Isolation and characterization of 2-hydroxy-9,10-anthraquinone from Streptomyces olivochromogenes (ERINLG-261) with antimicrobial and antiproliferative properties

Abstract Currently Streptomyces is one of the most important antibiotic producing microorganisms against several diseases. In the present study Streptomyces olivochromogenes ERINLG-261 was isolated from the soil samples of the Mudumalai hills, Western Ghats, India. Morphological, physiological, biochemical and 16S rRNA studies strongly suggested that this isolate belonged to the genus Streptomyces. ERINLG-261 showed good antimicrobial activity against different bacteria and fungi in Micromonospora fermentation medium. The active ethyl acetate extract was packed in column chromatography over silica gel which led to the isolation of 2-hydroxy-9,10-anthraquinone as the active principle. The isolated compound showed good antimicrobial activity against tested bacteria and fungi in minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) studies. The compound showed moderate in vitro antiproliferative activity against A549 and COLO320 cells. The compound was subjected to molecular docking studies for the inhibition of Topoisomerase, TtgR and Beta-lactamase enzymes which are targets for antimicrobials. Docking results of the compound showed low docking energy with these enzymes indicating its usefulness as antimicrobial agent. This is the first report of antimicrobial and antiproliferative activity of 2-hydroxy-9,10-anthraquinone isolated from Streptomyces olivochromogenes along with molecular docking studies.

Nutritional Evaluation, in vitro Free Radical Scavenging and in vivo Anti-inflammatory Effects of Gisekia pharnaceoides and Identification of Kaempferol as a Nutraceutical Agent.

Aims: To analyse the nutritional profile and assess the antioxidant and antiinflammatory activities of Gisekia pharnaceoides wild plant used as traditional food source for dietary supplementation and to identify the bioactive compound as the nutraceutical agent. Study design: In vitro and In vivo studies. Place and Duration of Study: Department of Biotechnology, CSIR-Central Leather Research Institute, Chennai-600020, India and Sri Ramachandra College of Pharmacy, Sri Ramachandra University, Chennai-600116 between October 2005 and December 2007. Methodology: Dry powder of the whole plant of Gisekia pharnaceoides was used for determining the nutritional parameters. Vitamins were estimated as per Indian Pharmacopoeia and United States Pharmacopoeia methods. Mineral composition was determined using Atomic absorption spectroscopy. Proximate analysis of plant power was carried out according to AOAC methods. Solvent extracts of the plant were assessed for free radical scavenging activities in vitro and antiinflammatory activity in vivo. UV, IR, NMR and LC-MS spectroscopy were used for identification of the bioactive compound. Results: A markedly increased composition of vitamins such as thiamine, riboflavin, ascorbic acid and vitamin A and a wide range of minerals of metabolic importance have been estimated with high nutritive value. Additionally, the plant contained 9% protein and about 3% fat and carbohydrate content to an extent of 69%, of which 8% was crude fibre. All three extracts exhibited a high degree of free radical scavenging ability against DPPH radical, NO•, OH•, ABTS•+, O2 • -. The methanol fraction showed increased levels of antioxidant and anti-inflammatory activities compared to the other two extracts because of the presence of a flavonoid which was identified as kaempferol using UV, FTIR, NMR and LC-MS spectroscopy. Conclusion: Gisekia pharnaceoides could therefore serve as a potential nutraceutical to prevent or inhibit the harmful oxidation process in human pathophysiology, and, is a high value nutritive source as a dietary supplement to prevent malnutrition especially in rural population. Therefore, we suggest the dietary intake of the plant for nutritional supplementation.