One-Step Purification Strategy for Cowpea Chlorotic Mottle Virus-Like Particles Produced by the IC-BEVS.

Virus-like particles (VLP) of the cowpea chlorotic mottle virus (CCMV), a plant virus, have been shown to be safe and noncytotoxic vehicles for delivering various cargos, including nucleic acids and peptides, and as scaffolds for presenting epitopes. Thus, CCMV-VLP have acquired increasing attention to be used in fields such as gene therapy, drug delivery, and vaccine development. Regardless of their production method, most reports purify CCMV-VLP through a series of ultracentrifugation steps using sucrose density gradient ultracentrifugation, which is a complex and time-consuming process. Here, the use of anion exchange chromatography is described as a one-step protocol for purification of CCMV-VLP produced by the insect cell-baculovirus expression vector system (IC-BEVS).

The elite strain INPA03-11B approved as a cowpea inoculant in Brazil represents a new Bradyrhizobium species and it has high adaptability to stressful soil conditions.

The strain INPA03-11BT, isolated in the 1980s from nodules of Centrosema sp. collected in Manaus, Amazonas, Brazil, was approved by the Brazilian Ministry of Agriculture as a cowpea inoculant in 2004. Since then, several studies have been conducted regarding its phenotypic, genetic, and symbiotic characteristics under axenic and field conditions. Phenotypic features demonstrate its high adaptability to stressful soil conditions, such as tolerance to acidity, high temperatures, and 13 antibiotics, and, especially, its high symbiotic efficiency with cowpea and soybean, proven in the field. The nodC and nifH phylogenies placed the INPA strain in the same clade as the species B. macuxiense BR 10303T which was also isolated from the Amazon region. The sequencing of the 16S rRNA ribosomal gene and housekeeping genes, as well as BOX-PCR profiles, showed its potential as a new species, which was confirmed by a similarity percentage of 94.7% and 92.6% in Average Nucleotide Identity with the closest phylogenetically related species Bradyrhizobium tropiciagri CNPSo1112T and B. viridifuturi SEMIA690T, respectively. dDDH values between INPA03-11BT and both CNPSo 1112T and SEMIA690T were respectively 58.5% and 48.1%, which are much lower than the limit for species boundary (70%). Therefore, we propose the name Bradyrhizobium amazonense for INPA03-11BT (= BR3301 = SEMIA6463).

Evaluation of the Physical, Chemical, Technological, and Sensorial Properties of Extrudates and Cookies from Composite Sorghum and Cowpea Flours.

In recent years, there has been a growing demand for gluten-free and functional products, driven by consumer preferences for healthier and more diverse food choices. Therefore, there is a need to explore new ingredients that can be used as alternatives to traditional gluten-containing grains. Thus, this work evaluated the physical, chemical, technological, and sensorial properties of extrudates and cookies from composite tannin sorghum (rich in resistant starch) and white cowpea flours. Extrudates and cookies were produced from a composite flour made of sorghum and cowpea, at a sorghum:cowpea flour ratio of 70:30, 50:50, and 30:70. Then, raw flours, cookies, and extrudates were characterized (dietary fiber, resistant starch, proteins, antioxidant capacity, pasting properties, etc.). Results obtained for particle size distribution and bulk density indicated that the particles increased and the color changed with the addition of cowpea flour. The raw tannin sorghum flour had a higher resistant starch concentration (36.3%) and antioxidant capacity (211.2 µmolTE/g), whereas cowpea flour had higher levels of proteins (18.7%) and dietary fiber (20.1%). This difference in the raw flour composition contributed to the nutritional value of the extrudates and cookies, especially the cookies which undergo dry heat and had higher retention of resistant starch and antioxidants. Moreover, sorghum flour presented a higher tendency to retrograde (high setback), which was decreased by the addition of cowpea flour. Overall acceptance and intention to purchase were higher for extrudates with 100% sorghum flour (6.52 and 68.3%, respectively) and cookies with 70% cowpea flour (7.03 and 76.7%, respectively). Therefore, nutritious and functional gluten-free extrudates and cookies, of good acceptability, can be produced from composite tannin sorghum and white cowpea flours.

Techno-Functional Properties of Corn Flour with Cowpea (Vigna unguilata) Powders Obtained by Extrusion.

