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Amongst the many forms of food waste, bread is a major contributor to the problem. Two aims of this research investigate waste breads potential of being a bioresource for the production of fermentable sugars which are precursor of valuable bioproducts by fermentation process: finding optimum substrate, water and enzyme ratio to produce the highest amount of fermentable sugars and investigating the rheological behavior of the system during hydrolysis. Two stage waste bread hydrolysis was performed with enzymes α-amylase and amyloglucosiades and response surface methodology was used to optimize substrate, water and enzyme ratio. Discovery Hybrid Rheometer-2 (TA Instruments) fitted with a parallel-plate geometry was used to investigate steady flow viscosity of the slurry during hydrolysis. 99 % of theoretical maximum glucose yield, a main fermentable sugar, is achieved by optimizing enzymatic hydrolysis conditions of waste bread at liquefaction and saccharification stages. Just after the addition of α-amylase enzyme, substantial decrease is observed in viscosity and Casson apparent yield stress of the slurry. During saccharification stage, glucose yield increases dramatically while viscosity of the slurries is very low and does not change considerably. The results imply that utilizing high concentrations of waste bread as a feedstock to produce fermentation products offers economic benefits without causing high power consumption, excessive wear on equipment, and reduced conversion which are generally expected consequences for high-solid processing. [ABSTRACT FROM AUTHOR]

Development of bioprocess routes for production of value-added materials from food waste is very attractive in terms of bioprocess economics and environmental protection. In this study, production of 2-keto-d-gluconic acid, a significant platform chemical, from food waste was performed by Pseudomonas reptilivora NRRL B-6 for the first time. The nitrogen source preference of the strain for 2-keto-d-gluconic acid production under different glucose concentrations in synthetic medium has been elucidated. At higher glucose concentrations, utilization of organic nitrogen source (yeast extract) led to higher product formation while at lower glucose concentration, utilization of inorganic nitrogen source (ammonium chloride) was also very feasible. The results indicated that favorable nitrogen source for 2-keto-d-gluconic acid production can change depending on the glucose concentration. The waste bread hydrolysate (glucose 181.43 g/L, protein 1.21% (w/v)) prepared by sequential application of α-amylase, amyloglucosidase, and protease was utilized in medium formulation at different glucose concentrations. Bread hydrolysate without additional supplements provided higher product formation than the optimum medium prepared with the hydrolysate. Utilization of 50 g/L CaCO3 led the maximum product formation. The maximum 2-keto-d-gluconic acid production from waste bread was 142.81 g/L with the productivity of 3.02 g/L/h and molar yield of 0.95. The proposed approach in this study confirms that waste bread as a sole source of nutrients can be valorized for microbial production of various industrially relevant platform chemicals. [ABSTRACT FROM AUTHOR]

Activated carbon foam was prepared via direct pyrolysis of waste bread (WB) under CO2 atmosphere. The product was characterized by N2 adsorption/desorption and Fourier transform infrared spectroscopy (FTIR). The preparation process was investigated online by a thermogravimetric analyzer coupled with FTIR (TG-FTIR). The adsorption isotherms of methylene blue (MB) by the product were investigated. The experimental data demonstrated that the product had a high surface area of 1575 m2 g−1 and a total pore volume of 0.883 cm3 g−1. Thermal decomposition of polymers in WB mainly occurred between 200 and 500 °C, leading to the release of carbonyl compounds, aliphatic hydrocarbons, alcohols, and furans. The dominant CO2 activation process started at above 800 °C. The MB adsorption equilibrium data followed Langmuir model with a monolayer adsorption capacity of 403 mg g−1. This study provides a reference for the utilization of WB as a promising precursor of activated carbon foam adsorbent, which has highly porous structure and excellent floatability in water. [ABSTRACT FROM AUTHOR]

Bioethanol production from agro-food industry waste is one of the suitable alternatives to fossil fuels. In this study, six agro-food wastes were evaluated to select those with a high concentration of starch or fermentable sugars for bioethanol processing. Yeast's ability to produce biofuels by fermentation is affected by temperature. In this study, thermotolerant yeasts, obtained from natural sources in Algeria (soil and agro-food waste), were selected for their capacity to produce and tolerate bioethanol. Three wastes were selected, two of which had significant starch content. In order to get fermentable sugars, these wastes underwent chemical and enzymatic hydrolysis. The selected yeasts were identified by morphological, physiological, biochemical, and molecular characterization. Enzymatic and acid hydrolysis of whole potato and durum wheat bran released (190 g/L and 130 g/L) and (138.40 g/L and 90.03 g/L) reducing sugars, respectively. Among the isolated strains, three were found to be able to produce bioethanol, namely Candida tropicalis, Candida glabrata, and Saccharomyces cerevisiae. These strains were identical to those stored in the data bank with 99%, 100%, and 100%, respectively. In addition, C. glabrata and C. tropicalis exhibited an ethanol tolerance of up to 14%, while S. cerevisiae tolerates up to 15%. Interestingly, enzymatic hydrolysis–treated potatoes produced a considerable amount of bioethanol after 48 h of fermentation by S. cerevisiae (7.525% (v/v)), C. glabrata (6.80% (v/v)), and C. tropicalis (4.50% (v/v)). Taken together, our findings suggest that S. cerevisiae and whole potato waste could be considered good candidates for industrial bioethanol production at high temperatures. [ABSTRACT FROM AUTHOR]

In this study, we performed co-digestion of industrial food wastewater in a hybrid upflow anaerobic sludge blanket (HUASB) reactor by dark fermentation (DF). Hydraulic retention times (HRT) of 3, 8, and 12 h at a minimum of 30 cycles were tested to determine their effects on hydrogen production and microbial population diversity. The results indicated that HRTs of 3, 8, and 12 h produced hydrogen concentrations of 45 ± 10%, 50 ± 10%, and 36 ± 14%, respectively, and the rest was mostly CO2. The microbial community structure indicated that Lactobacillus plantarum, L. fermentum, L. casei, and L. delbrueckii proliferated mainly at HRT ≤ 8 h. The 50-cycle HUASB operating conditions at an HRT of 8 h yielded 3.68 ± 2.83 mL H2 gCODremoved−1 and a volumetric hydrogen production rate of 0.1 L H2 L−1 day−1. [ABSTRACT FROM AUTHOR]

Waste wheat bread was hydrolyzed using amylolytic enzymes and dilute hydrochloric acid, and the effects of process variables on glucose yield, aflatoxin fate, and ethanol production were studied. Dilute acid hydrolysis was performed with a full factorial experimental design with three levels for acid concentration, i.e., 0.32%, 1%, and 2% (v/v), and three levels for hydrolysis time, i.e., 0, 10, and 20 min at 121 °C. For enzymatic hydrolysis, the samples were first liquefied, and the saccharification of liquefied samples was performed via a rotatable central composite design with two levels of 10 and 48 h for time and two levels of 100 and 150 g/L for substrate loading. The highest glucose yield of 69.8% was obtained from the experiment with acid concentration of 1% and hydrolysis time of 20 min. The maximum glucose yield of 93% was obtained in enzymatic hydrolysis at 55 h and 125 g/L substrate loading. The general linear model was used to model the glucose yields obtained in dilute acid hydrolysis, while the results of enzymatic hydrolysis were best fit to the quadratic model. In the optimized condition for dilute acid and enzymatic hydrolysis, aflatoxin B1 was completely removed by dilute acid hydrolysis, and amylolytic enzymes enabled to remove up to 75% aflatoxin B1. The highest glucose obtained during dilute acid and enzymatic hydrolysis yielded a maximum of 86.9% and 83.0% of theoretical ethanol, respectively, corresponding to 248 and 313 g ethanol per kilogram dry bread residues. [ABSTRACT FROM AUTHOR]

