Phenolics, phytic acid, and phytase in Canadian-grown low-tannin faba bean (Vicia faba L.) genotypes

Nutrient Levels, Bioactive Metabolite Contents, and Antioxidant Capacities of Faba Beans as Affected by Dehulling

Legume dehulling often removes anti-nutrients while improving nutritional quality. However, the process may reduce the levels of other health-promoting metabolites. This study investigated the effect of dehulling on major nutrients, bioactive metabolites, and antioxidant activities using 22 faba bean cultivars typically grown in different parts of the world. The faba bean cultivars differed significantly in all the parameters assessed. Crude fiber (CFC), dietary fiber (DFC), crude protein, and crude fat contents were in the ranges of 5.24-10.56, 16.17-25.15, 19.83-30.90, and 0.79-1.94% in the whole seeds and 0.96-1.59, 4.14-9.50, 22.47-36.61, and 1.13-2.07% in the dehulled seeds, respectively. Moreover, fatty acids including palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid, bioactive metabolites including total phenol (TPC), total saponin (TSC), and total tannin (TTC) contents, and antioxidant activities including ABTS•+-scavenging activity, ferric antioxidant power (FRAP), and DPPH•-scavenging activity also showed significant variations. Dehulling significantly reduced DFC (55.09-79.30%), CFC (69.61-87.52%), and TTC (1.70-66.99%) in all the faba bean cultivars while increasing total protein content (9.31-17.69%). Dehulling also increased the total fat content (3.02-48.13%) in all the cultivars except Giant Three Seeded, a Japanese cultivar, which showed a 12.62% decrease. In contrast, dehulling exhibited varying results on fatty acids, TPC, TSC, and antioxidant activities among the faba bean cultivars. Accordingly, three cultivars: Primus from Hungary, Levens Marschbohne from Germany, and Ascott from France, exhibited simultaneous increases in nutritional levels after dehulling. Domasna-2 from Macedonia, Abawi# 1 from Peru, Seville from the United Kingdom, and Large Mazandran from Iran, on the other hand, exhibited marked reductions in nutritional levels, functional metabolites, and antioxidant activities. In general, our findings indicated that dehulling reduces crude fiber, dietary fiber, and tannin levels while increasing protein and fat contents in faba beans. However, fatty acids, phenolic content, and antioxidant activity may not be equally affected by dehulling and, therefore, specific genotypes should be inspected.

The challenge of breeding for reduced off-flavor in faba bean ingredients

The growing interest in plant protein sources, such as pulses, is driven by the necessity for sustainable food production and climate change mitigation strategies. Faba bean (Vicia faba L.) is a promising protein crop for temperate climates, owing to its remarkable yield potential (up to 8 tonnes ha-1 in favourable growing conditions) and high protein content (~29% dry matter basis). Nevertheless, the adoption of faba bean protein in plant-based products that aim to resemble animal-derived counterparts is hindered by its distinctive taste and aroma, regarded as "off-flavors". In this review, we propose to introduce off-flavor as a trait in breeding programs by identifying molecules involved in sensory perception and defining key breeding targets. We discuss the role of lipid oxidation in producing volatile and non-volatile compounds responsible for the beany aroma and bitter taste, respectively. We further investigate the contribution of saponin, tannin, and other polyphenols to bitterness and astringency. To develop faba bean varieties with diminished off-flavors, we suggest targeting genes to reduce lipid oxidation, such as lipoxygenases (lox) and fatty acid desaturases (fad), and genes involved in phenylpropanoid and saponin biosynthesis, such as zero-tannin (zt), chalcone isomerase (chi), chalcone synthase (chs), β-amyrin (bas1). Additionally, we address potential challenges, including the need for high-throughput phenotyping and possible limitations that could arise during the genetic improvement process. The breeding approach can facilitate the use of faba bean protein in plant-based food such as meat and dairy analogues more extensively, fostering a transition toward more sustainable and climate-resilient diets.

Refining the metabolisable energy value of field beans for turkeys

1. This study examined the feeding value of ten UK grown field bean (Vicia faba L. var. minor) cultivar samples from the same harvest year on nitrogen corrected apparent metabolisable energy (AMEn) and nutrient retention coefficients when fed to young female turkeys.2. A balancer feed (BF) was formulated to contain 12.39 MJ/kg ME and 269 g/kg crude protein. Ten nutritionally complete, mash diets were prepared by mixing 200 g/kg of each ground field bean cultivar with 800 g/kg of the BF, totalling eleven diets. Diets were fed to female BUT Premium turkeys from 40 to 50 d of age. Each diet was fed to eight raised floor pens, housing two birds, following randomisation. The AMEn was determined by the total collection technique over the last 4 d of the study. Relationships were examined between AMEn, chemical composition and quality variables of the field bean samples.3. The overall determined AMEn value of the beans ranged from 7.72 MJ/kg DM to 9.87 MJ/kg DM, giving an average AMEn of 8.80 MJ/kg DM (P < 0.05). The soluble non-starch polysaccharide (NSP) content of the beans negatively correlated with their determined AMEn (r = -0.730; P < 0.05). Bean flour lightness-darkness degree (L*) correlated positively with the AMEn (r = -0.643; P < 0.05)4. A positive correlation was observed between the degree of yellowness-blueness of bean flour and condensed tannins content (r = 0.696; P < 0.05). Step-wise regression indicated that soluble NSP + L* of field beans provided explanatory variables suitable for estimating the AMEn value for turkeys (r2 = 0.737; P < 0.05).

