The constant exposure to solar ultraviolet radiation (UV) has a variety of harmful effects on human health. Although synthetic sunscreen products have been introduced as a preventive/therapeutic strategy, with the realization of their adverse side effects, the recent trend is to search for human friendly alternative formulations especially of plant origin. Therefore, the present study focuses on evaluation of photoprotective activity of aqueous extracts (1 mg/ml) of eleven medicinal plants in Sri Lanka that have been widely employed in traditional medicine as treatment options for various skin diseases and to improve the complexion. For the determination of UV filtering potential of the extracts, UV absorption was measured and the sun protection factor (SPF) was calculated according the Mansur equation. The antioxidant activity was evaluated by DPPH and ABTS assays. Among the extracts, Atalantia ceylanica, Hibiscus furcatus, Leucas zeylanica, Mollugo cerviana, Olax zeylanica and Ophiorrhiza mungos have displayed SPF value ≥ 25, which are even higher than two commercial photoprotective creams used as reference compounds. L. zeylanica and O. mungos have displayed a high UV absorbance in 260–350 nm range indicating their potential of being broad spectrum sunscreens. In addition, the extract of O. mungos was found to be photostable, without any significant reduction in the SPF after exposure to direct solar radiation for 21 days. DPPH assay and the ABTS assay revealed that the extracts possess high antioxidant activity. The results of the present study suggest that the presence of secondary metabolites with antioxidant property could be responsible for the high UV absorbance. Our findings would offer an exciting avenue for further research towards the development of herbal cosmetics.

An endophytic fungus Pestalotiopsis microspora isolated from the fruits of Manilkara zapota was cultured in potato dextrose broth media. Chromatographic separation of the EtOAc extract of the broth and mycelium led to the isolation of a new azaphilonoid named pitholide E (1), in addition to previously identified pitholide B (2), pitholide D (3), pestalotin (LL-P880α) (4), PC-2 (5), LL-P880β (6), tyrosol (7) and 4-oxo-4H-pyran-3-acetic acid (8). An endophytic fungus P. microspora from M. zapota and the isolation of compounds 1–5, 7 and 8 from P. microspora are reported here for the first time. Graphic

A fungal endophyte isolated from the leaves of the allelopathic plant Amaranthus viridis of the family Amaranthaceae was identified as Chaetomium globosum through molecular means using internal transcribed spacer (ITS) region of rDNA gene. This is the first report of the isolation of C. globosum from Amaranthaceae. Chromatographic separation of the EtOAc extract of the fungal fermentation in potato dextrose broth yielded two known chlorine-containing azaphilone derivatives, chaetomugilin D (1) and chaetomugilin J (2). Compounds 1 and 2 were found to show phytotoxic activity in the lettuce (Lactuca sativa) seed germination bioassay. The IC₅₀ values of 1 and 2 for root growth inhibition were 24.2 and 22.6 ppm, respectively, while IC₅₀ values for shoot growth inhibition were 27.8 and 21.9 ppm, respectively. Phytotoxic activities of the chaetomugilin group of compounds have been reported for the first time, although their antifungal, antimicrobial and cytotoxic activities are known.

Bipolaris sorokiniana, a fungal endophyte, was isolated from the leaves of Costus speciosus, a popular medicinal plant used to control diabetes. Fermentation of the fungus in potato dextrose broth and chromatographic purification of the ethyl acetate (EtOAc) extracts of the culture broth and mycelium yielded two rare sesquiterpenes helminthosporal acid (1) and helminthosporol (2), together with ergosterol. Compounds 1 and 2 showed a strong phytotoxic effect on lettuce seed germination and toxicity against brine shrimps. Compound 1 also showed antifungal activity. Complete assignments of ¹H and ¹³C NMR data of compound 1 are described for the first time.