Abstract

ASSESSMENT OF THE ANTIOXIDANT ACTIVITY AND PHYTOCHEMICAL ANALYSIS OF A LICHEN, EVERNIASTRUM CIRRHATUM (FR.) HALE ex. SIPMAN

Anil Khushalrao Shendge, Tapasree Basu, Gopal Prasad Sinha, Nripendranath Mandal*

ABSTRACT

Free radicals generated in system induce oxidative stress related diseases. Recent research is focused on plants and phytocompounds to avoid various side effects. The present study is aimed to evaluate the free radical scavenging potential along with phytochemical screening of the 70% methanolic extract of a lichen, Everniastrum cirrhatum (Fr.) Hale (ECME). ECME was tested for its in vitro total antioxidant capacities and various other reactive oxygen and nitrogen species (ROS, RNS) scavenging potentials. For further insight, phytochemical screening through qualitative and quantitative analyses along with HPLC standardization were performed. It was observed that ECME showed total antioxidant capacity with TEAC value of 0.384 ± 0.0074 as compared to Trolox. The lichen also showed excellent ROS and RNS scavenging capacities as it scavenges hydroxyl, superoxide, hypochlorous acid, nitric oxide and peroxynitrite radicals with IC50 values of 208.09 ± 6.36, 142.26 ± 3.17, 150.07 ± 3.01, 118.19 ± 5.99 and 3037.07 ± 222.43 μg/ml respectively. Singlet oxygen is also scavenged but to a lesser extent by ECME. Phytochemical analyses of ECME showed greater presence of alkaloids, phenolics, flavonoids like compounds as compared to other phytocompounds. Moreover HPLC analysis of ECME revealed the presence of antioxidant phytochemicals like purpurin, usnic acid, tannic acid, reserpine and rutin at various retention times. The in vitro results show that ECME possesses promising antioxidant and free radical scavenging potentials and hence this lichen can be further explored for various phytocompounds against oxidative stress.

Keywords: Lichen, Antioxidant, Hydroxyl radical, HPLC, Usnic acid.