Antioxidant and Anti-Inflammatory Capacities of Fractions and Constituents from Vicia tetrasperma

The young leaves and shoots of V. tetrasperma are consumed daily as cooked vegetables and can provide various health benefits. The antioxidant and anti-inflammatory capacities of its total extract and fractions were accessed for the first time in this study. The bioactivities guided the separation of the active fraction (EtOAc), leading to the identification of nine flavonoid glycoside compositions from this plant for the first time. In addition, the fractions and all isolates were evaluated for their inhibition against NO and IL-8 production in LPS-stimulated RAW264.7 and HT-29 cell lines, respectively. The most active ingredient was further assayed for its inhibitory abilities to iNOS and COX-2 proteins. Indeed, its mechanisms of action modes were confirmed by Western blotting assays through the reduction in their expression levels. An in silico approach revealed the substantial binding energies of docked compounds into established complexes to verify their anti-inflammatory properties. In addition, the presence of active components in the plant was validated by an established method on the UPLC-DAD system. Our research has boosted the value of this vegetable's daily use and provided a therapeutic approach for the development of functional food products for health improvement regarding the treatment of oxidation and inflammation.

Antioxidant and Chemopreventive Activity of Protein Hydrolysates from Raw and Germinated Flour of Legumes with Commercial Interest in Colorectal Cancer

Legumes are a highly nutritious source of plant protein, fiber, minerals and vitamins. However, they also contain several bioactive compounds with significant potential benefits for human health. The objectives of this study were to evaluate the antioxidant, antitumor and chemopreventive activity of functional extracts from legumes using raw and germinated flours of six legume species of commercial interest. The methodology carried out consisted on the development of protein hydrolysates, assessment of their antioxidant capacity and in vitro tests on T84, HCT15 and SW480 colorectal cancer (CRC) cell lines. Our results showed a high antitumor activity of protein hydrolysate from M. sativa. Likewise, when combined with 5-Fluorouracile (5-Fu), there was a synergistic effect using extract concentrations from 50 to 175 µg/mL and 5-Fu concentrations from 1.5 to 5 µM. Similarly, the induction effect on detoxifying enzymes by the extracts of M. sativa, germinated V. faba Baraca × LVzt1 and V. narbonensis, which produced a higher induction rate than the positive control sulforaphane (10 µM), should be highlighted. Therefore, incorporating these enzymes into the diet could provide nutritional effects, as well as play an effective role in cancer chemoprevention and therapy.

The modification of volatile and nonvolatile compounds in lupines and faba beans by substrate modulation and lactic acid fermentation to facilitate their use for legume-based beverages-A review

Lupines and faba beans are promising ingredients for the beverage industry. They contain high amounts of protein and can be grown in different climate zones and agricultural areas. Therefore, these legumes appear as ideal raw material for vegan, functional, and sustainable beverages. Nevertheless, the sensory characteristic of legumes is generally not accepted in beverages. Therefore, the market contribution of legume-based beverages is currently only marginal. This review highlights known major flavor aspects of lupines and faba beans and the possibilities to improve these by germination, heat treatment, enzymatic treatment, and subsequent lactic acid fermentation. First, the main aroma and taste compounds are described. Thereby, the "beany" aroma is identified as the most relevant off-flavor. Second, the nutrients and antinutrients of these legumes regarding to their use as food and as substrate for lactic acid fermentation are reviewed, and possibilities to modulate the substrate are summarized. Finally, the modification of the sensory profile by lactic acid fermentation is outlined. To conclude, it seems likely that the nutritional and flavor attributes in legume-based beverages can be improved by a combined process of substrate modulation and fermentation. In a first step, antinutrients should be decomposed and proteins solubilized while transforming the solid grains into a liquid substrate. Due to such substrate modulation, a broader variety of strains could be employed and the fermentation could be based exclusively on their impact on the flavor. By applying the concept of combining a substrate modulation with a subsequent fermentation, the use of legumes in beverages could be facilitated and new products like vegan, protein-rich, refreshing beverages could be marketed.

Effect of Lactic Acid Fermentation on Legume Protein Properties, a Review

Legume proteins have a promising future in the food industry due to their nutritional, environmental, and economic benefits. However, their application is still limited due to the presence of antinutritional and allergenic compounds, their poor technological properties, and their unpleasant sensory characteristics. Fermentation has been traditionally applied to counteract these inconveniences. At present, lactic acid fermentation of legumes is attracting the attention of researchers and industry in relation to the development of healthier, tasty, and technologically adapted products. Hence, we aimed to review the literature to shed light on the effect of lactic acid fermentation on legume protein composition and on their nutritional, functional, technological, and sensorial properties. The antimicrobial activity of lactic acid bacteria during legume fermentation was also considered. The heterogenicity of raw material composition (flour, concentrate, and isolate), the diversity of lactic acid bacteria (nutriment requirements, metabolic pathways, and enzyme production), and the numerous possible fermenting conditions (temperature, time, oxygen, and additional nutrients) offer an impressive range of possibilities with regard to fermented legume products. Systematic studies are required in order to determine the specific roles of the different factors. The optimal selection of these criteria will allow one to obtain high-quality fermented legume products. Fermentation is an attractive technology for the development of legume-based products that are able to satisfy consumers’ expectations from a nutritional, functional, technological, and sensory point of view.

Evaluation of the nutritional value of faba beans with high and low tannin content for use as feed for ruminants

BACKGROUND

Faba bean varieties with low or zero tannin content have been developed in Canada to overcome the negative effects of condensed tannins on the utilization by ruminants of crude protein (CP) and starch. However, their nutritional value has not been evaluated for incorporation in dairy rations. The objectives of this study were to investigate (i) the chemical profile; (ii) the Cornell Net Carbohydrate and Protein System (CNCPS) protein and carbohydrate subfractions; (iii) the energy values; (iv) the ruminal, intestinal, and total digestibility of CP; (v) the metabolizable protein (MP) supply to dairy cows; and (vi) the protein-inherent molecular spectral characteristics of brown-seeded (var. Fatima) faba beans with high tannin content and yellow-seeded (var. Snowbird) faba beans with low tannin content.

