Comparative study of antimicrobial activities of Aloe vera extracts and antibiotics against isolates from skin infections

Abstract

Plants are of relevance to dermatology for both their beneficial and adverse effects on skin and skin disorders. One of the medicinal plants, Aloe vera (Aloe barbadensis Miller), is reputed to have medicinal properties. For centuries, it has been used for an array of ailments such as mild fever, wounds and burns, gastrointestinal disorders, diabetes, sexual vitality and fertility problems to cancer, immune modulation, AIDS and various skin diseases. In this study, antibacterial activity of leaf and gel extracts of A. vera were tested against gram positive and gram negative skin infections isolates. For this purpose, one hundred and fifteen bacterial strains were isolated from skin wounds, burns and acne patients from various hospitals of Karachi, a cosmopolitan and heavily populated city of Pakistan, and the strains were identified by conventional methods. Among the total isolates, 90% of the organisms were gram positive while the remaining 10% were gram negative. The gel extracts of A. vera showed antibacterial activity against both gram positive and gram negative isolates while the leaf extracts showed no such activity. In parallel, five standard antibiotics were also tested against the isolated strains. The data showed promising results in case of A. vera compared to five broad-spectrum antibiotics. Additionally, the study also demonstrated that the skin infectious isolates were resistant against broad-spectrum antibiotics.

Key words: Aloe vera, antimicrobial, antibiotics, skin infections, Karachi.