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Propolis is produced by honey bees from a series of resinous, gummy and balsamic substances collected from the leaf buds of different tree species and mixed with their secretions. It is used as a sealant and antiseptic in the hive. Because of its antimicrobial properties, propolis has become a popular alternative medicine or food for health protection and disease prevention. The presence of a large number of flavonoids, aromatic acids and phenolic compounds has been suggested to be responsible for most biological and pharmacological activities of propolis. This review aims to provide a critical analysis of the different studies which evaluate the activity of propolis against fungi and to identify the chemical components responsible for such activity. The discussion of the methodological approaches used and the issued results is a key point of this review to highlight knowledge gaps. This review will first describe the chemical composition of the propolis and the factors of variability including geographical and botanical origins and then examine its antifungal activities with a focus against phytopathogenic fungi. Finally, it will discuss the main components responsible for such activities and their mechanism of action.

Summary: Monoterpenes are the most prevalent compounds found in essential oils. They exhibit inhibitory actions against phytopathogenic postharvest fungi. Direct application limits their effectiveness due to their instability, high volatility, hydrophobicity and susceptibility to degradation. Encapsulation systems using metal–organic frameworks (MOFs) have been developed to maximise their use. In this study, four protocols were shown to encapsulate thymol and limonene in porous solids, such as ZIF‐8, UiO‐66‐(COOH)2 and zeolite 13X. Vapourisation and diffusion at 60 °C for 16 h was found to be the most efficient encapsulation process. A larger amount of thymol than limonene was loaded in the porous solids. Thymol released from MOFs slowed down the growth of Colletotrichum musae by up to 6 days at 25 °C. There was a sustained release of thymol even beyond the period of maximum fungal growth. This proof‐of‐concept study revealed the potential utility of MOFs as carriers of thymol against postharvest fungi. [ABSTRACT FROM AUTHOR]

High‐pressure homogenization (HPH) was applied within a range of 300 to 1000 bar for 2 to 8 cycles. At constant dry matter (6.2%), pulp mass increased from 3.7 to 8%, indicating a change in particle organization. D90 varied from 197 to 20 μm depending on the pressure and number of cycles. The aggregation of particles, then destruction of the aggregates depending on the number of cycles, explained viscosity behavior. HPH delayed phase separation by an average 28.5 h. Sedimentation velocity was 10 times higher at 8 cycles than at 3 cycles, at 1000 bar. At 1000 bar, browning was observed, resulting from Maillard reactions, and was linked to the furan‐2‐pentyl content (10‐fold higher) and a 45% loss of carotenoids. This study will help in understanding changes induced in mango nectar by HPH and will be of use in developing processing technologies to preserve mango‐based products. Novelty impact statement: This study provides some additional scientific indications for understanding the subtility of HPH impacts in stabilizing mango nectar. The optimum pressure treatment for delaying phase separation (1000 bar, 3–6 cycles), i.e., reducing particle size and forming adequate re‐aggregation, also causes a Maillard reaction (2‐fold color difference, 10‐fold furan increase, etc.), hence browning through an increase in local temperature. It will therefore be necessary to find a compromise to limit degradation reactions caused by the process, and to guarantee greater consumer acceptance (phase separation and sensory quality). [ABSTRACT FROM AUTHOR]

Oils extracted from three exotic fruits, guava, kiwi and passion fruit were analyzed to evaluate the possible commercial interest for these waste materials from fruit juices industry. Results showed interesting fatty acids compositions with high amounts of essential fatty acids such as 62.3% alpha linolenic acid for kiwi seed oil, and respectively 73.4% and 77.0% for omega 6 linoleic acid in passion fruit and guava seed oils. Fatty acids regiodistribution, sterols and tocopherols contents were also analyzed to try to establish the potential nutritional interest of such oils.