RESULTS

The results revealed that Fatima beans had higher (P < 0.001) CP content than Snowbird (324 versus 295 g kg^-1 dry matter (DM)), and lower (P < 0.01) starch content than Snowbird (411 g kg^-1 DM versus 444 g kg^-1 DM). Fatima had a lower (P = 0.001) soluble subfraction (201 g kg^-1 DM versus 220 g kg^-1 DM) and higher (P < 0.05) slowly degradable fiber-bounded (24.9 g kg^-1 DM versus 14.7 g kg^-1 DM) and non-degradable (3.24 g kg^-1 DM versus 0 g kg^-1 DM) CNCPS CP subfractions than Snowbird. Fatima had higher (P = 0.03) MP content (117 g kg^-1 DM versus 111 g kg^-1 DM) and metabolizable energy content (ME) 3.12 Mcal kg^-1 versus 3.10 Mcal kg^-1 ) than Snowbird. Molecular spectral intensities of amide I and II proteins (height and area) of Fatima were higher (P < 0.05) than those of Snowbird, reflecting their higher CP content. The ratio of protein spectral intensities, the amide I : amide II height ratio, and the α-helix : β-sheet height ratio differed (P < 0.05) between the two types of bean, highlighting differences in their inherent protein molecular structures.

CONCLUSION

The (Fatima) faba beans with high condensed tannin content had higher MP and ME content. On average, both Faba beans had higher ME and MP content than barley grains, highlighting their promising nutritional value for dairy rations. © 2021 Society of Chemical Industry.

Faba Bean: An Untapped Source of Quality Plant Proteins and Bioactives

Faba beans are emerging as sustainable quality plant protein sources, with the potential to help meet the growing global demand for more nutritious and healthy foods. The faba bean, in addition to its high protein content and well-balanced amino acid profile, contains bioactive constituents with health-enhancing properties, including bioactive peptides, phenolic compounds, GABA, and L-DOPA. Faba bean peptides released after gastrointestinal digestion have shown antioxidant, antidiabetic, antihypertensive, cholesterol-lowering, and anti-inflammatory effects, indicating a strong potential for this legume crop to be used as a functional food to help face the increasing incidences of non-communicable diseases. This paper provides a comprehensive review of the current body of knowledge on the nutritional and biofunctional qualities of faba beans, with a particular focus on protein-derived bioactive peptides and how they are affected by food processing. It further covers the adverse health effects of faba beans associated with the presence of anti-nutrients and potential allergens, and it outlines research gaps and needs.

Understanding G × E Interaction for Nutritional and Antinutritional Factors in a Diverse Panel of Vigna stipulacea (Lam.) Kuntz Germplasm Tested Over the Locations

Micronutrient malnutrition or hidden hunger is a serious challenge toward societal well-being. Vigna stipulacea (Lam.) Kuntz (known locally as Minni payaru), is an underutilized legume that has the potential to be a global food legume due to its rich nutrient profile. In the present study, 99 accessions of V. stipulacea were tested for iron (Fe), zinc (Zn), calcium (Ca), protein, and phytate concentrations over two locations for appraisal of stable nutrient-rich sources. Analysis of variance revealed significant effects of genotype for all the traits over both locations. Fe concentration ranged from 29.35-130.96 mg kg-1 whereas Zn concentration ranged from 19.44 to 74.20 mg kg-1 across both locations. The highest grain Ca concentration was 251.50 mg kg-1 whereas the highest grain protein concentration was recorded as 25.73%. In the case of grain phytate concentration, a genotype with the lowest value is desirable. IC622867 (G-99) was the lowest phytate containing accession at both locations. All the studied traits revealed highly significant genotypic variances and highly significant genotype × location interaction though less in magnitude than the genotypic variance. GGE Biplot analysis detected that, for grain Fe, Zn, and Ca concentration the 'ideal' genotypes were IC331457 (G-75), IC331610 (G-76), and IC553564 (G-60), respectively, whereas for grain protein concentration IC553521 (G-27) was the most "ideal type." For phytate concentration, IC351407 (G-95) and IC550523 (G-99) were considered as 'ideal' and 'desirable,' respectively. Based on the desirability index, Location 1 (Kanpur) was identified as ideal for Fe, Zn, Ca, and phytate, and for grain protein concentration, Location 2 (New Delhi) was the ideal type. A significant positive correlation was detected between grain Fe as well as grain Zn and protein concentration considering the pooled analysis over both the locations where as a significant negative association was observed between phytate and protein concentration over the locations. This study has identified useful donors and enhanced our knowledge toward the development of biofortified Vigna cultivars. Promoting domestication of this nutrient-rich semi-domesticated, underutilized species will boost sustainable agriculture and will contribute toward alleviating hidden hunger.

Nutritive value of faba bean (Vicia faba L.) as a feedstuff resource in livestock nutrition: A review

The review evaluates faba bean (Vicia faba L.; FB) seeds relative to their nutritional composition, their content of antinutritional factors, and their impact on animal performance. The literature indicates that FB plant is a cool-season, annual grain legume that grows the best in cool and humid conditions. Its seeds are rich in protein, energy, and mineral compounds and have particularly high unsaturated fatty acid levels. However, FB seeds also contain various proportions of antinutritional factors (ANFs) that can interfere with nutrient utilization in nonruminants. The various processing methods are efficient in either reducing or inactivating the ANFs of FB seeds, with extrusion treatment offering the most effective method of improving apparent nutrient and energy digestibility of nonruminants. In vivo studies on ruminants, pigs, poultry, and fishes reveal that FB seeds have the potential to be used as a substitute for soybean meal and/or cereal seeds in livestock diets in order to support milk, meat, and/or egg production.

Phenolic Profiles of Ten Australian Faba Bean Varieties

Although Australia is the largest exporter of faba bean globally, there is limited information available on the levels of bioactive compounds found in current commercial faba bean varieties grown in this country. This study profiled the phenolic acid and flavonoid composition of 10 Australian faba bean varieties, grown at two different locations. Phenolic profiling by HPLC-DAD revealed the most abundant flavonoid to be catechin, followed by rutin. For the phenolic acids, syringic acid was found in high concentrations (72.4-122.5 mg/kg), while protocatechuic, vanillic, p-hydroxybenzoic, chlorogenic, p-coumaric, and trans-ferulic acid were all found in low concentrations. The content of most individual phenolics varied significantly with the variety, while some effect of the growing location was also observed. This information could be used by food processors and plant breeders to maximise the potential health benefits of Australian-grown faba bean.

