Screening of successive extracts of <i>Amorphophallus konjac</i> for antibacterial activity

Abstract

Amorphophallus is an Aroid family member, native to Asia. Amorphophallus konjac K. Koch ex N.E.Br. is also known as snake plant due to snake like outlines on its stem. In Mount Abu the plant is grown in wild and known for its toxic principles. In Traditional Chinese System of Medicine (TCM), it was mentioned that gel prepared from flour has been used in detoxification, tumor suppression, phlegm liquefaction and skin disorders. In the present research work, attempts were made to authenticate and validate the ethno-medicinal potentials of A. konjac antimicrobial activity which could be alternate for current synthetic antimicrobial agents. The plant was selected for screening of antimicrobial efficacy against eight selected bacterial strains viz. Staphylococcus aureus (ATCC- 2921), Klebsiella pneumoniae (ATCC 700603), Enterobacter cloacae (ATCC 13047 ), Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Proteus mirabilis (ATCC  12453), Enterobacter cloacae (ATCC- 13047), Enterococcus faecalis (ATCC 29212) and Streptococcus pneumoniae (ATCC 6305). The results of antimicrobial activity of crude dicholormethane (DCM), ethyl acetate, chloroform and methanol were significant. DCM extract C (10 mg/disc) possess maximum efficacy against S. pneumoniae (IZ = 20 mm; AI = 1.25). The main cause of community acquired pneumonia and septicemia in HIV infected patients is caused by S. pneumoniae microorganism. Further, bioactivity guided fractionation of pure compounds from DCM extract of A. konjac can lead to work as novel antibiotic in future. Therefore, the extract can also be used for isolation of volatiles compounds with potentials so that the extract / active fraction / pure compounds can be used as nasal spray in future therapeutics.

Key words: Amorphophallus konjac, antibacterial activity, antimicrobial agents, ethnomedicinal plant.