ABSTRACT
Objective: To evaluate the antibacterial activity of the hydroalcoholic and ethanolic extracts of the Usnea longissima lichen. Material and methods: Kirby Bauer's disk diffusion method and broth serial dilution tests according to CLSI Guidelines (2000) were used, to find out the antibacterial effect of the 50% Hydro-ethanolic and 90% ethanolic extracts of the selected lichen. The efficacy of the extracts were measured after the period of incubation as Zone of Inhibition (ZOI) in mm compared with the Standard drug used i.e. Ciprofloxacin for Gram positive and Gentamicin for Gram negative bacterial strains. MIC was further tested for susceptible organisms. DMSO was used as control. All the experiments were conducted in triplicates and in proper sterilized condition Results: It was found that Usnea longissima has a significant activity towards Bacillus cereus (ZOI 25-26 mm as compared to Ciprofloxacin ZOI-23 mm) MIC-0.625 mg/ml, Pseudomonas aeruginosa (ZOI 20-27 mm as compared to Gentamicin ZOI-14 mm) MIC- 1.25 mg/ml and Proteus vulgaris (ZOI of 13 - 16 mm where as Gentamicin produced ZOI as 14 mm) MIC 2.5 mg/ml. Moderate activity was shown towards Staphylococcus aureus, Corynebacterium xerosis, Escherichia coli and Klebseilla pneuomoniae while no activity towards S. epidermidis and S. pyrogenes. Moreover it was seen that 50% Hydro-ethanolic extracts produced more significant ZOI than ethanolic extract in all tested strains. Conclusions: U. longissima contains potent chemical constituents as Usnic acid which can halt infection and is effective against various gram-positive and gram-negative bacterial species. It can be concluded that due to their antimicrobial effects extracts of the lichen can be used for the infectious diseases caused by these microbes. This study provides an in-vitro proof of the antibacterial activity of Usnea longissima.
ABSTRACT
Dietary agents including spices, vegetables and fruits have drawn a great deal of attention from both the science peoples and the general public due to their various health promoting effects, these agents consist of a wide variety of biologically active compounds, many of them have been used as traditional medicines from thousands of years. Zingiber officinale commonly known as ginger is one of the most widely used species of the ginger family, commonly used as a condiment for various foods and beverages. It has a long history of medicinal use dating back 2500 years. Ginger is well known all over the world especially for its use in disorders of the gastrointestinal tract such as constipation, dyspepsia, diarrhoea, nausea and vomiting. Ginger is described by Dioscorides as hot, digestive, gently laxative and stomachic. This article aims at reviewing the Zingiber officinale on the basis of Traditional system of Medicine and to discuss its recent Phytochemical and Pharmacological studies.