Exploration of biodegradation traits in dairy cows and protein spectroscopic features in microwaved and moist heated tannin and non-tannin Faba bean

The objective of this study was to explore if microwave irradiation and moist autoclaving treatments could change nutritive values, nutrients availability and protein inherent spectral structural characteristics in tannin (var. Fatima) and non-tannin (var. Snowbird) faba beans. An in situ approach with four cannulated dry Holstein dairy cows was applied in this study. The results showed that beans heated with microwave and autoclaving had increased contents of ether extract and neutral detergent insoluble CP and reduced soluble CP, sugar and tannin concentrations when compared with the raw seeds. Heating reduced degradable nutrients in the rumen and increased intestinally absorbable nutrients, but it failed to improve digestibility in total tract. All the results showed heating with moisture and pressure would be stronger and severer than microwave irradiation. The variety of faba bean interacted with thermal treatment on total truly intestinally absorbed protein value which showed to be highest in the microwaved brown faba bean and lowest in the unheated Snowbird bean. The degraded protein balance (OEB) value was significantly decreased after both kinds of heating process, suggesting that heating treatments could mitigate loss of nitrogen from the rumen to a large extent. We further collected spectral data using mid-IR spectroscopy and found heat processed beans had varied peak height and area ratios compared with raw beans. However, multivariate results implied that heating process failed to completely change the whole molecular conformation in the protein amide region. Correlations were found between ADF/ADL and spectral features, and the OEB value was negatively related to protein secondary structural α-helix. In conclusion, both faba beans were more sensitive to autoclaving treatment than microwave irradiation in terms of nutrient availability in ruminants.

Nutritional and antinutritional composition of fava bean (Vicia faba L., var. minor) cultivars

A dietary shift from resource-demanding animal protein to sustainable food sources, such as protein-rich beans, lowers the climate footprint of food production. In this study, we examined the nutrients and antinutrients in 15 fava bean varieties cultivated in Sweden to select varieties with high nutritional value. On a dry weight basis, the fava beans were analyzed for their content of protein (range 26-33%), amino acids (leucine range: 50.8-72.1 mg/g protein, lysine range: 44.8-74.8 mg/g protein), dietary fiber (soluble fraction range: 0.55-1.06%, insoluble fraction range: 10.7-16.0%), and iron (1.8-21.3 mg/100 g) and zinc contents (0.9-5.2 mg/100 g), as well as for the following antinutrients: lectin (0.8-3.2 HU/mg); trypsin inhibitor (1.2-23.1 TIU/mg) and saponin (18-109 µg/g); phytate (112-1,281 mg/100 g); total phenolic content (1.4-5 mg GAE/g); and vicine(403 µg/g - 7,014 µg/g), convicine (35.5 µg/g - 3,121 µg/g) and the oligosaccharides raffinose (1.1-3.9 g/kg), stachyose (4.4-13.7 g/kg) and verbascose (8-15 g/kg). The results indicate substantial differences between cultivars in relation to their contents of nutrients and antinutrients. Only one of the cultivars studied (Sunrise) have adequate estimated bioavailability of iron, which is of major concern for a diet in which legumes and grains serve as important sources of iron. The nutritional gain from consuming fava beans is significantly affected by the cultivar chosen as the food source.

Revisiting phytate-element interactions: implications for iron, zinc and calcium bioavailability, with emphasis on legumes

Myo-Inositol hexakisphosphate or phytic acid concentration is a prominent factor known to impede divalent element bioavailability in vegetal foods including legumes. Both in vivo and in vitro studies have suggested that phytic acid and other plant-based constituents may synergistically form insoluble complexes affecting bioavailability of essential elements. This review provides an overview of existing investigations on the role of phytic acid in the binding, solubility and bioavailability of iron, zinc and calcium with a focus on legumes. Given the presence of various interference factors within legume matrices, current findings suggest that the commonly adapted approach of using phytic acid-element molar ratios as a bioavailability predictor may only be valid in limited circumstances. In particular, differences between protein properties and molar concentrations of other interacting ions are likely responsible for the observed poor correlations. The role of phytate degradation in element bioavailability has been previously examined, and in this review we re-emphasize its importance as a tool to enhance mineral bioavailability of mineral fortified legume crops. Food processing strategies to achieve phytate reduction were identified as promising tools to increase mineral bioavailability and included germination and fermentation, particularly when other bioavailability promoters (e.g. NaCl) are simultaneously added.

Nutritional and technological assessment of durum wheat-faba bean enriched flours, and sensory quality of developed composite bread

Faba beans are acknowledged as a good source of proteins, minerals, fibers, vitamins and antioxidants. A blending study was undertaken in order to prepare naturally bread from enriched flours with added nutritional value, mainly in terms of Iron and proteins. Enriched flours were prepared with varied levels (25, 30, 35 and 40%) of whole faba bean flour to assess the effects of this substitution on their nutritional and technological properties. Then, whole durum wheat bread (regular) and enriched bread at 40% substitution level (composite bread) were prepared and subjected to sensory evaluation. The substitution level of composite bread was selected on the basis of Iron and proteins contents and technological results of the flour blends. Nutritionally, except for moisture, fibers, fat, zinc and sodium values, significant (p < 0.05) increases were showed in ash, proteins, minerals, total phenolic compounds, condensed tannins, total flavonoids and anti-radical activity values. Technologically, significant (p < 0.05) decreases were recorded for lightness and whiteness index. The gluten strength value revealed a significant (p < 0.05) decrease as whole faba bean flour was added. On the sensory level, the level of substitution (40%) chosen for the manufacture of composite bread resulted in acceptable bread by consumers. Moreover, composite bread was most preferred in aroma as it imparts a feeling of satiety. The observed nutritional improvements could be useful for malnourished people, including those having Iron and proteins deficiencies. Technologically, the observed changes didn’t present limitations since composite bread was accepted by consumers even at 40% substitution level. Besides, the slight preference of composite bread aroma might encourage its consumption by consumers. Also, its promotion of satiety is important for gluten sensitivity sufferers. Our results suggested that 40% is the appropriate ratio to increase, at the same time, Iron and proteins contents of enriched flours as well as their overall nutritional quality. Also it was possible to produce natural composite bread at this level (40%) while maintaining adequate technological and sensory quality.