The development of hydrogen energy is in progress as one of the key paths for achieving net-zero and carbon–neutral society. Significant attention is currently being paid to pathways for biomass-based hydrogen production, as the utilization of biomass energy is more sustainable than that of fossil fuels. In this study, the production of hydrogen from biomass gasification and reforming is modeled with Aspen Plus®. This process model is built to simulate thermo-physical properties and operating characteristics of syngas production through the gasification of woodchip and tar reforming, and the conversion of syngas to hydrogen, based on steam reforming and water gas shifting reaction. The hydrogen production rate and production costs are evaluated considering biomass feedstock's with different moisture content, ash content, and particle sizes. [ABSTRACT FROM AUTHOR]

Β-glucans are polysaccharide macromolecules that can be found in the cell walls of molds, such as Rhizopus oryzae. They provide functional properties in food systems and have immunomodulatory activity, anticancer, and prebiotic effects; reduce triglycerides and cholesterol; and prevent obesity, among others benefits. Furthermore, potato starch production requires a large amount of water, which is usually discharged into the environment, creating problems in soils and bodies of water. The physical parameters to produce β-glucans were determined, liquid waste from potato starch processing was used and native Rhizopus oryzae was isolated and identified from cereal grains. The isolates grew quickly on the three types of agars used at 25 °C and 37 °C, and they did not grow at 45 °C. Rhizopus oryzae M10A1 produced the greatest amount of β-glucans after six days of culture at 30 °C, pH 6, a stirring rate of 150 rpm and a fermentation volume of 250 mL. By establishing the physical fermentation parameters and utilizing the liquid waste from potato starch, Rhizopus oryzae M10A1 yielded 397.50 mg/100 g of β-glucan was obtained. [ABSTRACT FROM AUTHOR]

Recently, hydrogen gas is becoming the most prominent alternative fuel due to its clean and environment-friendly nature. It only delivers water as a waste product during the operation instead of emitting harmful greenhouse gases. It has a high heating value (142 MJ/kg), over 2.75 times that of other hydrocarbon-based petroleum fuels. Presently, the primary method of producing hydrogen is the steam reforming of fossil fuels, which is not economical and environmentally harmful, and fossil fuels are on the deadline to finish. Hence, alternative methods of hydrogen production are the topic of current research. Biological methods of hydrogen production were found the best for producing green hydrogen because they utilize plentiful available renewable sources as feedstock. The dark fermentation technique is becoming more famous among all biological hydrogen generation methods because of its light autonomous nature and functional ability. It has the facility to convert any type of carbohydrate-rich organic substrates into bio-hydrogen, but pure carbohydrate substances are not economical on a commercial scale. Hence, carbohydrate-rich organic waste can be easily harnessed for bio-hydrogen generation. This method yields hydrogen gas and different high-volatility fatty acids, which could be used for industrial purposes after separation or as a precursor for the bio-methanation process for biogas production. This paper defines mechanism, microbiology, affecting factors, various integration methodologies, and potential and limitations related to the dark fermentation method. [ABSTRACT FROM AUTHOR]

Background, aim, and scope: The aim of this study has been to estimate the carbon footprint of bread produced and consumed in the UK. Sliced white and wholemeal bread has been considered for these purposes and the functional unit is defined as 'one loaf of sliced bread (800 g) consumed at home'. The influence on the carbon footprint of several parameters has been analysed, including country of origin of wheat (UK, Canada, France, Germany, Spain and USA), type of flour (white, brown and wholemeal) and type of packaging (plastic and paper bags). The effect on the results of the type of data (primary and secondary) has also been considered. Materials and methods: The carbon footprint has been estimated in accordance with the PAS 2050 methodology. The results have also been calculated following the ISO 14044 methodology to identify any differences in the two approaches and the results. Primary data for the PAS 2050-compliant study have been collected from a UK bread supply chain. Secondary data have been sourced from the UK statistics, life cycle inventory databases and other published sources. Results and discussion: The carbon footprint results range from 977 to 1,244 g CO eq. per loaf of bread. Wholemeal thick-sliced bread packaged in plastic bags has the lowest carbon footprint and white medium-sliced bread in paper bag the highest. The main hot spots are wheat cultivation and consumption of bread (refrigerated storage and toasting), contributing 35% and 25% to the total, respectively. Conclusions: The carbon footprint could be reduced on average by 25% by avoiding toasting and refrigerated storage of bread. Further reductions (5-10%) could be achieved by reducing the amount of waste bread discarded by consumers. The contribution of transport and packaging to the overall results is small. Similar trends in the results are also found in the study based on the secondary data and following the ISO 14044 methodology. [ABSTRACT FROM AUTHOR]

An endophytic bacterium Paenibacillus polymyxa DS-R5 which can effectively inhibit the growth of pathogenic fungi was isolated from Salvia miltiorrhiza in our previous study. By using hydrochloric acid precipitation, methanol extraction, silica gel column isolation, dextran gel chromatography column, and HPLC, 3 compounds with antifungal activity were isolated. To further improve the production of antifungal compounds produced by this strain, fermentation medium was optimized using one-factor-at-a-time, Plackett–Burman design, and Box–Behnken design experiments. Through statistical optimization, the optimal medium composition was determined to be as follows: 14.7 g/l sucrose, 20.0 g/l soluble starch, 7.0 g/l corn steep liquor, 10.0 g/l (NH4)2SO4, and 0.7 g/l KH2PO4. In this optimized medium, the highest titer of antifungal compounds reached 3452 U/ml, which was 123% higher than that in the initial medium. In addition, in order to guide scale-up for production, logistic and Luedeking–Piret equations were proposed to predict the cell growth and antifungal compounds production. The fermentation kinetics and empirical equations of the coefficients (X0, Xm, μm, α, and β) for the two models were reported, which will aid the design and optimization of industrial processes. The degrees of fit between calculated values of the model and the experimental data were 0.989 and 0.973, respectively. The results show that the cell growth and product synthesis models established in this study may better reflect the dynamic process of antifungal compounds production and provide a theoretical basis for further optimization and on-line monitoring of the fermentation process. [ABSTRACT FROM AUTHOR]

In twenty-first century buildings, green roof systems are envisioned as great solution for improving Environmental sustainability in urban ecosystems and it helps to mitigate various health hazards for humans due to climatic pollution. This study determines the feasibility of using five domestic organic wastes, including sawdust, wood bark, biochar, coir, and compost, as sustainable substrates for green roofs as compared to classical Sri Lankan base medium (fertiliser + potting mix) in terms of physicochemical and biological parameters associated with growing mediums. Comprehensive methodologies were devised to determine the thermal conductivity and electric conductivity of growing mediums. According to preliminary experimental results, the most suitable composition for green roof substrates comprised 60% organic waste and 40% base medium. Sawdust growing medium exhibited the highest moisture content and minimum density magnitudes. Biochar substrate was the best performing medium with the highest drought resistance and vegetation growth. The wood bark substrate had the highest thermal resistance. Growing mediums based on compost, sawdust, and coir produced the best results in terms of nitrate, phosphate, pH, and electric conductivity (EC) existence. This study provided a standard set of comprehensive comparison methodologies utilising physicochemical and biological properties required for substrate characterization. The findings of this research work have strong potential in the future to be used in selecting the most suitable lightweight growing medium for a green roof based on stakeholder requirements. [ABSTRACT FROM AUTHOR]

Increased production of renewable energy sources is becoming increasingly needed. Amidst other strategies, one promising technology that could help achieve this goal is biological hydrogen production. This technology uses micro-organisms to convert organic matter into hydrogen gas, a clean and versatile fuel that can be used in a wide range of applications. While biohydrogen production is in its early stages, several challenges must be addressed for biological hydrogen production to become a viable commercial solution. From an experimental perspective, the need to improve the efficiency of hydrogen production, the optimization strategy of the microbial consortia, and the reduction in costs associated with the process is still required. From a scale-up perspective, novel strategies (such as modelling and experimental validation) need to be discussed to facilitate this hydrogen production process. Hence, this review considers hydrogen production, not within the framework of a particular production method or technique, but rather outlines the work (bioreactor modes and configurations, modelling, and techno-economic and life cycle assessment) that has been done in the field as a whole. This type of analysis allows for the abstraction of the biohydrogen production technology industrially, giving insights into novel applications, cross-pollination of separate lines of inquiry, and giving a reference point for researchers and industrial developers in the field of biohydrogen production. [ABSTRACT FROM AUTHOR]

