugar and sucrose incorporated samples.

International audience; The Morita-Baylis-Hillman (MBH) reaction of secondary N-alkyl acrylamides, discarded up to now from investigations of the scope of activated alkenes, was studied. Optimization of the reaction conditions reflected that a balance must be found between activation of the MBH coupling reaction and that of the undesired competitive aldehyde Cannizzaro reaction. Using 3-hydroxyquinuclidine (3-HQD) in a 1:1 water-2-MeTHF mixture provides the appropriate conditions were applicable to a wide scope of diversely substituted secondary N-alkyl acrylamides and aromatic aldehydes, giving rise to novel amide-containing MBH adducts under mild and clean conditions.

The ingredients and the preparation methods influence biscuit quality and safety. In Iraq, biscuit imports are increasing every year, but no information is available in the scientific literature on their quality and safety features. This work analyzed three types of biscuits (cookies, crackers, and digestives) sampled in the Basrah markets (Iraq) but produced in Spain, Iran, Turkey, and United Arab Emirates. Nine different brands were considered for each country of origin (n = 36), with three replicates per sample. Moisture, ash, fat, proteins, fiber, water activity, peroxide value, 5-hydroxymethyl-2-furfural (HMF), acrylamide, heavy metals, and microbial load were analyzed. All the nutritional parameters were significantly influenced by the variables “Biscuit type” and “Country”. Cookies showed significantly higher fat content and lower protein content than crackers and digestives, as well as higher peroxide value (which was below the limit set by the FAO/WHO within the World Wood Program). Spanish samples had more fat and fewer proteins than biscuits made in other countries. Very high variability was observed in HMF (from not detected to 62.08 mg/kg) and AA content (reaching 1421.8 μg/kg). Cadmium was always absent, and lead was considerably below the allowed limit. Yeasts and molds were above the limits in five samples.

A novel catalytic strategy involving protective chemistry is presented for the selective production of 5-formylfuran-2-carboxylic acid (FFCA) and furan-2,5-dicarboxylic acid (FDCA) from concentrated 5-hydroxymethylfurfural (HMF) solutions. By protecting the reactive formyl group of HMF by acetalization with 1,3-propanediol (PDO), degradation and premature oxidation of HMF is suppressed. A hydroxyapatite-supported Au catalyst can selectively oxidize HMF-acetal in a 10 wt % solution to FFCA-acetal in 94 % yield in 2 hours at 373 K under 0.5 MPa of O 2. Deprotection of FFCA-acetal by mineral acids affords FFCA in 98 % yield and recovers nearly all PDO. FFCA in a 20 wt % solution can be oxidized to FDCA in 95 % yield under similar reaction conditions. The presented chemistry contributes to the development of novel manufacturing routes of prospective biobased monomer precursors using protecting agents.

The production of polymers from lignocellulosic biomass is currently one of the challenges to minimizing dependence on fossil fuels such as oil. The cellulosic fraction of this feedstock can be transformed into simple sugars such as glucose or fructose. These sugars can be further converted into 2,5-furandicarboxylic acid (FDCA), a precursor of polyethylene furanoate (PEF). The dehydration of sugars to 5-hydroxymethylfurfural (HMF), a platform molecule to obtain products of interest, has been extensively studied. In addition, the oxidation of this platform molecule to FDCA has been widely investigated. However, a study of the direct or one-step production of FDCA from sugars is needed. This review provides a general overview of the recent research on the catalytic systems for the direct production of FDCA from sugars. Ideally, a single-stage system should be employed. The investigations carried out in a one-step process are first detailed. Different strategies have been tested, such as the physical separation of two phases, where dehydration and oxidation took place separately. In this case, an efficient transfer of HMF is needed. To avoid HMF transfer limitations, other authors focused on the investigation of the one-pot transformation of HMF without physical separation. The major requirement of these processes is to achieve catalytic systems functional for both dehydration and oxidation reactions. Therefore, other investigations focused on the study of two-step integrated systems are also analyzed in this review. This research was funded by the University of the Basque Country (UPV/EHU), Basque Government grant number IT1554-22, and the Spanish Ministry of Economy, Industry and Competitiveness grant number MCIN/AEI/PID2021-122736OB-C43.

The aim of this study is to investigate the physicochemical properties, antioxidant activities, and total phenolic contents of the plateau (multifloral), chestnut, rhododendron, and acacia honey collected from Ordu province in Turkey. The rhododendron honey had the highest acidity (p

5-Hydroxy-2-methylfurfural (HMF) has a high derivatization potential and is considered the sleeping giant of biobased platform chemicals. It is accessible by the acid hydrolysis of various carbohydrate-containing feeds, preferably those high in fructose content. We here report a detailed study on the use of thick juice, an intermediate sucrose (SUC)-rich stream in a sugar factory, and pure SUC for the synthesis of HMF in a batch reactor setup [in the presence of water and sulfuric acid (0.01 M) and at 180 °C]. Distinct differences in reactivity were found for both feeds, related to the presence of impurities (i.e., organic acids and salts) in the thick juice. To better understand the effect of the thick juice impurities, detailed model studies were performed involving the use of a model solution of SUC spiked with one of the thick juice impurities (organic acids such as maleic acid and a range of salts with potassium, sodium, calcium, and magnesium as the cations and carbonates, chlorides, and sulfates as the anions). The data were successfully modeled using a kinetic model for the main reactions in the network. The developed model revealed that sulfate anions have a major effect on the HMF yield and the batch time required to reach its optimum and are the likely cause of the differences in reactivity between pure SUC and thick juice.