Summary: Bananas are tropical fruits that are perishable and susceptible to fungal diseases, mainly caused by Colletotrichum musae. Antimicrobial emulsion‐based coating materials have been used extensively to inhibit the growth of these fungi and extend the shelf life of bananas. Targeted emulsion‐based film functionalities offer excellent mechanical, physicochemical and barrier properties and limit fungal growth kinetics. Antifungal compounds, such as essential oils or phenolic compounds, are added to emulsion‐based (wax/biopolymer) coatings to enhance their antimicrobial properties. This study set out to formulate a beeswax‐based emulsion for banana coatings using high‐pressure homogenisation (HPH) and hydrophilic food‐grade/organic coating materials. The particle size distribution, stability and mechanical properties of the film‐forming emulsions, water vapour and the oxygen permeabilities of the resulting coating were investigated. The most promising sucrose emulsions were tested as coatings on banana fruits to assess their efficacy against moisture and firmness loss during storage. Adding thymol (0.5% w/w) to the sucrose emulsions further enhanced the inhibition of Colletotrichum musae growth to its barest minimum of <20%. Emulsion stability was clearly enhanced using HPH while the best inhibition was obtained with a 20% diluted sucrose emulsion containing 0.5% thymol, with or without HPH. [ABSTRACT FROM AUTHOR]

The objective of this study was to create a French database on the polyphenol content of fruit and vegetables as uncooked fruits and vegetables and then to evaluate polyphenol intake through fruit and vegetable consumption in France. To achieve this, we used the Folin-Ciocalteu method adapted to fruit and vegetable polyphenol quantitation (1). Vegetables with the highest polyphenol concentration were artichokes, parsley, and brussels sprouts [>250 mg of gallic acid equivalent (GAE)/100 g fresh edible portion (FEP)]; fruits with the highest concentrations were strawberries, lychees, and grapes (>180 mg of GAE/100 g FEP). Conversely, melons (Cantaloupe cv.) and avocados had the lowest polyphenol concentration for fruits and vegetables, respectively. Based on fruit consumption data, apples and strawberries are the main sources of polyphenols in the French diet, whereas potatoes, lettuces, and onions are the most important vegetable sources. Total polyphenol intake from fruit is about 3 times higher than from vegetables, due to the lower polyphenol concentration in vegetables. The calculation of polyphenol intake, based on both assessment methods used [(Societe d'Etudes de la Communication, Distribution et Publicite (SECODIP) and Supplementation en Vitamines et Mineraux Antioxydants (SUVIMAX)], showed that apples and potatoes provide approximatively half of the total polyphenol intake from fruit and vegetables in the French diet.

The influence of thermal treatment (frying of plantain) on the micronutrients ascorbic acid, potassium and carotenoids is evaluated. Cylinders (diameter 30 mm, thickness 10 mm) of plantain (Musa AAB 'barraganete') were fried at four thermal treatments (120-180[degrees]C and from 24 to 4 min) to obtain products with approximately the same water content ([approximately equal to] 0.8 [+ or -]0.02 kg/[kg.sup.1]) and fat content ([approximately equal to] 0.15 [+ or -]0.06 kg/kg). The thermal study used the cook value and the mean cook value as indicators of the effect of several different treatment temperatures and times on quality. Deep-fat frying had no significant effect on carotenoid contents at any frying conditions, and on potassium content, except at 120[degrees] C and 24 min (loss [less than or equal to] 11%). There was a significant, but not complete, loss ([less than or equal to] 45%) of ascorbic acid. The process with the greatest effect was low temperature and long time (120[degrees] C/24 min), as observed for potassium and ascorbic acid. These results are in agreement with other studies that demonstrated short thermal treatments at high temperatures protect food nutritional quality, as shown by the cook value and the mean cook value. In our work, deep-fat frying of plantain preserved most of the micronutrient contents that were evaluated. Keywords: Deep-fat frying, ascorbic acid, carotenoids, potassium, plantain

