Isolation and characterisation of cell wall polysaccharides from legume by-products: Okara (soymilk residue), pea pod and broad bean pod

Structural Characteristics and Multiple Bioactivities of Volvariella volvacea Polysaccharide Extracts: The Role of Extractive Solvents

The chemical structures and functional properties of plant-based polysaccharides are critically influenced by extractive solvents, but their roles are not clear. In this study, the structural characteristics and multiple bioactivities of Volvariella volvacea polysaccharides (VVPs) subjected to water (VVP-W), alkalis (sodium hydroxide, VVP-A), and acids (citric acid, VVP-C) as extractive solvents are investigated systematically. Of the above three polysaccharides, VVP-W exhibited the highest molecular weights, apparent viscosity, and viscoelastic properties. Functional analyses revealed that VVP-C had an excellent water-holding capacity, foaming properties, and emulsifying capacity, while VVP-A exhibited a promising oil-holding capacity. Moreover, VVP-C displayed strong inhibitory effects on α-amylase and α-glucosidase, which could be attributed to its content of total phenolics, proteins, and molecular weights. These findings have important implications for selecting the appropriate extraction techniques to obtain functional polysaccharides with targeted bioactive properties as food additives.

Valorization and food applications of okara (soybean residue): A concurrent review

Agriculture waste is rising continuously across the globe due to enormous industrial, food processing, and household activities. Proper valorization of this waste could be a promising source of various essential bioactive and functional ingredients. Okara is a major residue produced as result of soybean processing and has a rich nutritional profile. The nutritional profile of okara is affected by the processing conditions, variety, pre-treatment, post-production treatments, and processing techniques. Owing to the high fibers, lipids, proteins, and bioactive components, it is being used as an essential industrial ingredient in various food processing industries. The prebiotic potential and nutritional profile can be increased by various techniques, that is, enzymatic, chemical, biotransformation, high-pressure microfludization, and fermentation. The prebiotic potential of okara makes it suitable as a therapeutic agent to prevent a variety of metabolic disorders such as diabetes, obesity, hypercholesterolemia, and hyperlipidemia. The current review highlights the structural, nutritional, functional, therapeutic, and industrial applications of okara.

Upcycling soy processing waste (okara) into structured emulsions for fat replacement in sweet bread

BACKGROUND

Okara is the main waste of soy processing and represents a large economic and environmental burden. Nevertheless, the fibre and protein content of okara supports the upcycling of this critical waste. This study aimed at assessing the potentialities of okara as an innovative oil-structuring ingredient.

RESULTS

Structured emulsions containing up to 520 g oil kg^-1 and having oil holding capacity higher than 75% were prepared by high-shear mixing of okara with liquid oil. Microstructural analysis showed that the oil phase was evenly distributed in the okara matrix, probably due to the emulsification ability of the okara fibre-protein network. The performance of okara structured emulsions as palm margarine replacer were tested in the preparation of sweet bread. Okara emulsions (500 g oil kg^-1 ) resulted not only in a significant reduction of saturated fatty acids (>50%), but also in an increased protein and fibre content. Compared to the use of liquid oil solely, okara emulsions allowed reducing the oil released from bread loaf. Bread containing okara emulsion also presented physical and sensory properties similar to those of palm margarine bread, the only exception being a more perceivable oiliness and rancid defect, which are, however, easily preventable by applying appropriate formulation strategies.

CONCLUSION

The use of okara as innovative ingredient for oil structuring would answer the current demand for sustainable heathy diets, based on clean-label foods with low-saturated fat content, and increased protein and fibre supply. This approach would also allow the complete upcycling of this critical waste. © 2022 Society of Chemical Industry.

Pea (Pisum sativum L.) pod powder as a potential enhancer of probiotic Enterococcus faecium M74 in ice cream and its physicochemical, structural, and sensory effects

BACKGROUND

In this study, pea (Pisum sativum L.) pod powder (PPP) was incorporated (1% and 3% w/w) into a probiotic ice cream formulation containing Enterococcus faecium M74 to investigate the potential effect of PPP on the probiotic survivability in the ice cream throughout 60 days of frozen storage. Moreover, the produced symbiotic ice creams were evaluated for their physiochemical properties, stability, and sensory acceptability.

RESULTS

Incorporation of PPP into ice cream caused significantly (P < 0.05) increased protein and ash content and lower pH values. Besides that, the addition of PPP resulted in ice creams with higher hardness and lower overrun. A significant diminishing was observed in the melting rates of the ice creams as the percentage of PPP increased and storage time progressed. Ice cream with PPP presented lower lightness and higher greenness and yellowness compared with control. All ice creams had viable counts of E. faecium M74 of ≥6 log cfu g-1 during storage and provided the number of viable cells that the probiotic product should contain. On day 60, the viability of E. faecium M74 in ice cream containing 1% PPP (7.64 ± 0.02) was higher than the control (7.28 ± 0.00). Sensory analyses revealed that there was no statistical difference in ice cream with 1% PPP and the control without PPP in terms of general acceptability.