Legumes are a good source of vegetal protein that improves diets worldwide. Cowpea has been used as fortification agents in some traditional corn foods in developing countries such as Colombia. The work aimed to evaluate the physicochemical properties of extruded mixtures of corn and cowpea flours to assess the use of these mixes as vegetable protein ingredients. Corn flour was mixed with 15, 30, and 50% of cowpea flour and extruded for this proposal. After extrusion, mixtures were ground to produce a powder. Techno-functional properties of powders as water content, hygroscopicity, water absorption, fat absorption, water solubility index, swelling index, bulk density, Hausner ratio, Carr index, and porosity were evaluated in the mixtures, extrudates, and obtained powders to assess the effect of the addition of cowpea on these properties. Results showed that processing powder obtained by extrusion and drying could be used as a powder to regenerate with water as a source of protein. Moreover, storing processing samples in sections (pellet format) is convenient to avoid wetting since this format is less hygroscopic and the same mass occupies less storage volume than powders.

Subcellular localization and interactions among TGB proteins of cowpea mild mottle virus.

Cowpea mild mottle virus (CPMMV) is a flexuous filamentous virus that belongs to the genus Carlavirus (family Betaflexiviridae). The CPMMV genome contains six open reading frames (ORFs), among which the triple gene block (TGB), encoded by ORFs 2 to 4, has been reported to encode movement proteins for different viruses. The subcellular localization of the TGB proteins of CPMMV isolate CPMMV:BR:MG:09:2 was analysed by transient expression of each protein fused to a fluorophore. Overall, the accumulation pattern and interactions among CPMMV TGB proteins (TGBp) were similar to those of their counterparts from the potex-like group. Considering these similarities, we evaluated the potential interactions between the TGB proteins of CPMMV and of potato virus X, which could complement cell-to-cell movement. The TGBp2 and TGBp3 of PVX had an effect on CPMMV TGBp1, directing it to the plasmodesmata, but the reverse was not true.

Baking Process Effects and Combined Cowpea Flour and Sorghum Bran on Functional Properties of Gluten-Free Cookies.

Gluten-related disorders, including celiac disease and non-celiac gluten sensitivity, are growing worldwide. The only treatment for both disorders is a lifelong gluten-free diet. However, gluten-free foods are generally poorer in nutrients, less healthy, and have a high cost. Sorghum and cowpea are gluten-free grains with high levels of phenolic compounds (PC) and a low cost. Their phenolic profile is structurally different; thus, the blend of both can provide synergistic/complementary health benefits to the final product. This study analyzed the effect of baking process and the blend of cowpea flour (CP) and sorghum bran (SB) on the levels of PC, resistant starch (RS), neutral detergent fiber (NDF), and antioxidant capacity (AC) of gluten-free cookies. Eleven rice or cowpea cookie formulations were made with or without white sorghum bran (WSB) or black sorghum bran (BSB). Baking increased the extractability of PC, AC, and the NDF of almost all formulations. The PC and AC were, respectively, about twice and 3-5 times higher in cookies containing BSB compared to the others. There was a minor effect of WSB on the PC and AC. Although there were losses, the retention of RS of cookies after the baking process was between 49.8 and 92.7%. Sorghum bran has excellent potential for use as a functional ingredient in healthy food production. The combined CP and SB have great potential to improve the nutritional and functional properties of gluten-free products, especially the PC, RS, and NDF contents.

A vicilin-like protein extracted from Clitoria fairchildiana cotyledons was toxic to Callosobruchus maculatus (Coleoptera: Chrysomelidae).

Callosobruchus maculatus is the main pest cowpea (Vigna unguiculata). Given its relevance as an insect pest, studies have focused in finding toxic compounds which could prevent its predatory action towards the seeds. Clitoria fairchildiana is a native Amazon species, whose seeds are refractory to insect predation. This characteristic was the basis of our interest in evaluating the toxicity of its seed proteins to C. maculatus larvae. Seed proteins were fractioned, according to their solubility, to albumins (F1), globulins (F2), kaphyrins (F3), glutelins (F4), linked kaphyrins (F5) and cross-linked glutelins (F6). The fractionated proteins were quantified, analysed by tricine-SDS-PAGE and inserted into the diet of this insect pest in order to evaluate their insecticidal potential. The most toxic fraction to C. maculatus, the propanol soluble F3, was submitted to molecular exclusion chromatography and all of the peaks obtained, F3P1, F3P2, F3P3, caused a reduction of larval mass, especially F3P1, seen as a major ~12 kDa electrophoretic band. This protein was identified as a vicilin-like protein by mass spectrometry and BLAST analysis. The alignment of the Cfvic (C. fairchildiana vicilin) peptides with a V. unguiculata vicilin sequence, revealed that Cfvic has at least five peptides (ALLTLVNPDGR, AILTLVNPDGR, NFLAGGKDNV, ISDINSAMDR, NFLAGEK) which lined up with two chitin binding sites (ChBS). This finding was corroborated by chitin affinity chromatography and molecular docking of chitin-binding domains for N-Acetyl-D-glucosamine and by the reduction of Cfvic chitin affinity after chemical modification of its Lys residues. In conclusion, Cfvic is a 12 kDa vicilin-like protein, highly toxic to C. maculatus, acting as an insect toxin through its ability to bind to chitin structures present in the insect midgut.

