A Multi-Year, Multi-Cultivar Approach to Differential Expression Analysis of High- and Low-Protein Soybean (Glycine max).

Soybean (Glycine max (L.) Merr.) is among the most valuable crops based on its nutritious seed protein and oil. Protein quality, evaluated as the ratio of glycinin (11S) to ß-conglycinin (7S), can play a role in food and feed quality. To help uncover the underlying differences between high and low protein soybean varieties, we performed differential expression analysis on high and low total protein soybean varieties and high and low 11S soybean varieties grown in four locations across Eastern and Western Canada over three years (2018-2020). Simultaneously, ten individual differential expression datasets for high vs. low total protein soybeans and ten individual differential expression datasets for high vs. low 11S soybeans were assessed, for a total of 20 datasets. The top 15 most upregulated and the 15 most downregulated genes were extracted from each differential expression dataset and cross-examination was conducted to create shortlists of the most consistently differentially expressed genes. Shortlisted genes were assessed for gene ontology to gain a global appreciation of the commonly differentially expressed genes. Genes with roles in the lipid metabolic pathway and carbohydrate metabolic pathway were differentially expressed in high total protein and high 11S soybeans in comparison to their low total protein and low 11S counterparts. Expression differences were consistent between East and West locations with the exception of one, Glyma.03G054100. These data are important for uncovering the genes and biological pathways responsible for the difference in seed protein between high and low total protein or 11S cultivars.

Phenazines are involved in the antagonism of a novel subspecies of Pseudomonas chlororaphis strain S1Bt23 against Pythium ultimum.

Long-term use of chemical fungicides to control plant diseases caused by fungi and oomycetes has led to pathogen resistance and negative impacts on public health and environment. There is a global search for eco-friendly methods and antagonistic bacteria are emerging as alternatives. We isolated a potent antagonistic bacterial strain (S1Bt23) from woodland soil in Québec, Canada. Taxonomic characterization by 16S rRNA, multi-locus sequence analysis, pairwise whole-genome comparisons, phylogenomics and phenotypic data identified strain S1Bt23 as a novel subspecies within Pseudomonas chlororaphis. In dual culture studies, strain S1Bt23 exhibited potent mycelial growth inhibition (60.2-66.7%) against Pythium ultimum. Furthermore, strain S1Bt23 was able to significantly bioprotect potato tuber slices from the development of necrosis inducible by P. ultimum. Annotations of the whole genome sequence of S1Bt23 revealed the presence of an arsenal of secondary metabolites including the complete phenazine biosynthetic cluster (phzABCDEFG). Thin-layer (TLC) and high-performance liquid (HPLC) chromatographic analyses of S1Bt23 extracts confirmed the production of phenazines, potent antifungal compounds. CRISPR/Cas9-mediated deletion of phzB (S1Bt23ΔphzB) or phzF (S1Bt23ΔphzF) gene abrogated phenazine production based on TLC and HPLC analyses. Also, S1Bt23ΔphzB and S1Bt23ΔphzF mutants lost antagonistic activity and bioprotection ability of potato tubers against P. ultimum. This demonstrated that phenazines are involved in the antagonistic activity of S1Bt23 against P. ultimum. Finally, based on genotypic and phenotypic data, we taxonomically conclude that S1Bt23 represents a novel subspecies for which the name Pseudomonas chlororaphis subsp. phenazini is proposed.

Sensorial, textural, and rheological analysis of novel pistachio-based chocolate formulations by quantitative descriptive analysis.

Principal component analysis (PCA) was used to investigate the effects of pistachio oil (7.5 and 15%), xanthan gum (0 and 0.3%), distillated monoglyceride (0.5 and 1%), and cocoa butter (7.5 and 15%) on the sensorial descriptors of spread based on pistachio oil. The response variables were the most significant spread texture attributes: hardness, graininess, meltability, adhesiveness to spoon, adhesiveness to mouth, spreadability, fluidity, and oiliness. PCA revealed that the first two principal components explained 90% or more of the variance between the data. The first principal component was dominated by the descriptors' adhesiveness and hardness on the positive side and the descriptors' oiliness and fluidness on the negative side. The descriptor spreadability had a high positive loading on the second principal component. Herschel-Balkley and power law models were fitted to confirm the sensory evaluation results on different formulations. In the current research, the power law model seemed to be more accurate for fitting the samples. In terms of the selected texture attributes determined by the sensory evaluation, using component plot, the optimum combination of variables was found as follows: 15 pistachio oil, 7.5% cocoa butter, 0.3% xanthan gum, and 1% distilled monoglyceride that produced desirable spreads that mimic commercial spread.