Geobacillus spp. are moderate thermophiles that can efficiently produce recombinant proteins. Considering the protein production exhibited by these species, we searched for robust promoters in Geobacillus kaustophilus HTA426. Transcriptome data revealed that several genes were highly expressed during the proliferative phase; their promoters were characterized using reporter assays with Venus fluorescent protein (VFP). The results suggested that the cspD promoter (PcspD) directed robust vfp expression at 60°C in G. kaustophilus. Although cspD potentially encodes a cold-shock protein, PcspD functioned at elevated temperatures. The promoter strongly functioned even in Escherichia coli; this prevented the cloning of some genes (e.g., vfp) downstream of it on a plasmid vector via E. coli-based genetic manipulation. Consequently, we generated a mutated PcspD that functioned inefficiently in E. coli and constructed the pGKE124 plasmid using the mutant promoter. The plasmid could carry vfp in E. coli and afford the production of VFP in G. kaustophilus at a yield of 390 mg/L. pGKE124 directed a similar production in other thermophilic species; the highest yield was observed in Geobacillus thermodenitrificans K1041. Several proteins could be produced using a system involving G. thermodenitrificans K1041 and pGKE124. Notably, the extracellular production of xylanase at a yield of 1 g/L was achieved using this system. Although the leaky production of nonsecretory proteins was observed, we developed a simple process to collectively purify recombinant proteins from the intracellular and extracellular fractions. The findings presented there propose an effective host–vector system for the production of recombinant proteins at elevated temperatures. Key points: • A thermophilic system to produce recombinant proteins was constructed. • The system produced diverse proteins using inexpensive media at elevated temperatures. • The system produced an extracellular protein at a yield of 1 g/L of culture. [ABSTRACT FROM AUTHOR]

Food waste is a major issue, with one-third of food wasted yearly. This study aimed to produce sustainably the industrial enzyme alpha-amylase using discarded bread waste. Brown (BBW) and white bread waste (WBW) were tested as growth substrates using solid-state and submerged fermentation. The biosynthesized α- amylase is applied to treat starch-heavy industrial wastewater and for textile desizing. Bacillus amyloliquefaciens showed the highest starch hydrolysis and enzyme activity on solid and liquid media. α-amylase production by B. amyloliquefaciens was optimized via a one-factor-at-a-time evaluation of production parameters. Optimal production occurred by submerged fermentation of BBW inoculated with 2% B. amyloliquefaciens at 37 °C and 200rpm for 24 h, reaching 695.2 U/mL α- amylase. The crude enzyme was immobilized on calcium alginate beads with 96.6% efficiency and kept 88.5% activity after 20 reuses, enhancing stability. A Box–Behnken design (BOX) assessed variable interactions. Response surface methodology (RSM) generated a quadratic model and analysis of variance (ANOVA analysis) fitting experimental starch hydrolysis data. Optimal conditions were pH 9, 45 °C, 70% starch, and 27.5 U/mL enzyme incubated for 15 min of contact time, with a high R2 of 0.83. ANOVA confirmed the enzyme's alkaliphilic and thermophilic nature. Using enzyme concentrations ranging from 10.9 to 695.1 U/mL, the enzyme desized textiles in 15 min at pH 9.0 and 45 °C with 96.3% efficiency. Overall, the optimized α- amylase from bread waste has industrial potential for sustainable starch processing. [ABSTRACT FROM AUTHOR]

This review aimed to show that bioherbicides are possible in organic agriculture as natural compounds from fungi and metabolites produced by them. It is discussed that new formulations must be developed to improve field stability and enable the commercialization of microbial herbicides. Due to these bottlenecks, it is crucial to advance the bioprocesses behind the formulation and fermentation of bio-based herbicides, scaling up, strategies for field application, and the potential of bioherbicides in the global market. In this sense, it proposed insights for modern agriculture based on sustainable development and circular economy, precisely the formulation, scale-up, and field application of microbial bioherbicides. [ABSTRACT FROM AUTHOR]

Succinic acid (SA) production from fermentation has drawn great interest owing to its simplicity and environmentally friendly process, but it is constrained by high downstream processing costs. The Pickering emulsion liquid membrane (PELM) process containing synergistic carriers (Aliquat 336 and trioctylamine (TOA)) in palm oil is an attractive technology for SA recovery from fermentation broths. The synergistic extraction mechanism was investigated using reactive extraction and the method of slope analysis. Almost 100% of SA was extracted from a 10 g/L simulated solution with a synergistic coefficient of 640. Based on the individual and mixed carrier investigations, it infers that Aliquat 336 and TOA function as base and synergist carriers, respectively. The stability of water-in-oil-in-water (W/O/W) emulsion was studied by varying the agitation speed, Span 80 concentration, and mixed surfactant concentration (Tween 80 and Span 80). At the best stability condition of 5% w/v (Span 80 + Tween 80), hydrophilic–lipophilic balance 6, 300 rpm agitation speed, 0.1% w/v Fe2O3 nanoparticles, 0.1 M Aliquat 336 + 0.1 M TOA, and 1.0 M sodium hydroxide, the emulsion was stable, and almost 100% of SA was extracted and enriched five times in the internal phase. The concentration limit of SA during its recovery by ELM is 10 g/L. Meanwhile, the results from water phase separation and droplet image proved that PELM has the advantage of rapid and efficient demulsification performance, where the demulsification can be completed within 5 min. Hence, synergistic PELM is a new class of ELM for the recovery of SA and it may be extended for downstream and bio-based manufacturing. [ABSTRACT FROM AUTHOR]

Food waste is a major issue, with one-third of food wasted yearly. This study aimed to produce sustainably the industrial enzyme alpha-amylase using discarded bread waste. Brown (BBW) and white bread waste (WBW) were tested as growth substrates using solid-state and submerged fermentation. The biosynthesized α- amylase is applied to treat starch-heavy industrial wastewater and for textile desizing. Bacillus amyloliquefaciens showed the highest starch hydrolysis and enzyme activity on solid and liquid media. α-amylase production by B. amyloliquefaciens was optimized via a one-factor-at-a-time evaluation of production parameters. Optimal production occurred by submerged fermentation of BBW inoculated with 2% B. amyloliquefaciens at 37 °C and 200rpm for 24 h, reaching 695.2 U/mL α- amylase. The crude enzyme was immobilized on calcium alginate beads with 96.6% efficiency and kept 88.5% activity after 20 reuses, enhancing stability. A Box–Behnken design (BOX) assessed variable interactions. Response surface methodology (RSM) generated a quadratic model and analysis of variance (ANOVA analysis) fitting experimental starch hydrolysis data. Optimal conditions were pH 9, 45 °C, 70% starch, and 27.5 U/mL enzyme incubated for 15 min of contact time, with a high R2 of 0.83. ANOVA confirmed the enzyme's alkaliphilic and thermophilic nature. Using enzyme concentrations ranging from 10.9 to 695.1 U/mL, the enzyme desized textiles in 15 min at pH 9.0 and 45 °C with 96.3% efficiency. Overall, the optimized α- amylase from bread waste has industrial potential for sustainable starch processing. [ABSTRACT FROM AUTHOR]