Deleterious effects of Schinus terebinthifolius Raddi seed flour on cowpea weevil, Callosobruchus maculatus (F.), larval development.

Schinus terebinthifolius, Raddi, has been extensively studied due to its anti-inflammatory and antibiotic properties. S. terebinthifolius was also toxic to some insects, however little has been explored about the nature of its insecticide compounds or the toxicity of this plant to insect species. In this work, we investigate the toxicity of S. terebinthifolius seed flour against the insect C. maculatus. S. terebinthifolius seed flour interfered with the post hatch development of the C. maculatus larvae, decreasing larval survival, mass and length. Using DEAE-cellulose chromatography, five protein fractions were isolated, a non-retained fraction (NRF) and four retained fractions, eluted with 0.25, 0.5, 0.7 and 1.0 M NaCl. Proteins with varying molecular masses were observed in all fractions. The majority protein bands were identified by mass spectrometry analysis and among the main identified proteins are 11S globulins (such glycinin), lipoxygenase, chitinases, 7S globulins (vicilins, canavalin and ß conglycinin), annexin, catalase and sucrose binding protein. All DEAE-protein fractions were toxic to the insect, interfering with the post hatch larval development and survival. Decreases greater than 90% were observed in the larval mass and length at 20 days after oviposition (DAO) for larvae raised on diet containing 0.5% of some fractions. Alterations in the level of proteins, glucose and in the activity of the enzymes lipases and cysteine proteases were also detected in these larvae. Our results show that seeds of S. terebinthifolius have an arsenal of toxic proteins with potential for the control of the insect C. maculatus.

IAF, QGF, and QDF Peptides Exhibit Cholesterol-Lowering Activity through a Statin-like HMG-CoA Reductase Regulation Mechanism: In Silico and In Vitro Approach.

In this study, in silico approaches are employed to investigate the binding mechanism of peptides derived from cowpea ß-vignin and HMG-CoA reductase. With the obtained information, we designed synthetic peptides to evaluate their in vitro enzyme inhibitory activity. In vitro, the total protein extract and <3 kDa fraction, at 5000 µg, support this hypothesis (95% and 90% inhibition of HMG-CoA reductase, respectively). Ile-Ala-Phe, Gln-Gly-Phe, and Gln-Asp-Phe peptides were predicted to bind to the substrate binding site of HMGCR via HMG-CoAR. In silico, it was established that the mechanism of HMG-CoA reductase inhibition largely entailed mimicking the interactions of the decalin ring of simvastatin and via H-bonding; in vitro studies corroborated the predictions, whereby the HMG-CoA reductase activity was decreased by 69%, 77%, and 78%, respectively. Our results suggest that Ile-Ala-Phe, Gln-Gly-Phe, and Gln-Asp-Phe peptides derived from cowpea ß-vignin have the potential to lower cholesterol synthesis through a statin-like regulation mechanism.

Technological potential of under-utilized starches from eight varieties of legumes grown in Cameroon / Potencial tecnológico de amidos subutilizados de oito variedades de leguminosas cultivadas nos Camarões

Starch samples from eight legumes cultivars instar of one variety of Vigna unguiculata L. (Cowpea), one variety of Vigna subterrenea V. (Bambara groundnut) and six varieties of Phaseolus vulgaris L. (Common bean), grown in Cameroon were isolated, and their physicochemical and pasting properties were evaluated. The objectives of the study were to investigate the starch properties and processing characteristics of different bean varieties, and to establish the basic foundation of improving the functionality of beans and their starch grown in the region. The result revealed significant differences amongst the properties of the starches. The swelling power of the legume starch isolates put them in the category of highly restricted-swelling starch. This characteristic is desirable for the manufacture of value-added products such as noodles and composite blends with cereals. The pasting properties were determined using a rapid visco analyzer, and various legumes bean starches exhibited different pasting profiles. The high breakdown viscosity (BV) was founded for Cowpea and Bambara groundnut and confirmed their low. ability to resist heat and shear stress when compared to Common bean varieties studies. The factors which influence the pasting characteristics resulting to decrease in peak viscosity (PV), trough viscosity (TV) and final viscosity (FV) of starch are attributed to the interaction of starch with the protein, fat, etc. which depended to their variety.(AU)

