Composição química do feijão caupi (Vigna unguiculata L. Walp), cultivar BRS-Milênio

Weed-Hoeing Periods in Cowpea Cultivation under Direct and Conventional Systems

Weed coexistence with an agricultural crop can negatively affect its growth, development, and yield. From this perspective, this study aimed to evaluate weed management strategies and their effect on the agronomic parameters of cowpea cultivation in direct (SPD) and conventional (SPC) planting systems. The experiment was set up in a completely randomized block design with a split-plot arrangement with four replications. The plots received a source of variation referring to the planting systems (direct and conventional planting), and the subplots corresponded to ten weed management strategies (manual hoeing 18 days after planting (DAP); at 36 DAP; at 54 DAP; at 18 and 36 DAP; at 18 and 54 DAP; at 18 and 72 DAP; at 36 and 54 DAP; at 36-72 DAP; at 18, 36, and 54 DAP; and a control with no hoeing). Density and dry mass evaluations of the cowpea plants were performed at harvest (72 DAP) by determining the number of pods per plant, pod length, number of grains per pod, 1000-grain mass, and yield. A total of 28 species distributed in 12 botanical families were identified in the two cultivation systems. The family Poaceae showed the highest frequency, with 25% of the species identified. At the end of the assay, treatment 20 had the highest positive influence and provided significant quantitative gains to the complex of traits related to cowpea production (SPD and hoeing at 18, 36, and 54 DAP). UPGMA cluster analysis and canonical discriminant analysis were performed and allowed a better classification of the evaluated treatments. It was observed that the first two canonical variables explained 90.8% of the total variance contained in the original variables. The use of SPD with weeding at 18, 36, and 54 days after planting provides greater weed control and significant quantitative gains for the complex of characteristics related to cowpea production. The results underscore the importance of choosing the correct cropping system and implementing effective weeding practices to optimize weed control and improve crop performance.

Association between Polyphenol Intake and Lipid Profile of Adults and Elders in a Northeastern Brazilian Capital

This research was aimed at evaluating the relationship between the estimated polyphenol intake and the atherogenic lipid profile in adult and elder residents in the city of Teresina, located in the Northeastern Region of Brazil. This study was a cross-sectional population-based survey with 501 adults and elders, conducted in Teresina, Brazil. Food intake was obtained by 24-h food recall. The estimated polyphenol intake was calculated by multiplying the food consumption data from the recall by the polyphenol content in the foods described in the Phenol-Explorer database. The mean intake of total polyphenols was 1006.53 mg/day. The phenolic acids was the class with the highest intake, followed by the flavonols. Coffee, beans and apples were the main foods contributing to the total polyphenol intake. In the individuals with elevated serum concentrations of total cholesterol and triglycerides, the intake of total polyphenols was significantly higher. The intake of total polyphenols, phenolic acids and lignans was higher in the subjects with dyslipidemia. This article provides, for the first time, data on the intake of the total polyphenol classes and subclasses in the evaluated population and the relationship with the lipid profile. The individuals with a higher intake of total polyphenols had a worse lipid profile, which may be a consequence of an improved diet in those individuals who present with dyslipidemia.

Comparison of grain protein profiles of Brazilian cowpea (Vigna unguiculata) cultivars based on principal component analysis

This study aims to compare the grain protein profile of four Brazilian cowpea cultivars (BRS Aracê, BRS Itaim, BRS Pajeú, and BRS Xiquexique) by two-dimensional electrophoresis (2-DE) and principal component analysis (PCA). 2-DE efficiently separate cowpea protein profiles, showing high homogeneity among the four cultivars. In addition, the principal component analysis indicated that there is a difference in abundance of proteins among the cultivars. The cultivars BRS Aracê and BRS Xiquexique, both biofortified in iron and zinc, were separated from the cultivars BRS Itaim and BRS Pajeú. These results demonstrate that protein profiles can be used to discriminate cowpea varieties.

Graphical Abstract

Determination of oil composition of cowpea (Vigna unguiculata L.) seeds under influence of organic fertilizer forms

This research was carried out to determine the effects of different organic fertilizer forms on important quality elements of cowpea (Vigna unguiculata L.) seeds. The experiment was conducted according to the completely randomized blocks experimental design with three replications. In the experiment, palmitic acid (PALA), stearic acid (SA), and behenic acid (BA) from saturated fatty acids and palmitoleic acid (PLA), oleic acid (OA), linoleic acid (LA), and linolenic acid (LNA) ratios from unsaturated fatty acids were investigated. Besides these, quality factor such as oleic acid/linoleic acid (O/L) ratio, which is one of the oil stability values and iodine value (IV), unsaturated fatty acids/saturated fatty acids (USFA/SFA) ratio, and oil ratio and oil yield were investigated. As a result of these applications, the values of crude oil yield 27.08–40.68 kg ha−1 and some important quality properties of crude oil ratios 0.75–1.09%, PLA 0.250–0.372%, OA 12.00–22.85%, LA 22.97–29.97%, LNA 19.37–26.01%, PALA 19.53–23.53%, SA 5.27–7.04%, BA 1.86–2.37%, O/L acid ratio 0.402–1.043%, IV 113.73–136.76, and USFA/SFA ratio 2.08–2.74 were obtained.

