Exploration of Pharmacological and Toxicological Properties of Aerial Parts of Blumea lacera, a Common Weed in Bangladesh

Abstract

Blumea lacera (Family Asteraceae) is a herb found in the uncultivated lands of many Asian countries. This plant is used by quack doctors for some medicinal purposes. Works presented in this manuscript were conducted on the ethanol extract of aerial parts of B. lacera. Various pharmacological tests like antioxidant, analgesic, anti-inflammatory, antidiarrheal, diuretic, antibacterial, anthelmintic and toxicological tests like brine shrimp lethality and acute toxicity were evaluated. Antioxidant test was conducted by determining secondary metabolites content and DPPH free radical scavenging assay. Acetic acid-induced writhing method, xylene-induced ear edema method, castor oil-induced diarrheal method, and urinary volume test were performed to evaluate the analgesic, anti-inflammatory, antidiarrheal and diuretic effects, respectively. The antibacterial test was performed by disk diffusion method, anthelmintic activity by recording the paralysis and death time of P. cervi and finally, cytotoxic activity was performed by brine shrimp lethality bioassay. TPC, TFC and TTC contents of B. lacera extract were found to be 9 mg GAE/g, 31 mg QE/g and 18 mg GAE/g. The SC50 value of the DPPH radical scavenging assay was found to be higher than 3000 µg·mL-1. The LD50 value of B. lacera extract in mice was higher than 5000 mg·kg-1. This extract significantly inhibited writhing reflexes by 24.5% and 43.6% and reduced ear edema up to 24.6% and 41% at 250 and 500 mg·kg-1 bw doses, respectively. It also increased the latency of the first defecation period up to 52.8 min and 106.6 min as well as decreased the stool count by 34.1% and 48.2% at 250 and 500 mg·kg-1 bw doses, respectively. It also showed an increase in urinary output in the diuretic test. Good antibacterial activity of B. lacera extract was confirmed by retardation in bacterial growth and significantly killed P. cervi in a dose-dependent manner. In brine shrimp lethality bioassay, the LC50 value was found to be 5.4 µg·mL-1. B. lacera showed mild analgesic, anti-inflammatory and antidiarrheal properties. It could be used as a diuretic, antibacterial, anthelmintic and cytotoxic drug which justify the plant's traditional uses in folk medicine.