Foram isoladas amostras de amido de oito cultivares de leguminosas ínstar de uma variedade de Vigna unguiculata L. (feijão caupi), uma variedade de Vigna subterrenea V. (amendoim Bambara) e seis variedades de Phaseolus vulgaris L. (feijão comum), cultivadas nos Camarões, e suas propriedades físico-químicas e de pasta foram avaliadas. Os objetivos do estudo foram investigar as propriedades do amido e as características de processamento de diferentes variedades de feijão e estabelecer as bases básicas para melhorar a funcionalidade do feijão e do amido cultivado na região. O resultado revelou diferenças significativas entre as propriedades dos amidos. O poder de inchamento dos isolados de amido de leguminosas os coloca na categoria de amido com inchamento altamente restrito. Esta característica é desejável para o fabrico de produtos de valor acrescentado, tais como macarrão e misturas compósitas com cereais. As propriedades de pasta foram determinadas usando um analisador rápido de visco, e vários amidos de feijão leguminosos exibiram diferentes perfis de pasta. A alta BV foi fundada para o amendoim Cowpea e Bambara e confirmou sua baixa. capacidade de resistir ao calor e tensão de cisalhamento quando comparado com estudos de variedades de feijão. Os fatores que influenciam as características colantes resultantes da diminuição do pico de viscosidade (PV), da viscosidade mínima (TV) e da viscosidade final (FV) do amido são atribuídos à interação do amido com a proteína, gordura, etc., que dependem da sua variedade.(AU)

Technological potential of under-utilized starches from eight varieties of legumes grown in Cameroon / Potencial tecnológico de amidos subutilizados de oito variedades de leguminosas cultivadas nos Camarões

Abstract Starch samples from eight legumes cultivars instar of one variety of Vigna unguiculata L. (Cowpea), one variety of Vigna subterrenea V. (Bambara groundnut) and six varieties of Phaseolus vulgaris L. (Common bean), grown in Cameroon were isolated, and their physicochemical and pasting properties were evaluated. The objectives of the study were to investigate the starch properties and processing characteristics of different bean varieties, and to establish the basic foundation of improving the functionality of beans and their starch grown in the region. The result revealed significant differences amongst the properties of the starches. The swelling power of the legume starch isolates put them in the category of highly restricted-swelling starch. This characteristic is desirable for the manufacture of value-added products such as noodles and composite blends with cereals. The pasting properties were determined using a rapid visco analyzer, and various legumes bean starches exhibited different pasting profiles. The high breakdown viscosity (BV) was founded for Cowpea and Bambara groundnut and confirmed their low. ability to resist heat and shear stress when compared to Common bean varieties studies. The factors which influence the pasting characteristics resulting to decrease in peak viscosity (PV), trough viscosity (TV) and final viscosity (FV) of starch are attributed to the interaction of starch with the protein, fat, etc. which depended to their variety.

Resumo Foram isoladas amostras de amido de oito cultivares de leguminosas ínstar de uma variedade de Vigna unguiculata L. (feijão caupi), uma variedade de Vigna subterrenea V. (amendoim Bambara) e seis variedades de Phaseolus vulgaris L. (feijão comum), cultivadas nos Camarões, e suas propriedades físico-químicas e de pasta foram avaliadas. Os objetivos do estudo foram investigar as propriedades do amido e as características de processamento de diferentes variedades de feijão e estabelecer as bases básicas para melhorar a funcionalidade do feijão e do amido cultivado na região. O resultado revelou diferenças significativas entre as propriedades dos amidos. O poder de inchamento dos isolados de amido de leguminosas os coloca na categoria de amido com inchamento altamente restrito. Esta característica é desejável para o fabrico de produtos de valor acrescentado, tais como macarrão e misturas compósitas com cereais. As propriedades de pasta foram determinadas usando um analisador rápido de visco, e vários amidos de feijão leguminosos exibiram diferentes perfis de pasta. A alta BV foi fundada para o amendoim Cowpea e Bambara e confirmou sua baixa. capacidade de resistir ao calor e tensão de cisalhamento quando comparado com estudos de variedades de feijão. Os fatores que influenciam as características colantes resultantes da diminuição do pico de viscosidade (PV), da viscosidade mínima (TV) e da viscosidade final (FV) do amido são atribuídos à interação do amido com a proteína, gordura, etc., que dependem da sua variedade.