Variation in the chemical composition and the nutritive quality of different field bean UK-grown cultivar samples for broiler chicks

1. The chemical composition and physical characteristics of 10 different UK-grown field bean cultivar samples from the same harvest year were determined.2. Diets included each bean sample at a level of 200 g/kg, and were used to compare broiler growth performance and determine N-corrected apparent metabolisable energy (AMEn) and nutrient utilisation. The AMEn and nutrient retention coefficients for the bean samples were obtained via the slope-ratio method. The relationships were examined between variation in nutritive value for broilers and the laboratory analysis of the bean samples.3. The data showed significant differences (P < 0.05) among the bean cultivar samples for feed conversion ratio, AMEn and dry matter retention (DMR) coefficients. Further analysis showed that the feeding quality of different field bean cultivar samples, measured as AMEn, was highly correlated to crude protein (CP) (P < 0.05) and colour (P < 0.001) of the samples. Thus, beans with higher CP and pale colour had superior feeding value for broilers.

Comprehensive overview of the quality of plant- And animal-sourced proteins based on the digestible indispensable amino acid score

Indispensable amino acid (IAA) composition and standardized ileal digestibility (SID) of five animal- and 12 plant-based proteins were used to calculate their respective Digestible Indispensable Amino Score (DIAAS) according to the three age categories defined by the Food and Agriculture Organization (FAO). Mean IAA content and mean SID obtained from each protein dataset were subsequently used to simulate optimal nutritional quality of protein mixtures. Datasets revealed considerable variation in DIAAS within the same protein source and among different protein sources. Among the selected protein sources, and based on the 0.5- to 3-year-old reference pattern, pork meat, casein, egg, and potato proteins are classified as excellent quality proteins with an average DIAAS above 100. Whey and soy proteins are classified as high-quality protein with an average DIAAS ≥75. Gelatin, rapeseed, lupin, canola, corn, hemp, fava bean, oat, pea, and rice proteins are classified in the no quality claim category (DIAAS <75). Potato, soy, and pea proteins can complement a broad range of plant proteins, leading to higher DIAAS when supplied in the form of protein mixtures and at specific ratios. Such complementarity highlights the potential to achieve an optimal nutritional efficiency with plant proteins alone.

Effects of faba bean extrusion and phytase supplementation on performance, phosphorus and nitrogen retention, and gut microbiota activity in broilers

BACKGROUND

Faba bean (FB) can be used in poultry diets as a protein source alternative to soybean meal. This study evaluated the effect of extrusion of low-tannin FB and phytase supplementation on performance, phosphorus (P) and nitrogen (N) retention, and gut microbiota activity in broiler chickens. Raw or extruded FB meal was included in broiler diet at 300 g kg^-1 . The experimental treatments additionally differed in nutrient level (adequate, or calcium, P, and protein reduced) and phytase supplementation.

RESULTS

Broiler performance was not affected by the dietary treatments. Extrusion and a reduced nutrient content did not affect P and N retention coefficients, but they increased when the reduced diets were supplemented with phytase. In the ileal digesta, FB extrusion increased the activities of bacterial α- and β-glucosidase, β-galactosidase, and β-glucuronidase, but acetate and total short-chain fatty acids (SCFAs) concentrations were higher only in birds fed extruded FB supplemented with phytase. In the cecal digesta, FB extrusion increased the activities of bacterial α- and β-glucosidase, α-galactosidase and β-glucuronidase, and phytase supplementation decreased β-glucosidase and β-glucuronidase activities, but acetate, butyrate and valerate and total SCFA concentrations were lower in birds fed extruded FB.

CONCLUSION

Good performance of broilers could be obtained using diets containing 300 g kg^-1 raw FB. The extrusion process does not improve FB nutritive value and may negatively affect the activity of cecal microbiota. Phytase supplementation allows lowering calcium, inorganic P, and protein level in diets with FB, and reduces P and N excreted in droppings, with a positive effect on the environment. © 2020 Society of Chemical Industry.

Using advanced vibrational molecular spectroscopy (ATR-Ft/IRS) to study heating process induced changes on protein molecular structure of biodegradation residues in cool-climate adapted faba bean seeds: Relationship with rumen and intestinal protein digestion in ruminant systems

The objective of this study was to evaluate the effects of heating process on protein molecular structure from ruminal degradation residues in cool-climate adapted faba bean seeds in relation to crude protein (CP), in situ degradation kinetics, rumen protein degradation and intestinal protein digestion parameters in dairy cows. Seeds of six faba bean varieties with low (Snowbird, Snowdrop, 219_16) and normal tannin (Fatima, 346_10, SSNS_1) were collected from three different locations, and were heated 3 min by microwave irradiation (MI, dry heating) or heated 1 h by steam pressure toasting (SP, moist heating) or kept raw as a control. Heat treated samples were used for rumen incubating 24, 12, 8, 4, 2, 0 h(s) in two replicate runs and then residues from 12 h of rumen degradation were used for three steps in vitro technique for determining intestinal protein digestion. Attenuated total reflectance Fourier transforms infrared spectroscopy (ATR-Ft/IRS) was used for analyzing protien molecular structure of residual faba bean seeds. The results showed that SP increased the intensities of amide I, amide II, α-helix and β-sheet but decreased amide I to amide II height and area ratio, α-helix to β-sheet height ratio from 12 and 24 h of ruminal degradation, and MI decreased all the intensities of amide I, amide II, α-helix and β-sheet and ratios except amide I to amide II area ratio of residues from 24 h of ruminal degradation. Additionally, the intensities of amide I, amide II, α-helix and β-sheet had a unique pattern of increasing first and then decreasing with the increasing ruminal digestion time for SP treatment, while amide I to amide II height and area ratio, α-helix to β-sheet height ratio were declining. For the MI groups, this pattern was not observed and the intensities were rather consistent across the digestion process. Rumen protein degradation parameters including rumen bypass crude protein (BCP) or rumen undegradable protein (RUP) and rumen degradable protein (RDP) closely correlated with protein molecular structure of to peak heights, areas and ratios. Regression equations based on residual protein molecular structure presented a good estimation power for soluble fraction (S, R² = 0.79), degradable fraction (D, R² = 0.805), BCP (R² = 0.941), RUP (R² = 0.941) and RDP (R² = 0.811). Overall, heat-induced changes in rumen residual protein molecular structures were related to CP, in situ degradation kinetics, rumen protein degradation and rumen protein digestion parameters.