CONCLUSION

These results suggest that pea pods, which is a waste product of the pea industry and obtained at zero cost, could be used as a potential prebiotic and an agent to improve technological properties of dairy products. © 2022 Society of Chemical Industry.

Valorization of wastes and by-products of nuts, seeds, cereals and legumes processing

Wastes and by-products of nuts, seeds, cereals and legumes carry a unique potential for valorization into value-added ingredients due to their protein, dietary fiber, antioxidant, vitamin and mineral contents. The most crucial factor in the recovery of value-added ingredients and bioactives from the wastes and by-products is the utilization of the most efficient extraction technique. This work is an overview of the classification of wastes and by-products of nuts, seeds, cereals and legumes processing, the methods used in the extraction of valuable compounds such as proteins, dietary fibers, phenolics, flavonoids and other bioactives. This chapter provides insights on the promising applications of extracted ingredients in various end products. A special emphasis is given to the challenges and improvement methods for extraction of value-added compounds from wastes and by-products of nuts, seeds, cereals and legumes processing.

Cocoa bean shells: a review into the chemical profile, the bioactivity and the biotransformation to enhance their potential applications in foods

During processing, cocoa bean shells (CBS) are de-hulled from the bean and discarded as waste. Undermined by its chemical and bioactive composition, CBS is abundant in dietary fiber and phenolic compounds that may serve the valorization purpose of this by-product material into prebiotic and functional ingredients. In addition, the cell-wall components of CBS can be combined through enzymatic feruloylation to obtain feruloylated oligo- and polysaccharides (FOs), further enhancing the techno-functional properties. FOs have attracted scientific attention due to their prebiotic, antimicrobial, anti-inflammatory and antioxidant functions inherent to their structural features. This review covers the chemical and bioactive compositions of CBS as well as their modifications upon cocoa processing. Physical, chemical, and enzymatic approaches to extract and bio-transform bioactive components from the cell wall matrix of CBS were also discussed. Although nonspecific to CBS, studies were compiled to investigate efforts done to extract and produce feruloylated oligo- and polysaccharides from the cell wall materials.

Potential use of plant-based by-products and waste to improve the quality of gluten-free foods

The food industry generates a large amount of waste and by-products, the disposal of which has a negative impact on the environment and the economy. Plant-based waste and by-products are rich in bioactive compounds such as dietary fiber, proteins, essential fatty acids, antioxidant compounds, vitamin, and minerals, which can be exploited to reduce the nutritional deficiencies of gluten-free products. The latter are known to be rich in fats and carbohydrates but lacking in bioactive compounds; the absence of gluten also has a negative effect on textural and sensory properties. Several attempts have been made to improve the quality of gluten-free products using alternative flours and additives, or by adopting innovative technologies. The exploitation of plant-based by-products would represent a chance to improve both the nutritional profile and the overall quality of gluten-free foods by further enhancing the sustainability of the agri-food system. After examining in detail the composition of plant-based by-products and waste, the objective of this review was to provide an overview of the effects of their inclusion on the quality of gluten-free products (bread, pasta, cake/muffins, biscuits and snacks). The advantages and drawbacks regarding the physical, sensory, and nutritional properties were critically evaluated. © 2021 Society of Chemical Industry.

Sweet corn cob as a functional ingredient in bakery products

•

Incorporation of sweet corn cob flour (SCCF) in gluten free rice muffin was examined.

•

SCCF contained a higher amount of ferulic acid and dietary fiber than rice flour.

•

Muffin incorporated with 10% and 20% of SCCF showed an improvement in texture.

•

Baking increases the free ferulic acid in muffin incorporated with SCCF.

•

Muffin with SCCF showed higher mean overall liking scores in consumers liking test.

Gluten free (GF) products are often inferior in quality attributes, nutritional content and consumer acceptability. The use of GF by-products is a novel strategy to improve the structure and nutritional profile of these products. Sweet corn cob (SCC) is a by-product of sweet corn processing containing a considerable amount of fibre and ferulic acid. The effect of baking on ferulic acid content, colour, texture and physical characteristics on muffins incorporated with SCC flour (SCCF) as a value-added food ingredient was investigated using a GF model system. The freeze-dried SCCF, containing ferulic acid (6.02 mg g⁻¹) was used to replace the rice flour at varying levels of 10, 20, and 30%. In general, SCCF increased dietary fibre and free ferulic acid content of muffins. Inclusion of 20% SCCF showed an increase in terms of the height of the muffin and number of air cells in the crumb, along with a decrease in the hardness of muffins. Muffins with SCCF showed higher mean overall liking scores than rice flour muffin.