Fermentation is thought to be born in the Fertile Crescent, and since then, almost every culture has integrated fermented foods into their dietary habits. Originally used to preserve foods, fermentation is now applied to improve their physicochemical, sensory, nutritional, and safety attributes. Fermented dairy, alcoholic beverages like wine and beer, fermented vegetables, fruits, and meats are all highly valuable due to their increased storage stability, reduced risk of food poisoning, and enhanced flavor. Over the years, scientific research has associated the consumption of fermented products with improved health status. The fermentation process helps to break down compounds into more easily digestible forms. It also helps to reduce the amount of toxins and pathogens in food. Additionally, fermented foods contain probiotics, which are beneficial bacteria that help the body to digest food and absorb nutrients. In today's world, non-communicable diseases such as cardiovascular disease, type 2 diabetes, cancer, and allergies have increased. In this regard, scientific investigations have demonstrated that shifting to a diet that contains fermented foods can reduce the risk of non-communicable diseases. Moreover, in the last decade, there has been a growing interest in fermentation technology to valorize food waste into valuable by-products. Fermentation of various food wastes has resulted in the successful production of valuable by-products, including enzymes, pigments, and biofuels. [ABSTRACT FROM AUTHOR]

Thermophilic cell factories have remarkably broad potential for industrial applications, but are limited by a lack of genetic manipulation tools and recalcitrance to transformation. Here, we identify a thermophilic type I-B CRISPR-Cas system from Parageobacillus thermoglucosidasius and find it displays highly efficient transcriptional repression or DNA cleavage activity that can be switched by adjusting crRNA length to less than or greater than 26 bp, respectively, without ablating Cas3 nuclease. We then develop an orthogonal tool for genome editing and transcriptional repression using this type I-B system in both thermophile and mesophile hosts. Empowered by this tool, we design a strategy to screen the genome-scale targets involved in transformation efficiency and established dynamically controlled supercompetent P. thermoglucosidasius cells with high efficiency (~ 108 CFU/μg DNA) by temporal multiplexed repression. We also demonstrate the construction of thermophilic riboflavin cell factory with hitherto highest titers in high temperature fermentation by genome-scale identification and combinatorial manipulation of multiple targets. This work enables diverse high-efficiency genetic manipulation in P. thermoglucosidasius and facilitates the engineering of thermophilic cell factories. Thermophilic genetic manipulation tools are limited. Here the authors report a thermophilic type I-B CRISPR-Cas system and show it displays efficient transcriptional repression or DNA cleavage activity: they develop a tool for genome editing and transcriptional repression in both thermophile and mesophile hosts. [ABSTRACT FROM AUTHOR]

The present work aims to exploit the zero-cost inducer bread waste (BW) for the production of cold-adapted α-amylase (CA-AM21) by the hyperproducer marine psychrotolerant Glutamicibacter soli strain AM6 EMCCN 3074. Incubation temperature (20 °C), incubation time, BW, (NH4)2SO4, and modified seawater-based minimal medium were inferred to be significant factors influencing CAM-21 production in OVAT and Plackett-Burman investigations. BW (3.8%w/v), (NH4)2SO4 (0.098%w/v), and incubation time (2.329 days) prompted CA-AM21 (56.85 U/mL) with 7.58-fold enhancement, Box-Behnken design, and ridge steepest ascent path inferences. A two-step strategy was used to purify CA-AM21: fractional (NH4)2SO4 precipitation (60-80%) and a starch affinity chromatography. Specific activity, yield, and fold purification of purified CA-AM21 were 884.5 U/mg, 12.45%, and 285.3, respectively. CA-AM21 exhibited an approximate molecular mass of 14 kDa, deduced from SDS-PAGE analyses. The pH and temperature optimums for CA-AM21 were 7.0 and 40 °C, respectively. At 5–25 °C, full activity was maintained after 2 h. At pH 6.0–8.0, almost full activity (90–100%) was retained after 15 h. CA-AM21 demonstrated full stability after 30 min at 1.0–5.0 M NaCl, with 200% increased activity at 1.0–4.0 M NaCl. Full stability of CA-AM21 in the presence of non-ionic detergents, such as Tween 20, Tween 80, and Triton X-100, with 100% activity sustained after 30 min was retained. On soluble starch, purified CA-AM21 exhibited km and Vmax of 0.039 mg.mL−1 and 115.71 μmol glucose. min−1. mg−1, respectively. The purified CA-AM21 demonstrated remarkable significant washing efficiency with commercial laundry detergents thus implying its applicability for detergent formulations. [ABSTRACT FROM AUTHOR]

In this study, biodiesel was produced from high free fatty acid (FFA) oil obtained from waste olives, whose food quality deteriorated by falling from the tree to the ground. The FFA value of the oil obtained from waste olives was determined as 23% by titration method. In order to produce biodiesel with high conversion efficiency, esterification process was carried out to reach at least 1% FFA value in the first stage of the study. Acid esterification experiments were designed according to Taguchi's L16 (42 21) orthogonal array. The amount of sulfuric acid catalyst, methanol ratio, and mixing speed were taken as the test variables for the esterification process. For the lowest FFA value, optimum test parameters were determined using the signal-to-noise (S/N) ratio. In the biodiesel production stage, ultrasound-assisted transesterification method was preferred in terms of high conversion efficiency and short reaction duration. According to the results, it was determined that the optimum reaction conditions in the esterification process were 25% by weight acid catalyst (according to the weight of the FFA in the oil), 22:1 methanol molar ratio in terms of fatty acids, and 400 rpm mixing speed. At these reaction conditions, the FFA of the oil was reduced from 23 to 0.608% in a single step. In the ultrasound-assisted process, Waste olive oil methyl ester (WOOME) conversion yield of 98.7% was achieved in a reaction time of 10 min. The fuel properties of WOOME (also called biodiesel) were determined to be within the EN 14214 standard. As a result, optimization was made to minimize the use of alcohol and catalyst in the acid esterification process. Also, time and energy savings were achieved in biodiesel production with ultrasound-assisted. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the use of ethanol/gasoline fuel blends in a single-cylinder spark-ignition engine with energy, exergy, exergoeconomic and exergoenvironmental analysis. Test fuels (G100, E10, E20, E30, E40, E50, and E100) prepared by adding ethanol obtained from agricultural products to gasoline at different ratios were utilized in experimental studies. Thermodynamic analyses were carried out using the performance and emission data obtained from the engine tests. Thermal efficiency and exergy efficiencies were computed with energy and exergy analyses. The highest efficiencies were acquired at 2500 rpm for all fuels. The exergy efficiency of G100, E20 and E40 fuels at this engine speed is 17.13%, 15.81% and 14.62%, respectively. Furthermore, cost of engine shaft work in exergoeconomic analysis and environmental cost of shaft work in exergoenvironmental analysis were found in study. When an engine speed was 2500 rpm in E50 fuel, the cost of shaft work was 74.21 $ MJ−1, and the environmental cost of shaft work was 59.07 $ GJ−1. Moreover, exergoeconomic factor and exergoenvironmental factor values of fuel blends were computed. It was revealed that increased ethanol ratio in fuel blends increased economic and environmental costs. In terms of economy and environment, it can be considered appropriate that the ethanol ratio in fuel blends is between 30 and 40%. If ethanol is used higher than these rates, costs increase and fuels become uneconomical. [ABSTRACT FROM AUTHOR]

Waste material generated from food sources contributes a significant percentage of the waste generated worldwide. However, it is believed that about two-thirds of food is wasted globally. Anaerobic digestion methods have established important prospects in the field of food waste treatment. Obviously, it can produce significant amounts of energy and can remove a significant proportion of the organics. Microalgae represent a promising option for recycling waste nutrients from different types of food waste that can reduce the cost of producing different value-added products. The process of cultivating microalgae in anaerobic digestate from food waste fulfills the two objectives of environmental policy, i.e., treatment and recovery. This review focuses on the cultivation of microalgae in wastewater from the anaerobic digestate of food waste and the extraction of different value-added products from the biomass of microalgae. [ABSTRACT FROM AUTHOR]