Using advanced vibrational molecular spectroscopy (ATR-Ft/IRS and synchrotron SR-IMS) to study an interaction between protein molecular structure from biodegradation residues and nutritional properties of cool-climate adapted faba bean seeds

The objective of this study was to use advanced vibrational molecular spectroscopy (ATR-Ft/IRS) to study an interaction between legume protein molecular structure from biodegradation residues and nutritional properties of newly developed genotypes of cool-climate adapted faba bean seed with low and normal tannin levels grown in western Canada. Protein molecular structures including amide I, II areas and peak heights, α-helix and β-sheet peak heights in rumen biodegradation residues were determined by using attenuated total reflectance Fourier transform infrared molecular spectroscopy (ATR-FTIR). The nutritional properties were determined which included chemical and nutrient profiles, in situ rumen degradation kinetics, rumen protein degradation, and intestinal protein digestion in the newly developed genotypes of faba bean seeds with low and normal tannin levels. The results showed that the spectral intensity of faba bean varieties with a normal tannin level in rumen biodegradation residues was greater (P < 0.05) than that with a low tannin level. The spectral intensity of amide I, II areas and peak heights, α-helix and β-sheet peak heights in all genotypes (except the variety of Snowdrop) in biodegradation residuals of faba bean seeds had a unique pattern with increasing first and then decreasing with the increasing of rumen incubation time. The molecular structures of protein (α-helix, ratio of α-helix to β-sheet height and amide I to II area, R² > 0.6) were associated with in situ degradation kinetics - soluble (S) and potential degradable fractions (D) and rumen protein degradation- bypass or undegraded protein (BCP or RUP). The molecular spectral parameters in the FTIR fingerprint region didn't form cluster among different genotypes in residual faba bean seeds in 12 h and 24 h incubation, which indicate they had similar protein molecular structures after incubation. In conclusion, there was an interaction between protein molecular structure from biodegradation residues and nutritional properties of newly developed cool-climate adapted faba bean seeds with normal and low level of tannin. The cool-climate adapted genotype had an impact on the protein molecular structure, and the protein utilization and metabolism were predictable from protein spectral molecular structures after rumen biodegradation with ATR-Ft/IRS spectroscopy.

Improving pulse crops as a source of protein, starch and micronutrients

Pulse crops have been known for a long time to have beneficial nutritional profiles for human diets but have been neglected in terms of cultivation, consumption and scientific research in many parts of the world. Broad dietary shifts will be required if anthropogenic climate change is to be mitigated in the future, and pulse crops should be an important component of this change by providing an environmentally sustainable source of protein, resistant starch and micronutrients. Further enhancement of the nutritional composition of pulse crops could benefit human health, helping to alleviate micronutrient deficiencies and reduce risk of chronic diseases such as type 2 diabetes. This paper reviews current knowledge regarding the nutritional content of pea (Pisum sativum L.) and faba bean (Vicia faba L.), two major UK pulse crops, and discusses the potential for their genetic improvement.

Unravelling the phytonutrients and antioxidant properties of European Vicia faba L. seeds

For the first time, seven European varieties of Vicia faba L. seeds were investigated for (1) their phytonutrients profile by HPLC-DAD-MS/MS, (2) total phenolic content (TPC), and (3) antioxidant capacity (DPPH and FRAP assays). A wide range of compounds were identified, namely alkaloids, organic acids, terpenoids, jasmonates, and phenolics; these two latter being the most abundant. TPC ranged between 2.62 and 4.3 mg (gallic acid equivalent) g^-1 dry weight, for V. faba major variety Belshi and V. faba minor variety Bauska, respectively. The DPPH radical scavenging capacity showed poor correlation (r = 0.550, P = .041) with TPC, suggesting the presence of other antioxidant sources than phenolics. Still, FRAP was positively correlated with TPC (r = 0.709, P < .01) and DPPH (r = 0.819, P < .01). These results elucidated the phytonutrients and antioxidant properties of V. faba L. seeds as functional food sources.

Gut-bone axis response to dietary replacement of soybean meal with raw low-tannin faba bean seeds in broiler chickens