Recovery and evaluation of cellulose from agroindustrial residues of corn, grape, pomegranate, strawberry-tree fruit and fava

Considering the expected increasing demand for cellulose fibers in the near future and that its major source is wood pulp, alternative sources such as vegetable wastes from agricultural activities and agro-food industries are currently being sought to prevent deforestation. In the present study, cellulose was successfully isolated from six agroindustrial residues: corncob, corn husk, grape stalk, pomegranate peel, marc of strawberry-tree fruit and fava pod. Cellulose fibers were characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, stereomicroscopy and scanning electron microscopy (SEM). Despite the evident morphological differences among the extracted celluloses, results revealed similar compositional and thermal properties with the wood-derived commercial microcrystalline cellulose used as a control. Trace amounts of lignin or hemicellulose were detected in all cellulose samples, with the exception of corncob cellulose, that exhibited the greatest extraction yield (26%) and morphological similarities to wood-derived microcrystalline cellulose, visible through SEM. Furthermore, corncob cellulose was found to have thermal properties (TOnset of 307.17 °C, TD of 330.31 °C, and ΔH of 306.04 kJ/kg) suitable for biomedical applications.

Prebiotic Impacts of Soybean Residue (Okara) on Eubiosis/Dysbiosis Condition of the Gut and the Possible Effects on Liver and Kidney Functions

Okara is a white-yellow fibrous residue consisting of the insoluble fraction of the soybean seeds remaining after extraction of the aqueous fraction during the production of tofu and soymilk, and is generally considered a waste product. It is packed with a significant number of proteins, isoflavones, soluble and insoluble fibers, soyasaponins, and other mineral elements, which are all attributed with health merits. With the increasing production of soy beverages, huge quantities of this by-product are produced annually, which poses significant disposal problems and financial issues for producers. Extensive studies have been done on the biological activities, nutritional values, and chemical composition of okara as well as its potential utilization. Owing to its peculiar rich fiber composition and low cost of production, okara might be potentially useful in the food industry as a functional ingredient or good raw material and could be used as a dietary supplement to prevent varied ailments such as prevention of diabetes, hyperlipidemia, obesity, as well as to stimulate the growth of intestinal microbes and production of microbe-derived metabolites (xenometabolites), since gut dysbiosis (imbalanced microbiota) has been implicated in the progression of several complex diseases. This review seeks to compile scientific research on the bioactive compounds in soybean residue (okara) and discuss the possible prebiotic impact of this fiber-rich residue as a functional diet on eubiosis/dysbiosis condition of the gut, as well as the consequential influence on liver and kidney functions, to facilitate a detailed knowledge base for further exploration, implementation, and development.

Biochemical status of turkeys when fed with a complex nanoadditive

The positive effect of a complex additive based on nanozeolite and soy оkara on the biochemical status and anabolic processes in turkeys was established. Tests were carried out in the Ulyanovsk region at the facilities of a farm for young turkeys of the breed “Hybrid Grade Maker”. We formed two groups using the method of analogs: control and experimental groups of 10 birds each. The supplement was added to the diet in the amount of 100 g/head/day. The subject of the study was the blood of birds, which was taken from the axillary vein before morning feeding. Under the influence of the supplement, an increase in anabolic processes in the body of turkeys was revealed. An increase in albumin by 7.38% p<0.05, creatinine by 19.32% p<0.05 with a decrease in nitrogenous products was found. It is confirmed by an increase in the average daily weight gains of turkeys by 13-18.3%. There was a decrease in the activity of AST aminotransferases. Decreased of the products nitrous metabolism is revealed: urea concentration per uric acid. Improved feather cover of birds and reduced cannibalism among birds.

Chemical Modification of Biomass Okara Using Poly(acrylic acid) through Free Radical Graft Polymerization

Okara (Ok) or soybean residue is produced as a byproduct from the soybean milk and soybean curd industries world wide, most of which is disposed or burned as waste. It is important to explore the possibilities to convert okara to useful materials, because okara is a naturally renewable bioresource. Here, we report the chemical modification of okara by grafting poly(acrylic acid) (PAA) onto the backbones of okara in water medium and the characterization of the Ok-PAA graft copolymers. It was found that the received okara mainly contained insoluble contents in water. The insoluble okara component Ok(Ins) was suspended in water and activated with ammonium persulfate as an initiator, followed by grafting PAA through a free radical polymerization. After the graft polymerization, the product (Ok-PAA) was separated into precipitate and supernatant, which were dried to give Ok-PAA(pre) and Ok-PAA(sup), respectively. It was found that PAA was grafted on Ok backbones and co-precipitated with the insoluble Ok. In addition, Ok-PAA(sup) was found to be translucent as a result of the grafting of PAA. Further, the successful grafting of PAA onto okara backbones was proven by Fourier transform infrared, thermogravimetric analysis, and microscopic measurements. Ok-PAA(sup) dispersed in water formed nanoparticles with an average diameter of 420 nm, while Ok-PAA(pre) was clustered coarse particles in water. The rheological data including the storage modulus, loss modulus, and viscosity indicated that the Ok-PAA product was a viscoelastic gel-like material with potential for agricultural and environmental applications.