In Southern California, irrigation infrastructure is a prerequisite for urban green space management, and valve boxes are installed widely to manage water flow. These below-ground, plastic boxes protect valves and manifolds, create space for connecting pipes, and present a scarce ecological resource—elevated humidity and shelter from potential predators. We provide the first systematic survey of the biodiversity of valve boxes and evaluate their role in the establishment of non-native species. We conducted comprehensive surveys of slug and spider refugial habitat elements, including leaf litter, crevices, decaying logs and other cover objects, and valve boxes, across urban Greater Los Angeles and adjacent wildland areas. We found that valve boxes comprised nearly all of the surveyed habitat for three common non-native species, including two slugs in the genus Ambigolimax and a spider in the genus Steatoda. At 83 of 85 sites, we detected these species only in valve boxes and not in any other habitat elements. While valve boxes were significantly more frequent in urban than wildland areas, detections in wildland areas were also largely restricted to valve boxes. All of these species share a preference for elevated levels of humidity, and we speculate that introduced slug and spider taxa within irrigation infrastructure may be a general feature of many urban areas, especially in relatively xeric climates with locally high densities of valve boxes. Under these conditions, irrigation infrastructure likely facilitates the establishment and persistence of non-native species requiring high humidity throughout the urbanized world, and could contribute to their cosmopolitan distribution. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) is a promising energy carrier owing to its environmentally friendly properties and high energy content. The aim of this work is to achieve a continuous H2 production from a simplified culture medium composed of date wastes (DW) and natural seawater using the marine bacterium, Thermotoga maritima. Increasing the dilution rate (D) from 0.02 to 0.25 h− 1 in the continuous stirred tank reactor (CSTR) improved the volumetric H2 production rate (QH2) from 2 to 17 mmol/L.h. At a D above 0.25 h− 1, a washout of the bacterium cells was observed, resulting in a significant decrease of biomass concentration (BC) and then the drop in QH2. The production of H2 was improved by using a membrane bioreactor (MBR) due to the cell retention in the reactor. At a high D of 0.6 h− 1, the maximum QH2 was increased from 0.6 to 61.75 mmol/L.h, which is higher than those previously reported on continuous H2 production from different substrates. Moreover, increasing the hexose equivalent concentration in the date juice (DJ) from 30 to 60 mmol/L further enhanced the H2 production. It allowed a QH2 of 70.2 mmol/L.h which is interesting for a large scale production of H2 from date wastes. [ABSTRACT FROM AUTHOR]

Employing aerobic fermentation, Gram-negative bacteria belonging to the genus Xanthomonas produce the high molecular weight natural heteropolysaccharide known as xanthan. It has various amounts of O-acetyl and pyruvyl residues together with D-glucosyl, D-mannosyl, and D-glucuronyl acid residues in a molar ratio of 2:2:1. The unique structure of xanthan allowed its various applications in a wide range of industries such as the food industry, pharmacology, cosmetics and enhanced oil recovery primarily in petroleum. The cultivation medium used in the manufacture of this biopolymer is critical. Many attempts have been undertaken to generate xanthan gum from agro-based and food industry wastes since producing xanthan gum from synthetic media is expensive. Optimal composition and processing parameters must also be considered to achieve an economically viable manufacturing process. There have been several attempts to adjust the nutrient content and feeding method, temperature, pH, agitation and the use of antifoam in xanthan fermentations. Various modifications in technological approaches have been applied to enhance its physicochemical properties which showed significant improvement in the area studied. This review describes the biosynthesis production of xanthan with an emphasis on the importance of the upstream processes involving medium, processing parameters, and other factors that significantly contributed to the final application of this precious polysaccharide. [ABSTRACT FROM AUTHOR]

Humans are transforming natural habitats into managed urban green areas and impervious surfaces at an unprecedented pace. Yet the effects of human presence per se on animal life-history traits are rarely tested. This is particularly true in cities, where human presence is often indissociable from urbanisation itself. The onset of the SARS-CoV-2 outbreak, along with the resulting lockdown restrictions, offered a unique, "natural experiment" to investigate wildlife responses to a sudden reduction in human activity. We analysed four years of avian breeding data collected in a European capital city to test whether lockdown measures altered nestbox occupancy and life-history traits in terms of egg laying date, incubation duration and clutch size in two urban adapters: great tits (Parus major) and blue tits (Cyanistes caeruleus). Lockdown measures, which modulated human presence, did not influence any of the life-history traits investigated. In contrast, the interaction between year and tree cover, a distinct ecological attribute of the urban space, was positively associated with clutch size, a key avian life-history and reproductive trait. This highlights the importance of inter-year variation and habitat quality over human activity on urban wildlife reproduction. We discuss our results in the light of other urban wildlife studies carried out during the pandemic, inviting the scientific community to carefully interpret all lockdown—associated shifts in biological traits. [ABSTRACT FROM AUTHOR]

The vegan food industry is gaining popularity nowadays. Ganoderma sp. is mainly used in the health and food industries as a medicinal, edible mushroom with high nutritional potential. Through two-stage cultivation methods, the study optimized the production of mycelial pellets for vegetarian food. When soybean powder was used as an alternative to egg yolk powder to meet vegetarian requirements, the number of pellets increased from 1100 to 1800 particles/dL, however, the pellet diameter reduced up to 22% (3.2–2.6 mm). The culture was expanded to the second stage using the Taguchi method coupled with Plackett-Burman Design and quantification by ImageJ software for enlarging pellets size. The optimal conditions were 10 mL of the first-stage broth inoculum, yeast powder (0.5 g/dL), glucose (0.5 g/dL), and MgSO4 (0.2 g/dL) at 100 rpm in the dark for 7 days. In 500 mL pilot scale production, the biomass yield was 0.31 g/dL and 3400 mycelium pellets/dL with a 5.2 mm diameter with appearance characteristics suitable for direct development as food. The study may help to develop a novel pellet food of filamentous fungi for the vegetarian market. [ABSTRACT FROM AUTHOR]

Cakes are bakery goods that are frequently discarded. Cake leftovers are mostly carbs with a significant potential for sugar recovery using subcritical water hydrolysis; a clean, rapid, and sustainable approach. This study aimed to evaluate the highest sugar that could be recovered from cake leftovers using subcritical water hydrolysis. The cake leftovers were hydrolyzed in a batch-type subcritical water reactor at the process conditions of 160°C − 200°C, process time (5−15 minutes), and solid loading (10% − 50%). The yields of total sugar and reducing sugar rose parallelly to the process conditions. The optimal process parameters for sugar recovery of the cake leftovers were 200°C, 15 minutes, and 50%, yielding a total sugar yield of 0.895 mg/ml and a reducing sugar yield of 0.700 mg/ml. Hydrolysis of the carbohydrates resulted in sucrose, glucose, fructose, galactose, xylose, and mannose. Results from the scanning electron microscope (SEM) demonstrated that at higher temperatures (200℃), the surface of cake leftovers looked to be considerably changed. This study has set the framework for future research into the uses and benefits of subcritical water hydrolysis. [ABSTRACT FROM AUTHOR]