Exploring spatial dependence of cowpea-beans yield using global and local autocorrelation statistics in the Eastern Cariri region of Paraíba / Explorando a dependência espacial da produtividade do feijão-caupi usando estatísticas globais e locais de autocorrelação na região do Cariri oriental da Paraíba

This study evaluated the variability and characterizedthe spatial dependence between some soil attributes in the Eastern Cariri microregion of Paraíba, and analyzed the spatial correlations in order to identify the interactions between such attributes in cowpea bean (Vigna unguiculata L. Walp) production. Harvest data of the agricultural years of 2000-2017 in the Eastern Cariri microregion of Paraíba were analyzed. Parameters of the fitted models were estimated using the Maximum Likelihood method and the performance of the models was evaluated based on coefficients of determination (R²), maximum log-likelihood function, and Schwarzs Bayesian information criterion (BIC). Correlation and spatial autocorrelation between the cowpea productivity and agrometeorological elements was detected through the spatial analysis, using techniques such as the Morans index I. The study showed that, according to the performance indicators used, the spatial error model offered better results in relation to the classical multiple regression models and the self-regressive spatial models, indicating that the inclusion of spatial dependence in the models improves the estimate of productivity of cowpea in the microregion of Cariri Oriental da Paraíba.(AU)

O estudo tem por finalidade avaliar a variabilidade e caracterizar a dependência espacial entre alguns atributos dos solos na microrregião do Cariri Oriental da Paraíba, bem como estudar as correlações espaciais para identificar as interações entre tais atributos na produção do feijão-caupi. O estudo foi realizado com os dados das safras dos anos agrícolas de 2000-2017, da microrregião do Cariri Oriental da Paraíba. A estimativa de parâmetros dos modelos ajustados foi obtida utilizando o método de Máxima Verossimilhança e a avaliação do desempenho dos modelos foi realizada com base no coeficiente de determinação (R²), no máximo valor do logaritmo da função verossimilhança e no critério de informação bayesiano de Schwarz (BIC). Este estudo também permitiu verificar a correlação e autocorrelação espacial entre a produtividade do feijão e dos elementos agrometeorológicos, por meio da análise espacial, usando de técnicas como o índice I de Moran. O estudo mostrou que, de acordo com os indicadores de desempenho utilizados, o modelo de erro espacial ofereceu melhores resultados em relação aos modelos clássicos de regressão múltipla e aos modelos espaciais autorregressivos, indicando que a inclusão da dependência espacial nos modelos melhora a estimativa da produtividade do feijão-caupi em a microrregião do Cariri Oriental da Paraíba.(AU)

Exploring spatial dependence of cowpea-beans yield using global and local autocorrelation statistics in the Eastern Cariri region of Paraíba / Explorando a dependência espacial da produtividade do feijão-caupi usando estatísticas globais e locais de autocorrelação na região do Cariri oriental da Paraíba

ABSTRACT: This study evaluated the variability and characterizedthe spatial dependence between some soil attributes in the Eastern Cariri microregion of Paraíba,and analyzed the spatial correlations in order to identify the interactions between such attributes in cowpea bean(Vigna unguiculata L. Walp)production. Harvest data of the agricultural years of 2000-2017 in the Eastern Cariri microregion of Paraíba were analyzed. Parameters of the fitted models wereestimated using the Maximum Likelihood method and the performance of the models was evaluated based on coefficients of determination(R2), maximum log-likelihood function, and Schwarz's Bayesian information criterion (BIC). Correlation and spatial autocorrelation between the cowpea productivity and agrometeorological elements was detected through the spatial analysis, using techniques such as the Moran's index I. The study showed that, according to the performance indicators used, the spatial error model offered better results in relation to the classical multiple regression models and the self-regressive spatial models, indicating that the inclusion of spatial dependence in the models improves the estimate of productivity of cowpea in the microregion of Cariri Oriental da Paraíba.

RESUMO: O estudo tem por finalidade avaliar a variabilidade e caracterizar a dependência espacial entre alguns atributos dos solos na microrregião do Cariri Oriental da Paraíba, bem como estudar as correlações espaciais para identificar as interações entre tais atributos na produção do feijão-caupi. O estudo foi realizado com os dados das safras dos anos agrícolas de 2000-2017, da microrregião do Cariri Oriental da Paraíba. A estimativa de parâmetros dos modelos ajustados foi obtida utilizando o método de Máxima Verossimilhança e a avaliação do desempenho dos modelos foi realizada com base no coeficiente de determinação (R2), no máximo valor do logaritmo da função verossimilhança e no critério de informação bayesiano de Schwarz (BIC). Este estudo também permitiu verificar a correlação e autocorrelação espacial entre a produtividade do feijão e dos elementos agrometeorológicos, por meio da análise espacial, usando de técnicas como o índice I de Moran. O estudo mostrou que, de acordo com os indicadores de desempenho utilizados, o modelo de erro espacial ofereceu melhores resultados em relação aos modelos clássicos de regressão múltipla e aos modelos espaciais autorregressivos, indicando que a inclusão da dependência espacial nos modelos melhora a estimativa da produtividade do feijão-caupi em a microrregião do Cariri Oriental da Paraíba.