Valorisation of By-Products from Soybean (Glycine max (L.) Merr.) Processing

In recent years, increased awareness of the health benefits associated with consuming soy-based foods, knowledge of milk-related allergies and a move towards more sustainable food production have led to an increase in the number of available soy-based products. The biggest producers in the world, the USA, South America and China, are from the Pacific region. This enormous production is accompanied by the accumulation of related by-products, in particular, a substance that is known as okara. Okara is a paste that is rich in fibre (50%), protein (25%), fat (10%), vitamins and trace elements. Its proper use would lead to economic advantages and a reduction in the potential for polluting the environment. Its high fibre content and low production costs mean that it could also be used as a dietary supplement to prevent diabetes, obesity and hyperlipidaemia. Chemical or enzymatic treatment, fermentation, extrusion, high pressure and micronisation can all increase the soluble fibre content, and thus improve nutritional quality and processing properties. However, the product also degrades rapidly due to its high moisture content (70-80%), which makes it difficult to handle and expensive to dry by conventional means. The aim of this paper is therefore to thoroughly study the existing literature on this subject in order to develop a general protocol for okara exploitation and valorisation. A cost/benefit analysis could drive the design of eco-friendly, sustainable protocols for the preparation of high-value nutritional products.

State-of-the-Art Production Chains for Peas, Beans and Chickpeas-Valorization of Agro-Industrial Residues and Applications of Derived Extracts

The world is confronted with the depletion of natural resources due to their unsustainable use and the increasing size of populations. In this context, the efficient use of by-products, residues and wastes generated from agro-industrial and food processing opens the perspective for a wide range of benefits. In particular, legume residues are produced yearly in very large amounts and may represent an interesting source of plant proteins that contribute to satisfying the steadily increasing global protein demand. Innovative biorefinery extraction cascades may also enable the recovery of further bioactive molecules and fibers from these insufficiently tapped biomass streams. This review article gives a summary of the potential for the valorization of legume residual streams resulting from agro-industrial processing and more particularly for pea, green bean and chickpea by-products/wastes. Valuable information on the annual production volumes, geographical origin and state-of-the-art technologies for the extraction of proteins, fibers and other bioactive molecules from this source of biomass, is exhaustively listed and discussed. Finally, promising applications, already using the recovered fractions from pea, bean and chickpea residues for the formulation of feed, food, cosmetic and packaging products, are listed and discussed.

Preparation, characterization, antioxidant and antiglycation activities of selenized polysaccharides from blackcurrant

An ultrasound-assisted enzymatic method was used to extract the polysaccharides from blackcurrant fruits (BP), and then a nitric acid-sodium selenite method was employed to prepare twelve kinds of selenized blackcurrant polysaccharides (SBPs). Among them, SBP-1, SBP-2 and SBP-3 with different selenium contents of 250 ± 11, 312 ± 15 and 643 ± 24 μg g⁻¹, displayed relatively higher 2,2-diphenyl-1-picrylhydrazyl radical (DPPH˙) scavenging activities than the others. After treating with a Sepharose-6B chromatography column, the purified blackcurrant polysaccharide (PBP) and three selenized polysaccharides (PSBP-1, PSBP-2, PSBP-3) with high purity were obtained. Compared with PBP, PSBPs possessed a larger absolute value of zeta potential (ZP) and smaller particle size, indicating the positive influence of selenized modification on physical stability of polysaccharides. Ultraviolet (UV), Fourier transform infrared (FT-IR) and circular dichroism (CD) spectra confirmed that selenium had been introduced onto the polysaccharide structure. X-ray diffraction (XRD) and I₂–KI reaction results indicated that selenized modification did not cause an obvious change in crystal form and branch structure of blackcurrant polysaccharides. In addition, PSBPs were superior to PBP in antioxidant and antiglycation capacities, and the bioactivities of PSBPs were significantly improved in positive correlation with selenium content. This study suggested that PSBPs may be a potential selenium source and serve as functional food and medicine.

An ultrasound-assisted enzymatic method was used to extract the polysaccharides from blackcurrant fruits (BP), and then a nitric acid-sodium selenite method was employed to prepare twelve kinds of selenized blackcurrant polysaccharides (SBPs).