Today, additives with high oxygen content are added to gasoline to reduce its environmental damages. Alcohols are the most important ones among them. Short-chain alcohols such as methanol and ethanol are preferred for gasoline engines; however, a limited number of studies where long-chain alcohols are used were carried out. In this study, the engine performance and exhaust emission values were determined using gasoline, PEN25 (25% 1-pentanol + 75% gasoline), HEX25 (25% 1-hexanol + 75% gasoline), and HEP25 (25% 1-heptanol + 75% gasoline) in a four-stroke spark-ignition engine (SIE) with single cylinder and water cooling under constant speed (1500 rpm) and different load conditions (4, 8, 12, and 16 kg). The energy, exergy, economical, environmental, and sustainability parameters were analyzed based on the obtained data. Finally, it was concluded that the addition of different heavy alcohols to gasoline increases fuel consumption and reduces thermal efficiency. Due to the low energy content of alcohols, the energy and exergy efficiencies of blended fuels were lower than that of gasoline. At full load, the thermal efficiencies of gasoline, PEN25, HEX25, and HEP25 were found to be 37.36%, 28.27%, 31.92%, and 34.84%, respectively; meanwhile, the exergy efficiencies were in the order of 34.83%, 26.53%, 29.96%, and 32.70%. Although the economical analyses were affected adversely since alcohol prices are higher than gasoline prices, it was found that fuel blends gave better results than gasoline in terms of environmental aspect. The net work cost values of gasoline, PEN25, HEX25, and HEP25 was calculated to be 86.76%, 84.99%, 85.64%, and 85.39%, respectively. If the production of heavy alcohols is increased, then their prices may decrease. This is one of the priority objectives for heavy alcohols being an alternative additive for gasoline. [ABSTRACT FROM AUTHOR]

Parageobacillus thermoglucosidasius is a thermophilic bacterium characterized by rapid growth, low nutrient requirements, and amenability to genetic manipulation. These characteristics along with its ability to ferment a broad range of carbohydrates make P. thermoglucosidasius a potential workhorse in whole-cell biocatalysis. The phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) catalyzes the transport and phosphorylation of carbohydrates and sugar derivatives in bacteria, making it important for their physiological characterization. In this study, the role of PTS elements on the catabolism of PTS and non-PTS substrates was investigated for P. thermoglucosidasius DSM 2542. Knockout of the common enzyme I, part of all PTSs, showed that arbutin, cellobiose, fructose, glucose, glycerol, mannitol, mannose, N-acetylglucosamine, N-acetylmuramic acid, sorbitol, salicin, sucrose, and trehalose were PTS-dependent on translocation and coupled to phosphorylation. The role of each putative PTS was investigated and six PTS-deletion variants could not grow on arbutin, mannitol, N-acetylglucosamine, sorbitol, and trehalose as the main carbon source, or showed diminished growth on N-acetylmuramic acid. We concluded that PTS is a pivotal factor in the sugar metabolism of P. thermoglucosidasius and established six PTS variants important for the translocation of specific carbohydrates. This study lays the groundwork for engineering efforts with P. thermoglucosidasius towards efficient utilization of diverse carbon substrates for whole-cell biocatalysis. [ABSTRACT FROM AUTHOR]

Biohydrogen possesses similar benefits as the other types of biofuels in terms of its capability to reduce fossil fuel dependency and greenhouse gas emission. This work investigates the economic potential of biohydrogen production using liquid pineapple waste as the feedstock. The economic assessment conducted includes total production cost, total annual sales, annual profit analysis, and cash flow analysis focusing on biohydrogen production via integrated dark and photo fermentation. The estimated Total Capital Investment involved in the production of 3000 metric tonnes of biohydrogen annually from liquid pineapple waste is RM114,994,456 with the net annual profit after tax of RM68,659,386. The plant would operate for 20 years with a depreciation of 10%. For 0% undiscounted cash flow, the payback period is 5.25 years while the expected rate of return is 68%. The economic analysis presented in this work supports the economic feasibility of biohydrogen production from liquid pineapple waste in large scale making it more desirable as another important player in achieving circular economy. [ABSTRACT FROM AUTHOR]

Global warming is emerging as the most serious concern for the planet, with greenhouse gas emissions (GHG) contributing considerably to the problem. Consequently, warranting energy sustainability has turned into an urgent issue for scholars and policy-makers alike. Bioethanol has emerged as a viable eco-friendly replacement for avoiding GHG generating fossil fuels. However, bioethanol has faced several hurdles that have discouraged its development during these years. Apart from unpractical technological applications and failed ventures, bioethanol has been experiencing heavy competition from hydrocarbon fuels and adverse economic cycles. Currently, bioethanol is facing an uncertain scenario due to the combination of climbing crop prices and slow innovative production processes, including the cost-effective utilization of agriculture waste. Here, the impact of market conditions upon the competitive development of bioethanol is analyzed. It is argued that fluctuating fossil fuel prices over the last ten years has discouraged bioethanol's technological viability. As a result, the consolidation of industrial biotechnology, especially for biorefineries, has slowed down. Policy implications of recurrent fluctuations in the bioethanol market are also discussed. [ABSTRACT FROM AUTHOR]

This study aims to perform kinetic and thermodynamic analysis of subcritical water hydrolysis (SWH) of bakery leftovers. Hydrolysis kinetics of leftover croissants (LC) and leftover doughnuts (LD) into monosaccharides and by-product (hydroxymethylfurfural, HMF), via subcritical water hydrolysis, were studied in temperature range of 100 to 240°C for 6 to 30 minutes and solid loading of 10% (w/v). The monosaccharides yield increased from 100 to 200°C, but it decreased when the temperature further increased from 220–240°C due to degradation of monosaccharides into its by-product (HMF). The activation energy (Ea) monosaccharides degradation was higher than its formation: 104.87 and 88.55 kJ/mol (LC) and 104.69 and 75.72 kJ/mol (LD). The positive values of ΔG# signified that the SWH for sugar recovery from LC and LD is an endergonic reaction. [ABSTRACT FROM AUTHOR]

The potential of bioethanol generation using the mixture of waste French fries (WFF) and municipal wastewater (MWW) via separate hydrolysis and fermentation (SHF) was evaluated in this study. The effect of WFF substrate loading (SL, 10%, 16%, and 20%, w/v) on the SHF was also examined. Both glucose production and hydrolysis efficiency increased with increasing of SL from 10 to 16% and the maximum glucose yield of 0.236 g glucose/g WFF and hydrolysis efficiency of 91.9% were obtained at SL of 16%. However, the glucose production and hydrolysis efficiency decreased when the SL further increased to 20% due to the inhibition on enzyme caused by higher glucose production. The mixture hydrolysate was then used as feedstock for ethanol fermentation. The maximum ethanol production of 22.69 g/L was obtained from SL of 16%. The highest rate of glucose conversion to ethanol was 84.2%. The results demonstrated that the mixture of WFF and MWW could be used for ethanol production by the SHF. [ABSTRACT FROM AUTHOR]

Bread as a staple food has been predominantly prepared from refined wheat flour. The world's demand for food is rising with increased bread consumption in developing countries where climate conditions are unsuitable for wheat cultivation. This reliance on wheat increases the vulnerability to wheat supply shocks caused by force majeure or man-made events, in addition to negative environmental and health consequences. In this review, we discuss the contribution to the sustainability of food systems by partially replacing wheat flour with various types of plant ingredients in bread making, also known as composite bread. The sustainable sources of non-wheat flours, their example use in bread making and potential health and nutritional benefits are summarized. Non-wheat flours pose techno-functional challenges due to significantly different properties of their proteins compared to wheat gluten, and they often contain off-favor compounds that altogether limit the consumer acceptability of final bread products. Therefore, we detail recent advances in processing strategies to improve the sensory and nutritional profiles of composite bread. A special focus is laid on fermentation, for its accessibility and versatility to apply to different ingredients and scenarios. Finally, we outline research needs that require the synergism between sustainability science, human nutrition, microbiomics and food science. [ABSTRACT FROM AUTHOR]

