Evaluation of biological activities of Physalis peruviana ethanol extracts and expression of Bcl-2 genes in HeLa cells

Physalis species are used in folk medicine for phytotherapeutic properties. The extracts of medicinal plants are known to possesscytotoxic and chemopreventative compounds. In this study we investigated antibacterial, antioxidant, DNA damage preventativeproperties of Physalis peruviana (golden berry) on leaf and shoot ethanol extracts and their effects on cytotoxicity of HeLa cellsand expression of apoptotic pathway genes. Among the tested bacteria for antibacterial activity, maximum inhibition zone wasdetermined in Lactococcus lactis. The phenolic content was found higher in leaf extracts than shoot extracts. The antioxidantactivity showed the highest TEAC values of the leaf (2 mg/mL) and the shoot (0.5 mg/mL) extracts as 0.291±0.04 and 0.192±0.015,respectively. In DNA damage prevention assay both leaf and shoot extracts, especially 30 and 20 µg/mL concentrations, exhibitedsignificant protection against DNA damage-induced by hydroxyl radical generated by Fenton reaction. Our results suggest thatleaf and shoot extracts possess cytotoxic effect on HeLa cells when applied as 100 µg/mL concentration. Also mRNA expressionanalysis showed the alteration of antiapoptotic genes, so the results suggest that P. peruviana ethanol extracts induce apoptoticcell death and should be investigated for identification of active compounds and their mechanisms of action.

Defensive and secondary metabolism in Astragalus chrysochlorus cell cultures, in response to yeast extract stressor.

In this study it was aimed to investigate inducibility of secondary metabolism in Astragalus chrysochlorus by yeast extract which is known to cause the synthesis of defensive phenolic metabolites. Cell suspension cultures of Astragalus chrysochlorus responded to elicitor treatment (10 gl-1 yeast extract) by increasing phenylalanine ammonia lyase (PAL E.C. 4.3.1.5) activity, the key enzyme of phenylpropanoid pathway and accumulation of phenolic compounds. Yeast extract was added on 13th day in the cultures when cells were at early stage of logarithmic phase. The highest PAL activity (2.71 U μg protein-1 min-1) was measured at 36 hr after addition of yeast extract and increasing of total phenolics accompanied with 221 μg g-1 value as fresh weight (FW). Total phenolic content reached maximum value, 343.86 μg g-1 FW, at 48 hr while control’s value was 162 μg g-1 FW. Maximum PAL activity and total phenolic content were 2.88 and 2.12 times higher than the controls of A. chrysochlorus cells, respectively. Our results indicate that there is a positive correlation between induced PAL activity and accumulation of total phenolics. It is considered that early defense response given to environmental stressors such as biotic and abiotic factors by upregulation of phenolic branch of secondary metabolism occurs in A. chrysochlorus with addition of yeast extract.