Application of a Combined Peptidomics and In Silico Approach for the Identification of Novel Dipeptidyl Peptidase-IV-Inhibitory Peptides in In Vitro Digested Pinto Bean Protein Extract

The conventional approach in bioactive peptides discovery, which includes extensive bioassay-guided fractionation and purification processes, is tedious, time-consuming and not always successful. The recently developed bioinformatics-driven in silico approach is rapid and cost-effective; however, it lacks an actual physiological significance. In this study a new integrated peptidomics and in silico method, which combines the advantages of the conventional and in silico approaches by using the pool of peptides identified in a food hydrolysate as the starting point for subsequent application of selected bioinformatics tools, has been developed. Pinto bean protein extract was in vitro digested and peptides were identified by peptidomics. The pool of obtained peptides was screened by in silico analysis and structure–activity relationship modelling. Three peptides (SIPR, SAPI and FVPH) were selected as potential inhibitors of the dipeptidyl-peptidase-IV (DPP-IV) enzyme by this integrated approach. In vitro bioactivity assay showed that all three peptides were able to inhibit DPP-IV with the tetra-peptide SAPI showing the highest activity (IC50 = 57.7 μmol/L). Indeed, a new possible characteristic of peptides (i.e., the presence of an S residue at the N-terminus) able to inhibit DPP-IV was proposed.

The Microbiota of a Mite Prey-predator System on Different Host Plants Are Characterized by Functional Redundancy and Dysbiosis

Microbiota have diverse roles in the life cycles of their hosts, affecting their growth, development, behavior, and reproduction. Changes in physiological conditions of the host can also impact the assemblage of host-associated microorganisms. However, little is known of the effects of host plant–prey–predatory mite interactions on mite microbiota. We compared the microbial communities of eggs and adult females of the two˗spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) and of adult females of the predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) on four different host plants (cotton, maize, pinto bean, and tomato) by metabarcoding sequencing of the V3–V4 region of the 16S ribosomal RNA gene (16S rRNA), using the Illumina MiSeq platform. Only the egg microbiota of T. urticae was affected by the host plant. The microbiota of the predatory mite N. californicus was very different from that of its prey, and the predator microbiota was unaffected by the different host plant–prey systems tested. Only the microbiota of the eggs of T. urticae carried Serratia as a high fidelity-biomarker. Biomarker bacteria were also detected in the microbiota of adult females of T. urticae and N. californicus, with different biomarkers in each host-plant species. The microbiota associated with eggs and adult females of T. urticae and adult females of N. californicus differed in their potential contributions to the host mite.

Evaluation of Physical, Mechanical and Antibacterial Properties of Pinto Bean Starch-Polyvinyl Alcohol Biodegradable Films Reinforced with Cinnamon Essential Oil

In the present study, various blended films from polyvinyl alcohol (PVA) and pinto bean starch (PBS) were prepared and the selected film was used to fabricate an antimicrobial packaging film. Different essential oils (EOs) were also exposed to minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests to find the most efficient EO against a range of microorganisms. From the primary studies, the PVA:PBS (80:20) and cinnamon essential oil (CEO) were chosen. Afterward, the blend composite film reinforced by 1, 2, and 3% CEO and several, physical, mechanical, structural, and antimicrobial attributes were scrutinized. The results showed a significant modification of the barrier and mechanical properties of the selected blended films as a result of CEO addition. Scanning electron micrographs confirmed the incorporation and distribution of CEO within the film matrix. The X-ray diffraction (XRD) patterns and Fourier transform infrared (FTIR) spectra indicated the interaction of CEO and the PVA-PBS composite. The antibacterial of the tested bacteria showed a significant increase by increasing the CEO concentration within the control film. CEO-loaded films were more effective in controlling Gram-positive bacteria compared to Gram-negative bacteria. It can be concluded that PVA-PBS-CEO films are promising candidates to produce biodegradable functional films for food and biomedical applications.

Cell Wall Permeability of Pinto Bean Cotyledon Cells Regulates In Vitro Fecal Fermentation and Gut Microbiota

Processing induced structural changes of whole foods on regulation of colonic fermentation rate and microbiota composition are least understood and often overlooked. In the present study, intact cotyledon cells from...