In the scenario of alarming increase in greenhouse and toxic gas emissions from the burning of conventional fuels, it is high time that the population drifts towards alternative fuel usage to obviate pollution. Hydrogen is an environment-friendly biofuel with high energy content. Several production methods exist to produce hydrogen, but the least energy intensive processes are the fermentative biohydrogen techniques. Dark fermentative biohydrogen production (DFBHP) is a value-added, less energy-consuming process to generate biohydrogen. In this process, biohydrogen can be produced from sugars as well as complex substrates that are generally considered as organic waste. Yet, the process is constrained by many factors such as low hydrogen yield, incomplete conversion of substrates, accumulation of volatile fatty acids which lead to the drop of the system pH resulting in hindered growth and hydrogen production by the bacteria. To circumvent these drawbacks, researchers have come up with several strategies that improve the yield of DFBHP process. These strategies can be classified as preliminary methodologies concerned with the process optimization and the latter that deals with pretreatment of substrate and seed sludge, bioaugmentation, co-culture of bacteria, supplementation of additives, bioreactor design considerations, metabolic engineering, nanotechnology, immobilization of bacteria, etc. This review sums up some of the improvement techniques that profoundly enhance the biohydrogen productivity in a DFBHP process. [ABSTRACT FROM AUTHOR]

Vine shoots and surplus grape must were assessed as feedstocks for succinic acid production with Actinobacillus succinogenes and Basfia succiniproducens. After acidic and enzymatic hydrolysis, vine shoots released 35–40 g/L total sugars. Both bacterial species produced 18–21 g/L succinic acid from this hydrolysate in 120 h. Regarding grape must fermentation, A. succinogenes clearly outperformed B. succiniproducens. Yeast extract (a source of organic nitrogen and vitamins) was the only additional nutrient needed by A. succinogenes to grow on grape must. Under mathematically optimized conditions (145.7 g/L initial sugars and 24.9 g/L yeast extract), A. succinogenes generated 88.9 ± 1.4 g/L succinic acid in 96 h, reaching a succinic acid yield of 0.66 ± 0.01 g/g and a sugar consumption of 96.64 ± 0.30%. Substrate inhibition was not observed in grape musts with 125–150 g/L initial sugars, provided that an adequate amount of yeast extract was available for bacteria. Alternative nitrogen sources to yeast extract (red wine lees, white wine lees, urea, NH4Cl, and choline chloride) were not suitable for A. succinogenes in grape must. Key Points: • Vine shoots and surplus grape must were assessed for succinic acid bioproduction. • Succinic acid bioproduction was 21 g/L with vine shoots and 89 g/L with grape must. • Fermentation was efficient at high sugar loads if organic N supply was adequate. [ABSTRACT FROM AUTHOR]

The use of waste stream residues as feedstock for material production simultaneously helps reduce dependence on fossil-based resources and to shift toward a circular economy. This study explores the conversion of food waste into valuable chemicals, namely, bio-pigments. Here, a simulated food waste feedstock was converted into pigments via solid-state fermentation with the filamentous fungus Talaromyces albobiverticillius (NRRL 2120). Pigments including monascorubrin, rubropunctatin, and 7-(2-hydroxyethyl)-monascorubramine were identified as products of the fermentation via ultra-performance liquid chromatography coupled with quadrupole-time-of-flight electrospray ionization mass spectrometry. Pigments were obtained at concentrations of 32.5, 20.9, and 22.4 AU/gram dry substrate for pigments absorbing at 400, 475, and 500 nm, respectively. Pigment production was further enhanced by co-culturing T. albobiverticillius with Trichoderma reesei (NRRL 3652), and ultimately yielded 63.8, 35.6, and 43.6 AU/gds at the same respective wavelengths. This represents the highest reported production of pigments via solid-state fermentation of a non-supplemented waste stream feedstock. Key points: • Simulated food waste underwent solid-state fermentation via filamentous fungi. • Bio-pigments were obtained from fermentation of the simulated food waste. • Co-culturing multiple fungal species substantially improved pigment production. [ABSTRACT FROM AUTHOR]

Increasing world's population, rapid urbanization, and modern lifestyle results in enormous generation of food bio-residues and wastes from various agricultural, household, and industrial activities. Approximately one-third of the total food produced is lost/wasted every year, according to the Food and Agriculture Organization (FAO) that represents a significant threat to food systems sustainability and environment. Multi-faceted and state-of-the-art solutions are continuously being explored and executed by research scientists, food industries, and government/non-government organizations to address the social, economic, and environmental concerns, depleted fossil fuel resources and climate change. Discarded food waste and bio-residues are enriched with a plethora of high-value biomolecules, such as Carbohydrates, lipids, lignin-based molecules, and proteins. These compounds are thought to exhibit a vast economic potential for transforming into a range of revenue sources, such as biofuels, biopolymers, organic acids, enzymes, nutraceuticals, and functional sugars etc. Enzyme-assisted bio-transformations have been stepped up as a sustainable valorization way for the effective treatment of such food waste. This approach is capable of efficient conversion of lignin-based food bio-residues into a large number of high-value bioproducts and industrial commodities given excellent catalytic performance, eco-sustainability, process stability, and amenability to commercial utility. This review spotlights recent and state-of-art information about food waste as a growing environmental burden, current practices, and enzyme-based valorization approaches to convert food waste into marketable products, including biofuels, prebiotics, biodegradable plastics, sweeteners, bioactive compounds, rare functional sugars, biosurfactants, etc. Current challenges, conclusive remarks, and future bioeconomy prospects are also discussed to accomplish the target goals of sustainable industrial production along with food waste minimization. In conclusion, enzymes' deployment might constitute an eco-friendly and sustainable solution for food waste management by producing high-value products. [ABSTRACT FROM AUTHOR]

Phenolic compounds of breads added with turmeric at different concentrations (A: 0, B: 1.25, C: 2.5, D: 5 and E:10%) and radiated by UV-C (I. 0, II. 15, III. 30 and IV. 60 s), have been evaluated by HPLC (High-performance liquid chromatography). It is shown that: (i) UV-C radiation modifies the content of phenolic compounds as a function of the percentage of addition of turmeric and the exposure time. There were significant differences (ρ ≤ 0.05) in the concentration of phenolic acids of the turmeric bread (TB): 0 s (sinapic, chlorogenic, protocatechuic), 15 s (chlorogenic, ferulic, protocatechuic, p-hydroxybenzoic, gallic), 30 s (chlorogenic and gallic) and 60 s (chlorogenic). (ii) In TB without radiation appeared, the sinapic, beta resorcylic, syringic and ferulic acids. In the radiation of bread at 15 s, the phenolic acids chlorogenic, ferulic, protocatechuic, p-hydroxybenzoic, gallic, had the highest concentration in the breads added with turmeric at 10% (0.02 μg mL−1), 10% (0.38 μg mL−1), 1.25, 2.5, 5% (0.39 μg mL−1), 10% (1.06 μg mL −1) and 0% (1.10 μg mL−1). (iii) There was a degradation of phenolic acids due to UV-C radiation at 30 and 60 s. At 15 s radiation, sinapic, beta resorcylic, syringic and ferulic acids were not detected in turmeric breads from breads added with turmeric at (1.25, 1.25, 0 and 0%). In radiation at 60 s, beta resorcylic, syringic and ferulic acids were not detected in any bread added with turmeric. In addition, measurements of proximate chemistry, color, sensory analysis, and number of fungal colonies were performed. It is important to mention that the sanitary quality is improved by both UV-C radiation and turmeric. However, the highest results in sanitary quality improvement were due to turmeric. [ABSTRACT FROM AUTHOR]