Eco-friendly and biodegradable cellulose hydrogels produced from low cost okara: towards non-toxic flexible electronics

With increasing resource shortage and environmental pollution, it is preferable to utilize materials which are sustainable and biodegradable. Side-streams products generated from the food processing industry is one potential avenue that can be used in a wide range of applications. In this study, the food by-product okara was effectively reused for the extraction of cellulose. Then, the okara cellulose was further employed to fabricate cellulose hydrogels with favorable mechanical properties, biodegrablability, and non-cytotoxicity. The results showed that it could be biodegraded in soil within 28 days, and showed no cytotoxicity on NIH3T3 cells. As a proof of concept, a demostration of wearable and biocompatible strain sensor was achieved, which allowed a good and stable detection of human body movement behaviors. The okara-based hydrogels could provide an alternative platform for further physical and/or chemical modification towards tissue engineering, medical supplies, or smart biomimetic soft materials.

Effect of sequential twin screw extrusion and fungal pretreatment to release soluble nutrients from soybean residue for carotenoid production

BACKGROUND

Soybean residue (okara) is an agricultural by-product, which is rich in protein and fiber. This study evaluated a novel sequential process which combined fungal pretreatment (F) and twin screw extruder (E), to hydrolyze okara. The sequence of the pretreatment steps, and extruder at screw speeds 200 rpm (200) or 600 rpm (600), were tested. Next, soluble nutrients were extracted to create Fokara, EFokara200, EFokara600, FEokara200 and FEokara600 okara media.

RESULTS

All the prepared okara media could support the growth and carotenoid production by the yeast Rhodosporidium toruloides. This suggested that okara proteins and polysaccharides were successfully hydrolyzed by extrusion and fungal pretreatment, into soluble nutrients. Rhodosporidium toruloides accumulated the highest biomass of 23.7 mg mL-1 dry cell weight (DCW), when grown on FEokara600 media. This was higher as compared to commercial YPG (yeast extract-peptone-glycerol) media (18.7 mg mL-1 DCW). However, R. toruloides accumulated the highest carotenoid production of 13.2 µg mL-1 when grown on EFokara200 media as the nutrient source. This was comparable to carotenoid production of 13.1 µg mL-1 when R. toruloides was grown on YPG media.

CONCLUSION

Extrusion in combination with fungal pretreatment, is a low cost process, to hydrolyze and re-use okara, for carotenoid production. © 2018 Society of Chemical Industry.

Identification of polysaccharides extracted from pea pod by-products and evaluation of their biological and functional properties

A three-variable Box-Behnken design was employed to obtain the best possible combination of extraction time, ratio (raw material/water) and extraction temperature to allow maximum extraction yield of polysaccharides from pea pod (PPP). The preferred extraction conditions were: extraction time 195 min, extraction temperature 70 °C and ratio of raw material/water 1/40. Under these conditions, the experimental yield was 16.21 ± 1.12%, which is in close agreement with the value predicted by response surface methodology model yield (16.08 ± 0.95%). The molecular weight distribution of PPP showed two peaks with MW of 5217 kDa and 50 kDa, respectively. The main monosaccharides in PPP were galactose, xylose and arabinose, whereas the major functional groups identified from FT-IR spectrum included CO, OH and CH. In addition, PPP had high 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and a moderate reducing power. The antibacterial activity of PPP was also observed against the tested microorganisms and at 50 mg/mL PPP could inhibit the growth of the Gram-negative and Gram-positive bacteria. Generally, these results suggest that the PPP has significant antioxidant activity and good antibacterial activity and can potentially be used as additive in food, pharmaceutical and cosmetic preparations.

Profiling of phenolic compounds and antioxidant properties of European varieties and cultivars of Vicia faba L. pods

Vicia faba L. pods are a by-product generated from the industrial processing of beans for human and animal consumption. As phenolic compounds may play important roles in health, the present work envisaged the phenolic characterization of seven European varieties and cultivars of V. faba (major and minor) pods and the assessment of their antioxidant activity. The V. faba methanolic extracts were characterized by HPLC-DAD-MS/MS for identification of polyphenolic compounds. The total phenolic content and antioxidant capacity of the extracts were evaluated by colorimetric methods (Folin-Ciocalteu, DPPH scavenging capacity assay, and FRAP assay). Main compounds identified by HPLC-DAD-MS/MS were derivatives of caffeic acid, coumaric acid and kaempferol. The broad bean Jögeva variety presented the highest content of free and esterified phenolics (26.3 and 26.7 mg 100 g^-1 dry weight, respectively), followed by the horse bean varieties Bauska and Lielplatones. These results were corroborated by the analysis of total phenolic content, DPPH scavenging capacity and FRAP. This study confirmed the rich phenolic content of V. faba pods suggesting to be an interesting novel source for animal nutrition, promoting product quality and consumers' health.

