Preliminary Phytochemical Analysis and In vitro Pharmacological Evaluation of Phytosterol rich fraction from Vetiveria zizanioides Nash

Abstract

Synthetic Steroids are well known for their analgesic and anti-inflammatory activity. Adverse effects of steroids include immunosuppression, skin decolouration, weakening of muscle, bone etc. Phytosterols exhibit better potency with less toxicity. In the present study, the synergistic effect of various phytoconstituents present in phytosterol rich fraction (SVZ) prepared from the root of Vetiveria zizanioides is evaluated for their pharmacological activities. Qualitative analysis of phytoconstituents and GC- MS analysis of SVZ was carried out. In vitro free radical scavenging by ABTS, DPPH scavenging assay, anti-diabetic activity by alpha-amylase and alpha- glucosidase inhibition assay and anti-inflammatory activity by HRBC membrane stabilization effect of SVZ were evaluated. The results reveal that SVZ is a rich source of macromolecules like carbohydrate, fixed oil and fat. Alkaloids, phenols are observed to be absent in SVZ. GC-MS spectra show the presence of 24 phytoconstituents. Most of them are sterols and they are present in association with other bioactive compounds like aromadendrene oxide-1, n-hexadecanoic acid etc., The sterol-rich fraction exhibits scavenging potency of free radicals like ABTS, DPPH and NO with IC50 value at 112.34, 171.2, 95.4 µg respectively. SVZ inhibits 50% of α- amylase and α- glucosidase at 425.5 and 453.3 µg. The IC50 value of SVZ against HRBC membrane stabilization was calculated as 59.6 µg. A significant difference has not been observed between SVZ and ascorbic acid in free radical scavenging activity. SVZ exhibits HRBC membrane stabilizing activity similar to that of paracetamol. In conclusion, SVZ is a rich source of phytosterol with potent antioxidant, anti-inflammatory activity. Anti-diabetic activity of SVZ should be evaluated further.