Evaluation of In vitro Anti-acne Activity and Formulation of Anti-acne Cream from Methanolic Extract of Nymphaea nouchali Pollens

Abstract

Acne vulgaris is a dermatological disorder. Although definite therapeutic agents are using in the treatment, herbal medicines are also still useful in the management of acne. The current study was designed to scientifically evaluate the anti-bacterial activity of Nymphaea nouchali pollens against Staphylococcus aureus and Staphylococcus epidermidis. The anti-bacterial activity of methanolic extract of N. nouchali pollens at seven different concentrations (244.14 μgmL-1, 488.28 μgmL-1, 976.56 μgmL-1, 1953.125 μgmL-1, 3906.25 μgmL-1, 7812.5 μgmL-1 and 15625 μgmL-1) were evaluated and IC50 values of N. nouchali pollens were determined. This was regarded as an anti-acne activity. Gentamicin was used as standard. Methanolic extract of N. nouchali pollens was incorporated considering the IC50 values of five different concentrations with eight different ratios consisting of oil, water, and surfactant to prepare emulsions with plant extract. Creams were prepared based on the most stable ratio for two groups, as non-homogenized and homogenized creams respectively. Creams were tested for anti-acne activity and pharmaceutical acceptance was evaluated by characterization and stability studies. The maximum anti-bacterial activity was observed in S. aureus and S. epidermidis at a concentration of 15625 μgmL-1. The most stable ratio for emulsion with plant extract was 35% w/w oil: 33% w/w water: 32% w/w surfactant. The highest anti-bacterial activity was shown in the homogenized cream with a concentration of 1% w/w. Creams are o/w types and all creams were thermodynamically and kinetically stable for 30 days at room temperature (28 ± 2 0C). Therefore, the results clearly indicate that 1% w/w homogenized cream formulation of N. nouchali pollens have a significant (p < 0.05) anti-acne activity against S. aureus and S. epidermidis.