Huanglongbing (HLB) is presently a major threat to the citrus industry. Because of this disease, millions of trees are currently dying worldwide. The putative causal agent is a motile bacteria belonging to Candidatus Liberibacter spp., which is transmitted by psyllids. The bacteria is responsible for the synthesis of callose at the phloem sieve plate, leading to the obstruction of the pores that provide connections between adjacent sieve elements, thus limiting the symplastic transport of the sugars and starches synthesized in leaves to the other plant organs. The Persian triploid lime (Citrus latifolia) is one of the most HLB-tolerant citrus varieties, but the determinants associated with the tolerance are still unknown. HLB-infected diploid Mexican lime (Citrus aurantiifolia) and Persian lime were investigated. The leaf petiole was analyzed using scanning electron microscopy (SEM) to observe callose deposition at the phloem sieve plate. Leaf starch contents and detoxification enzyme activities were investigated. In the field, Persian lime leaves present more limited symptoms due to HLB than the Mexican lime leaves do. Photosynthesis, stomatal conductance, and transpiration decreased compared with control plants, but values remained greater in the Persian than in the Mexican lime. Analysis of the petiole sieve plate in control petiole samples showed that pores were approximately 1.8-fold larger in the Persian than in the Mexican lime. SEM analyses of petiole samples of symptomatic leaves showed the important deposition of callose into pores of Mexican and Persian limes, whereas biochemical analyses revealed better detoxification in Persian limes than in Mexican limes. Moreover, SEM analyses of infected petiole samples of asymptomatic leaves showed much larger callose depositions into the Mexican lime pores than in the Persian lime pores, whereas biochemical traits revealed much better behavior in Persian limes than in Mexican limes. Our results reveal that polyploids present specific behaviors associated with important physiological and biochemical determinants that may explain the better tolerance of the Persian lime against HLB compared with the Mexican lime. [ABSTRACT FROM AUTHOR]

An innovative method was developed to study the specific uncoupled effect of temperature and water activity (Aw) during mango drying. Thermal treatment of reconstituted lyophilized mango powder at targeted Aw enabled evaluation of the inactivation of polyphenol oxidase and peroxidase activity in a range 0.98–0.6 Aw and a time-temperature range of 1–4 h and 50–60°C. We established that thermal treatment of the enzymatic extract was not the same as the inactivation phenomena that occurred in the mango matrix, mainly due to differences in the pH of the buffer extract (6.4) and reconstituted food matrix (3.8). Even if the inactivation of these two enzymes was directly correlated with the temperature of the treatment, this behavior was also strongly linked to the Aw. A two-step change in the fruit was observed at high Aw (i.e., at 0.98 in fresh fruit), polyphenol oxidase (PPO) was shown to be more thermostable than peroxidase (POD), whereas when evaporation reduced the Aw to around 0.6, the opposite behavior was observed. As a consequence, enzymatic inactivation during drying should be considered as the result of the coupled effects of time-temperature and water activity. [ABSTRACT FROM AUTHOR]

Abstract: Awara (Astrocaryum vulgare M.) is a palm fruit mainly used in nutrition. We analysed the pulp oil for fatty acid, tocopherol, carotenoid, and phytosterol and we evaluated whether this oil may attenuate inflammation in vivo. In an endotoxic shock model, awara pulp oil treatment decreased pro-inflammatory cytokines and increased anti-inflammatory cytokines. In a pulmonary inflammation model, awara pulp oil treatment reduced eosinophil and lymphocyte numbers recovered into the broncho-alveolar lavages. These results suggest that awara pulp oil administration can efficiently counteract an acute and chronic inflammatory response in vivo that is probably mediated by fatty acids and minor compounds. [Copyright &y& Elsevier]