Nutritional and Food Composition Survey of Major Pulses Toward Healthy, Sustainable, and Biofortified Diets

The world's food demand is increasing rapidly due to fast population growth that has posed a challenge to meeting the requirements of nutritionally balanced diets. Pulses could play a major role in the human diet to combat these challenges and provide nutritional and physiological benefits. Pulses such as chickpeas, green gram, peas, horse gram, beans, lentils, black gram, etc., are rich sources of protein (190–260 g kg−1), carbohydrates (600–630 g kg−1), dietary fibers, and bioactive compounds. There are many health benefits of phytochemicals present in pulses, like flavonoids, phenolics, tannins, phytates, saponins, lectins, oxalates, phytosterols peptides, and enzyme inhibitors. Some of them have anti-inflammatory, anti-ulcerative, anti-microbial, and anti-cancer effects. Along with these, pulses are also rich in vitamins and minerals. In this review, we highlight the potential role of pulses in global food systems and diets, their nutritional value, health benefits, and prospects for biofortification of major pulses. The food composition databases with respect to pulses, effect of processing techniques, and approaches for improvement of nutritional profile of pulses are elaborated.

Genetic architecture of salt tolerance in a Multi-Parent Advanced Generation Inter-Cross (MAGIC) cowpea population

Background

Previous reports have shown that soil salinity is a growing threat to cowpea production, and thus the need for breeding salt-tolerant cowpea cultivars. A total of 234 Multi-Parent Advanced Generation Inter-Cross (MAGIC) lines along with their 8 founders were evaluated for salt tolerance under greenhouse conditions. The objectives of this study were to evaluate salt tolerance in a multi-parent advanced generation inter-cross (MAGIC) cowpea population, to identify single nucleotide polymorphism (SNP) markers associated with salt tolerance, and to assess the accuracy of genomic selection (GS) in predicting salt tolerance, and to explore possible epistatic interactions affecting salt tolerance in cowpea. Phenotyping was validated through the use of salt-tolerant and salt-susceptible controls that were previously reported. Genome-wide association study (GWAS) was conducted using a total of 32,047 filtered SNPs. The epistatic interaction analysis was conducted using the PLINK platform.

Results

Results indicated that: (1) large variation in traits evaluated for salt tolerance was identified among the MAGIC lines, (2) a total of 7, 2, 18, 18, 3, 2, 5, 1, and 23 were associated with number of dead plants, salt injury score, leaf SPAD chlorophyll under salt treatment, relative tolerance index for leaf SPAD chlorophyll, fresh leaf biomass under salt treatment, relative tolerance index for fresh leaf biomass, relative tolerance index for fresh stem biomass, relative tolerance index for the total above-ground fresh biomass, and relative tolerance index for plant height, respectively, with overlapping SNP markers between traits, (3) candidate genes encoding for proteins involved in ion transport such as Na+/Ca2+ K+ independent exchanger and H+/oligopeptide symporter were identified, and (4) epistatic interactions were identified.

Conclusions

These results will have direct applications in breeding programs aiming at improving salt tolerance in cowpea through marker-assisted selection. To the best of our knowledge, this study was one of the earliest reports using a MAGIC population to investigate the genetic architecture of salt tolerance in cowpea.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08332-y.

Loci discovery, network-guided approach, and genomic prediction for drought tolerance index in a multi-parent advanced generation intercross (MAGIC) cowpea population

