Proximate analysis and antioxidant activities of four popular Chinese Lamiaceae herbs in Malaysia

Abstract

Chinese herbal plants are known to be among the promising sources of variety of essential nutrients and antioxidant constituents. The objective of this study was to evaluate four Chinese herbs from the family of Lamiaceae which are popular in Malaysia; Plectranthus amboinicus, Vitex negundo, Salvia miltiorrhiza and Scutellaria baicalensis, on their proximate compositions, total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activities; DPPH and FRAP assays. Results showed that these herbs were relatively significant different from each other for their proximate compositions, TPC, TFC and antioxidant activities. Apparently, P. amboinicus has higher levels of ash (21.46±0.16%) and dietary fibre (41.24±1.25%) while V. negundo contained the highest crude fibre (19.41±1.98%) than the rest of the samples. Salvia miltiorrhiza consisted of high TPC (105.90±3.37 mg GAE/g), TFC (241.55±55.15 mg QE/g), DPPH radical scavenging activities (IC50: 169.10±14.17 µg/mL) and FRAP (103.09±2.84 µg FeSO4/g). Overall, the imported herb of S. miltiorrhiza is a potent natural antioxidant source with extremely low fat content to fight against oxidative stress and reactive oxygen species. More studies on the Lamiaceae family plant should be performed to determine more potential bioactivity which is beneficial to human health.