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The antimicrobial activities of the methanolic extracts of Euphorbia hirta Lleaves, flowers, stems and roots were evaluated against some medically important bacteria and yeast using the agar disc diffusion method. Four Gram positive (Staphylococcus aureus, Micrococcus sp., Bacillus subtilis and Bacillus thuringensis), four Gram negative (Escherichia coli, Klebsiella pneumonia, Salmonella typhi and P. mirabilis) and one yeast (Candida albicans) species were screened. Inhibition zones ranged between 16–29 mm. Leaves extract inhibited the growth of all tested microorganisms with large zones of inhibition, followed by that of flowers, which also inhibited all the bacteria except C. albicans. The most susceptible microbes to all extracts were S. aureus and Micrococcus sp. Root extract displayed larger inhibition zones against Gram positive bacteria than Gram negative bacteria and had larger inhibition zones compared to stem extract. The lowest MIC values were obtained with E. coli and C. albicans (3.12 mg/mL), followed by S. aureus (12.50 mg/mL) and P. mirabilis (50.00 mg/mL). All the other bacteria had MIC values of 100.00 mg/mL. Scanning Electron Microscopic (SEM) studies revealed that the cells exposed to leaf extract displayed a rough surface with multiple blends and invaginations which increased with increasing time of treatment, and cells exposed to leaf extract for 36 h showed the most damage, with abundant surface cracks which may be related to final cell collapse and loss of function. Time-kill assay of C. albicans indicated a primarily fungicidal effect at 1- and 2-fold MIC. E. hirta extracts had LC50 values of 0.71, 0.66, 0.41 and 0.03 mg/mL for stems, leaves, roots and flowers, respectively against Artemia salina. Hence, these plants can be used to discover new bioactive natural products that may serve as leads in the development of new pharmaceuticals.

Background: The objective of this study was to investigate the antioxidant and hepatoprotective effects of methanolic extracts of L. edodes and the determination of their total phenolics content. Results: The amount of total phenolics was estimated to be 70.83 mg Gallic Acid Equivalent (GAE) per gram of dry extract. The antioxidant activity of the L. edodes extract was 39.0% at a concentration of 1 mg/mL and was also concentration dependant, with an EC50 value of 4.4 mg/mL. Different groups of animals (Wister albino mice) were administered paracetamol (1 g/kg, p.o.). L. edodes extract at a dose of 200 mg/kg was administered to the paracetamol treated mice for seven days. The effects of L. edodes extract on serum transaminases (SGOT, SGPT), alkaline phosphatase (ALP) and bilirubin were measured in the paracetamol-induced hepatotoxic mice. L. edodes extract produced significant (p < 0.05) hepatoprotective effects by decreasing the activity of serum enzymes and bilirubin. Conclusion: From these results, it was suggested that L. edodes extract could perhaps protect liver cells from paracetamol-induced liver damage by its antioxidative effect on hepatocytes, hence diminishing or eliminating the harmful effects of toxic metabolites of paracetamol.