Furfural (FUR) og 5-hydroksymetylfurfural (HMF) kan dannes ved termokjemisk konvertering av pentose og heksose i fruktrester, samt andre biomasser. Både FUR og HMF anses som høyverdige plattformkjemikalier da de kan brukes videre til å produsere produkter og kjemikalier vi hovedsakelig får fra fossile ressurser, som for eksempel bioplast og biodrivstoff. I dette masterprosjektet har hovedfokuset vært å finne gode metoder for termokjemisk konvertering av fruktrester til HMF, med ubehandlet biomasse fra plommer som råstoff. Med bakgrunn i FNs 17 bærekraftmål (spesielt bærekraftmål 7 og 12) og hvordan den kjemiske industrien kan bidra til å nå disse, har den mer miljøvennlige katalysatoren sulfaminsyre blitt sammenlignet med den industrielt etablerte svovelsyren, med tanke på produktutbytter. Mikrobølgeassistert oppvarming (MWAH) har blitt foreslått som en mer energieffektiv konverteringsmetode og har derfor blitt sammenlignet med konvensjonell oppvarming, også med tanke på produktutbytter. Hvordan temperatur (°C), reaksjonstid (min.), type katalysator og konverteringsmetode påvirker produktutbyttene har blitt undersøkt. Identifisering og kvantifisering av biprodukter har også blitt initiert i dette masterprosjektet. Maksimalt produktutbytte av FUR på 1.3 vekt% ble nådd med sulfaminsyre som katalysator, MWAH, en temperatur på 210 °C og en reaksjonstid på 10 minutter. Maksimalt produktutbytte av HMF på 22 vekt% ble nådd med sulfaminsyre som katalysator, konvensjonell oppvarming, en temperatur på 170 °C og en reaksjonstid på 120 minutter. Generelt viste det seg at sulfaminsyre var positivt for produksjonen av HMF, mens svovelsyre var noe bedre for produksjonen av FUR. Konvensjonell oppvarming ga best utbytte av både FUR og HMF, men MWAH kutter betraktelig ned på reaksjonstider, og en temperatur på 170 °C ga et produktutbytte av HMF på 19 vekt% etter kun 10 minutter reaksjonstid. Den mest signifikante faktoren for produksjonen av FUR og HMF viste seg å være tofaktoren mellom temperatur og reaksjonstid (TempTid), hvor produktutbyttet av både FUR og HMF var antikorrelert til tofaktoren. Reaksjonssystemene har behov for videre optimering, men det ser ut til at en implementering av avfall som råstoff og energieffektive prosesser i den kjemiske industrien, kan bidra til en sirkulær økonomi og bærekraftig utvikling. Furfural (FUR) and 5-hydroxymethylfurfural (HMF) can be formed by thermochemical conversion of pentoses and hexoses in fruit residues, as well as other biomasses. Both FUR and HMF are considered high-value platform chemicals, as they can be further used to produce products and chemicals we mainly get from fossil resources, such as bioplastics and biofuels. In this master's project, the main objective was to find efficient methods for thermochemical conversion of fruit residues to HMF, with untreated biomass from plums as raw material. Given the UN's 17 sustainability goals (especially sustainability goals 7 and 12), and how the chemical industry can contribute to achieving these, the more environmentally friendly catalyst sulfamic acid has been compared to the industrially established sulfuric acid, in terms of product yields. Microwave-assisted heating (MWAH) has been proposed as a more energy-efficient conversion method, and has therefore been compared to conventional heating, also in terms of product yields. How temperature (°C), reaction time (min.), type of catalyst and conversion method affects product yields have been investigated. Identification and quantification of by-products has also been initiated in this master thesis. Maximum FUR yield of 1.3 wt% was reached with sulfamic acid as catalyst, MWAH, a temperature of 210 °C and a reaction time of 10 minutes. Maximum HMF yield of 22 wt% was reached with sulfamic acid as catalyst, conventional heating, a temperature of 170 °C and a reaction time of 120 minutes. In general, it turned out that sulfamic acid was positive for the production of HMF, while sulfuric acid was somewhat better for the production of FUR. Conventional heating gave the best product yields of both FUR and HMF, but MWAH significantly reduces reaction times, and a temperature of 170 °C gave a product yield of HMF of 19 wt% after only 10 minutes reaction time. The most significant factor for the production of FUR and HMF turned out to be the two-factor between temperature and reaction time (TempTid), where the product yield of both FUR and HMF was anticorrelated to the two-factor. The reaction systems need further optimization, but it seems that the implementation of waste as a raw material, and energy-efficient processes in the chemical industry, can contribute to a circular economy and sustainable development. Masteroppgave i kjemi KJEM399K MAMN-KJEM

The aim of the study is to determine the mineral content and some quality parameters of Thrace region floral and honeydew honeys. Quality parameters such as soluble solid, pH, electrical conductivity, free acidity, sugar content and mineral content (Ca, Fe, K, Mg, Na, Zn, P, Se) were determined and evaluated in 25 honey samples including 16 sunflower, 2 gorse, 3 canola, 3 oak and 1 linden honey locally produced in Trace Region, Turkey. Mineral contents of the samples were determined by Inductivelly Coupled Plasma Optical Emission Spectrometer (ICP-OES). The most abundant minerals were potassium, phosphorus and calcium, ranging between 18.91–1018.74, 244.40–429.98 and 8.50–140.82mg/kg, respectively. The mean values were determined as pH 4.42 (3.86-6.54), soluble dry matter 81.4°Bx (79.3-83.0), free acidity 15.66 mEq/kg (9.00-28, 00), HMF 13.00 mg/kg (0.16-33.45), electrical conductivity 595 μS/cm (207-1376), glucose 33.66% (25.51-38.58), fructose 38% .17 (33.32-47.91) and sucrose 0.17% (0.01-0.67)., Çalışmanın amacı, Trakya bölgesi çiçek ve salgı ballarının mineral içeriği ve bazı kalite parametrelerinin belirlenmesidir. Bu amaçla Trakya Bölgesi'nde yerel olarak üretilen 16 adet ayçiçeği, 2 adet karaçalı, 3 adet kanola, 3 adet meşe ve 1 adet ıhlamur balı olmak üzere toplam 25 adet bal örneğinde 8 farklı mineral (Ca, Fe, K, Mg, Na, Zn, P, Se) düzeyi ve bazı tipik kalite parametreleri (çözünür kuru madde, pH, elektriksel iletkenlik, serbest asitlik, HMF ve şeker içeriği) analiz edilmiştir. Bal örneklerinin mineral içerikleri İndüktif Eşleşmiş Plazma Optik Emisyon Spektrometresi (ICP-OES) ile analiz edilmiştir. Ballarda en çok bulunan mineraller sırasıyla potasyum, fosfor ve kalsiyum olup 18.91–1018.74, 244.40–429.98 ve 8.50–140.82 mg/kg arasında belirlenmiştir. Kalite parametreleri ortalama olarak pH 4.42 (3.86-6.54), çözünür kuru madde 81.4°Bx (79.3-83.0), serbest asitlik 15.66 mEq/kg (9.00-28.00), HMF 13.00 mg/kg (0.16-33.45), elektriksel iletkenlik 595 μS/cm (207-1376), glukoz %33.66 (25.51-38.58), fruktoz %38.17 (33.32-47.91), sakkaroz %0.17 (0.01-0.67) olarak tespit edilmiştir.

5-Hydroxymethylfurfural (HMF) is a bio-based platform chemical that can be used as a building block to produce several compounds with diverse applications. Even though HMF synthesis holds promise for a greener future, the current state of technology and the high production cost limit its competitiveness on an industrial scale. In this prospect, we have developed a multigram-scale procedure for HMF by reacting d-fructose with Purolite CT275DR-an acidic resin-in a dimethyl carbonate (DMC)/tetraethyl ammonium bromide (TEAB) biphasic system. Reactions performed in an autoclave for 2 h at 110 °C using up to 40 gram of d-fructose resulted in an overall HMF yield of 70%. HMF was purified by a custom-made procedure leading to ca 50% of the pure crystalline product; meanwhile, the residual HMF-rich oil was directly reduced to bis(hydroxymethyl)furan (BHMF). Green metrics and the Ecoscale algorithm were used to evaluate the sustainability of the herein-proposed procedure in comparison with previously reported works.