Soil environment is a key driver of adaptation in Medicago truncatula: new insights from landscape genomics

Spatial differences in environmental selective pressures interact with the genomes of organisms, ultimately leading to local adaptation. Landscape genomics is an emergent research area that uncovers genome-environment associations, thus allowing researchers to identify candidate loci for adaptation to specific environmental variables. In the present study, we used latent factor mixed models (LFMMs) and Moran spectral outlier detection/randomization (MSOD-MSR) to identify candidate loci for adaptation to 10 environmental variables (climatic, soil and atmospheric) among 43 515 single nucleotide polymorphisms (SNPs) from 202 accessions of the model legume Medicago truncatula. Soil variables were associated with a large number of candidate loci identified through both LFMMs and MSOD-MSR. Genes tagged by candidate loci associated with drought and salinity are involved in the response to biotic and abiotic stresses, while those tagged by candidates associated with soil nitrogen and atmospheric nitrogen, participate in the legume-rhizobia symbiosis. Candidate SNPs identified through both LFMMs and MSOD-MSR explained up to 56% of variance in flowering traits. Our findings highlight the importance of soil in driving adaptation in the system and elucidate the basis of evolutionary potential of M. truncatula to respond to global climate change and anthropogenic disruption of the nitrogen cycle.

Preparation and characterization of nanoparticles from quaternized cyclodextrin-grafted chitosan associated with hyaluronic acid for cosmetics

Hyaluronic acid (HA, 20–50 kDa) is a hydrophilic macromolecule  with anti-wrinkle effects and moisturizing properties. However, its high molecular weight prevents it from penetrating into the deeper layers of the skin and, thus, limits its benefits to topical effects. Thus, the objective of this study is to prepare nanoparticles of quaternized cyclodextrin-grafted chitosan (QCD-g-CS) associated with HA in different molar ratios of QCD-g-CS and HA. The conjugation of the carboxylic moieties of HA and the amides of QCD-g-CS was confirmed by Fourier-transform infrared spectroscopy. Thus, the system was optimized to create nanoparticles with a small size (235.63 ± 21.89 nm), narrow polydispersity index (0.13 ± 0.02), and zeta potential of 16.07 ± 0.65 mV. The association efficiency and loading efficiency were determined by ultra-performance liquid chromatography as 86.77 ± 0.69% and 10.85 ± 0.09%, respectively. The spherical morphology of the obtained nanoparticles was confirmed by transmission electron microscopy. Moreover, the in-vitro hydrating ability was significantly higher (P < 0.001) than that of bulk HA (3.29 ± 0.41 and 1.71 ± 0.05 g water/g sample, respectively). The safety of these nanoparticles at concentrations in the range of 0.01–0.10 mg/ml was confirmed via tests on human skin fibroblasts. Together, these results demonstrate that the developed nanoparticles are promising for future applications in cosmetics.

Physicochemical properties of water-soluble polysaccharides from black cumin seeds

In the present work, water-soluble polysaccharides were isolated from black cumin seeds. Polysaccharides were characterized by their carbohydrate composition, molecular weight, thermal stability and by FTIR, NMR spectroscopy and X-ray diffraction. The surface, the functional and the antioxidant properties of black cumin water-soluble polysaccharides (BCWSP) were also investigated. BCWSP consisted mainly of galacturonic acid (30.20%), glucuronic acid (17.66%) and neutral sugar (22.99%). BCWSP was composed of high peak molecular weight. The FTIR spectrum obtained for BCWSP showed two most important absorptions, at 1659 and 1085 cm^-1, which corresponded to COO^- of uronic acids and pyranose form, respectively. NMR spectroscopy data suggested that the BCWSP is probably a rhamnogalacturonan backbone with galactan and arabinan side chains. X-ray pattern revealed the semi-crystalline behavior of BCWSP. WHC and OHC of BCWSP were relatively high and varied with temperatures. The polysaccharide zeta potential was greatly affected by pH. Results indicated that the decrease of surface tension has influenced foaming and emulsifying capacities. The DPPH radical scavenging activity of the BCWSP was 63.25% at 1 mg/mL. The BCWSP displayed moderate reductive, β carotene bleaching and chelating abilities. Overall, our results suggested that BCWSP could be used as alternative additives in food and non-food products.

Enzyme-based processing of soybean carbohydrate: Recent developments and future prospects

Soybean is well known for its high-value oil and protein. Carbohydrate is, however, an underutilized major component, representing almost 26-30% (w/w) of the dried bean. The complex soybean carbohydrate is not easily hydrolyzable and can cause indigestibility when included in food and feed. Enzymes can be used to hydrolyze the carbohydrate for improving soybean processing and value of soybean products. Here the enzyme-based processing developed for the following purposes is reviewed: hydrolysis of different carbohydrate-rich by/products from soybean processing, improvement of soybean oil extraction, and increase of nutritional value of soybean-based food and animal feed. Once hydrolyzed into fermentable sugars, soybean carbohydrate can find more value-added applications and further improve the overall economics of soybean processing.

