Mycochemical screening, antioxidant evaluation and assessment of bioactivities of Xylaria papulis: A newly reported macrofungi from Paracelis, Mountain Province, Philippines

Abstract

Macrofungi is a diverse group of organisms that are known to be utilized by ancient people since earliest times for a number of their functions. In the Philippines, macrofungi have been part of the horticultural diversification of the people and were used by ethnic communities across the country. Xylaria papulis collected from Paracelis, Mountain Province have been assessed for its mycochemical, antioxidant, antibacterial, teratogenic and cytotoxic activities. Results showed that X. papulis exhibited secondary metabolites such as essential oil, triterpenes, coumarines, anthraquinones, tannins, flavonoids, anthrones, fatty acid, phenols, steroids and alkaloids. The recorded DPPH radical scavenging activity is 55.67%, however, it is lower than catechin with 71.13%. On the contrary, X. papulis exhibited high total phenolic content of 43.17 mg GAE/g. Moreover, the ethanolic extract of X. papulis showed a mean zone of inhibition ranging from 16-18 mm after 24 hours of incubation which is interpreted as an intermediate effect against Escherichia coli and Staphylococcus aureus. Furthermore, the teratogenic activity to the developing Danio rerio embryo showed that growth retardation, and head and tail malformations are the most notable effect. Mortality rates of the embryos were significantly high due to exposure to different concentrations of the X. papulis ethanol extract and the hatchability was completed after 48 hours for the concentrations ≤250 ppm. Abnormal heart beat rates, as well as pericardial edema causing weak and slow heart beats was also noted suggesting defective cardiac function and cardio-toxicity. Cytotoxicity was observed in all the treatments ranging from 40% to 90% mortality. The highest mean percentage mortality of 90% was recorded in 1250 ppm. Brine shrimp lethality assay showed an LC50 of 218.507 ppm, which indicates that the X. papulis ethanolic extract is highly toxic.