The enormous production and consumption of fossil-based plastics has caused severe environmental challenges such as pollution of the ocean, increased CO2-emissions, and various health problems. Many ofthese concerns are intimately connected to the use of fossil fuels in the production of polymers. For this reason, there is a considerable interest to develop bio-based monomers to mitigate some of the issues connected tofossil-based plastics. However, new bio-based monomers are often expensive and need some material advantages to facilitate their market entry. In this context, we have designed several new monomers byconverting bio-based molecules such as 5-chloromethylfurfural (CMF), 5-hydroxymethylfurfural (HMF) and vanillin into rigid diols for polyester and polyurethane synthesis. This thesis has been divided into 5 chaptersdescribing the most important findings from each underlying project.In Chapter 1 and 2, HMF was reacted with pentaerythritol and di(trimethylolpropane) to make two rigid diols with cyclic acetal structures. The monomer made from HMF and pentaerythritol was predicted to have anexceptionally low carbon footprint according to our LCA calculations. These diols were further used to synthesize a series of polyesters and polyurethanes with increased glass transition temperatures. Polyurethanesynthesis was deemed more suitable for this type of monomers, since degradation occurred at the high temperatures required for polyester synthesis. The obtained polyurethanes were used to prepare coatings andtextile fibers. Furthermore, the cyclic acetal structure of the monomers enabled chemical recycling under acidic conditions. In Chapter 3, HMF was produced in a continuous process from fructose, using water anddimethylcarbonate (DMC) in a biphasic system. Both yield and conversion were excellent, demonstrating the utility of DMC for HMF synthesis. The HMF synthesized by this method was sufficiently pure for preparation ofthe monomers in Chapters 1 and 2 in comparable yields to commercial HMF. In Chapter 4, three rigid diols were prepared from CMF and various lignin-based monomeric aldehydes including 4-hydroxybenzaldehyde, vanillin and syringaldehyde. The diol made from vanillin and CMF was used to prepare a series of thermoplastic polyurethanes with increased glass transition temperatures. The polymers were then cross-linked with DielsAlder chemistry, which could be reversed at higher temperature. This may facilitate its reprocessing and recycling. In Chapter 5, two rigid monomers were produced from potentially lignin-derived phenols, and used to prepare a series of polyesters with tunable thermal properties. The polymers could potentially be chemically recycled by acid hydrolysis.

International audience; Oxidative deamination is part of the metabolic pathways of amino acid oxidase and glutamate dehydrogenase enzymes, and enables obtaining α-keto acid from amino compound with ammonia as a by-product. This work presents the utilization of Pt-based catalyst composed of small platinum nanoparticles supported on industrial silica support (Pt/SiO2). This nanozyme was tested in the oxidative deamination reaction of two amino compounds: 5-hydroxymethylfurfurylamine (HMFA) to 5-hydroxymethylfurfural (HMF) and glutamic acid (GA) to α-ketoglutaric acid (KGA). This paper outlines the use of Pt nanozymes with deaminase-like activity. We showed the ability of this nanozymes to be selective and active in liquid phase oxidative deamination of HMFA and glutamic acid in a 6 to 9 pH range at 60°C under atmospheric pressure. Pt/SiO2 nanozyme actually plays as a deaminase mimic with high HMFA conversion (60%) and cumulative yield to the corresponding desaminated keto compounds (67%).

Bu çalışmada; bitki çeşitliliğinin oldukça fazla olduğu Tokat ili ve ilçelerinden temin edilen balların bazı fiziksel ve kimyasal özellikleri belirlenmiştir. 2019 ve 2020 yıllarında 12 ilçeden temin edilen (toplam 24 adet) çiçek balı örneklerinin Türk Standartları (TS) 3036 Bal Standardı ve uluslararası standartlarda kabul görmüş analiz metotları ile yapılan bazı fizikokimyasal, pestisit ve mineral analizleri sonuçlarının Türk Gıda Kodeksi (TGK) Bal Tebliği’ne (2020/7) uygunlukları incelenmiştir. Bal örneklerinde nem miktarı %13,0-20,0; serbest asitlik 26±0,12-48±0,16 meq/kg; elektriksel iletkenlik 0,33-0,86 mS/cm; Hidroksimetilfurfural (HMF) miktarı 0,05-8,69 mg/kg; prolin değeri 422,56-1222,56 mg/kg; diastaz sayısı 0,0-10,9; protein ve ham bal Δ13 C farkı-0.84-1.23; C4 şeker oranı %0,0-5,26; sakkaroz miktarı %0,30- 1,96; früktoz+glikoz miktarı %62,54-76,67; früktoz/glikoz oranı 0,98-2,62 olarak belirlenmiştir. Bal örneklerinde toplam üç numunede pestisit tespit edilmiştir. Bunlar triamenol+triadimefon, metrafenone, cypermethrin, boscalid, deltamethrin, kresoxim methyl olup üç örnekte sınır değerleri aşılmış olup, diğer örneklerde ise limit değerleri aralığındadır. Balların mineral içerikleri (mg/kg); çinko (Zn) 0,0-24,306; nikel (Ni) 0,0-2,906; krom (Cr) 0,0- 3,850; mangan (Mn) 0,0-4,660; bakır (Cu) 0,0-17,099; kurşun (Pb) içeriği 0,314-2,729 aralığında tespit edilmiştir. Örneklerin toplam fenolik madde miktarları 254,14-776,94 μg GAE/g bal; serbest radikali giderme aktivitesi 129,47-587,37 μg TE/g bal; katyon radikali giderme aktivitesi 93,33-1187,78 μg TE/g bal aralıklarındadır. In this study; some physical and chemical properties of honey taken from the districts of Tokat province, where plant diversity is quite high, were determined. Results of some physicochemical, pesticide, and mineral analyses conducted with Turkish Standards (TS) 3036 Honey Standard and internationally accepted analysis methods of flower honey samples (24 in total) obtained from 12 districts in 2019 and 2020 Turkish Food Codex (TGK) Honey Communique (2020/7) has been investigated for compliance. Moisture content in honey samples is 13.0-20%; total acidity 26 }0.12- 48 }0.16 meq/kg; electrical conductivity 0.33-0.86 mS/cm; the amount of hydroxymethylfurfural (HMF) 0.05-8.69 mg/kg; proline value 422.56-1222.56 mg/kg; diastase number 0.0-10.9; protein and raw honey Δ13 C difference -0.84-1.23; C4 sugar content 0.0-5.26%; amount of sucrose 0.30-1.96%; fructose+glucose amount 62.54-76.67%; fructose/glucose ratio was determined as 0.98-2.62. Pesticides were detected in a total of three samples in honey samples. These are triamenol+triadimefon, metrafenone, cypermethrin, boscalid, deltamethrin, and kresoxim methyl. In three samples, the limit values are exceeded, and in the other samples, the limit values are in the range. Mineral content of honey (in mg/kg); zinc (Zn) 0.0-24.306; nickel (Ni) 0.0-2.906; chromium (Cr) 0.0-3.850; manganese (Mn) 0.0-4.660; copper (Cu) 0.0-17.099; lead (Pb) content was determined in the range of 0.314-2.729. The total phenolic content of the samples was 254.14-776.94 μg GAE/g honey; free radical scavenging activity was 129.47-587.37 μg TE/g honey; cation radical scavenging activity was in the range of 93.33-1187.78 μg TE/g honey.