It seems that faba bean (FB) seeds could be a good protein-energy component in animal feed, but the presence of anti-nutritional substances limits their use as a substitute of soybean meal. The aim of the study was to examine the influence of different concentrations of raw, low-tannin, FB seeds on the gut-bone axis in Ross 308 broilers. One-day old chickens were randomly subjected to one of the 3 dietary treatments: the control group was fed standard diet based on soybean meal and without FB seeds, and two groups were fed 8%/15% and 16%/22% of raw low-tannin FB seeds in the starter and grower, respectively. On the 35th day, hematological and serum biochemical analyses as well histomorphometry of the small intestine and liver tissue and bone mechanical tests were performed. The diet type had no effect on the body weight gain and feed conversion ratio. However, the basal intestinal structures were significantly reduced in birds fed the lower concentration of FB. The enlargement of nerve plexuses was dependent on the concentration used in the diet and, additionally, on the kind of plexus and location in the intestinal tract. The liver was characterized by an increase in non-hepatocytes. There was no influence of the low-tannin FB seeds on most of the analyzed serum parameters in the 35-day-old broiler chickens, except the decreased concentration of total cholesterol and Ca in both experimental groups, triglycerides in group I, and P and uric acid in group II. Furthermore, the increasing concentration of the dietary low-tannin FB did not influence the activities of AspAT (except the group fed the higher amount of FB), ALAT, and LDH. The broiler chickens had no visible leg lesions and no problem in the locomotor function, but the tibiae were lighter mainly in birds fed the higher concentration of FB seeds. Geometric analysis revealed reduction of the cross section area and wall thickness, indicating a decline in the bone midshaft, which influenced the densitometric parameters and the results of mechanical tests. In conclusion, the dietary inclusion of raw low-tannin FB seeds had no negative effects on broiler growth, but disturbed the intestine structure and tibia characteristics. Therefore, all these negative effects necessitate additional examinations before inclusion of raw low-tannin FB seed into poultry diet.

Mechanism of Calcium Lactate Facilitating Phytic Acid Degradation in Soybean during Germination

Calcium lactate facilitates the growth and phytic acid degradation of soybean sprouts, but the mechanism is unclear. In this study, calcium lactate (Ca) and calcium lactate with lanthanum chloride (Ca+La) were used to treat soybean sprouts to reveal the relevant mechanism. Results showed that the phytic acid content decreased and the availability of phosphorus increased under Ca treatment. This must be due to the enhancement of enzyme activity related to phytic acid degradation. In addition, the energy metabolism was accelerated by Ca treatment. The energy status and energy metabolism-associated enzyme activity also increased. However, the transmembrane transport of calcium was inhibited by La(3+) and concentrated in intercellular space or between the cell wall and cell membrane; thus, Ca+La treatment showed reverse results compared with those of Ca treatment. Interestingly, gene expression did not vary in accordance with their enzyme activity. These results demonstrated that calcium lactate increased the rate of phytic acid degradation by enhancing growth, phosphorus metabolism, and energy metabolism.

Effects of ABA and CaCl2 on GABA accumulation in fava bean germinating under hypoxia-NaCl stress

Effects of exogenous abscisic acid (ABA) and CaCl2 on γ-aminobutyric acid (GABA) accumulation of germinated fava bean under hypoxia-NaCl stress were investigated. Exogenous ABA resulted in the enhancement of glutamate decarboxylase (GAD) and diamine oxidase (DAO) activity as well as GABA content in cotyledon and shoot. CaCl2 increased both enzyme activities in shoot and GABA content in cotyledon and shoot. ABA downregulated GAD expression in cotyledon and radicle, while upregulated that in shoot; it also upregulated DAO expression in each organ. CaCl2 upregulated GAD expression in cotyledon, while downregulated that in radicle. However, it upregulated DAO expression in shoot, downregulated that in radicle. ABA inhibitor fluridon and ethylenediaminetetraacetic acid inhibited GAD and DAO activities significantly so that inhibited GABA accumulation through reducing ABA biosynthesis and chelating Ca2+, respectively. However, they upregulated GAD and DAO expression in varying degrees. These results indicate that ABA and Ca2+ participate in GABA biosynthesis in fava bean during germination under hypoxia-NaCl stress.

Faba Bean: Transcriptome Analysis from Etiolated Seedling and Developing Seed Coat of Key Cultivars for Synthesis of Proanthocyanidins, Phytate, Raffinose Family Oligosaccharides, Vicine, and Convicine

Faba bean (Vicia faba L.) has been little examined from a genetic or genomic perspective despite its status as an established food and forage crop with some key pharmaceutical factors such as vicine and convicine (VC), which provoke severe haemolysis in genetically susceptible humans. We developed next-generation sequencing libraries to maximize information to elucidate the VC pathway or relevant markers as well as other genes of interest for the species. One selected cultivar, A01155, lacks synthesis of the favism-provoking factors, VC, and is low in tannin, while two cultivars, SSNS-1 and CDC Fatima, are wild-type for these factors. Tissues (5- to 6-d-old root and etiolated shoot and developing seed coat) were selected to maximize the utility and breadth of the gene expression profile. Approximately 1.2 × 10⁶ expressed transcripts were sequenced and assembled into contigs. The synthetic pathways for phosphatidylinositol or phytate, the raffinose family oligosaccharides, and proanthocyanidin were examined and found to contain nearly a full complement of the synthetic genes for these pathways. A severe deficiency in anthocyanidin reductase expression was found in the low-tannin cultivar A01155. Approximately 5300 variants, including 234 variants specific to one of the three cultivars, were identified. Differences in expression and variants potentially related to VC synthesis were analyzed using strategies exploiting differences in expression between cultivars and tissues. These sequences should be of high utility for marker-assisted selection for the key traits vicine, convicine, and proanthocyanidin, and should contribute to the scant genetic maps available for this species.

Sequence analysis of diamine oxidase gene from fava bean and its expression related to γ-aminobutyric acid accumulation in seeds germinating under hypoxia-NaCl stress

BACKGROUND

γ-Aminobutyric acid (GABA) is synthesized via the polyamine degradation pathway in plants, with diamine oxidase (DAO) being the key enzyme. In this study the cDNA of DAO in fava bean was cloned and its expression in seeds germinating under hypoxia-NaCl stress was investigated.

RESULTS

Fava bean DAO cDNA is 2199 bp long and contains 2025 bp of open reading frame that encodes 675 amino acid peptides with a calculated molecular weight of 76.31 kDa and a pI of 5.41. Hypoxia and hypoxia-NaCl stress enhanced DAO activity and resulted in GABA accumulation in germinating fava bean. However, DAO gene expression was down-regulated under hypoxia compared with non-stress condition, while its expression in the cotyledon and shoot was up-regulated under hypoxia-NaCl. In addition, DAO expression could be promoted to enhance GABA accumulation after increasing the stress intensity using NaCl. DAO gene expression was significantly inhibited by aminoguanidine treatment under hypoxia but increased under hypoxia-NaCl.

