Genetic Analysis and Molecular Identification of Virulence in Xanthomonas oryzaepv.oryzaeIsolates

Bacterial leaf blight (BLB) of rice is a very destructive disease worldwide and is caused byXanthomonas oryzaepv.oryzae(Xoo).The aimofthepresentstudywastoexamineiftheXoovirulence pathotypes obtained using phenotypic pathotyping could be confirmed using molecular approach. After screening of 60 Operon primers with genomic DNA of twoXooisolates (virulent pathotype,Vr, and mildly virulent pathotype,MVr), 12 Operon primers that gave reproducible and useful genetic information were selected and used to analyze 50Xooisolates from 7 West African countries. Genetic analysis revealed two majorXoovirulence genotypes (Mta andMtb)withMtahaving two subgroups (Mta1andMta2).Mta1(Vr1) subgroup genotype has occurrence in six countries and Mta2(Vr2) in three countries whileMtbgenotype characterized mildly virulence (MVr)Xooisolates present in five countries. The study revealed possible linkage and correlation between phenotypic pathotyping and molecular typing ofXoovirulence.Xoo virulence genotypes were known to exist within country and there was evidence ofXoopathogen migration between countries. Durable resistance rice cultivars would need to overcome bothMtaandMtb Xoovirulence genotypes in order to survive after their deployment into different rice ecologies in West Africa

Two genotypes of Xanthomonas oryzae pv. oryzae virulence identified in West Africa

Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo), is a very destructive rice disease worldwide. The aim of the present study was to examine if the Xoo virulence pathotypes obtained using phenotypic pathotyping could be confirmed using molecular approach. After screening of 60 Operon primers with genomic DNA of two Xoo isolates (virulent pathotype, Vr and mildly virulent pathotype, MVr), 12 Operon primers that gave reproducible and useful genetic information were selected and used to analyze 50 Xoo isolates from 7 West African countries. Genetic analysis revealed two major Xoo virulence molecular type (Mt) which were Mta and Mtb with Mta having two subgroups (Mta1 and Mta2). Mta1 (Vr1) subgroup genotype has occurrence in six countries and Mta2 (Vr2) in three countries while Mtb genotype characterized mildly virulence (MVr) Xoo isolates present in five countries. The study revealed possible linkage and correlation between phenotypic pathotyping and molecular typing of Xoo virulence. Durable resistance rice cultivars would need to overcome both Mta and Mtb Xoo virulence genotypes in order to survive after their deployment into different rice ecologies in West Africa

Genetic Analysis of Effect of Heat Stress on Genomic DNA from Cowpea ( Vigna unguiculata (L) Walp.)

Aims: Genetic analysis was used to study the effect of heat st ress on young seedlings of cowpea ( Vigna unguiculata (L) Walp.). Study Design: Four different colors of cowpea seeds (white, dirty w hite, deep brown and light brown) were obtained from GeneBank of International Institute of Tropical Agriculture (IITA) Ibadan, Nigeria. Seeds from each of the cowpea four colors we re first pre-germinated and young seedlings subjected to DNA extraction. Extracted DNA subjected to different temperature treatments at 75°C and 100°C for one hour and control not heated. Place and Duration of Study: Department of Chemical Sciences Afe Babalola University Ado Ekiti, Nigeria between January 2015 and June 2015. Methodology: UV wavelength absorption spectrum analysis (A 200 – A 960 ) was carried out on control DNA and DNA heated at 75°C and 100°C respectively. Cl uster analysis of optical density (OD) data was carried out to establish the relationship between co ntrol DNA and heat treated DNA (75°C and 100°C). Results: DNA concentrations of Vigna unguiculata (L) Walp. were between 0.40 to 1.15 mg/ml, 0.33 to 0.84 mg/ml, and 0.26 to 0.89 mg/ml for control a nd heat treatments of 75°C and 100°C respectively. DNA UV absorption spectra of control and heat treatments of 75°C and 100°C were generally different due to differential UV wavelengt h absorption. Cluster analysis revealed three different clusters (cluster 1, cluster 2 and cluster 3) among control DNA and heat treated DNA. Cluster 1 comprised of V1-control, V1-75°C and V1-10 0°C, with V1-75°C and V1-100°C having similar characters. Cluster 2 was made up of V4-control, V4-75°C and V4-100°C, with V4-75°C and V4-100°C having the same characters. Cluster 3 was largel y characterized by dissimilar DNA extracts of V3-75°C, V2-control, V3-100°C, V2-100°C, V 3-control and V2-75°C. Conclusion: Genetic diversity among individual Vigna unguiculata (L) Walp. accession DNA as obtained in this study could possibly be as a result of variations in heat tolerance among dissimilar cowpea genomic composition