In this study, it was aimed to determine some quality properties of Erzincan mulberry pekmez (molasses) produced with traditional method. For this purpose, various physicochemical properties and antioxidant activity were determined on ten mulberry molasses samples traditionally produced in 2018 and 2019. In the pekmez samples pH 4.86-5.17, titratable acidity 0.53-0.85%, total dry matter 71.91-84.07%, water soluble dry matter 70.60-83.80%, total ash 1.44-3.47%, protein 1.47-3.19%, water activity 0.59-0.75, 5-hydroxymethyl furfural (HMF) 5.70-72.62 mg/kg, total sugar 64.04-71.40%, invert sugar 40.46-56.15%, sucrose 7.76-26.59%, calorie 262.01-294.54 kcal/100 g, viscosity 745-15275 cP, L* value 19.19-32.64, a* value 5.68-17.53, b* value 2.46-9.01, H° value 15.78-52.10 and C* value were detected in the range of 8.74-19.72. Total phenolic content (TFM), 1,1diphenyl-2picyrlhydrazyl (DPPH) antioxidant activity and % inhibition values were found to be in the range of 3.92-10.05 mg GAE/g, 1.31-6.25 mg TE/g and 7.96-30.69%, respectively. According to the results, in general the pekmez samples were found to have quite high nutritional values, to be a good source of antioxidants and TPC, and the amount of HMF remained quite below the limits reported in the TS 12001 Standard (Made From Mulberry). Consequently, it was revealed that molasses which have natural, high nutritional values and health beneficial can be produced with the traditional production technique in Erzincan region. It is thought that these research results will contribute to the importance, promotion, appreciation and protection of Erzincan traditional mulberry pekmez.

Background: Human milk fortifier (HMF) is defined as a supplement added to breastmilk to increase calories, proteins, vitamins, and various nutrition of breastmilk. The purpose of HMF administration is to increase the concentration of breastmilk nutrients to improve the weight of very low birth weight preterm infants. The administration of HMF is insufficient to fulfill protein needs in 20-40% very low birth weight babies, thus the weight gain did not meet the expected target.Objective: To analyze characteristic differences between very low birth weight preterm infants who experienced weight gain according to the target and not according to the target on the administration of HMF.Methods: An analytical study with a case-control approach comparing case and control group, which was observed to determine characteristic differences between both groups. The samples were 52 very low birth weight preterm infants obtained by consecutive sampling. Data analysis includes descriptive analysis and hypothesis testing. Results: Data were obtained from medical records and consisted of 52 participants, including 26 very low birth weight premature infants who experienced weight gain according to the target and 26 who experienced weight gain not according to the target. There was no characteristic difference of cyanosis clinical symptoms (OR 2.3; 95% CI 0.51-10.4), chest retraction (OR 1.0; 95% CI 0.32-3.1), apnea of prematurity comorbid (OR 1.0; 95% CI 0.25-3.9), neonatal infections (OR 0.62; 95% CI 0.21-1.9), starting age of HMF administration (OR 0.62; 95% CI 0.21-1.89), bloating (OR 0.57; 95% CI 0.17-1.9), and vomiting (OR 1.18; 95% CI 0.38-3.7) in both groups.Conclusion: There was no characteristic difference between very low birth weight preterm infants who experienced weight gain according to the target and not according to the target on the administration of HMF.

Akdemir Evrendilek, Gülsün; Ardahan Üniversitesi - Mühendislik Fakültesi - Gıda Mühendisliği Bölümü - Makale, Impacts of pulsed electric fields (PEF) on physicochemical properties, bioactive compounds, and furfural and hydroxymethylfurfural (HMF) formations were quantified for sour cherry juice (SCJ). pH, titratable acidity (TA), total soluble solids (TSS), a*, b*, chroma, and total monomeric anthocyanin content (TMAC) were not significantly affected by 0–0.0341 J/L. The initial total antioxidant capacity (TAC) significantly rose with all the PEF treatments but initial citric, malic, fumaric, oxalic, succinic (−)-epicatechin, ferrulic, gallic, luteolin, p-coumaric, and o-coumaric acids, Cy-3-sop, and Cy-3-glu did not significantly degrade with no formations of furfural and HMF. The best-fit regression models explained 60.1, 39.7, and 36.3% of variation in TAC, TMAC, and TSS, respectively. Frequency exerted a greater impact than did electric field strength (EFS) on TA, pH, TSS, total color difference (TCD), hue, chroma, TMAC, TAC, sinapic, oxalic, quinic and tartaric acids, Cy-3-glu-rut, and furfural formation. 350.9 µs, 6.78 kV/cm, and 98 Hz were pointed as optimal settings.

Honey is a complex foodstuff found in nature which is used without any processing. Honey has been in use in medicine as well as raw food since ancient times. Essentially, it is a blend of sugars especially fructose and glucose. The objectives of the study were to determine major sugar composition as well as pesticides contamination in honey samples. Further, Hydroxy-methyl-furfuraldehyde (HMF) level was also determined to ascertain the freshness of honey samples. A total of 14 samples were collected from local market and tested for fructose, glucose, sucrose, HMF and organochlorine pesticides using HPLC and GC–MS techniques respectively. The total sugars in the 14 honey samples were found ranging between 50.26 and 74.74 g/100 g of honey. The chromatographic results showed the presence of the sugars like fructose and glucose in all honey samples. The honey sample SH–11 was found to contain the highest amount of fructose (40.63%). On the other hand, the lowest amount of fructose with 29.08% was observed in SH–7. The HPLC analysis also revealed the presence of sucrose in two samples but under the permissible limit. The average ratio of fructose to glucose in these honey samples was 1.3. None of the sample has ratio below 1.0 indicating lesser chances for honey to crystallize on storage. Out of 14 honey samples, 13 samples were found negative for the presence of any of the 63 pesticides tested. Only sample No. 13, was found to contain 15.95 ppb hexachlorobenzene per kilogram of honey. The HMF was not detected in four samples but in remaining samples it was well below the maximum permissible limit. No pesticide and sugar adulteration was observed in any of the honey samples. The honeys collected from Saudi Arabian markets were found to confirm the standards set by the regional and international standardization organization, the GSO and Codex Alimentarius Commission respectively.