CONCLUSION

Under hypoxia, GABA accumulation due to NaCl was mainly concentrated in the cotyledon. The GABA content increase under hypoxia did not result from DAO gene expression, but DAO existing in seeds was activated under hypoxia. DAO gene expression was up-regulated to enhance GABA accumulation after increasing the stress intensity.

Effects of roasting on phenolic composition and in vitro antioxidant capacity of Australian grown faba beans (Vicia faba L.)

Faba bean phenolic compounds encompassed phenolic acids, flavonols, proanthocyanidins and anthocyanins. Roasting faba beans for 120 min decreased the total phenolic, flavonoid and proanthocyanidin contents by 42, 42 and 30%, respectively. Roasting beans for 120 min decreased the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, total equivalent antioxidant capacity and ferric reducing antioxidant power by 48, 15 and 8%, respectively. High performance liquid chromatography-post column derivatisation revealed the generation of new phenolic compounds as a result of roasting. Antioxidant mechanism of bean less-polar phenolic compounds was largely based on free radical scavenging activity. The bean phenolic compounds with reducing capability were heat stable. Roasted faba bean extracts (70% acetone, v/v) were fractionated into relatively polar and non-polar fractions; the latter contributed the majority of the antioxidant capacity. The extracts from beans with different seed coat colours differed in their phenolic compositions, which suggest different levels of potential benefits to health. Although roasting initially lowers the bean antioxidant capacity, prolonged roasting at 150 °C for 60 min and longer causes generation of new phenolic compounds and an increased antioxidant capacity. The findings encourage a wider ultilisation of faba beans for human foods particularly in baked/roasted products.

Headspace volatile components of Canadian grown low-tannin faba bean (Vicia faba L.) genotypes

BACKGROUND

As flavor is a prerequisite for palatability of new crop varieties, 13 Canadian-grown, low-tannin faba bean genotypes were evaluated for volatile components isolated with headspace solid-phase microextraction, and analyzed with gas chromatography-mass spectrometry.

RESULTS

A total of 45 volatiles consisting of aldehydes, aromatic hydrocarbons, alcohols, ketones and alkanes represented on average 57, 15, 14, 5 and 4.5% of the total peak area, respectively. Total extractable volatiles were highly location dependent, whereas 10 headspace volatiles (1-pentanol, 1-hexanol, pentanal, (E)-2-heptenal, 2-ethylfuran, 2-pentylfuran, acetone, 2-butanone, 2-heptanone and 3-octen-2-one) were genotype specific and/or regulated by environmental conditions. Multivariate data analysis performed on the functional group of the volatiles using principal component analysis and cluster analysis demonstrates that the total extractable volatiles were the major factor segregating faba bean genotypes.

CONCLUSION

The solid-phase microextraction technique proved to be a rapid and effective method for routine evaluation of faba bean volatile profile that may be applicable in a screening/plant breeding program.

Phenolics content and antioxidant and anti-inflammatory activities of legume fractions

Two faba bean (Vicia faba L.) subspecies major and minor and lentil seeds grown in Algeria were separated into cotyledons and hulls. These fractions, together with their corresponding whole seeds, were extracted with two solvents, aqueous (70%) acetone and (80%) ethanol, and evaluated for antioxidant activity in relation to their phenolic contents. Acetone selectively extracted tannins from faba beans. The hulls always exhibited high antioxidant activity, measured using the reducing power (RP), antiradical activity (DPPH) or oxygen radical absorbance capacity (ORAC) assays. Aqueous ethanol (80%) extract of lentil hulls exhibited high antioxidant and anti-inflammatory activities preferentially inhibiting 15-LOX (IC(50), 55 μg/ml), with moderate COX-1 (IC(50), 66 μg/ml) and COX-2 (IC(50), 119 μg/ml) inhibitory effects on the COX pathway, whereas faba bean hull extracts exerted relatively mild LOX inhibitory activity.

Application of bifidobacterial phytases in infant cereals: effect on phytate contents and mineral dialyzability

Phytase activity was recently described in probiotic bifidobacterial strains, opening the possibilities for their use in foods, due to the generally regarded as safe/qualified presumption of safety status of these bacteria. Two raw materials for infant cereals (multicereal and gluten-free) were examined by measuring the myo-inositol phosphates content and the in vitro Ca, Fe, and Zn availability after a dephytinization process with purified phytases from Bifidobacterium longum spp. infantis and Bifidobacterium pseudocatenulatum. Treatment with both enzymes reduced the contents of phytate as compared to control samples (untreated or treated with fungal phytase) and led to increased levels of myo-inositol triphosphate. Dephytinization followed by an in vitro model of intestinal digestion increased the solubility of Zn. However, phytase treatment did not increase significantly the mineral dialyzability as compared to untreated samples. This is the first example of the application of purified bifidobacterial phytases in food processing and shows the potential of these enzymes to be used in products for human consumption.

GABA shunt and polyamine degradation pathway on γ-aminobutyric acid accumulation in germinating fava bean (Vicia faba L.) under hypoxia

GABA shunt and polyamine degradation pathway on γ-aminobutyric acid (GABA) accumulation in germinating fava bean under hypoxia was investigated. GABA content, GAD and DAO activity were significantly increased under hypoxia treatment. Glu and polyamine contents enhanced largely and thus supplied as sufficient substrates for GABA formation. In contrast, GABA content decreased, mainly in the embryo, after removing the hypoxia stress. DAO activity, Glu and polyamines contents decreased, while an increment of GAD activity was observed. This indicated that GAD activity can be not only regulated by hypoxia, but by the rapid growth of embryo after the recovery from hypoxia stress. When treated with AG, DAO activity was almost inhibited completely, and the GABA content decreased by 32.96% and 32.07% after treated for 3 and 5 days, respectively. Hence, it can be inferred that about 30% of GABA formed in germinating fava bean under hypoxia was supplied by polyamine degradation pathway.