Differential gene expression provides leads to environmentally regulated soybean seed protein content.

Soybean is an important global source of plant-based protein. A persistent trend has been observed over the past two decades that soybeans grown in western Canada have lower seed protein content than soybeans grown in eastern Canada. In this study, 10 soybean genotypes ranging in average seed protein content were grown in an eastern location (control) and three western locations (experimental) in Canada. Seed protein and oil contents were measured for all lines in each location. RNA-sequencing and differential gene expression analysis were used to identify differentially expressed genes that may account for relatively low protein content in western-grown soybeans. Differentially expressed genes were enriched for ontologies and pathways that included amino acid biosynthesis, circadian rhythm, starch metabolism, and lipid biosynthesis. Gene ontology, pathway mapping, and quantitative trait locus (QTL) mapping collectively provide a close inspection of mechanisms influencing nitrogen assimilation and amino acid biosynthesis between soybeans grown in the East and West. It was found that western-grown soybeans had persistent upregulation of asparaginase (an asparagine hydrolase) and persistent downregulation of asparagine synthetase across 30 individual differential expression datasets. This specific difference in asparagine metabolism between growing environments is almost certainly related to the observed differences in seed protein content because of the positive correlation between seed protein content at maturity and free asparagine in the developing seed. These results provided pointed information on seed protein-related genes influenced by environment. This information is valuable for breeding programs and genetic engineering of geographically optimized soybeans.

Phenolic profile and antioxidant activity from non-toxic Mexican Jatropha curcas L. shell methanolic extracts.

Jatropha curcas seed shells are the by-product obtained during oil extraction process. Recently, its chemical composition has gained attention since its potential applications. The aim of this study was to identify phenolic compounds profile from a non-toxic J. curcas shell from Mexico, besides, evaluate J. curcas shell methanolic extract (JcSME) antioxidant activity. Free, conjugate and bound phenolics were fractionated and quantified (606.7, 193.32 and 909.59 µg/g shell, respectively) and 13 individual phenolic compounds were detected by HPLC. The radical-scavenging activity of JcSME was similar to Trolox and ascorbic acid by DPPH assay while by ABTS assay it was similar to BHT. Effective antioxidant capacity by ORAC was found (426.44 ± 53.39 µmol Trolox equivalents/g shell). The Mexican non-toxic J. curcas shell is rich in phenolic compounds with high antioxidant activity; hence, it could be considerate as a good source of natural antioxidants.

Effect of glycerol concentration on edible film production from cress seed carbohydrate gum.

In this study an edible film plasticized with glycerol was successfully prepared from cress seed gum (CSG). The physical, optical, water vapor permeability (WVP) and mechanical properties of CSG films incorporated with three levels of glycerol (25%, 35%, and 50% w/w) as plasticizer were determined. Dynamic mechanical thermal analysis was used to determine the glass transition temperature. WVP of the films was found to increase as the glycerol content increased from 25% to 50% w/w in the formulation, resulted in improvement of films flexibility and significantly lower tensile strength and higher elongation at break. The color measurement values showed that increasing the glycerol concentration in polymer matrix caused the b and L values increased while ΔE value decreased. The electron scanning micrograph indicated smooth and uniform surface morphology without signs of phase separation between the film components. The results of the present study demonstrated that CSG can promisingly be used in producing edible films with improved quality characteristics.

Stability and dynamic rheological characterization of spread developed based on pistachio oil.

This study investigated the influence of formulation variables (pistachio oil (PO, 7.5 and 15%, w/w), Cocoa butter (CB, 7.5 and 15%, w/w), xanthan gum (XG, 0 and 0.3%, w/w), and distillated monoglyceride (DMG, 0.5 and 1%, w/w)) on the rheological properties and emulsion stability of spreads. Power law and Herschel-Bulkley models were used for modeling shear-thinning behavior of samples. The power law model was found to describe the flow behavior of spreads better than Herschel-Bulkley model. All the rheological properties were increased by adding XG to the spreads whereas increasing PO content caused to decrease them. The DMG had positive effect on apparent viscosity and elastic behavior but had negative effect on viscose behavior. Apparent viscosity was increased by adding CB while rheological modules were not significantly (p < 0.05) affected. The XG and DMG improved stability of emulsion. The best spread formulation with optimum rheological properties was 15% PO, 7.5% CB, 0.3% XG and 1% DMG.