A semi-empirical model was developed to predict simultaneously time-temperature distribution inside the unripe banana and fungal reduction during the hot water dip, in order to simulate different process conditions for controlling banana anthracnose disease. For this purpose, the kinetic parameters of Colletotrichum musae reduction were estimated based on the thermal death time concept (z = 3.56 °C and D 50 ° C = 1044 s), and evaluated in different simulated media (unripe and fully ripe banana peel agar media). At the same time, a heat transfer model based on the Fourier equation was developed considering two unripe banana domains (peel and pulp). The comparison between the predicted and observed number of C. musae spores after the thermal treatment of unripe banana was satisfactory (coefficient of variation less than 10%), suggesting that the survival ratio is affected by the banana composition. The resulting model can be used to simulate different time-temperature scenarios, and to show how the parameter combinations may affect C. musae reduction in the unripe banana during the hot water dip process. • Identification of the kinetic parameters of Colletotrichum musae inactivation. • Development and validation of banana heat transfer model with two domains. • Validation of the fungal reduction in unripe banana under different scenarios. • Potential of numerical modeling for evaluating decontamination of other fruit. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Morinda citrifolia L. (Noni) is a medicinal plant used in Polynesia for many properties such as anti-inflammatory, anti-diabetic and antineoplastic effects. Recent studies showed that noni juice have anti-oxidant and acute anti-inflammatory activities likely due to polyphenols, iridoids and vitamin C content. The present study was undertaken to evaluate chronic anti-inflammatory and spasmolytic effects of noni juice. Materials and methods Therefore, we evaluated the effect of oral or intraperitoneal administrations of noni juice in vivo on the lung inflammation in ovalbumin (OVA) sensitized Brown Norway rat (with prednisolone 10 mg/kg intraperitoneously as reference compound) and the ex vivo effect of noni juice on BaCl 2 (calcium signal) or methacholine (cholinergic signal) induced spasms in jejunum segments. Results We found that noni juice (intraperitoneously 2.17 mL/kg and orally 4.55 mL/kg) reduced the inflammation in OVA-sensitized Brown Norway rat with regard to the decreased number of inflammatory cells in lung (macrophages minus 20–26%, lymphocytes minus 58–34%, eosinophils minus 53–30%, neutrophils minus 70–28% respectively). Noni juice demonstrated a dose-dependent NO scavenging effect up to 8.1 nmol of nitrites for 50 µL of noni juice. In addition noni juice inhibited (up to 90%) calcium and cholinergic induced spasms on the jejunum segments model with a rightward shift of the concentration response curve. Conclusion We describe for the first time that noni juice demonstrate (1) a chronic anti-inflammatory activity on sensitized lungs along with (2) a spasmolytic effect integrating a calcium channel blocker activity component. [ABSTRACT FROM AUTHOR]

Abstract: The physicochemical, nutritional, and functional variations of Myrtillocactus geometrizans and Myrtillocactus schenckii, were assessed. Variations of characteristics among species and geographic origin were lower compared to prickly pear. Titratable acidity, and total soluble solids varied by 7.7%, and 11%, respectively. Variations of protein (18.5%) and fibre (5.2%) contents were lower when compared to prickly pear. Iron and copper contents make Myrtillocactus a good source of minerals contributing 16% and 20% of daily requirements. Myrtillocactus also could be an outstanding source of fibre (up to 36.9%). Gallic and caffeic acids, and vanillin were identified by HPLC. Betalains, soluble phenolics, and vitamin C contribute to the high antioxidant activity (TEAC) which, if compared with commonly consumed fruits, was higher. The potential for the production of high-quality industrialised products derived from Myrtillocactus is feasible, as long as compositional variations from batch to batch are kept in check. [Copyright &y& Elsevier]

Abstract: Major compounds (i.e. phenolic compounds and carotenoids) were analysed in the extracts of the edible part of three tropical fruits: the Andean blackberry, the naranjilla and the tree tomato. Ellagitannins and anthocyanins were predominant in blackberries and phenolic composition can be used to differentiate the two species studied. Similar phenolic composition occurred in red and yellow tree tomato except for anthocyanins which were absent in the yellow tree tomato. Phenolic acids were detected in the naranjilla pulp. Carotenoids were analysed in the fruits. The composition in carotenoids was similar in the two varieties of tree tomato and their vitamin A activity was calculated. Carotenol fatty acid esters were predominant. β-Cryptoxanthin esters and β-carotene were the major carotenoids. The carotenoid content was high compared to literature data, providing an important high vitamin A activity. In blackberries and naranjilla, this class of compounds was found only at trace level. Finally, ORAC values were estimated in different solvent extracts and results were compared with published data in common fruits. [Copyright &y& Elsevier]