Cost-effective and environmentally sustainable biorefineries development for simultaneous production of biofuels and value-added chemicals from renewable feedstocks, such as lignocellulosic biomass, constitutes the fundamental foundation for the transition to a circular bioeconomy. The establishment of lignocellulosic biorefineries depends on microorganisms being able to cope with the stressful conditions resulting from the release of inhibitory compounds during pretreatment and hydrolysis steps of biomass processing. In this regard, the yeast Kluyveromyces marxianus emerges as an alternative microbial factory due to its thermotolerance and ability to metabolize several different sugars. Moreover, some studies report K. marxianus ability to cope with lignocellulose-derived inhibitors [1,2]. Despite being generally considered as undesirable inhibitors in lignocellulosic processes, 5-hydroxymethylfurfural (HMF) and furfural are considered promising building-block platforms that can be converted into a wide variety of high-value derivatives with applications in the plastic, pharmaceutical, and textile industries. Up until now, the production of these higher-value derivatives has been mainly based on chemical catalysis, but recently biocatalysis has appeared as a more environmentally friendly alternative. In this work, the potential of K. marxianus strains, isolated from cocoa fermentation, to reduce furfural and HMF at high inhibitory loads was disclosed and characterized. In addition, furans inhibitory effect was higher when combined with xylose consumption. The furan derivatives 2,5-bis(hydroxymethyl)furan (BHMF), 5-hydroxymethyl-2-furan carboxylic acid (HMFCA), furfuryl alcohol and furoic acid produced by K. marxianus in different conditions were identified. Furthermore, one selected isolate was efficiently used as a whole-cell biocatalyst to convert high concentration of furfural and HMF into their derivatives, furfuryl alcohol and BHMF. To the extent of our knowledge, the furfuryl alcohol productivities presented in our work using glucose (5.74 g/L/h) or xylose (6.46 g/L/h), commonly present together with furfural in the hemicellulosic hydrolysates of lignocellulosic biomass, are the highest reported for yeast, and the 99.65% BHMF yield attained is the highest reported in the literature. Our results validate K. marxianus as a promising microbial platform in lignocellulosic biorefineries [3]. References [1] Effect of Binary Combinations of Selected Toxic Compounds on Growth and Fermentation of Kluyveromyces Marxianus. Oliva, J. M.; Ballesteros, I.; Negro, M. J.; Manzanares, P.; Cabañas, A.; Ballesteros, M. Biotechnol. Prog, 20, 3, 715720 (2004). [2] Physiological Response to Furan Derivatives Stress by Kluyveromyces Marxianus SLP1 in Ethanol Production. Flores-Cosio, G.; Arellano-Plaza, M.; Gschaedler, A.; Amaya-Delgado, L. Rev. Mex. Ing. Química, 17, 1, 189202 (2018). [3] Establishment of Kluyveromyces Marxianus as a Microbial Cell Factory for Lignocellulosic Processes : Production of High Value Furan Derivatives. Baptista, M.; Cunha, J. T.; Domingues, L. J. Fungi, 7, 1047 (2021)., This work was funded by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 and of Marlene Baptista PhD scholarship (2020.06888.BD), info:eu-repo/semantics/publishedVersion

In this study; some physical and chemical properties of honey taken from the districts of Tokat province, where plant diversity is quite high, were determined. Results of some physicochemical, pesticide, and mineral analyses conducted with Turkish Standards (TS) 3036 Honey Standard and internationally accepted analysis methods of flower honey samples (24 in total) obtained from 12 districts in 2019 and 2020 Turkish Food Codex (TGK) Honey Communiqué (2020/7) has been investigated for compliance. Moisture content in honey samples is 13.0-20%; total acidity 26±0.12-48±0.16 meq/kg; electrical conductivity 0.33-0.86 mS/cm; the amount of hydroxymethylfurfural (HMF) 0.05-8.69 mg/kg; proline value 422.56-1222.56 mg/kg; diastase number 0.0-10.9; protein and raw honey Δ13 C difference -0.84-1.23; C4 sugar content 0.0-5.26%; amount of sucrose 0.30-1.96%; fructose+glucose amount 62.54-76.67%; fructose/glucose ratio was determined as 0.98-2.62. Pesticides were detected in a total of three samples in honey samples. These are triamenol+triadimefon, metrafenone, cypermethrin, boscalid, deltamethrin, and kresoxim methyl. In three samples, the limit values are exceeded, and in the other samples, the limit values are in the range. Mineral content of honey (in mg/kg); zinc (Zn) 0.0-24.306; nickel (Ni) 0.0-2.906; chromium (Cr) 0.0-3.850; manganese (Mn) 0.0-4.660; copper (Cu) 0.0-17.099; lead (Pb) content was determined in the range of 0.314-2.729. The total phenolic content of the samples was 254.14-776.94 µg GAE/g honey; free radical scavenging activity was 129.47-587.37 µg TE/g honey; cation radical scavenging activity was in the range of 93.33-1187.78 µg TE/g honey., Bu çalışmada; bitki çeşitliliğinin oldukça fazla olduğu Tokat ili ve ilçelerinden temin edilen balların bazı fiziksel ve kimyasal özellikleri belirlenmiştir. 2019 ve 2020 yıllarında 12 ilçeden temin edilen (toplam 24 adet) çiçek balı örneklerinin Türk Standartları (TS) 3036 Bal Standardı ve uluslararası standartlarda kabul görmüş analiz metotları ile yapılan bazı fizikokimyasal, pestisit ve mineral analizleri sonuçlarının Türk Gıda Kodeksi (TGK) Bal Tebliği’ne (2020/7) uygunlukları incelenmiştir. Bal örneklerinde nem miktarı %13,0-20,0; serbest asitlik 26±0,12-48±0,16 meq/kg; elektriksel iletkenlik 0,33-0,86 mS/cm; Hidroksimetilfurfural (HMF) miktarı 0,05-8,69 mg/kg; prolin değeri 422,56-1222,56 mg/kg; diastaz sayısı 0,0-10,9; protein ve ham bal Δ13 C farkı-0.84-1.23; C4 şeker oranı %0,0-5,26; sakkaroz miktarı %0,30-1,96; früktoz+glikoz miktarı %62,54-76,67; früktoz/glikoz oranı 0,98-2,62 olarak belirlenmiştir. Bal örneklerinde toplam üç numunede pestisit tespit edilmiştir. Bunlar triamenol+triadimefon, metrafenone, cypermethrin, boscalid, deltamethrin, kresoxim methyl olup üç örnekte sınır değerleri aşılmış olup, diğer örneklerde ise limit değerleri aralığındadır. Balların mineral içerikleri (mg/kg); çinko (Zn) 0,0-24,306; nikel (Ni) 0,0-2,906; krom (Cr) 0,0- 3,850; mangan (Mn) 0,0-4,660; bakır (Cu) 0,0-17,099; kurşun (Pb) içeriği 0,314-2,729 aralığında tespit edilmiştir. Örneklerin toplam fenolik madde miktarları 254,14-776,94 µg GAE/g bal; serbest radikali giderme aktivitesi 129,47-587,37 µg TE/g bal; katyon radikali giderme aktivitesi 93,33-1187,78 µg TE/g bal aralıklarındadır.