Cowpea is a nutrient-dense legume that significantly contributes to the population's diet in sub-Saharan Africa and other regions of the world. Improving cowpea cultivars to be more resilient to abiotic stress such as drought would be of great importance. The use of a multi-parent advanced generation intercross (MAGIC) population has been shown to be efficient in increasing the frequency of rare alleles that could be associated with important agricultural traits. In addition, drought tolerance index has been reported to be a reliable parameter for assessing crop tolerance to water-deficit conditions. Therefore, the objectives of this study were to evaluate the drought tolerance index for plant growth habit, plant maturity, flowering time, 100-seed weight, and grain yield in a MAGIC cowpea population, to conduct genome-wide association study (GWAS) and identify single nucleotide polymorphism (SNP) markers associated with the drought tolerance indices, to investigate the potential relationship existing between the significant loci associated with the drought tolerance indices, and to conduct genomic selection (GS). These analyses were performed using the existing phenotypic and genotypic data published for the MAGIC population which consisted of 305 F8 recombinant inbred lines (RILs) developed at University of California, Riverside. The results indicated that: (1) large variation in drought tolerance indices existed among the cowpea genotypes, (2) a total of 14, 18, 5, 5, and 35 SNPs were associated with plant growth habit change due to drought stress, and drought tolerance indices for maturity, flowering time, 100-seed weight, and grain yield, respectively, (3) the network-guided approach revealed clear interactions between the loci associated with the drought tolerance traits, and (4) the GS accuracy varied from low to moderate. These results could be applied to improve drought tolerance in cowpea through marker-assisted selection (MAS) and genomic selection (GS). To the best of our knowledge, this is the first report on marker loci associated with drought tolerance indices in cowpea.

Mead Production by Saccharomyces cerevisiae Safbrew T-58 and Saccharomyces bayanus (Premier Blanc and Premier Cuvée): Effect of Cowpea (Vigna unguiculata L. Walp) Extract Concentration

This work evaluated the effect of the cowpea (Vigna unguiculata L. Walp) extract concentration on mead production. Fermentations were carried out in 500-mL Erlenmeyer flasks containing 250 mL of honey wort (30 °Brix), supplemented with 1 g L^-1 of ammonium sulfate and 0.1 g L^-1 of magnesium chloride and the cowpea extract (5 and 30 g L^-1), inoculated with 10⁶ cells mL^-1, and incubated at 30 °C for 240 h. Higher cell growth ((cells mL^-1): 11.1 × 10⁷, 11.3 × 10⁷, and 19.6 × 10⁷; substrate consumption (%): 86.0, 90.0, and 85.0) and ethanol production ((v v^-1 %): 15.0, 15.5, and 14.1) for yeasts Safbrew T-58, Premier Blanc, and Premier Cuvée, respectively, were obtained with 30 g L^-1 of bean extract. S. bayanus Premier Blanc had the best metabolic activity with lowest glycerol production (8.5 g L^-1) and highest ethanol volumetric yields (0.51-1.52 h^-1) after 48 h of fermentation.

Bioaccessibility and bioavailability of iron in biofortified germinated cowpea

BACKGROUND

Cowpea (Vigna unguiculata L. Walph) is predominantly consumed in the North and Northeast regions of Brazil, and its biofortification with iron seeks to reduce the high prevalence of iron deficiency anemia in these regions. It is commonly eaten cooked; however, in the germinated form, it can improve nutritional quality by reducing the antinutritional factors and consequently improving the bioavailability of elements. The present study aimed to determine the physico-chemical characteristics, bioaccessibility and bioavailability of iron in biofortified germinated cowpea.

RESULTS

There was no statistical difference between the germinated and cooked beans with regard to centesimal composition. Germinated beans had phytates and tannins similar to cooked beans. The phytate-iron molar ratio for all groups did not present a statistical difference (cooking 3.58 and 3.41; germinated 3.94 and 3.51), nor did the parameters evaluating in vivo iron bioavailability. Total phenolics was higher in the germinated group (cooking 0.56 and 0.64; Germinated 2.05 and 2.45 mg gallic acid kg^-1 ). In vitro bioaccessibility of iron of germinated beans presented higher values (P ≤ 0.05) compared to cooked beans. There was higher expression of divalent metal transporter-1 in biofortified and germinated beans.

CONCLUSION

The iron bioavailability from the biofortified and germinated beans was comparable to ferrous sulfate. Germination can be considered as an alternative and efficient method for consuming cowpea, presenting good iron bioaccessibility and bioavailability. © 2019 Society of Chemical Industry.

