Bioactivity-guided fractionation of Coronopus didymus: A free radical scavenging perspective

The whole plant aqueous extract of Coronopus didymus Linn. was fractionated on the basis of polarity and resulting fractions were evaluated for free radical scavenging ability. The most non-polar fraction (CDF1) was found to be more active than other fractions in scavenging DPPH, ABTS(-), nitric oxide and hydroxyl radicals in steady-state conditions. Stop-flow spectrometric studies showed 58.13% inhibition of 100 microM DPPH at a concentration of 150 microg/ml of CDF1 in 1000 s and 32.31% scavenging of 960 microM ABTS(-) at a concentration of 300 microg/ml of CDF1 in 100 s. The reaction of CDF1 with hydroxyl radicals produced by pulse radiolysis showed a transient spectrum with absorption peaks at 320, 390 and 400 nm, indicating the presence of flavonoids/related components. Competition kinetics with potassium thiocyanate against scavenging of hydroxyl radicals showed a reactivity of 0.1326 against thiocyanate. CDF1 also protected against Fenton reagent-induced calf thymus DNA damage at a concentration of 400 mg/ml indicating it to be the most potent fraction.     

Heterologous expression and biochemical characterization of acetyl xylan esterase from Coprinopsis cinerea

Acetyl xylan esterase (AXE) from basidiomycete Coprinopsis cinerea Okayama 7 (#130) was functionally expressed in Pichia pastoris with a C-terminal tag under the alcohol oxidase 1 (AOX1) promoter and secreted into the medium at 1.5 mg l^?1. Its molecular mass was estimated to be 65.5 kDa based on the SDS-PAGE analysis, which is higher than the calculated molecular mass of 40 kDa based on amino acid composition. In-silico analysis of the amino acid sequence predicted two potential N-glycosylation sites. Results from PNGase F deglycosylation and mass spectrum confirmed the presence of N-glycosylation on the recombinant AXE with predominant N-glycans HexNAc₂Hex_9–16. The recombinant AXE showed best activity at 40 °C and pH 8. It showed not only acetyl esterase activity with a K_m of 4.3 mM and a V_max of 2.15 U mg^?1 for hydrolysis of 4-nitrophenyl acetate but also a butyl esterase activity for hydrolysis of 4-nitrophenyl butyrate with a K_m of 0.11 mM and V_max of 0.78 U mg^?1. The presence of two additional amino acid residues at its native N-terminus was found to help stabilize the enzyme against the protease cleavages without affecting its activity.     

Synonymous codon usage pattern among the S,M, and L segments in Crimean-congo hemorrhagic fever virus

Crimean-Congo hemorrhagic fever (CCHF) virus is one among the major zoonosis viral diseases that use the Hyalomma ticks as their transmission vector to cause viral infection to the human and mammalian community. The fatality of infectious is high across the world especially in Africa, Asia, Middle East, and Europe. This study regarding codon usage bias of S, M, and L segments of the CCHF virus pertaining to the host Homo sapiens, reveals in-depth information about the evolutionary characteristics of CCHFV. Relative Synonymous Codon Usage (RSCU), Effective number of codons (ENC) were calculated, to determine the codon usage pattern in each segment. Correlation analysis between Codon adaptation index (CAI), GRAVY (Hydrophobicity), AROMO (Aromaticity), and nucleotide composition revealed bias in the codon usage pattern. There was no strong codon bias found among any segments of the CCHF virus, indicating both the factors i.e., natural selection and mutational pressure shapes the codon usage bias.     

Bacopa monniera (L.) Wettst ameliorates behavioral alterations and oxidative markers in sodium valproate induced autism in rats