Mirra is a coffee beverage widely consumed in Syria and Turkey, and often produced from roasted and ground coffee beans. Recently, it is prepared from classical instant coffee. In this study, some physicochemical, bioactive and sensory properties of Mirra samples were determined. The average viscosity, degrees Brix, HMF, total phenolic content, DPPH and ABTS values were 1.36 cP, 3.70, 71.60 mg/L, 3431.55 mg GA eq./L, 6.24 mmol Trol. eq./mL and 35.23 mmol Trol. eq./mL for Mirra samples made by traditional process, and 4.85 cP, 16.36, 303.3 mg/L, 11276.47 mg GA eq./L, 23.89 mmol Trol. eq./mL and 89.70 mmol Trol. eq./mL for Mirra samples made with classic instant coffee, respectively. All Mirra samples also contained high levels of caffeine (1416.93 -4347.46 mg/L). Chlorogenic acid, 4-O-caffeoylquinic acid and trans-5-O-caffeoylquinic acid were identified in Mirra samples. Total chlorogenic acid contents of Mirra samples were ranged from 1097.85 to 5283.21 mg/L. In all sensory parameters, Mirras with degrees Brix value over 5.75 had high scores. Results show that Mirra has high antioxidant activity. However, Mirra consumption may have negative health effects for risk groups due to the high caffeine content.

[EN] The direct conversion reaction of glucose to 5-hydroxymethylfurfural (HMF) is studied using metal organic framework (MOF) as Lewis-acid catalysts and a polyoxometalate (POM), silicotungstic acid, as a Brønsted-type acid with a mixture of 1% glucose solution in γ-valerolactone (GVL)-10% HO at 140 °C. The study is carried out with two routes: one using MOF and POM tandem catalysts added independently and the other through the synthesis of a composite material denoted POM@MOF. The activity tests show that the profiles of the conversion and yield of HMF achieved in both routes are similar, with the reactions with MIL-53(Al) and MIL-101(Cr) catalysts producing the highest yield of HMF (40% after 8 h of reaction). Stability tests are performed on the POM@MOF catalysts based on MIL-53(Al) and MIL-101(Cr). MIL-53(Al) and HSiW@MIL-101(Cr) can be reused, showing a progressive loss in HMF yield due to the leaching of POM., https://digital.csic.es/dc/listadoMetadatos.jsp?ID=dc_contributor_funder&vocabulary=funder&plataforma=pasarela

HMF_raw_occurrence_zenodo.CSV contains the raw occurrence dataset on hydroxymethylfurfural (HMF) contaminant as extracted from EFSA DWH in August 2021 on 219 samples of bee feed presented in the opinion as described in its section 3.2.1. Occurrence data submitted to EFSA. The data is provided in .csv format. This dataset is compliant with EFSA SSD model and contains two additional columns documenting issues identified in the cleaning process (column: issue) and the action taken (column: outcome) to address the issue (e.g. delete record or update values in specific fields).

WOS:000762352400001 Hydroxymethylfurfural (HMF) is a chemical contaminant that is not naturally present in carbohydrate-containing food samples. The HMF amounts were changed between 4.8 and 214.1 mg/kg in honey; between 7.8 and 204.0 mg/kg in pekmez (grape molasses); between 5.9 and 22.4 mg/kg in strawberry jam; between 6.0 and 65.4 mg/kg in apricot jam; and between 9.2 and 55.9 mg/kg in cherry found by HPLC. The linear calibration plot of HMF was ranged from 0.05 to 10.0 mu g/ml. The correlation coefficient was found to be 0.99997. LOD and LOQ values were found to be 12.0 and 40.0 ng/ml, respectively. According to the experimental results, HMF amounts of four honey samples, three pekmez (grape molasses) samples, one apricot jam, and one cherry jam for investigated samples were found to be higher than the permission amount of Turkish Food Codex. Novelty impact statement Based on experimental results in this study, if the honey is in a transparent package such as a glass, it should be stored in a dark environment. It would be healthier to prefer molasses produced by reliable brands at low temperatures under vacuum instead of molasses made with traditional methods in open boilers. Generally, since jams with high HMF amount have an overcooked or even burnt flavor, this is an extremely negative situation for consumers.

Honey is a natural product which has high nutritional value. Also, it has health benefits, which is the reason for its been used for the prevention of diseases caused by oxidative stress for centuries in many countries. Honey has antibacterial and antioxidant properties, which are the result of the presence of enzymes and chemical and phytochemical components, where phenolic acids and flavonoids play a significant role. The aim of this study was to examine the physico-chemical parameters, antioxidant properties and antimicrobial activity of forest-meadow, acacia and sunflower honey from the Gruža and Požega areas (Republic of Serbia). The tested physico-chemical parameters were found to be within the values prescribed by the Legislation and the Codex Alimentarius Standard. The presence of HMF was not detected in the sample of forest-meadow honey, while the content in other samples (1.09 and 1.79 mg HMF kg-1) was significantly below the value laid down by regulations (40 mg HMF kg-1). Forest-meadow honey had the highest antioxidant activity (35.2%, 26.32%-ABTS and DPPH method, respectively) and the highest content of total phenolics (90.96±5.18 g GAE 100 g-1), while acacia honey exhibited the lowest values for antioxidant activity (11.76%-ABTS; 7.28%-DPPH) and total phenolics (15.75±0,66 g GAE 100 g-1). Forest-meadow honey showed the best antibacterial activity, followed by sunflower and acacia honey.

International audience; Noble metal-free catalysts based on earth-abundant and inexpensive mixed oxides are active catalysts of all steps of the reaction cascade leading from 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) using tert-butyl hydroperoxide (TBHP) as oxidation agent. Catalysts covering the whole range of composition in the Cu-Mn and Co-Fe series have been prepared and characterised. The nature and composition of the catalyst strongly affect conversion and selectivity. The distribution of products indicates that radical-type oxygen species, deriving from the activation of TBHP, play a determining role in the reaction. The early steps of reaction mainly follow the pattern expected for heterogeneous Fenton catalysts. Mixed oxide catalysts are the most effective in further oxidation steps, leading to the formation of FDCA, both in the Cu-Mn and Co-Fe systems. This behaviour can be related to the distribution of charge in the mixed oxides, suggesting a possible implication of the lattice oxygen in the last reaction steps. The results provide indications on how to optimize the reaction and minimize the formation of byproducts (humins and oligomers).

The most widely used whey protein ingredient in an infant formula (IF) is the whey protein concentrate (WPC). The processing steps used in the manufacturing of both a powdered IF and a WPC introduce protein modifications that may decrease the nutritional quality. A gently processed whey protein ingredient (serum protein concentrate; SPC) was manufactured and used for the production of a powdered IF. The SPC and the SPC-based IF were compared to the WPC and the powdered WPC-based IF. Structural protein modifications were evaluated, and Maillard reaction products, covering furosine, alpha-dicarbonyls, furans, and advanced glycation end products, were quantified in the IFs and their protein ingredients. IF processing was responsible for higher levels of protein modifications compared to the levels observed in the SPC and WPC. Furosine levels and aggregation were most pronounced in the WPC, but the SPC contained a high level of methylglyoxal, revealing that other processing factors should be considered in addition to thermal processing.