Brassinosteroids improve photosystem II efficiency, gas exchange, antioxidant enzymes and growth of cowpea plants exposed to water deficit

Water deficit is considered the main abiotic stress that limits agricultural production worldwide. Brassinosteroids (BRs) are natural substances that play roles in plant tolerance against abiotic stresses, including water deficit. This research aims to determine whether BRs can mitigate the negative effects caused by water deficiency, revealing how BRs act and their possible contribution to increased tolerance of cowpea plants to water deficit. The experiment was a factorial design with the factors completely randomised, with two water conditions (control and water deficit) and three levels of brassinosteroids (0, 50 and 100 nM 24-epibrassinolide; EBR is an active BRs). Plants sprayed with 100 nM EBR under the water deficit presented significant increases in ΦPSII, qP and ETR compared with plants subjected to the water deficit without EBR. With respect to gas exchange, PN, E and gs exhibited significant reductions after water deficit, but application of 100 nM EBR caused increases in these variables of 96, 24 and 33%, respectively, compared to the water deficit + 0 nM EBR treatment. To antioxidant enzymes, EBR resulted in increases in SOD, CAT, APX and POX, indicating that EBR acts on the antioxidant system, reducing cell damage. The water deficit caused significant reductions in Chl a, Chl b and total Chl, while plants sprayed with 100 nM EBR showed significant increases of 26, 58 and 33% in Chl a, Chl b and total Chl, respectively. This study revealed that EBR improves photosystem II efficiency, inducing increases in ΦPSII, qP and ETR. This substance also mitigated the negative effects on gas exchange and growth induced by the water deficit. Increases in SOD, CAT, APX and POX of plants treated with EBR indicate that this steroid clearly increased the tolerance to the water deficit, reducing reactive oxygen species, cell damage, and maintaining the photosynthetic pigments. Additionally, 100 nM EBR resulted in a better dose-response of cowpea plants exposed to the water deficit.

Peptides from cowpea present antioxidant activity, inhibit cholesterol synthesis and its solubilisation into micelles

In previous studies, it was reported that the protein isolated from the cowpea interferes favourably in lipid metabolism, and reduces cholesterol synthesis. The present study investigated the role of cowpea peptide fractions in the micellar solubilisation of cholesterol, in the 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) activity, and in the in vitro antioxidant capacity, considering the effects of thermal processing. The protein was isolated from the raw and cooked beans and digested to simulate human digestion. The peptides from the protein isolate of raw bean with molecular mass lower than 3kDa reduced 89% of the HMGCR enzymatic reaction velocity. The cooked cowpeas were more effective in inhibiting the micellar solubility of cholesterol than the raw ones but not the antioxidant activity. This is the first report that cowpea peptides inhibit cholesterol homeostasis in vitro in two distinct routes, and act as an antioxidant.

Utilização da farinha de feijão-caupi (Vigna unguiculata L. Walp) na elaboração de produtos de panificação

Este trabalho teve como objetivo enriquecer produtos de panificação do tipo biscoito e rocambole com farinha de feijão-caupi (FFC), avaliar sua aceitabilidade e composição química, incluindo o conteúdo dos minerais (ferro, zinco, magnésio, potássio e fósforo) e das vitaminas (tiamina e piridoxina). Foram desenvolvidas três formulações de biscoito contendo 10, 20 e 30% FFC e duas formulações de rocambole contendo 10 e 20% FFC. Observou-se um aumento no teor protéico do biscoito 30% FFC e do rocambole 20% FFC e na quantidade de cinzas dos biscoitos 20 e 30% FFC e rocambole 20% FFC, quando comparados às formulações padrão. O teor dos minerais analisados e de piridoxina aumentou à medida que FFC foi adicionada, enquanto a concentração de tiamina aumentou somente no rocambole 20% FFC. O biscoito com 10% FFC apresentou maior aceitação (84,4%), dentre os biscoitos formulados com FFC, além disso, os rocamboles com 10 e 20% FFC tiveram boa aceitação (86,7 e 77,8%, respectivamente). Todas as formulações contendo FFC tiveram notas superiores a 6, mostrando que os produtos foram aceitos sensorialmente. Desta forma, a adição de FFC visando melhorar o valor nutritivo de formulações à base de cereais é viável.

Cholesterol-lowering properties of whole cowpea seed and its protein isolate in hamsters

Hypercholesterolemic hamsters were fed for 4 wk on diets rich in saturated fatty acids and cholesterol, differing only in protein source (20 %): casein (control group, HC), whole cowpea seed (HWS), and cowpea protein isolate (HPI). Hamsters fed on HWS and HPI presented significant reductions in plasma total cholesterol and non-HDL cholesterol. HPI and HC presented similar protein digestibility, which were significantly higher than that of HWS. Animals fed on HWS presented significantly higher levels of bile acids and cholesterol in feces than did the animals fed on casein or HPI diets. Histological analyses of the liver showed that HC diet resulted in steatosis widely distributed throughout the hepatic lobule, while HWS and HPI diets promoted reductions in liver steatosis. The effectiveness of HWS for modulating lipid metabolism was greater than that of HPI, as measured by plasma cholesterol reduction and liver steatosis.