Acute effects of extruded pulse snacks on glycemic response, insulin, appetite, and food intake in healthy young adults in a double blind, randomized crossover trial

Research indicates that the post-prandial glycemic benefits of consuming whole pulses are retained when consumed in a mixed meal, pureed, and ground into flours. The glycemic benefits of pulse flours when incorporated into extruded products are unknown. In a randomized, repeated-measures crossover study, adults (n = 26) consumed extruded corn snacks made with the addition of 40% pulse flour from either: whole yellow pea, split yellow pea, green lentil, chickpea, or pinto bean. The control snack was 100% corn. Food intake was measured with an ad libitum meal consumed at 120 min. Blood glucose (BG), insulin and appetite were measured regularly before (pre-meal, 0-120 min) and after (post-meal, 140-200 min) the meal. Pinto bean and chickpea snacks led to lower (p<0.05) pre-meal BG incremental area under the curve (iAUC), compared with control, whole yellow pea and green lentil snacks. Pinto bean snack also led to lower (pre-meal BG (p<0.05) and insulin (p<0.05) iAUC compared with control, whole yellow pea, and split yellow pea snacks. There were no differences in food intake or appetite. These findings indicate that effects of replacing corn with pulse flours in extruded snacks on BG, and insulin are dependent on pulse type. ClinicalTrials.gov Identifier: NCT02402504. Registered on 30 March 2015. Novelty bullets: The incorporation of pinto bean and chickpea flour into extruded corn snacks improves postprandial glycemic response. Pulse containing snacks were equally as palatable as the corn snacks. The incorporation of pulses into corn snacks increased the protein and fibre content.

Pinto Bean Response to Seeding Rate and Herbicides

Field experiments were conducted in 2016 and 2017 to evaluate the effects of seeding rate and herbicide programs on weed control and pinto bean yield under irrigation. The experiments were 5 by 5 factorial randomized complete block design with five replications. The weed control treatments comprised a non-treated control, hand-weeded control, EPTC + ethalfluralin PRE, EPTC + ethalfluralin PRE followed by (fb) dimethenamid-P POST at V1, and EPTC + ethalfluralin PRE fb bentazon/imazamox POST. There were five seeding rates ranging from 247000 to 494000 seeds ha-1 planted in 19-cm rows. Weed biomass was reduced by 6 kg ha-1 with every additional 1000 seeds ha-1. EPTC plus ethalfluralin fb either dimethenamid-P or bentazon plus imazamox reduced weed biomass by at least 29% compared to the nontreated control. There was a significant effect of weed control treatment on pinto bean yield (P=0.0004). However, there was no significant seeding rate (P=0.42) or seeding rate by weed control interaction effect on pinto bean yield (P=0.38). Pinto bean yield ranged from 3.08 Mg ha-1 in the nontreated control to 4.74 Mg ha-1 hand-weeded treatment. Increased seeding rate in narrow rows is a cultural practice that can improve weed control in pinto bean but may not necessarily increase yield.

Population Density and Damage Caused by Two Spotted Spider Mite, Tetranychus urticae Koch on Different Pinto Bean Lines Under Field Conditions

In this study, population density and yield loss caused by two-spotted spider mite (TSSM) on eight lines of pinto bean were studied under field conditions during two successive years (2009-2010). The experiment was arranged in completely randomized block design with subdivided plots and four replications in Lordegan fields, Chaharmahal va Bakhtiari province, Iran. The main plots and sub-plots consisted of bean lines and acaricides application, respectively. Population density of TSSM was recorded at weekly intervals, beginning from the seedling stage and continued to harvesting time on different lines. Yield loss caused by the mite on each line, was calculated by subtracting the average yields in sprayed subplots versus unsprayed subplots. For this purpose, 10 plants from each subplot were selected randomly and the yield and yield components including; the number of pods/plant, number of seeds/pod and weight of 100 seeds were recorded. Moreover, the grain yield (kg. ha-1) was determined by harvesting the central area (10 m2) in each subplot. Our results indicated significant differences in TSSM population (eggs, juveniles and adults) among the studied lines. In 2009, the highest number of mite was recorded on line ‘L29’ (120.20 ± 18.79) whereas, the lowest on line ‘L1’ (22.51 ± 4.96 mites/ 2 cm2 of the abaxial leaf surface). Moreover, during 2010, the highest and the lowest population density of the mite were supported by line ‘D3’ (55.53 ± 5.68) and line ‘L1’ (9.33 ± 0.79 mites/ 2 cm2 of the abaxial leaf surface), respectively. Mean yield loss of pinto bean lines due to the mite attack calculated 1460.6 kg. ha-1 (64.1 ± 10.2%) and 1278.7 kg. ha-1 (61.4 ± 8.6%) in 2009 and 2010, respectively. The highest grain yield loss presented by line ‘L1’ (91.1 ± 12.1% and 86.4 ± 8.9%) followed by lines ‘L29’and ‘L30’, whereas, the lowest observed in lines ‘J29’ (41.5 ± 7.7% and 37.5 ± 7.6%) and ‘L19’ (50.7 ± 6.6% and 47.4 ± 5.4% in 2009 and 2010, respectively).