Biotransformation with cellulase, hemicellulase and Yarrowia lipolytica boosts health benefits of okara

Okara (soybean residue) is a highly perishable food processing by-product from soymilk and tofu manufacture. It contains a large proportion of insoluble dietary fibre (40-60% on a dry basis), as well as digestion-resistant proteins, trypsin inhibitors and phytic acid. These factors contribute lead to the under-utilisation of okara. To improve the overall nutritional quality of okara, sequential saccharification of okara by Celluclast® 1.5L (cellulase) or Viscozyme® L (cellulase and hemicellulase) and fermentation by the yeast Yarrowia lipolytica were performed. The changes in the antioxidant capacity, amino acids, phenolic acids, isoflavones, phytic acid and dietary fibre during biotransformation were studied. Carbohydrase pre-treatment increased the amounts of monosaccharides, trans-cinnamic acid and aglycone isoflavones in okara. After fermentation, the okara had higher antioxidant activity and greater amounts of total amino acids and ferulic acid. Some positive interactions between the carbohydrase and Y. lipolytica were hypothesised: the carbohydrase and Y. lipolytica proteases could have synergised with each other to break down the okara secondary cell wall more efficiently. After 52 h, Celluclast® 1.5 L and Viscozyme® L significantly reduced the insoluble dietary fibre content from 61.9 ± 0.6 to 45.6 ± 3.0% and 24.7 ± 0.3%, respectively (all w/w, dry basis), while increasing the soluble dietary fibre content by about onefold. Both carbohydrases also increased the amounts of monosaccharides, trans-cinnamic acid, and aglycone isoflavones in okara. The addition of Y. lipolytica led to a higher antioxidant capacity and greater amounts of total amino acids and ferulic acid in okara. The overall improvements in the digestibility and potential health benefits of okara highlight the promising applicability of biotransformation in okara valorisation.

Preparation and efficacy assessment of malva nut polysaccharide for skin hydrating products

INTRODUCTION

Scaphium scaphigerum or malva nut has long been served in Chinese medicine. However, the use of this herb in modern health care applications has, to date, been rarely reported.

MATERIALS AND METHODS

Maceration of the herb in water afforded malva nut polysaccharide which was standardized. Safety and skin hydrating efficacy of the polysaccharide and products were evaluated in human volunteers.

RESULTS

Malva nut polysaccharide (41.71±0.64%) having 36.58±0.51% total sugar content was isolated, with further analysis quantifying ash, carbohydrate, reducing sugar and moisture contents to be 6.05±0.00, 40.06±1.00, 12.20±0.05 and 12.64±0.31%, respectively. The polysaccharide exhibited swelling and hydrating capacities of 0.46±0.01% and 54.46±0.02g/g, with L*, a* and b* of 52.56±0.04, 9.02±0.06 and 18.42±0.03, respectively, and a viscosity of 1263.00±2.00 cps. Accelerated testing indicated the biopolysaccharide to be stable, resulting in no skin irritation in 15 human volunteers. The skin hydrating efficacy as assessed via a randomized single-blind, placebo-controlled study in 24 volunteers highlighted the superior performance of malva nut over the vehicle (moisture retainment for 70min as examined by Corneometer^® CM 825). A stable skin moisturizing gel containing malva nut was developed and was shown to exhibit improved performance over benchmark tamarind and algae polysaccharide gels (after 180min observation).

CONCLUSION

Malva nut polysaccharide has potential as a key ingredient in skin hydrating products, which should encourage its further development.

Flavonoid-rich agro-industrial residues for enhanced bacterial laccase production by submerged and solid-state fermentation

Laccases have potential applications in industrial, biotechnological, and environmental set ups. Development of cost effective and efficient production technologies has gained significant attention in recent years. To enhance the laccase production from Rheinheimera sp. (Gram negative) using submerged fermentation (SmF) and from Lysinibacillus sp. (Gram positive) using solid-state fermentation (SSF), the inducing effect of various flavonoid-rich agro-industrial residues was investigated. Peels of citrus fruits, soybean meal, tofu dreg, lignin monomers, and lingo-cellulosic waste, used tea leaves and peels of onion and kiwi, paper, and dying industry effluents were tested as inducers. In SmF, 0.1% of soybean meal, tofu dreg, and powdered orange peel were best, enhancing the laccase production 2.57-, 2.11-, and 2.05-fold, respectively. In SSF, 10 mg (w/w) of used tata acti green tea leaves per 5 g of wheat bran, 1% pulp and paper industry effluent (agro based), and 1% wine made from Sygium cumini enhanced the laccase production 2.69-, 2.61-, and 2.09-fold, respectively. These results suggest the utilization of these flavonoid and phenolic-rich waste materials to be potential enhancers of industrially important laccase production.

