Shelf-Life Extension of Tomato （Lycopersicum esculentum） and Pepper （Capsicum annuum） Using Aqueous Extracts of Some Ethnomedicinal Plants

This research aimed at the use of natural products to extend the shelf life of perishable vegetables. Studies were conducted on the preservative effects of four plant extracts--Xylopia aethiopica, Piper nigrum, Tetrapleura tetraptera and Carica papaya seeds on tomato and pepper. Tomato and pepper were dipped into four different concentrations of aqueous extracts of the four plants as well as water serving as control. The result of the study showed that aqueous extract of all plants extended the shelf life of tomato and pepper with increasing concentration of the extracts, except for Carica papaya seeds which produced significant elongation of 12.0 ±0.6 d and 14.0 ± 0.7 d on tomato and pepper, respectively, at the least concentration of 0.25 mg/mL. The results showed that these ethnomedicinal plants can serve as good and potent sources of natural preservatives which can be used to substitute existing synthetics used in the food industry.

Antibacterial efficacy of five medicinal plants against multidrug-resistant enteropathogenic bacteria infecting under-5 hospitalized children

OBJECTIVE： To evaluate in vitro antibacterial effectiveness of five medicinal plants used by an Indian aborigine, against 8 multidrug-resistant （MDR） enteropathogenic bacteria isolated from clinical samples of under-5 hospitalized children. METHODS： Antibiotic sensitivity patterns of eight clinically isolated strains of enteropathogenic bacteria, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, Salmonella paratyphi, S. typhi, Shigella dysenteriae, S. sonnei and Vibrio cholerae were assessed by disc-diffusion method. Antibacterial activities of 8 solvent-extracts of leaves and bark of five medicinal plants were monitored by the agar-well diffusion method. The microbroth dilution method was used to assess minimum inhibitory concentration （MIC） and minimum bactericidal concentration （MBC）. Qualitative phytochemical analyses of active plant extracts were carried out. RESULTS： Ethanol, ethyl acetate and methanol extracts of Holarrhena antidysenterica leaf tissue were most effective against 8 MDR pathogens in vitro. Similarly, acetone, ethanol and methanol extracts of Terminalia alata leaf tissue; chloroform, ethyl acetate and methanol extracts of Terminalia aquna leaf tissue and ethyl acetate, ethanol and methanol extracts of Paederia foetida leaf tissue were most effective in inhibiting in vitro growth of the 8 MDR enteropathogens. Ethyl acetate and methanol extracts of H. antidysenterica bark tissue; acetone, ethanol and methanol extracts of T. alata bark tissue and acetone, ethanol and methanol extracts of T. arjuna bark tissue were most effective in controlling enteropathogen growth. The minimum inhibitory concentration and minimum bactericidal concentration values of the 3 most antimicrobial leaf and bark extracts from the five plants were in the range of 1.56 to 50 mg/mL. CONCLUSION： These 5 plants exhibited in vitro control over a cohort of 8 enteropathogenic bacteria strains isolated from clinical samples.