In this study we aimed to investigate the effect of heat treatment on the spectral pattern of honey using near infrared spectroscopy (NIRS). For the research, sunflower, bastard indigo, and acacia honeys were collected from entrusted beekeepers. The honeys were not subject to any treatment before. Samples were treated at 40 °C, 60 °C, 80 °C, and 100 °C for 60, 120, 180, and 240 min. This resulted in 17 levels, including the untreated control samples. The 5-hydroxymethylfurfural (HMF) content of the honeys was determined using the Winkler method. NIRS spectra were recorded using a handheld instrument. Data analysis was performed using ANOVA for the HMF content and multivariate analysis for the NIRS data. For the latter, PCA, PCA-LDA, and PLSR models were built (using the 1300–1600 nm spectral range) and the wavelengths presenting the greatest change induced by the perturbations of temperature and time intervals were collected systematically, based on the difference spectra and the weights of the models. The most contributing wavelengths were used to visualize the spectral pattern changes on the aquagrams in the specific water matrix coordinates. Our results showed that the heat treatment highly contributed to the formation of free or less bonded water, however, the changes in the spectral pattern highly depended on the crystallization phase and the honey type.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Dependence on oil as a source of fuel and raw material to produce chemical products opens space for the development of catalytic systems aimed at the use of biomass. In this sense, this work aims to develop a new route to produce FDCM, a monomer used in the production of PEF bioplastic, a substitute for PET. The new reaction route is the dehydrogenation of HMF in an inert atmosphere, using catalysts of Au and Cu supported on different oxides (ZrO2, SiO2 and MgO). The advantage of producing FDCM directly from HMF is the production of H2 as a co-product. There are no reports in the literature on the use of this reaction system, but the rich literature on the dehydrogenation reaction of ethanol in an inert atmosphere serves as a basis. In the ethanol reaction, the importance of having a good knowledge of the catalyst surface is known, as the electronic density of the metallic species, the chosen support, as well as the metal-support interface control the selectivity for acetaldehyde or ethyl acetate. Thus, the following catalysts were synthesized and characterized: Au/m-ZrO2, Au/SiO2, Au/Mg(OH)2, Cu/m-ZrO2, Cu/SiO2 and Cu/MgO with different metal contents. The characterizations revealed that the support used has a major influence on the structural and surface properties of metallic nanoparticles. For gold catalysts, the largest nanoparticles were obtained in materials supported on silica, while in the other two supports, the nanoparticles are smaller. Furthermore, the surface of Au/SiO2 has fewer defects than that of Au/m-ZrO2. Finally, the TPR results of the Au/Mg(OH)2 samples revealed that above 400 °C, the formation of a metallic alloy between Mg-Au may be occurring. For copper catalysts, it was observed that Cu/SiO2 and Cu/MgO have small nanoparticles well dispersed on the support, with the largest dispersion being attributed to the copper species present in the magnesium oxide, while the Cu/ m-ZrO2 materials have larger and more agglomerated metallic nanoparticles than in the other two supports. The electronic density of copper species present on the surface of these catalysts was illustrated by the FTIR-CO technique and the calculation of the Cu0/Cu+ ratio revealed the following order: Cu/MgO > Cu/m-ZrO2 > Cu/SiO2. When applied in the reaction, using the flow and batch system, the catalyst that showed the best result, for both systems, was Au/SiO2, which had the highest selectivity for FDCM. Furthermore, the Cu/m-ZrO2 catalyst was selective only for the reaction of the aldehyde group of HMF. The results obtained in this work will serve as a basis for the improvement of the proposed system, since the selectivity to FDCM was not remarkably high, in addition to the high degradability of HMF under the conditions evaluated in this work. A dependência do petróleo como fonte de combustíveis e matéria prima para produção de produtos químicos, abre espaço para o desenvolvimento de sistemas catalíticos que visam a utilização da biomassa. Nesse sentido, esse trabalho visa o desenvolvimento de uma nova rota para a produção do FDCM, um monômero utilizado na produção do bioplástico PEF, substituto do PET. A nova rota de reação é a de desidrogenação do HMF em atmosfera inerte, utilizando catalizadores de Au e Cu suportados em diferentes óxidos (ZrO2, SiO2 e MgO). A vantagem da produção de FDCM diretamente do HMF, é a produção de H2 gasoso como coproduto. Não existem relatos na literatura da utilização desse sistema de reação, porém a rica literatura na reação de desidrogenação do etanol em atmosfera inerte, serve como base. Na reação do etanol, sabe-se da importância de se ter um bom conhecimento da superfície do catalisador, pois a densidade eletrônica das espécies metálicas, o suporte escolhido, bem como a interface metal-suporte controlam a seletividade para acetaldeído ou para acetato de etila. Dessa forma, foram sintetizados e caracterizados os catalisadores: Au/m-ZrO2, Au/SiO2, Au/Mg(OH)2, Cu/m-ZrO2, Cu/SiO2 e Cu/MgO com diferentes teores de metal. As caracterizações revelaram que o suporte utilizado tem grande influência nas propriedades estruturais e de superfície das nanopartículas metálicas. Para os catalisadores de ouro, as maiores nanopartículas foram obtidas nos materiais suportados em sílica, enquanto nos outros dois suportes, provavelmente, as nanopartículas são menores. Além disso, a superfície do Au/SiO2 possui menos defeitos que a do Au/m-ZrO2. Por fim, os resultados de TPR das amostras de Au/Mg(OH)2, revelaram que acima de 400 °C, pode estar ocorrendo a formação de uma liga metálica entre Mg-Au. Para os catalisadores de cobre, foi possível observar que os Cu/SiO2 e Cu/MgO são constituídos de nanopartículas pequenas e bem dispersas sobre o suporte, sendo a maior dispersão atribuída as espécies de cobre presentes no óxido de magnésio, enquanto os materiais Cu/m-ZrO2 possuem nanopartículas metálicas maiores e mais aglomeradas que nos outros dois suportes. Já a densidade eletrônica das espécies de cobre presente na superfície desses catalisadores, foi ilustrada pela técnica de FTIR-CO e o cálculo da razão Cu0/Cu+ revelou a seguinte ordem: Cu/MgO > Cu/m-ZrO2 > Cu/SiO2. Quando aplicados na reação, utilizando o sistema em fluxo e em batelada, o catalisador que apresentou melhor resultado, para ambos os sistemas, foi o Au/SiO2, que teve a maior seletividade para o FDCM. Além disso, o catalisador Cu/m-ZrO2 foi seletivo apenas para a reação do grupo aldeído do HMF. Os resultados obtidos nesse trabalho, servirão de base para o aprimoramento do sistema proposto, uma vez que a seletividade a FDCM não foi muito alta, além da alta degradabilidade do HMF nas condições testadas nesse trabalho. CAPES: Código de Financiamento 001

The establishment of lignocellulosic biorefineries is dependent on microorganisms being able to cope with the stressful conditions resulting from the release of inhibitory compounds during biomass processing. The yeast Kluyveromyces marxianus has been explored as an alternative microbial factory due to its thermotolerance and ability to natively metabolize xylose. The lignocellulose-derived inhibitors furfural and 5-hydroxymethylfurfural (HMF) are considered promising building-block platforms that can be converted into a wide variety of high-value derivatives. Here, several K. marxianus strains, isolated from cocoa fermentation, were evaluated for xylose consumption and tolerance towards acetic acid, furfural, and HMF. The potential of this yeast to reduce furfural and HMF at high inhibitory loads was disclosed and characterized. Our results associated HMF reduction with NADPH while furfural-reducing activity was higher with NADH. In addition, furans’ inhibitory effect was higher when combined with xylose consumption. The furan derivatives produced by K. marxianus in different conditions were identified. Furthermore, one selected isolate was efficiently used as a whole-cell biocatalyst to convert furfural and HMF into their derivatives, furfuryl alcohol and 2,5-bis(hydroxymethyl)furan (BHMF), with high yields and productivities. These results validate K. marxianus as a promising microbial platform in lignocellulosic biorefineries.