Oxidative cleavage and hydrolytic boosting of cellulose in soybean spent flakes by Trichoderma reesei Cel61A lytic polysaccharide monooxygenase

The auxiliary activity family 9 (AA9) copper-dependent lytic polysaccharide monooxygenase (LPMO) from Trichoderma reesei (EG4; TrCel61A) was investigated for its ability to oxidize the complex polysaccharides from soybean. The substrate specificity of the enzyme was assessed against a variety of substrates, including both soy spent flake, a by-product of the soy food industry, and soy spent flake pretreated with sodium hydroxide. Products from enzymatic treatments were analyzed using mass spectrometry and high performance anion exchange chromatography. We demonstrate that TrCel61A is capable of oxidizing cellulose from both pretreated soy spent flake and phosphoric acid swollen cellulose, oxidizing at both the C1 and C4 positions. In addition, we show that the oxidative activity of TrCel61A displays a synergistic effect capable of boosting endoglucanase activity, and thereby substrate depolymerization of soy cellulose, by 27%.

Optimization of Ultrasound-Assisted Extraction, Preliminary Characterization and In Vitro Antioxidant Activity of Polysaccharides from Green Pea Pods

In this study, ultrasound-assisted extraction of green pea pod polysaccharide (GPPP) was investigated and optimized using a central composite response surface design coupled with a numerical optimization technique. The effects of ultrasonic power (50-150 W), sonication time (20-80 min), ratio of water to raw material (20:1-40:1 mL/g) and extraction temperature (40-80 °C) on polysaccharide extraction yield were studied. The maximum extraction yield was obtained with a sonication power of 135.34 W, extraction time of 48.61 min, ratio of water to raw material of 33.6:1 mL/g and extraction temperature of 68.25 °C. Under these conditions, the experimental yield was 7.37% ± 0.13%, which was in close agreement with the predicted value (7.20%). The GPPP has been analyzed in order to identify a variety of chemical properties. The FT-IR spectrum demonstrated obvious characteristic peaks of polysaccharides. Furthermore, antioxidant activity of GPPP was evaluated by various antioxidant assays in vitro. The results revealed that GPPP possessed considerable DPPH free radical scavenging activity (91.03%), reducing power (0.63) and ferric reducing antioxidant power (0.34 mmol/L) at a total amount of 0.9 mg/mL. These findings indicated that GPPP extracted using an ultrasound-assisted extraction technique has potential as a novel source of natural antioxidant agent for future applications.

Okara (soybean residue) biotransformation by yeast Yarrowia lipolytica

Okara, or soybean residue, is a soy food processing by-product from the manufacture of soymilk and soybean curd (tofu). In this study, solid-state fermentation of okara was conducted over 5days using yeast Yarrowia lipolytica, and the changes in proximate composition, antioxidant capacity, non-volatiles and volatiles were investigated. Yeast metabolism of okara significantly increased the amounts of lipid, succinate and free amino acids and enhanced the antioxidant capacity. In particular, there was a marked increase in important umami tastants after fermentation, with 3-fold increase in succinate and a 20-fold increase in glutamate. The final fermented okara contained 3.37g succinate and 335mg glutamate/100g dry matter. Aldehydes and their derived acids in the fresh okara were catabolised by Y. lipolytica mainly to methyl ketones, leading to a reduced grassy off-odour and a slightly pungent, musty and cheese-like odour in the fermented okara. Amino acid-derived volatiles, such as 3-methylbutanal and 2-phenylethanol, were also produced. Overall, the okara fermented by Y. lipolytica had a greater amount of umami-tasting substances, a cheese-like odour, improved digestibility and enhanced antioxidant capacity. These changes highlight the potential of Yarrowia-fermented okara as a more nutritious, savoury food product or ingredient. Y. lipolytica was thus demonstrated to be suitable for the biovalorisation of this soy food processing by-product.

Pea and Broad Bean Pods as a Natural Source of Dietary Fiber: The Impact on Texture and Sensory Properties of Cake

Attention has focused on bakery products such as cake which is one of the most common bakery products consumed by people in the world. Legume by-products, pea pods (PPs) (Pisum sativum L.) and broad bean pods (BBPs) (Vicia faba L.) mediterranean (Tunisian), has been studied for its high dietary fiber content (PP: 43.87 g/100 g; BBP: 53.01 g/100 g). Protein content was also a considerable component for both by-products. We investigated the effect of substituted of 5%, 10%, 15%, 20%, 25%, and 30% of PP and BBP flours on the sensory and technological properties in cake. Cakes hardness increased whereas L* and a* color values decreased. The overall acceptability rate showed that a maximum of 15% of PP and BBP flours can be added to prepare acceptable quality cakes.