Exploring spatial dependence of cowpea-beans yield using global and local autocorrelation statistics in the Eastern Cariri region of Paraíba / Explorando a dependência espacial da produtividade do feijão-caupi usando estatísticas globais e locais de autocorrelação na região do Cariri oriental da Paraíba

This study evaluated the variability and characterizedthe spatial dependence between some soil attributes in the Eastern Cariri microregion of Paraíba, and analyzed the spatial correlations in order to identify the interactions between such attributes in cowpea bean (Vigna unguiculata L. Walp) production. Harvest data of the agricultural years of 2000-2017 in the Eastern Cariri microregion of Paraíba were analyzed. Parameters of the fitted models were estimated using the Maximum Likelihood method and the performance of the models was evaluated based on coefficients of determination (R²), maximum log-likelihood function, and Schwarz’s Bayesian information criterion (BIC). Correlation and spatial autocorrelation between the cowpea productivity and agrometeorological elements was detected through the spatial analysis, using techniques such as the Moran’s index I. The study showed that, according to the performance indicators used, the spatial error model offered better results in relation to the classical multiple regression models and the self-regressive spatial models, indicating that the inclusion of spatial dependence in the models improves the estimate of productivity of cowpea in the microregion of Cariri Oriental da Paraíba.

O estudo tem por finalidade avaliar a variabilidade e caracterizar a dependência espacial entre alguns atributos dos solos na microrregião do Cariri Oriental da Paraíba, bem como estudar as correlações espaciais para identificar as interações entre tais atributos na produção do feijão-caupi. O estudo foi realizado com os dados das safras dos anos agrícolas de 2000-2017, da microrregião do Cariri Oriental da Paraíba. A estimativa de parâmetros dos modelos ajustados foi obtida utilizando o método de Máxima Verossimilhança e a avaliação do desempenho dos modelos foi realizada com base no coeficiente de determinação (R²), no máximo valor do logaritmo da função verossimilhança e no critério de informação bayesiano de Schwarz (BIC). Este estudo também permitiu verificar a correlação e autocorrelação espacial entre a produtividade do feijão e dos elementos agrometeorológicos, por meio da análise espacial, usando de técnicas como o índice I de Moran. O estudo mostrou que, de acordo com os indicadores de desempenho utilizados, o modelo de erro espacial ofereceu melhores resultados em relação aos modelos clássicos de regressão múltipla e aos modelos espaciais autorregressivos, indicando que a inclusão da dependência espacial nos modelos melhora a estimativa da produtividade do feijão-caupi em a microrregião do Cariri Oriental da Paraíba.

Identification, characterization, and expression analysis of cowpea (Vigna unguiculata [L.] Walp.) miRNAs in response to cowpea severe mosaic virus (CPSMV) challenge.

KEY MESSAGE: Cowpea miRNAs and Argonaute genes showed differential expression patterns in response to CPSMV challenge Several biotic stresses affect cowpea production and yield. CPSMV stands out for causing severe negative impacts on cowpea. Plants have two main induced immune systems. In the basal system (PTI, PAMP-triggered immunity), plants recognize and respond to conserved molecular patterns associated with pathogens (PAMPs). The second type (ETI, Effector-triggered immunity) is induced after plant recognition of specific factors from pathogens. RNA silencing is another important defense mechanism in plants. Our research group has been using biochemical and proteomic approaches to learn which proteins and pathways are involved and could explain why some cowpea genotypes are resistant whereas others are susceptible to CPSMV. This current study was conducted to determine the role of cowpea miRNA in the interaction between a resistant cowpea genotype (BRS-Marataoã) and CPSMV. Previously identified and deposited plant microRNA sequences were used to find out all possible microRNAs in the cowpea genome. This search detected 617 mature microRNAs, which were distributed in 89 microRNA families. Next, 4 out of these 617 miRNAs and their possible target genes that encode the proteins Kat-p80, DEAD-Box, GST, and SPB9, all involved in the defense response of cowpea to CPSMV, had their expression compared between cowpea leaves uninoculated and inoculated with CPSMV. Additionally, the differential expression of genes that encode the Argonaute (AGO) proteins 1, 2, 4, 6, and 10 is reported. In summary, the studied miRNAs and AGO 2 and AGO4 associated genes showed differential expression patterns in response to CPSMV challenge, which indicate their role in cowpea defense.