Antidiabetic potential of methanolic and flavonoid-rich leaf extracts of Synsepalum dulcificum in type 2 diabetic rats

Background: Synsepalum dulcificum is a plant indigenous to West Africa. The fruit is used to modify taste of foods to sweetness. Objectives: This study aims to investigate the antidiabetic potentials of both methanolic and flavonoid-rich leaf extracts of S. dulcificum (MSD and FSD respectively) in type 2 diabetic Wistar albino rats. Materials and methods: Sixty three rats were randomly distributed into nine groups of seven animals each with group 1 serving as the normal control. Groups 2 to 7 were given 10% fructose in their drinking water for 14 days, after which 40 mg/kg of streptozotocin was administered. Group 2 animals served as the diabetic control, while groups 3, 4, 5, 6 and 7 were treated with 30 mg/kg MSD, 60 mg/kg MSD, 30 mg/kg FSD, 60 mg/kg FSD and 5 mg/kg glibenclamide respectively. Groups 8 and 9, contained healthy animals, and were treated with only 60 MSD, and 60 mg/kg FSD respectively. Biochemical parameters such as liver and kidney function tests, lipid profile, as well as lipid peroxidation and antioxidant enzymes were assessed in addition to histopathology. Results: It was observed that daily oral administration of MSD and FSD for 21 days significantly (p < 0.05) improved the observed pathological changes as a result of type 2 diabetes. Conclusion: It could be deduced from results obtained in this study that methanolic and flavonoid-rich leaf extracts of S.dulcificum have antidiabetic potential in type 2 diabetic rats

Proteomic Quantitative UV Absorption Spectrum Analysis of Effect of Heat Stress on Protein Extract from Cowpea Seed (Vigna unguiculata (L) Walp)

Aim: Proteomic quantitative UV absorption spectrum analysis was used to study the effect of heat stress on protein extract from cowpea seeds (Vigna unguiculata (L) Walp). Study Design: Protein extracts were obtained from 9 cowpea accessions obtained from GeneBank of International Institute of Tropical Agriculture in January 2014. Each protein extract was divided into four batches out of which three batches were subjected to different temperature treatments and incubation at 37°C, 60°C and 100°C for 1 hour and the remaining one batch served as control. Protein content in each control protein extract and 37°C, 60°C and 100°C treated protein extracts from each of the 9 cowpea samples were determined at 280 nm using bovine serum albumin standard curve. Place and Duration of Study: Biochemistry Unit, Department of Chemical Sciences, Afe Babalola University Ado Ekiti, Nigeria between January 2014 and June 2014. Methodology: A200-A960 UV wavelengths absorption spectrum analysis was carried out on control protein extract and 37°C, 60°C and 100°C treated protein extracts respectively from each of the 9 cowpea samples. In order to establish the relationship between protein extracts (control) and protein extracts heat treated (37°C, 60°C, and 100°C), cluster analysis of optical density (OD) data was carried out using numerical taxonomy and multivariate analysis system. Results: The protein content (control) in Vigna unguiculata (L) Walp was between 8.4 and 10.8 mg/ml (10.5-13.5%) in seed, while protein content (heat treated) in Vigna unguiculata (L) Walp was between 8.9 and 9.5 mg/ml (11.2-11.9%), 8.7-9.5 mg/ml (10.9-11.9%), 9.0 and 11.8 mg/ml (11.3- 14.7 %) in heat treatments of 37°C, 60°C, and 100°C respectively. The protein UV absorption spectra of control protein extract and 37°C, 60°C and 100°C treated protein extracts from each cowpea accession were generally different due to differential UV wavelength protein absorption. Cluster analysis of absorbance spectra optical density values revealed five clusters (cluster 1, cluster 2, cluster 3, cluster 4, and cluster 5) among control protein extracts and protein extracts heated at 37°C, 60°C, and 100°C. Cluster1 was made up of protein extracts heated at 37°C and 60°C, while cluster2 and cluster3 constituted closely related protein extracts heated at 37°C and 100°C respectively. Cluster4 was typical of control protein extracts, while cluster5 was made up of distinct protein extracts heated at 100°C. Conclusion: Heating protein extracts at 37°C, 60°C, and 100ºC has altered proteomic diversity in different cowpea accessions and this could make protein extraction more difficult with implications on protein properties

