Maryam Varasteh-kojourian; Ali Ganjeali; Javad Asili; Saeid Malekzadeh-Shafaroudi; Akram Taleghani
Abstract
Endophytic fungi are often producing host plant metabolites. Tanshinones are secondary metabolites of the Salvia genus which are also produced by some endophytic fungi. Efficient secondary metabolite production in endophytic fungi drops significantly after sequential subcultures. 5-azacytidine (5-AC) ...
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Endophytic fungi are often producing host plant metabolites. Tanshinones are secondary metabolites of the Salvia genus which are also produced by some endophytic fungi. Efficient secondary metabolite production in endophytic fungi drops significantly after sequential subcultures. 5-azacytidine (5-AC) is an analog of the naturally occurring pyrimidine nucleoside cytidine and a DNA methyltransferase inhibitor. In this relation, 5-AC is an effective tool to induce the expression of silenced secondary metabolite genes in fungi. We isolated 4 endophytic fungi from the roots of Salvia abrotanoides which produced tanshinone. Cryptotanshinone and tanshinone IIA were produced by Penicillium canescens, Penicillium nodositatum, and Penicillium pinophilum, while Paraphoma radicina only produced tanshinone IIA. The maximum amount of tanshinones was extracted from P. pinophilum culture with 130.826 mg cryptotanshinone /g of dry weight and 50.155 mg Tanshinone IIA/g of dry weight. These amounts were significantly more than tanshinones produced in plant roots (0.55 mg cryptotanshinone/g of dry weight, 1.3 mg Tanshinone IIA/g of dry weight). In the third subculture, tanshinone production decreased significantly. 5-azacytidine as an epigenetic modifier retrieved tanshinone production in the third subculture of P. pinophilum. Also, 5- azacytidine treatment made a big jump in Tanshinone IIA production in P. radicina (63.176 mg TIIA/g of dry weight) besides increasing Tanshinone IIA production in P. nodositatum cultures. This is the first report using 5- azacytidine to improve tanshinone production in endophytic fungi. Our results confirm that 5- azacytidine is an efficient, easy, and quick chemical to felicitate secondary metabolite production in endophytic fungi.
Samaneh Jamshidi; Mehrdad Lahouti; Mohammad Taher Boroushaki; Ali Ganjeali; Ahmad Ghorbani; Mehdi Bihamta toosi
Abstract
Diosgenin is an important compound in pharmaceutical industry. It has various effects such as hypocholesterolemic action or antioxidant activity in HIV infected patients. Biological oxidation pathways are involved in causing or aggravating heart disease. This study investigated the potential protective ...
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Diosgenin is an important compound in pharmaceutical industry. It has various effects such as hypocholesterolemic action or antioxidant activity in HIV infected patients. Biological oxidation pathways are involved in causing or aggravating heart disease. This study investigated the potential protective effect of diosgenin on cell viability and antioxidant defenses of cultured H9C2 cells submitted to oxidative stress induced by H2O2. Viability of cells exposed to H2O2 was detected by MTT assay. The generation of ROS and hydrogen peroxide release after H2O2 were detected using the fluorescent probe H2DCF-DA. The lipid peroxidation product i.e. MDA formation was estimated by assessing the levels of thio-barbituric acid reactive substances (TBARS) using spectrophotometry. SOD activity was assayed with NWLSS (TM) Superoxide Dismutase (SOD) activity assay kit. Pretreatment of cells with 3-25 µM of diosgenin for 24 h before applying H2O2 completely prevented cell damage and significantly enhanced viability of H9C2 cells. Increased ROS induced by H2O2 was dose dependently prevented when cells were pretreated for 24 h with diosgenin. The level of the lipid peroxidation was significantly higher in H9C2 cells exposed to H2O2 as compared to the control and cells pretreated with diosgenin. SOD activity in cells treated with diosgenin significantly decreased compared with cells exposed to H2O2. These results show that treatment of H9C2 cells with diosgenin (3-25 µM) confers a significant protection against oxidative stress.