Abstract: Essential oil samples of Cinnamosma fragrans from two regions in Madagascar, Tsaramandroso (38 samples) and Mariarano (30 samples), were analysed by GC/MS. Fifty-seven components were identified, accounting from 88.3% to 99.4% of the oils’ composition. The major components were linalool (72.5±23.3%) in Tsaramandroso and 1,8-cineole (47.3±10.2%) in Mariarano. Samples B8 (95.8% linalool) from Tsaramandroso and B143 (71.6% 1,8-cineole) from Mariarano containing the highest proportions of the two main components identified, were selected to determine antimicrobial activities against 10 microbial strains. Bacillus subtilis and Staphylococcus aureus were the most sensitive strains to both oils. Minimum inhibitory concentration (MIC) values were lower for B143 against all tested Gram-negative strains than pure 1,8-cineole. B8 showed higher MIC values than pure linalool against Salmonella typhimurium and Vibrio alginolyticus, and similar MIC values to linalool towards the other Gram-negative strains. Both essential oils exhibited higher MIC values towards Fusarium oxysporum than their respective pure major component. These results suggested the occurrence of synergism or antagonism effects between the different oil constituents. [Copyright &y& Elsevier]

Abstract: Morinda citrifolia L., the “noni”, has been used in traditional Polynesian medicine for over 2000 years. Morinda citrifolia (Rubiaceae) is an evergreen shrub whose ripe fruit has a strong butyric acid smell and flavor. The leaves and especially the fruit are consumed in different forms by various communities (e.g., the Polynesians) throughout the world; the root is used as a dye. As a result of these uses and the market that is developing around “noni juice”, it has become increasingly important to confirm the actual therapeutic properties of this plant. While recent studies have shown that this fruit has antibiotic and antioxidant properties in vitro, we still do not have scientific evidence supporting the nutritional and medicinal values of noni in humans. However, both the fruit and damnacanthal, an anthraquinone compound extracted from noni roots, are currently being studied in the context of anti-cancer research. If, in the future, the nutritional and medical values of the noni can be assessed, especially its anti-cancer activity, this fruit could play a noticeable economic role in producing countries. [Copyright &y& Elsevier]

• 12 isoflavonoid compounds identified out of 38 detected of EERBP by HPLC-ESI/MS. • Inhibition (81%) on mycelial growth of C. musae by EERBP (1.6 g GAE L−1). • Two fractions of EERBP detected and isolated by TLC-bioautography method. • An additive effect observed through the biological activity of these 2 fractions. This study set out to highlight the in vitro and in vivo antifungal activity of an Ethanolic Extract of Red Brazilian Propolis (EERBP) and identify bioactive fractions effective against Colletotrichum musae. Active fractions were detected by the thin-layer chromatography-bioautography method and characterised by HPLC-MS n. The in vitro results showed that EERBP had strong antifungal properties against C. musae (81 ± 1% inhibition at 1.6 g GAE L−1). Medicarpin, (3 S)-vestitol and (3 S)-neovestitol were the main compounds identified in the EERBP extract (45% of all detected peaks). Two isolated fractions displayed inhibition percentages of 35 ± 4 and 42 ± 1%, respectively, on C. musae mycelial growth compared to the EERBP extract. The biological activity of the two fractions displayed an additive effect. A further in vivo investigation revealed that EERBP is a potential natural alternative for controlling banana crown rot. [ABSTRACT FROM AUTHOR]

A singular adaptive phenotype of a parthenogenetic insect species (Acyrthosiphon pisum) was selected in cold conditions and is characterized by a remarkable apparition of a greenish colour. The aphid pigments involve carotenoid genes well defined in chloroplasts and cyanobacteria and amazingly present in the aphid genome, likely by lateral transfer during evolution. The abundant carotenoid synthesis in aphids suggests strongly that a major and unknown physiological role is related to these compounds beyond their canonical anti-oxidant properties. We report here that the capture of light energy in living aphids results in the photo induced electron transfer from excited chromophores to acceptor molecules. The redox potentials of molecules involved in this process would be compatible with the reduction of the NAD+ coenzyme. This appears as an archaic photosynthetic system consisting of photo-emitted electrons that are in fine funnelled into the mitochondrial reducing power in order to synthesize ATP molecules.

