Antimicrobial activity of the lupane triterpene 3ß,6ß,16ß-trihydroxylup-20(29)-ene isolated from Combretum leprosum Mart.

Introduction. Combretum leprosum (Combretaceae) is commonly found in the Northeast Region of Brazil and is known for several bioactivities, including antimicrobial ones. Because of increasing bacterial antibiotic resistance, natural products from several plants have been studied as putative adjuvants to antibiotic activity, including products from C. leprosum. Aims. This study was carried out to investigate the structural properties, bactericidal activity and antibiotic modifying action of the lupane triterpene 3ß,6ß,16ß-trihydroxylup-20(29)-ene (CLF1) isolated from C. leprosum Mart. leaves.Methods. The CLF1 was evaluated by the Fourier transform infrared spectroscopy method and the antibacterial activity of this compound was assayed alone and in association with antibiotics by microdilution assay.Results. Spectroscopic studies confirmed the molecular structure of the CLF1 and permitted assignment of the main infrared bands of this natural product. Microbiological assays showed that this lupane triterpene possesses antibacterial action with clinical relevance against Staphylococcus aureus. The CLF1 triterpene increased antimicrobial activity against the multidrug-resistant Escherichia coli 06 strain when associated with the antibiotics gentamicin and amikacin. Synergistic effects were observed against the S. aureus 10 strain in the presence of the CLF1 triterpene with the antibiotic gentamicin.Conclusion. In conclusion, the CLF1 compound may be useful in the development of antibacterial drugs against the aforementioned bacteria.

The pattern of bacterial isolates and drug sensitivities of infected ulcers in patients with leprosy in ALERT, Kuyera and Gambo hospitals, Ethiopia.

INTRODUCTION: Leprosy remains a public health problem, mainly in Africa, Asia and Latin America. Leprosy has many complications that include leprosy reactions, development of plantar and hand ulcerations, lagophthalomus and corneal anesthesia. OBJECTIVES: In Ethiopia there is scarce information on the pattern of bacterial isolates and drug sensitivities of infected ulcers in patients with leprosy. This study was undertaken to identify the bacteriology of infected ulcers and to determine their antimicrobial susceptibility pattern. STUDY DESIGN: A descriptive cross-sectional study was conducted in 245 informed and consented leprosy patients with infected ulcers visiting ALERT, Kuyera and Gambo hospitals during the period August 2006 to May 2007. MATERIAL AND METHODS: Wound aspirate specimens were collected from ulcers of each patient aseptically and inoculated into standard bacteriological media. Antimicrobial susceptibility testing was performed for all isolates according to the criteria of the National Committee for Clinical Laboratory Standards (NCCLS) by disk diffusion method. RESULTS: Of the 245 patients investigated, 64.1% were males and 35.9% females (P < 0.05). The average age of the patients was 50 years (age range 13 to 92 years). According to Ridley-Jopling classifications, patients presented with TT (3.7%), BT, (31.4%), BL (44.5%) and LL (15.9%) types of leprosy. Plantar and hand ulcers were observed in 92.2% and 7.8% of patients, respectively. According the patients, the commonest cause of their ulcers was 'spontaneous' (56.7%). There were 44% Gram-positive and 56% Gram negative bacteria (P > 0.05). Proteus spp. accounted for 29.5% of the total isolates followed by Staphylococcus spp. (28.8%), beta-hemolytic streptococci (15.1%) and different types of Gram-negative bacteria (26.2%). Multiple organisms (two or three) were isolated from 19.6% patients. Of the 212 wound samples cultured anaerobically, 5.2% were positive for anaerobic culture. In this study both Gram-positive and Gram negative bacteria showed decreased sensitivity to most antimicrobial agents tested. CONCLUSION: Proteus spp. was the most common isolate from infected ulcers. Ciprofloxacin, norfloxacin and gentamicin were the most effective drugs against the tested bacteria mainly for Gram-negative bacteria. This refers to the in vitro-sensitivity during the study period. The results of this study may help inform clinicians about the selection of an antibiotic in situations where use of an antibiotic may be indicated.