Proteomic Quantitative UV Absorption Spectrum Analysis of Effect of Heat Stress on Protein Extract from Cowpea Seed (Vigna unguiculata (L) Walp)

Aim: Proteomic quantitative UV absorption spectrum analysis was used to study the effect of heat stress on protein extract from cowpea seeds (Vigna unguiculata (L) Walp). Study Design: Protein extracts were obtained from 9 cowpea accessions obtained from GeneBank of International Institute of Tropical Agriculture in January 2014. Each protein extract was divided into four batches out of which three batches were subjected to different temperature treatments and incubation at 37°C, 60°C and 100°C for 1 hour and the remaining one batch served as control. Protein content in each control protein extract and 37°C, 60°C and 100°C treated protein extracts from each of the 9 cowpea samples were determined at 280 nm using bovine serum albumin standard curve. Place and Duration of Study: Biochemistry Unit, Department of Chemical Sciences, Afe Babalola University Ado Ekiti, Nigeria between January 2014 and June 2014. Methodology: A200-A960 UV wavelengths absorption spectrum analysis was carried out on control protein extract and 37°C, 60°C and 100°C treated protein extracts respectively from each of the 9 cowpea samples. In order to establish the relationship between protein extracts (control) and protein extracts heat treated (37°C, 60°C, and 100°C), cluster analysis of optical density (OD) data was carried out using numerical taxonomy and multivariate analysis system. Results: The protein content (control) in Vigna unguiculata (L) Walp was between 8.4 and 10.8 mg/ml (10.5-13.5%) in seed, while protein content (heat treated) in Vigna unguiculata (L) Walp was between 8.9 and 9.5 mg/ml (11.2-11.9%), 8.7-9.5 mg/ml (10.9-11.9%), 9.0 and 11.8 mg/ml (11.3- 14.7 %) in heat treatments of 37°C, 60°C, and 100°C respectively. The protein UV absorption spectra of control protein extract and 37°C, 60°C and 100°C treated protein extracts from each cowpea accession were generally different due to differential UV wavelength protein absorption. Cluster analysis of absorbance spectra optical density values revealed five clusters (cluster 1, cluster 2, cluster 3, cluster 4, and cluster 5) among control protein extracts and protein extracts heated at 37°C, 60°C, and 100°C. Cluster1 was made up of protein extracts heated at 37°C and 60°C, while cluster2 and cluster3 constituted closely related protein extracts heated at 37°C and 100°C respectively. Cluster4 was typical of control protein extracts, while cluster5 was made up of distinct protein extracts heated at 100°C. Conclusion: Heating protein extracts at 37°C, 60°C, and 100ºC has altered proteomic diversity in different cowpea accessions and this could make protein extraction more difficult with implications on protein properties