Early prenatal or post natal exposure to environmental insults such as valproic acid (VPA), thalidomide and ethanol could induce behavioral alterations similar to autistic symptoms. Bacopa monniera, a renowned plant in ayurvedic medicine is useful in several neurological disorders. The purpose of the present study was to evaluate the effect of B. monniera on VPA induced autism. On 12.5 day of gestation the female pregnant rats were divided into control and VPA treated groups. They were administered saline/VPA (600 mg/kg, i.p.) respectively and allowed to raise their own litters. Group I—male pups of saline treated mothers. On postnatal day (PND) 21 VPA induced autistic male pups were divided into two groups (n = 6); Group II—received saline and Group III—received B. monniera (300 mg/kg/p.o.) from PND 21–35. Behavioral tests (nociception, locomotor activity, exploratory activity, anxiety and social behavior) were performed in both adolescence (PND 30–40) and adulthood (PND 90–110) period. At the end of behavioral testing animals were sacrificed, brain was isolated for biochemical estimations (serotonin, glutathione, catalase and nitric oxide) and histopathological examination. Induction of autism significantly affected normal behavior, increased oxidative stress and serotonin level, altered histoarchitecture of cerebellum (decreased number of purkinje cells, neuronal degeneration and chromatolysis) when compared with normal control group. Treatment with B. monniera significantly (p < 0.05) improved behavioral alterations, decreased oxidative stress markers and restored histoarchitecture of cerebellum. In conclusion, the present study suggests that B. monniera ameliorates the autistic symptoms possibly due to its anti-anxiety, antioxidant and neuro-protective activity.     

Salt-induced hypertension in WKY rats: Prevention by α-lipoic acid supplementation

There is strong evidence that points to excess dietary salt as a major factor contributing to the development of hypertension. Salt sensitivity is associated with glucose intolerance and insulin resistance in both animal models and humans. In insulin resistance, impaired glucose metabolism leads to elevated endogenous aldehydes which bind to vascular calcium channels, increasing cytosolic [Ca²⁺]_i and blood pressure. In an insulin resistant animal model of hypertension, spontaneously hypertensive rats (SHRs), dietary supplementation with lipoic acid lowers tissue aldehydes and plasma insulin levels and normalizes blood pressure. The objective of this study is to examine the effects of a high salt diet on tissue aldehydes, cytosolic [Ca²⁺]_i and blood pressure in WKY rats and to investigate whether dietary supplementation with lipoic acid can prevent a salt induced increase in blood pressure. Starting at 7 weeks of age, WKY rats were divided into three groups of six animals each and treated for 10 weeks with diets as follows: WKY-normal salt (0.7% NaCl); WKY-high salt (8% NaCl); WKY-high salt + lipoic acid (8% NaCl diet + lipoic acid 500 mg/Kg feed). At completion, animals in the high salt group had elevated systolic blood pressure, platelet [Ca²⁺]_i, and tissue aldehyde conjugates compared with the normal salt group and showed smooth muscle cell hyperplasia in the small arteries and arterioles of the kidneys. Dietary -lipoic acid supplementation in high salt-treated WKY rats normalized systolic blood pressure and cytosolic [Ca²⁺]_i and aldehydes in liver and aorta. Kidney aldehydes and renal vascular changes were attenuated, but not normalized.     

Microbial production of lactic acid: the latest development

Lactic acid is an important platform chemical for producing polylactic acid (PLA) and other value-added products. It is naturally produced by a wide spectrum of microbes including bacteria, yeast and filamentous fungi. In general, bacteria ferment C5 and C6 sugars to lactic acid by either homo- or hetero-fermentative mode. Xylose isomerase, phosphoketolase, transaldolase, l- and d-lactate dehydrogenases are the key enzymes that affect the ways of lactic acid production. Metabolic engineering of microbial strains are usually needed to produce lactic acid from unconventional carbon sources. Production of d-LA has attracted much attention due to the demand for producing thermostable PLA, but large scale production of d-LA has not yet been commercialized. Thermophilic Bacillus coagulans strains are able to produce l-lactic acid from lignocellulose sugars homo-fermentatively under non-sterilized conditions, but the lack of genetic tools for metabolically engineering them severely affects their development for industrial applications. Pre-treatment of agriculture biomass to obtain fermentable sugars is a pre-requisite for utilization of the huge amounts of agricultural biomass to produce lactic acid. The major challenge is to obtain quality sugars of high concentrations in a cost effective-way. To avoid or minimize the use of neutralizing agents during fermentation, genetically engineering the strains to make them resist acidic environment and produce lactic acid at low pH would be very helpful for reducing the production cost of lactic acid.     

