Antioxidant and Antidiabetic Properties of Extracts from Three Underutilized Food Plants of North East India

Three underutilized leafy vegetables Sarcochlamys pulcherrima (Roxb.) Gaudich (SP), Ipomoea aquatica Forssk. (IA) and Zanthoxylum rhetsa (Roxb.) DC (ZR) were extracted with different solvents viz. 95 % ethyl alcohol, methanol and hot water. The extracts were evaluated for their antioxidant potential via DPPH, ABTS and FRAP assay along with electroanalytical studies using cyclic voltammetry. The antidiabetic potential was determined by recording their α-amylase and α-glucosidase inhibitory assay. The total phenolic content (TPC), total flavonoid content (TFC) and the liquid chromatography-mass spectrometry (LC/MS) based phytochemical profiles of the extracts were also determined. All three extracts of SP exhibited significant antioxidant capacity. The antidiabetic potential of the IA and ZR extracts was found to be higher than or at par with that of standard acarbose. LC/MS studies reveal the presence of hitherto reported antioxidant and antidiabetic compounds like gamma-aminobutyric acid, cinnamic acid, caffeic acid, α-viniferin, piperlonguminine, niacin, kaempferol, etc., in the extracts.     

Colorimetric determination of L-phenylacetyl carbinol produced by biotransformation of benzaldehyde and pyruvate using Saccharomyces cerevisiae

Summary The utility of a colorimetric method, based on the Voges-Proskauer reaction, for L-phenylacetyl carbinol (L-PAC) determination has been evaluated. The relative absorbances observed for equivalent concentrations of L-PAC and acetylbenzoyl at 580 nm were determined. L-PAC manifested a lower absorbance (60–68%) than the equivalent acetylbenzoyl concentration.     

Sugar and phosphate metabolism and alkaloid production phases in submerged cultures of two Claviceps strains

Summary In submerged cultures of Claviceps sp. CP II, elymoclavine was synthesized only by the growing mycelium (phase P1), whereas cultures of C. purpurea strain 129 produced agroclavine after vegetative growth had also ceased (phase P2). In strain CP II, the peak of activity of malate dehydrogenase, glucose-6-phosphate dehydrogenase and phosphatases was related to the time of maximum growth rate and alkaloid production. Citrate synthase activity paralleled the course of alkaloid synthesis. Strain 129 exhibited a further activity peak of the same magnitude during phase P2. ATP levels in both cultures corresponded to the pattern of change in enzyme activities. Strain CP II contained roughly twice as much orthophosphate and ATP in its cells as strain 129 and exhibited higher average activity of glucose-6-phosphate dehydrogenase. It follows from these results that alkaloid synthesis requires the processes of primary metabolism, even when it occurs after active growth of the culture has ceased. Cultures producing alkaloids oxidized at C-8 exhibit higher glucose-6-phosphate dehydrogenase activity, probably because of a higher NADPH consumption.     

Rac1-NADPH oxidase-regulated generation of reactive oxygen species mediates glutamate-induced apoptosis in SH-SY5Y human neuroblastoma cells

Reactive oxygen species (ROS) are known to play an important role in glutamate-induced neuronal cell death. In the present study, we examined whether NADPH oxidase serves as a source of ROS production and plays a role in glutamate-induced cell death in SH-SY5Y human neuroblastoma cells. Stimulation of the cells with glutamate (100 mM) induced apoptotic cell death and increase in the level of ROS, and these effects of glutamate were significantly suppressed by the inhibitors of the NADPH oxidase, diphenylene iodonium, apocynin, and neopterine. In addition, RT-PCR revealed that SH-SY5Y cells expressed mRNA of gp91^phox, p22^phox and cytosolic p47^phox, p67^phox and p40^phox, the components of the plasma membrane NADPH oxidase. Treatment with glutamate also resulted in activation and translocation of Rac1 to the plasma membrane. Moreover, the expression of Rac1N17, a dominant negative mutant of Rac1, significantly blocked the glutamate-induced ROS generation and cell death. Collectively, these results suggest that the plasma membrane-bound NADPH oxidase complex may play an essential role in the glutamate-induced apoptotic cell death through increased production of ROS.     

Reward‐related ventral striatum reactivity mediates gender‐specific effects of a galanin remote enhancer haplotype on problem drinking

The neuropeptide galanin has been implicated in the regulation of appetitive and consummatory behaviors. Prior studies have shown that direct injection of galanin into the hypothalamus results in increased release of dopamine (DA) in the nucleus accumbens (NAcc), and parallel increases in food and alcohol consumption. These studies are consistent with a role of hypothalamic galanin in regulating reward system reactivity. In humans, a common functional haplotype (GAL5.1) within a remote enhancer region upstream of the galanin gene (GAL) affects promoter activity and galanin expression in hypothalamic neurons in vitro. Given the effects of hypothalamic galanin on NAcc DA release and the effects of the GAL5.1 haplotype on GAL expression, we examined the impact of this functional genetic variation on human reward‐related ventral striatum (VS) reactivity. Using an imaging genetics strategy in Caucasian individuals (N = 138, 72 women) participating in the ongoing Duke Neurogenetics Study, we report a significant gender‐by‐genotype interaction (right hemisphere: F_1,134 = 8.08, P = 0.005; left hemisphere: F_1,134 = 5.39, P = 0.022), such that homozygosity for the GG haplotype, which predicts greater GAL expression, is associated with relatively increased VS reactivity in women (n = 50, right hemisphere: P = 0.015; left hemisphere: P = 0.060), but not in men (N = 49, P‐values > 0.10). Furthermore, these differences in VS reactivity correlated positively with differences in alcohol use, such that VS reactivity mediated a gender‐specific association between GAL5.1 haplotype and problem drinking. Our current results support those in animal models implicating galanin signaling in neural pathways associated with appetitive and consummatory behaviors of relevance for understanding risk for substance use and abuse.     

