Isaria tenuipes Peck, an entomopathogenic fungus from Darjeeling Himalaya: Evaluation of in-vitro antiproliferative and antioxidant potential of its mycelium extract.

BACKGROUND: Isaria tenuipes is one of the potent species in the members of the genus Isaria, which is well reported to possess multiple bioactive substances of therapeutic importance. Therefore, an in vitro experimental study was carried to evaluate the bioactivities of the crude methanolic extract from the mycelium of this fungus. METHODS: The fungus was authenticated through morphological characters and the species discrepancy was resolved using the nuclear rDNA ITS sequence. The methanolic extract was fingerprinted by FTIR. The antioxidant components in terms of total phenols and flavonoids were determined as gallic acid and quercetin equivalents respectively. Antioxidant activities of the methanolic extract was assessed using 1, 1-diphenyl-2-picrylhydrazyl (DPPH), 2, 2/-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid) radical cation (ABTS0+), Fe2+chelating activity, and hydroxyl radical scavenging assays. Cytotoxicity of the extract was determined by [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] (MTT) assay on three cancer cell lines: HeLa, HepG2, and PC3. Apoptosis was further studied by propidium iodide (PI) and Annexin-V/PI staining flow cytometric analysis. Anti-proliferation capacity was studied by colony-forming assay. RESULTS: In the present study total phenol content of the dried methanol extract was 148.09 ± 3.51µg gallic acid equivalent/mg and flavonoid was 9.02±0.95 µg quercetin/mg. The antioxidant activities of methanol-water extract (8:2 v/v) from cultured mycelia of I. tenuipes investigated and evaluated with 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay revealed IC50 value of 5.04mg/ml with an inhibition rate of 74.77% at 10mg/ml and with an iron-chelating assay the chelating ability was recorded to be 86.76% where the IC50 value was 4.43 mg/ml. In comparison among the antioxidant assays, 2,2/-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid) radical cation (ABTS0+) and hydroxyl assay exhibited radical scavenging rate of 44.42% and 49.82% respectively at a concentration of 10 mg/ml. The IC50 value of the extract in MTT assay was 43.45µg/ml with HeLa cells, 119.33µg/ml with PC3 cells, and 125.55µg/ml with HepG2 cells. CONCLUSION: In this study, it can be concluded that the crude methanolic extract exhibited potent antioxidant and antiproliferative activities suggesting natural antioxidative and antiproliferative agents.

Myo-Inositol and Its Derivatives: Their Emerging Role in the Treatment of Human Diseases.

Myo-inositol has been established as an important growth-promoting factor of mammalian cells and animals. The role of myo-inositol as a lipotropic factor has been proven, in addition to its involvement as co-factors of enzymes and as messenger molecules in signal transduction. Myo-inositol deficiency leads to intestinal lipodystrophy in animals and "inositol-less death" in some fungi. Of late, diverse uses of myo-inositol and its derivatives have been discovered in medicinal research. These compounds are used in the treatment of a variety of ailments from diabetes to cancer, and continued research in this direction promises a new future in therapeutics. In different diseases, inositols implement different strategies for therapeutic actions such as tissue specific increase or decrease in inositol products, production of inositol phosphoglycans (IPGs), conversion of myo-inositol (MI) to D-chiro-inositol (DCI), modulation of signal transduction, regulation of reactive oxygen species (ROS) production, etc. Though inositol pharmacology is a relatively lesser-known field, recent years of research has generated a critical mass of information on the subject. This review aims to summarize our current understanding on the role of inositol derivatives in ameliorating the symptoms of different diseases.

L-myo-inositol-1-phosphate synthase expressed in developing organ: isolation and characterisation of the enzyme from human fetal liver.

L-myo-inositol-1-phosphate synthase (MIPS; EC: 5.5.1.4) activity has been detected and partially purified for the first time from human fetal liver. Crude homogenate from the fetal liver was subjected to streptomycin sulphate precipitation and 0-60 % ammonium sulphate fractionation followed by successive chromatography through DEAE cellulose and BioGel A 0.5-m columns. After the final chromatography, the enzyme was purified 51-fold and 3.46 % of MIPS could be recovered. The human fetal liver MIPS specifically utilised D-glucose-6-phosphte and NAD(+) as its substrate and coenzyme, respectively. It shows pH optima between 7.0 and 7.5 while the temperature maximum was at 40 °C. The enzyme activity was remarkably stimulated by NH (4) (+) , slightly stimulated by K(+) and Ca(2+) and highly inhibited by Zn(2+), Cu(2+) and Hg(2+). The K (m) values of MIPS for D-glucose-6-phosphate and NAD(+) were found to be as 1.15 and 0.12 mM respectively while the V (max) values were 280 nM and 252 nM for D-glucose-6-phosphate and NAD(+) correspondingly. The apparent molecular weight of the native enzyme was determined to be 170 kDa.