An adaptive benefit of facultative coprophagy in the German cockroach Blattella germanica

1. A possible adaptive benefit of coprophagy was investigated in nymphs of the German cockroach Blattella germanica (L.). 2. Newly ecdysed first instars, given no source of food other than conspecific faeces, survived significantly longer than first instars deprived of faeces. The faeces of adult males and females may be of different quality, however, because nymphs given female faeces were more likely to moult into the second stadium than nymphs given male faeces. 3. In contrast to first instars, second instars provided adult faeces survived only slightly longer than starved counterparts. Faecal feeding is therefore stage‐specific, as is the benefit derived from it. 4. The relationship between the nutrient composition of faeces and the survival of nymphs was also examined. First instars fed the faeces of adults that had been maintained on a high (50%) protein diet, died more slowly than first instars fed the faeces of adults that had been maintained on medium (22.5%) and low (5%) protein diets. Chemical analysis of faeces showed that the concentration of protein in adult faeces increased with the level of protein in the diet. Moreover, food choice assays showed that first instars, unlike adults, ingested more of the high‐protein diets. 5. These data support the idea that coprophagy is a stage‐specific adaptive behaviour that permits first instars to moult into the second stadium with minimal foraging.     

Environmental Response and Genomic Regions Correlated with Rice Root Growth and Yield under Drought in the OryzaSNP Panel across Multiple Study Systems

The rapid progress in rice genotyping must be matched by advances in phenotyping. A better understanding of genetic variation in rice for drought response, root traits, and practical methods for studying them are needed. In this study, the OryzaSNP set (20 diverse genotypes that have been genotyped for SNP markers) was phenotyped in a range of field and container studies to study the diversity of rice root growth and response to drought. Of the root traits measured across more than 20 root experiments, root dry weight showed the most stable genotypic performance across studies. The environment (E) component had the strongest effect on yield and root traits. We identified genomic regions correlated with root dry weight, percent deep roots, maximum root depth, and grain yield based on a correlation analysis with the phenotypes and aus, indica, or japonica introgression regions using the SNP data. Two genomic regions were identified as hot spots in which root traits and grain yield were co-located; on chromosome 1 (39.7–40.7 Mb) and on chromosome 8 (20.3–21.9 Mb). Across experiments, the soil type/ growth medium showed more correlations with plant growth than the container dimensions. Although the correlations among studies and genetic co-location of root traits from a range of study systems points to their potential utility to represent responses in field studies, the best correlations were observed when the two setups had some similar properties. Due to the co-location of the identified genomic regions (from introgression block analysis) with QTL for a number of previously reported root and drought traits, these regions are good candidates for detailed characterization to contribute to understanding rice improvement for response to drought. This study also highlights the utility of characterizing a small set of 20 genotypes for root growth, drought response, and related genomic regions.     

Effect of sesamol on radiation-induced cytotoxicity in Swiss albino mice

The radio-protective ability of sesamol (SM) at various doses viz., 0, 10, 25, 40, 50, 70 and 100 mg/kg bw, administered intraperitoneally 30 min prior to 9.5 Gy whole-body γ-irradiation was studied in Swiss albino mice. Radiation toxicity and mortality were observed during a period of 30 days and the percentage mortality was calculated. SM pretreatment with 50 mg/kg bw was found to be the most effective dose in maintaining body weight and in reducing the percentage mortality, while 100 mg/kg bw was found to be more effective in maintaining the spleen index and in stimulation of endogenous spleen colony-forming units. Pretreatment with SM (50 mg/kg bw) in mice irradiated with 15 Gy significantly reduced dead, inflammatory, mitotic and goblet cells in irradiated jejunum. SM at 50 mg/kg bw also increased crypt cells, maintained villus height, and prevented mucosal erosion. Nuclear enlargement in epithelial cells was found less in SM-treated mice compared with the irradiated control. The radiation-induced decrease in endogenous antioxidant enzymes (GSH, GST, catalase) and the increase in lipid peroxidation were also reduced by pretreatment with SM [50 and 100 mg/kg bw] at all monitored post-irradiation intervals. There was no protection at a dose less than 25 mg/kg bw.