The table olive industry is producing a huge amount of wastewater, which is a post-processing cost and an environmental concern. The present study aims to valorize this processing by-product to obtain a value-added product, thereby enhancing resource efficiency and contributing to achieving sustainable development goals (SDGs). In this sense, a chemical reaction-based platform was developed to obtain valuable components, such as levulinic acid (LA) and 5-hydromethylfurfural (HMF). The products were then analyzed using NMR identification of the antioxidant phenolic fraction and microwave single-phase reaction of the sugary fraction. According to the results, the highest concentration of phenolic compounds does not correspond to the sample directly obtained from NaOH treatment (S1), indicating that water washing steps (S2–S5) are fundamental to recover phenolic substances. Moreover, glucose was presented in the sugary fraction that can be transformed into levulinic acid by a single-phase reaction under microwave irradiation. The information provided in this manuscript suggests that the wastewater from the olive processing industry can be valorized to obtain valuable products.

This work aims to systematically investigate the influence of process temperature, biomass-to-water ratio, and production scales (laboratory and pilot) on the chemical composition of aqueous and gaseous phases and mass production of chemicals by hydrothermal processing of Açaí (Euterpe oleraceae, Mart.) seeds. The hydrothermal carbonization was carried out at 175, 200, 225, and 250 °C at 2 °C/min and a biomass-to-water ratio of 1:10; at 250 °C at 2 °C/min and biomass-to-water ratios of 1:10, 1:15, and 1:20 in technical scale; and at 200, 225, and 250 °C at 2 °C/min and a biomass-to-water ratio of 1:10 in laboratory scale. The elemental composition (C, H, N, S) in the solid phase was determined to compute the HHV. The chemical composition of the aqueous phase was determined by GC and HPLC and the volumetric composition of the gaseous phase using an infrared gas analyzer. For the experiments in the pilot test scale with a constant biomass-to-water ratio of 1:10, the yields of solid, liquid, and gaseous phases varied between 53.39 and 37.01% (wt.), 46.61 and 59.19% (wt.), and 0.00 and 3.80% (wt.), respectively. The yield of solids shows a smooth exponential decay with temperature, while that of liquid and gaseous phases showed a smooth growth. By varying the biomass-to-water ratios, the yields of solid, liquid, and gaseous reaction products varied between 53.39 and 32.09% (wt.), 46.61 and 67.28% (wt.), and 0.00 and 0.634% (wt.), respectively. The yield of solids decreased exponentially with increasing water-to-biomass ratio, and that of the liquid phase increased in a sigmoid fashion. For a constant biomass-to-water ratio, the concentrations of furfural and HMF decreased drastically with increasing temperature, reaching a minimum at 250 °C, while that of phenols increased. In addition, the concentrations of CH3COOH and total carboxylic acids increased, reaching a maximum concentration at 250 °C. For constant process temperature, the concentrations of aromatics varied smoothly with temperature. The concentrations of furfural, HMF, and catechol decreased with temperature, while that of phenols increased. The concentrations of CH3COOH and total carboxylic acids decreased exponentially with temperature. Finally, for the experiments with varying water-to-biomass ratios, the productions of chemicals (furfural, HMF, phenols, cathecol, and acetic acid) in the aqueous phase is highly dependent on the biomass-to-water ratio. For the experiments at the laboratory scale with a constant biomass-to-water ratio of 1:10, the yields of solids ranged between 55.9 and 51.1% (wt.), showing not only a linear decay with temperature but also a lower degradation grade. The chemical composition of main organic compounds (furfural, HMF, phenols, catechol, and acetic acid) dissolved in the aqueous phase in laboratory-scale study showed the same behavior as those obtained in the pilot-scale study.

The production of 2,5-furandicarboxylic acid (FDCA) from the selective oxidation of 5-hydroxymethylfurfural (HMF) is a critical step in the production of biopolymers from biomass-derived materials. In this study, we report the catalytic performance of monometallic Au and Pd, and bimetallic AuPd nanoparticles with different Au : Pd molar ratios synthesised under continuous flow conditions using a millifluidic set-up and subsequently deposited onto titanium dioxide as the chosen support. This synthetic technique provided a better control over mean particle size and metal alloy composition, that resulted in higher FDCA yield when the catalysts were compared to similar batch-synthesised materials. A 99% FDCA yield was obtained with the millifluidic-prepared AuPd/TiO2 catalyst (Au : Pd molar composition of 75 : 25) after being calcined and reduced at 200 °C. The heat treatment caused a partial removal of the protective ligand (polyvinyl alcohol) encapsulating the nanoparticles and so induced stronger metal-support interactions. The catalyst reusability was also tested, and showed limited particle sintering after five reaction cycles.

The major drawback of chemical transformations for the production of 2, 5-furan dicarboxylic acid (FDCA) implies the usage of hazardous chemicals, high temperature and high pressure from nonrenewable resources. Alternate to chemical methods, biological methods are promising. Microbial FDCA production is improved through engineering approaches of media conditions, homologous and heterologous expression of genes, genetic and metabolic engineering, etc. The highest FDCA production of 41.29 g/L is observed by an engineered Raultella ornitholytica BF 60 from 35 g/L HMF in sodium phosphate buffer with a 95.14% yield in 72 h. Also, an enzyme cascade system of recombinant and wild enzymes like periplasmic aldehyde oxidase ABC, galactose oxidase M3-5, HRP and catalase have transformed 6.3 g/L HMF to 7.81 g/L FDCA in phosphate buffer with 100% yield in 6 h. Still, these processes are emerging for fulfilling the industrial needs due to the challenges in ‘green FDCA production’., Graphical Abstract

International audience; New highly functionalized scaffolds, namely 2-(2-furyl)hydroxymethyl-2-cycloalkenones, are reported. The access to these systems is one step using an aqueous Morita–Baylis–Hillman reaction combining hydroxymethylfurfural and glucosyloxymethylfurfural and cycloalkenones for which the reaction conditions (promoter, solvent, concentration, and stoichiometry) have been optimized.; De nouvelles architectures fonctionnalisées de type 2-(2-furyl)hydroxyméthyl-2-cycloalcénone sont décrites. L'accès à ces systèmes se fait en une seule étape par réaction de MoritaeBayliseHillman (MBH) dans l'eau associant le HMF ou le GMF avec des cycloalcénones, pour laquelle les conditions (promoteur, concentration, stoechiométrie) ont été optimisées.