Pharmacognostic standardization, phytochemical investigation and antioxidant studies on Phyllanthus reticulatus Poir.

Abstract

The present study describes the Pharmacognostic characters of Phyllanthus reticulatus Poir. (Family- Phyllanthaceae) for its precise identification and quality control of crude drugs procured from its leaf and stem bark through phytochemical screening along with analysis of antioxidant properties. P. reticulatus is an important plant that is used to treat oral diseases, diarrhea, muscular pain, asthma, conjunctivitis, and many other health problems. The macroscopic, microscopic and physicochemical evaluation of the crude drugs and other standardization methods recommended by WHO have been studied. Quantitative and qualitative analysis along with estimation of in-vitro antioxidant activity of therapeutically important selected phytochemical groups have also been performed. The Pharmacognostic study showed that the epidermal cells of abaxial and adaxial leaf surfaces are regular in shape and the cell walls are slightly wavy in outline. Stomata were anomocytic type with a stomatal index of 31.43±1.26% and palisade ratio of 10.83±0.12 and the leaves are of hypostomatic type. Only non-glandular, multicellular, and uniseriate trichomes were observed with trichome indices of 3.59±2.26% and 1.13±1.54% for both abaxial and adaxial leaf surfaces, respectively. Presence of glycosides, tannins, alkaloids, anthraquinones, saponins, etc. was noticed in the methanolic extracts of leaf and stem bark through microchemical colour reaction tests. The histochemical study revealed that the secondary phloem, cortex, cells of phelloderm and cork cells were the major localizing zones for different phytochemical groups. Total ash values of stem bark and leaf were 3.4% and 2.6%, respectively. Total phenolic content was found higher in stem brak (201.70±2.15mg GAE/g) than leaf (189.84±6.92mg GAE/g). Total tannin content in bark was 63.77±0.27mg of GAE /g and in leaf it was 41.55±0.57mg of GAE /g. The maximum content of alkaloids was measured in the leaf part (10.33±0.44 mg of PE/g) that is followed by stem bark (7.62±0.33 mg of PE/g). Total flavonoid contents of stem bark and leaf are 28.32±0.97mg of QE/g and 27.04±0.47 mg of QE/g, respectively. IC50 values of the methanolic extracts of leaf and stem bark in DPPH assay were estimated to be 41.27±0.48μg/ml and 33.54±0.54 μg/ml, respectively. IC50 values of the methanolic extracts of leaf and stem bark in ABTS radical scavenging assay were 37.02±0.033μg/ml and 31.27±0.51μg/ml, respectively. The Pharmacognostic including physicochemical profiles obtained through the present study may help in the identification, authentication, and establishment of a quality control standard of P. reticulatus. These findings also suggested that P. reticulatus is a good source of medicinally potent phytochemicals along with its promising antioxidant activity.