Background: Wild cocoyam (Caladium bicolar) is non-edible starchy material which is commonly known as 'Ede umuagbara' in the south-east region of Nigeria. Evaluating the potential of wild cocoyam for citric acid production was investigated using Aspergillus niger in a submerged culture. Results: This study showed that wild cocoyam flour concentration, pretreatment of wild cocoyam, inoculums size, initial pH of wild cocoyam and incubation temperature of wild cocoyam medium had significant effect on the amount of citric acid produced from wild cocoyam (p < 0.05). Citric acid concentration increased as the concentration wild cocoyam increased up to 15% with the maximum citric acid concentration of 10.0 ± 0.251 g/l after 96 h of fermentation. Also citric acid concentration increased as the pretreatment time of wild cocoyam increased from 5 to 20 min. A 20 min pretreatment time at 121 °C was the optimum with maximum concentration of 14.0 ± 0.325 g/l citric acid after 96 h of fermentation. 15% inoculums was the optimum with the maximum concentration of 16.0 ± 0.431 g/l citric acid. However, the wild cocoyam initial pH value of 5.5 was the optimum for maximum citric acid concentration of 19.0 ± 0.316 after 96 h of fermentation. Moreover, citric acid concentration increased as the incubation temperature of wild cocoyam medium increased from 20 to 30 °C. Incubation of wild cocoyam medium at 30 °C was the optimum with the maximum citric acid concentration of 23.0 ± 0.432 g/l after 96 h of fermentation. Conclusion: Therefore, the result revealed that wild cocoyam which is found plenty within the south-east region of Nigeria can be converted to citric acid if well harnessed. [ABSTRACT FROM AUTHOR]

One-third of food produced for human consumption is lost as waste along the food supply chain. The food industry wastes contain carbohydrates, proteins, lipids, and lignocellulosic substances such as cellulose, hemicellulose, and lignin. These wastes are produced in large quantities worldwide and cause serious environmental problems. Due to the high concentration in organic and nutrient substances, food industry wastes are used for bioethanol production by microorganisms through various fermentation systems. The conversion of a lignocellulosic substance into bioethanol includes three steps: pretreatment, enzymatic hydrolysis, and fermentation. The problems concerning bioethanol production from food industry wastes are related to handling of biomass and application of pretreatment methods in order to improve the conversion of lignocellulosic materials into fermentable sugars. This review provides detailed overview and current knowledge on the pretreatment methods of lignocellulosic substances such as chemical (acid or alkaline, organic solvent), physical (milling, pyrolysis, microwave oven irradiation), physicochemical (steam explosion, hydrothermal processes, ammonia fiber explosion, CO2 explosion), and biological (fungi, bacteria). Pretreatment is followed by enzymatic hydrolysis with a mixture of suitable enzymes (mainly cellulase, β-glucosidase, pectinase) at 50 °C for 48 or 72 h. The production of bioethanol from food industry wastes is enhanced by enzymatic hydrolysis of the total polysaccharides into metabolizable sugars. The conversion of wastes from the food industry to the second generation ethanol is discussed in details. [ABSTRACT FROM AUTHOR]

This study is intended to determine the applicability of LPG systems with hybrid LPG technology which could not be applied before in vehicles with layered combustion system. No previous academic studies have been found in the literature on hybrid LPG system. This technology exists in the sector, but an academic gap has been filled with this study. For this purpose, Volkswagen Touran 1.6 FSI brand vehicle, which had a four-stroke, four-cylinder, direct injection, split intake manifold, layered combustion system gasoline engine with AKL brand hybrid LPG system, was used on a dynamometer and vehicle wheel power and exhaust emission values were measured according to DIN 70020 at different gear ranges and speeds. When the power values were examined, it was determined that there was approximately 10.23% power loss in LPG mode compared to gasoline mode. When gasoline and LPG fuels are evaluated in terms of energy values in liter basis use; this may result from the fact that LPG gives 30% less energy than gasoline, and secondly LPG fuel occupies more space because it enters the combustion chamber in gaseous phase with the air in the engine intake manifold. When the exhaust emission values are analyzed, it is seen that 8.25% and 71.76% less harmful emissions occur for CO2 and CO values in LPG mode compared to gasoline mode. It was also seen that, in HC values, there was 27.15% less emission in 3rd, 4th and 5th gear levels in LPG mode compared to gasoline mode; and there was 14.28% more emission in 6th gear level. When the changes of the lambda (λ) values are examined, it is observed that it occurs at a more ideal rate in the 3rd and 4th gear stages in LPG mode compared to gasoline mode, in the 5th and 6th gear. As a result, it was observed that hybrid LPG system can be applied on gasoline engines with layered combustion system and although there is a loss of power in terms of vehicle performance, it was concluded that the use of LPG was advantageous compared to the use of gasoline fuel regarding exhaust emissions. [ABSTRACT FROM AUTHOR]

Rising pollutants and greenhouse gas emissions from fossil fuels are serious environmental concerns that led to a tremendous focus of scientific research. The use of renewable resources as feedstock to produce fuels could help preserve the environment and offer economic and social sustainability. This preceded the development of alternative fuels such as biodiesel, and bioethanol. Over the last decade, the substantial expansion of biodiesel production indicates stoichiometrically increased crude glycerol co-production. Due to the surplus availability of the crude glycerol (as it does not find any potential application for complete utilisation), its market value has fallen and is even seen as a waste stream instead of a lucrative co-product. While high-purity glycerol is used in cosmetics, food, paints, and pharmaceutical industries for medicines, crude glycerol is an attractive organic carbon substrate to produce value-added products through microbial fermentation or physicochemical processing. The review discussed the recent developments in glycerol to produce fuels such as bioethanol, hydrogen, and methanol. Besides, it highlights the opportunities and challenges in utilising crude/waste glycerol generated from the biodiesel industry. [ABSTRACT FROM AUTHOR]

Purpose: This work aimed the food waste (FW) valorization by the production of fungal enzymes in solid-state fermentation (SSF) and a hydrolysate with the potential to obtain products with high added value. Methods: An original bioprocess based on Rhizopus oligosporus cultured by SSF using medium consisting of FW, sugarcane bagasse (SCB), wheat bran (WB), and corn steep liquor (CSL) utilizing a cell-substrate recycling system was implemented. Results: The highest outcomes were achieved using FW as the main substrate and the strategy of one cell recycling round. The best condition for amylase production (260.9 U/g) was the blend FW 50%, SCB 10%, WB 40% supplemented with a salt solution. For the highest protease level (665.5 U/g) the same mixture was supplemented by 20% CSL. Hydrolysis of FW with the enzymatic extract from the best specified blend produced 47.10 g/L of reducing sugars. Conclusion: This bioprocess showed to be cost-effective, technically not demanding, and could be scaled up successfully for commercial goals. [ABSTRACT FROM AUTHOR]

Studies on the usage of gasoline–alcohol blends as an alternative fuel in spark-ignition engines have recently gained momentum. In the present research, energy, exergy, environmental, enviroeconomic, exergoenvironmental, and exergoenviroeconomic analyses were conducted with the performance and emission values acquired by utilizing gasoline, gasoline–heptanol, and gasoline–hexanol fuels (G100, HEX5-20, and HP5-20) as a fuel under different powers at a constant speed of 1600 rpm in a single-cylinder four-stroke spark-ignition engine. As the ratio of alcohol in fuel blends increases, fuel consumption also increases. NOX emission is higher, and CO and HC emissions are lower in alcohol-based fuel blends than G100 fuel. The highest thermal efficiency is 41.09% in G100 fuel at a power of 5 kW. As the ratio of alcohol in fuel blends increases, thermal efficiency decreases. The highest exergy destruction and entropy generation were determined to be 6.25 kW and 0.02134 kW/K, respectively, in HP20 fuel at a power of 5 kW. Entropy generation increases with an increase in the ratio of alcohol in alcohol-based fuels. HEX20 and HP20 fuels produce 25% and 30% more entropy, respectively, compared to G100 fuel. The mass and financial costs of the damage caused by the CO2 emission of fuels to the environment were determined by conducting four different analyses using energy and exergy analysis data. According to the exergoenvironmental and exergoenviroeconomic analyses, HP20 fuel reached the highest environmental pollution values of 4538.19 kg CO2/month and 65.804 $/month, respectively. The environmental cost of the CO2 emission released from the exhaust to the atmosphere is higher in alcohol-based fuels than G100 fuel. As a result of all analyses, it was concluded that hexanol and heptanol could be alternative fuels in spark-ignition engines under particular conditions. [ABSTRACT FROM AUTHOR]