Effects of Jatropha curcas Linn and Nicotiana tabpacum Linn on Antibiotic-Resistant Isolates from Wounds of Diabetic Patients

Abstract

Investigations were conducted to determine the effects of Jatropha curcas Linn and Nicotiana tabacum Linn on antibiotic resistance isolates from wounds of diabetic and non-diabetic patients attending government hospitals in Ondo State. A total of 454 wound swab samples were screened to determine the microbial types and loads using growth-dependent and molecular methods. The antibiotic susceptibility patterns of the isolates were determined, after which isolates that showed multiple antibiotic resistance were exposed to different concentrations of extracts from J. curcas and N. tabacum. Extracts were prepared from different parts (stem, seed, leaf, shaft and root) of N. tabacum and J. curcas using cold water, hot water (100oC), ethanol and n-Hexane as the extraction solvents, at concentrations of 25, 50, 75 and 100% (w/v). The phytochemical investigation of the crude extract of various parts of the plant was carried out using standard techniques. The in-vivo study on therapeutic and biosafety effects of the extracts in Wistar albino rats were carried out using standard technique. Generally, the antimicrobial potential of the extracts increased with a corresponding increase in extract concentration. The antimicrobial efficacy of the plant extracts depended greatly on the extract concentration, type of test plant, test isolate, and the extraction solvent. Proteus vulgaris and Escherichia coli were the most susceptible to ethanolic root extracts (75% w/v concentration) of Jatropha. curcas with 12.00±0.62 mm and 11.50±0.57 mm diameter of the zones of inhibition. Jatropha curcas ethanolic leaf extracts (75% w/v concentration) was most effective against P. aeruginosa with 12.00±0.33 mm diameter of the zone of inhibition, whereas P. aeruginosa was least susceptible to n-hexane extracts (75% w/v concentration) with 5.20±0.33 mm diameter of the zone of inhibition. Quantitative phytochemical screening revealed the highest amount of saponins and flavonoids in J. curcas, while N. tabacum had the highest concentration of alkaloids. The major bioactive compounds in N. tabacum were Limonene, phenols and esters; while Squalene, Octadecyne andesters were the major bioactive compounds in J. curcas. Microbiological assay revealed that S. aureus, P. aeruginosa and C. albicans were the most frequently encountered microorganisms. Antimicrobial assay revealed that ethanolic (75% v/w concentration) and hot water extracts of the seed and leaf of J. curcas and N. tabacum extract had the most remarkable antimicrobial activity among the extraction solvents. Ethanol rated best as the extraction solvent, followed by hot water, n- hexane and cold water in that order. The findings revealed that hot water leaf extracts of J. curcas and N. tabacum administered on Wistar albino rats enhanced the weight and increase in the level of haematological parameters compared with ethanolic seed extracts. Jatropha curcas extracts show significant effects than N. tabacum extracts in enhancing the tested biochemical parameters except in the level of uric acid but indicate reduced level of tested enzyme markers. The biosafety concentration of the extracts at the dose of 1.00 ml of 10g/100ml established and were not lethal even at 1.50ml. Antimicrobial efficacy and biosafety evaluation of J. curcas and N. tabacum had been proven to be potent against the microbial effects in wounds treatment.