High-performance liquid chromatography with diode array (LC-DAD) and electrospray ionization mass spectrometric detection (ESI-MS) was used to analyze phenolic compounds of two blackberry species ( Rubus glaucus Benth. and Rubus adenotrichus Schlech.) growing in South America. UV-visible spectrophotometry was a valuable tool for identifying the class of phenolic compound, whereas MS and MS ( n ) fragmentation data were useful for their structural characterization. Ellagitannins were the major compounds, with sanguiin H-6 and lambertianin C being the predominant ones. The anthocyanin composition as well as the presence or absence of kaempferol glycosides can be used to distinguish the Rubus species studied. Flavonol hexoside-malonates were identified in both berries. Hydroxycinnamic acids were minor compounds and found as ferulic, caffeic, and p-coumaric acid esters. Similar contents were obtained by analysis of soluble ellagitannins and ellagic acid glycosides as ellagic acid equivalents and by analysis of ellagic acid equivalents released after acid hydrolysis.

Polyphenols, widely spread in our diet by the consumption of plant food products, are commonly determined using Folin-Ciocalteu reagent that interacts with other different reducing nonphenolic substances and leads to an overestimation of polyphenol content. In this paper we report an optimized Folin-Ciocalteu method to specifically determine the contents of total polyphenols and vitamin C. After the optimal conditions for the colorimetric assay were set, solid-phase extraction (Oasis HLB (hydrophilic-lipophilic balance)) was carried out to eliminate the water-soluble reducing interferences including vitamin C. Colorimetric correction was thus performed by subtracting interfering substances contained in the water washing extract from the raw extract. Moreover, vitamin C present in the water washing extract can be destroyed by heating and thus colorimetrically deduced. This procedure was set up with synthetic solutions and validated on different extracts from fruit products.

The valorization of extracts from Brazilian vetiver (Vetiveria zizanioides (L.) Nash ex Small) roots was studied. This study took into account the extraction method, the chemical composition of the extracts, their sensorial characteristics, and the possibility of chemical transformations of the product. The performed extraction methods were hydrodistillation and extraction with supercritical carbon dioxide. Some pretreatment methods were tested on the vetiver roots and evaluated in terms of extraction yield, process time, chemical composition, and sensorial properties. Supercritical carbon dioxide extraction resulted in high yield (3.2%) in significantly less time than the other methods. The chemical compositions of the extracts obtained by the different methods were also compared to those of commercial vetiver oils from other sources, showing that Brazilian samples had a greater acid amount. An extraction in basic medium from Brazilian vetiver oil was done to remove its main acid (zizanoic acid), which was chemically transformed into an alcohol (khusimol) of desirable sensorial properties. Sensory evaluation indicated that the Brazilian volatile oil without acid could be used in perfumery and the extract obtained with supercritical carbon dioxide could have application in food., (Copyright 2004 American Chemical Society)

The physicochemical characteristics (pH, total and soluble solids, and titratable acidity), sugars, organic acids, carotenoids, anthocyanins, volatile compounds, and cell wall polysaccharides of a new pineapple hybrid (FLHORAN41 cultivar) were measured throughout maturation and compared with the Smooth Cayenne cv. At full maturity, the FLHORAN41 cv. has a higher titratable acidity and soluble solids content than the Smooth Cayenne cv. The golden yellow flesh and red-orange to scarlet shell of ripe FLHORAN41 cv. fruits are due to carotenoid and anthocyanin levels that are, respectively, 2.5 and 1.5 times higher than those of the flesh and shell of the ripe Smooth Cayenne cv., respectively. During maturation of the FLHORAN41 cv., there was an increase in all classes of aroma compounds (mainly terpene hydrocarbons and esters), although their relative proportions were similar in both cultivars at full maturity. Cell wall polysaccharides undergo little change during maturation.