Efficacy of bioactive compounds and their association with different cowpea cultivars against their major stored pest.

BACKGROUND: Stored grain insects are controlled with fumigant insecticides which can select resistant insect populations and cause environmental and applicator contamination. Thus, resistant cultivars and chemical constituents of essential oils are an alternative to the almost exclusive use of these insecticides. The effects of the combination of cowpea cultivars Vigna unguiculata (L.) Walp. with chemical constituents of essential oils against Callosobruchus maculatus were determined. Four cowpea cultivars: BRS Tracuateua, BR 17 Gurgueia, Epace 10 and Sempre Verde (insect rearing) untreated were used in the experiments and combined with chemical constituents of essential oil: eugenol, geraniol and trans-anethole. The biological parameters observed were: total egg number and eggs per grain, egg viability (%), insects emerged and insects per grain, immature stage viability (%), instantaneous rate of growth (ri), insect dry weight (mg), grain weight loss (%) and egg-adult period. RESULTS: When comparing all biological parameters, the cultivars BRS Tracuateua and BR 17 Gurgueia were harmful to C. maculatus. In the toxicity tests, the results showed that LC30 and LC50 of the chemical constituents ranged from 54.77 to 103.48 ppm and 60.99 to 125.18 ppm, respectively. In most of the biological parameters, LC50 had adverse effects significantly higher than LC30 and BR 17 Gurgueia treated were harmful to C. maculatus. CONCLUSIONS: Overall, the findings showed that BR 17 Gurgueia combined with eugenol and geraniol more significantly affected the biological parameters of C. maculatus than when associated with trans-anethole, reducing egg number, insects emerged and egg viability. © 2020 Society of Chemical Industry.

Inhibition mechanism of human salivary α-amylase by lipid transfer protein from Vigna unguiculata.

VuLTP1.1, a LTP1 from Vigna unguiculata, inhibits 78.1 % of the human salivary α-amylase (HSA) activity at 20 µM. We had performed a correlation study between VuLTP1.1 structure and HSA inhibitory activity and showed that two VuLTP1.1 regions are responsible for HSA inhibition. In one of them we had characterized the crucial importance of an Arg39 for inhibition. In this work, we analyzed the VuLTP1.1-HSA interaction by protein-protein docking to understand the most probable interaction model and the mechanism of HSA inhibition by VuLTP1.1. The VuLTP1.1 tertiary structure quality and refinement as well as the docking assay between VuLTP1.1 and HSA were done by bioinformatic programs. HSA inhibition occurs by direct interaction of the VuLTP1.1 with the HSA causing the obstruction of the carbohydrate biding cleft with Gibbs free energy of -18.5 Kcal/mol and the dissociation constant of 2.6E-14 M. The previously identified Arg39 of VuLTP1.1 is burrowed into the active site of the HSA and there it interacts with the Asp300 of HSA catalytic site by a hydrogen bond. We had confirmed the importance of the Arg39 of VuLTP1.1 for the HSA inhibition which interacts with the Asp300 at the HSA active site. I-2, a LTP-like peptide, presents the same HSA inhibition pattern that VuLTP1.1, which indicates that the inhibition mechanism of the LTPs towards α-amylase is very similar. For the best of our knowledge, it is the first time that the HSA inhibition mechanism was understood and described for the LTP1s using VuLTP1.1 and I-2 as prototype inhibitors.

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.

Toxicity of the essential oil of basil cultivars and hybrids and its repellent effect on stored grain pests / Toxicidade do óleo essencial de cultivares e híbridos de manjericão e seu efeito repelente sobre pragas de grãos armazenados

Essential oils have emerged as an alternative to synthetic insecticides in the control of stored grain pests. The toxicity and repellency of the essential oils of four basil cultivars and three basil hybrids and the monoterpenes linalool, citral, and (E)-methyl cinnamate were evaluated in the stored grain pests Callosobruchus maculatus and Sitophillus zeamais. The essential oils of the cultivar Genovese and the hybrid 'Genovese' x 'Maria Bonita' were more toxic to C. maculatus. Conversely, the essential oils of the cultivar Sweet Dani and the hybrid 'Cinnamom' x 'Maria Bonita' were more toxic to S. zeamais. Among the monoterpenes, (E)-methyl cinnamate was the most toxic to both pests, taking 0.14 and 0.34 µ L.mL-1 to kill 50% of the C. maculatus and S. zeamais populations, respectively. All essential oils from cultivars, hybrids, and monoterpenes were repellent to S. zeamais, except for (E)-methyl cinnamate. For C. maculatus, this effect was lower, being citral the most repellent compound. Results demonstrate the insecticidal potential of the essential oil of O. basilicum and its monoterpenes in the control of stored grain pests.