Inter‐α‐inhibitor deficiency in the mouse is associated with alterations in anxiety‐like behavior,exploration and social approach

In recent years, several genome‐wide association studies have identified candidate regions for genetic susceptibility in major mood disorders. Most notable are regions in a locus in chromosome 3p21, encompassing the genes NEK4‐ITIH1‐ITIH3‐ITIH4. Three of these genes represent heavy chains of the composite protein inter‐α‐inhibitor (IαI). In order to further establish associations of these genes with mood disorders, we evaluated behavioral phenotypes in mice deficient in either Ambp/bikunin, which is necessary for functional ITIH1 and ITIH3 complexes, or in Itih4, the gene encoding the heavy chain Itih4. We found that loss of Itih4 had no effect on the behaviors tested, but loss of Ambp/bikunin led to increased anxiety‐like behavior in the light/dark and open field tests and reduced exploratory activity in the elevated plus maze, light/dark preference and open field tests. Ambp/bikunin knockout mice also exhibited a sex‐dependent exaggeration of acoustic startle responses, alterations in social approach during a three‐chamber choice test, and an elevated fear conditioning response. These results provide experimental support for the role of ITIH1/ITIH3 in the development of mood disorders.     

Characterization and potential antitumor effect of a heteropolysaccharide produced by the red alga Porphyridium sordidum

Taking into account the rising trend of the incidence of cancers of various organs, effective therapies are urgently needed to control human malignancies. However, almost all chemotherapy drugs currently on the market cause serious side effects. Fortunately, several studies have shown that some non‐toxic biological macromolecules, including algal polysaccharides, possess anti‐cancer activities or can increase the efficacy of conventional chemotherapy drugs. Polysaccharides are characteristic secondary metabolites of many algae. The efficacy of polysaccharides on the normal and cancer cells is not well investigated, but our investigations proved a cell specific effect of a newly isolated extracellular polysaccharide from the red microalga Porphyridium sordidum. The investigated substance was composed of xylose:glucose and galactose:manose:rhamnose in a molar ratio of 1:0.52:0.44:0.31. Reversible electroporation has been exploited to increase the transport through the plasma membrane into the tested breast cancer tumor cells MCF‐7 and MDA‐MB231. Application of 75 µg/mL polysaccharide in combination with 200 V/cm electroporation induced 40% decrease in viability of MDA‐MB231 cells and changes in cell morphology while control cells (MCF10A) remained with normal morphology and kept vitality.     

Effects of age-dependent or liposome-induced alterations in the phospholipid composition on sphingomyelin biosynthesis in rat liver microsomal and plasma membranes.

1. The effects of age-dependent or liposome-induced alterations in the phospholipid composition of rat liver plasma and microsomal membranes on the phosphatidylethanolamine:ceramide-phosphoethanolamine (PE:Cer-PEt) and phosphatidylcholine:ceramide-phosphocholine (PC:Cer-PCh) transferase activities were studied. 2. In all cases under study the PE:Cer-PEt transferase activity was found to be several times higher than that of PC:Cer-PCh transferase in both plasma and microsomal rat liver membranes. 3. The presence of phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) in plasma membranes was observed to enhance the PE:Cer-PEt transferase activity, while phosphatidylserine (PS) inhibited it.     

A modified method for determination of diffusivities of low molecular substances in non-Newtonian liquids

A modified method for determination of diffusivities of low molecular substances in non-Newtonian liquids described by the power-law model has been proposed. It is based on the dissolution of Geiss body, with a parameter m=1/3 rotating in an infinite fluid. In this case, the solution of the differential equations of motion and mass transfer is available as an analytical formula for calculating the diffusivity coefficient.The method allows the extension of the variety of media and diffusing species. It has been illustrated with dissolving of gypsum in water and five non-Newtonian liquids. The results obtained have been interpreted taking into account the interaction between calcium ions and polymer molecules of the non-Newtonian system, as well as the heterogeneity of the system near to the dissolving surface.     

Lipids and sterols in Musca domestica L. (Diptera, Muscidae): changes after treatment with sucrose and lead

Total lipid, fatty acid and sterol composition of larvae and adults of Musca domestica was investigated before and after feeding on sucrose syrup or on the same syrup containing 1% lead nitrate. The effects of sucrose and of lead ions were found to be different. In larvae sucrose diet inhibited the fatty acid elongation and stimulated the first stages of their unsaturation. A significant increase of phytosterol concentrations was obtained. These changes increased the cell membrane permeability. The addition of lead caused a decrease of the fatty acid unsaturation, which decreased the cell membrane permeability. In adults the sucrose diet had no effect on the lipid and sterol composition, while the addition of lead decreased the cholesterol concentration. The composition of lipids and sterols also depends on the diet of larvae before pupation. The data obtained suggested that changes in lipid and sterol composition, which control the permeability of the cell membrane, might be an adaptive response of the organism to the changes of the environment.