Os óleos essenciais surgem como alternativa aos inseticidas sintéticos no controle das pragas de grãos armazenados. A toxicidade e a repelência dos óleos essenciais de quatro cultivares e três híbridos de manjericão e dos monoterpenos linalol, citral e (E)-cinamato de metila foram avaliadas nas pragas de grãos armazenados Callosobruchus maculatus e Sitophillus zeamais. Os óleos essenciais da cultivar Genovese e do híbrido 'Genovese' x 'Maria Bonita' foram mais tóxicos para C. maculatus. Já para S. zeamais, os óleos essenciais das cultivar Sweet Dani e do híbrido 'Cinnamom' x 'Maria Bonita' apresentaram maior toxicidade. Dentre os monoterpenos, o (E)-cinamato de metila foi o mais tóxico para ambas as pragas. Foram necessários 0,14 e 0,34 µ L.mL-1 para matar 50% da população de C. maculatus e S. zeamais. Todos os óleos essenciais das cultivares, dos híbridos e dos monoterpenos foram repelentes a S. zeamais, com exceção do (E)-cinamato de metila. Já para C. maculatus, este efeito foi reduzido, sendo o citral o composto mais repelente. Nos resultados demonstram o potencial inseticida dos óleos essenciais de O. basilicum e seus monoterpenos para o controle de pragas de grãos armazenados.

Population parameters as a way to evaluate the risk of attack of Aphis craccivora (Hemiptera: Aphididae) on cowpea / Parâmetros populacionais como forma de avaliar os riscos de ataque de Aphis craccivora (Hemiptera: Aphididae) em feijão-caupi

The objective of this research was to develop fertility life tables in order to estimate the population parameters of black aphid (Aphis craccivora Koch) in cowpea (Vigna unguiculata) varieties, aiming to propose a risk scale for its use. The experiment consisted of six treatments and six replicates (five varieties plus the cultivar VITA 7 as a susceptible control). A cohort was formed with six adult females distributed in six replicates of each genotype, and the insects were observed daily. Based on the data, fertility life tables were drawn for each variety and the population parameters were estimated. The different values of the finite growth rate (λ) were considered to propose a risk scale for the use of the genotypes. The results obtained give the dimension of the variability of V. unguiculata in respect to the character, resistance to A. craccivora, with antibiosis as the main mechanism of resistance. Considering all the results, the varieties studied can be classified according to their suitability as a plant favorable to the development of the black aphid as follows: VITA 7 > CE-13 > CE-51 > CE-08 = CE-07. The proposal of a risk scale for the use of V. unguiculata genotypes against the A. craccivora population, based on the finite growth rate (λ) values, was adequate to discriminate the varieties studied.(AU)

Objetivou-se nesta pesquisa elaborar tabelas de vida de fertilidade com o intuito de estimar os parâmetros populacionais de pulgão-preto (Aphis craccivora Koch) em variedades de feijão-caupi (Vigna unguiculata), visando propor uma escala de risco para o seu uso. O experimento constituiu-se em seis tratamentos (cinco variedades mais o cultivar VITA 7 como padrão de suscetibilidade) com seis repetições. Formou-se uma coorte com seis fêmeas adultas distribuídas em cada genótipo, sendo todos os indivíduos observados diariamente. De posse dos dados, foram elaboradas tabelas de vida de fertilidade para cada variedade e estimados os parâmetros populacionais. Para propor uma escala de risco de uso de genótipos, ponderou-se sob os diferentes valores da razão finita de crescimento (λ). Os resultados obtidos dão a dimensão da variabilidade de V. unguiculata com relação ao caráter da resistência a A. craccivora, sendo a antibiose o principal mecanismo de resistência associado. Considerando-se todos os resultados, foi possível hierarquizar as variedades estudadas segundo sua aptidão como planta favorável ao desenvolvimento ao pulgão-preto conforme segue: VITA 7 >> CE-13 > CE-51 > CE-08 = CE-07. A proposta de uma escala de risco do uso de genótipos de V. unguiculata frente à população de A. craccivora, baseada nos valores da razão finita de crescimento (λ), foi adequada para discriminar as variedades estudadas.(AU)