Analysis Of Bioactive Constituents In Bitter Melon

The antimicrobial activity of different Momordica charantia L. varieties against a series of bacteria and fungi were studied by using fresh and frozen-dried root, leaf and fruit juice as materials. The effect of some physical and chemical factors (pH, heat treatment and storage time) on antimicrobial efficacy of Momordica charantia L.was also studied in our test.' The results showed that fresh root and leaf juice had strong inhibitory effect on the common food-contaminated bacteria, as well as Staphylococcus aureus isolated from nosogenetic animal and human. The inhibitory effect of fresh leaf juice on Staphylococcus eipiceridis varied among different varieties. The fresh leaf juice did not show inhibitory effect on other bacterium and all fungi tested . The fresh root juice showed inhibitory effect on Escherichia coli, Klebsiella pneumonias and Escherichiu sakazakii isolated from nosogenetic human besides bacteria mentioned above, it could also inhibit the growth of Penicillium digitatum with the increase in dose, while fresh fruit juice did not show antimicrobial activity.The ten times concentrated root and leaf juice of 4 typical Momordica charantia L varieties had stronger inhibitory effect on the common food-contaminated bacteria and Staphylococcus aureus isolated from nosogenetic animal and human than control. On the contrary, the inhibitory activity of concentrated leaf juice on Staphylococcus eipiceridis reduced. At the same time, the inhibitory activity of concentrated root juice against Staphylococcus aureus and Staphylococcus eipiceridis which were isolated from nosogenetic human reduced or lost, while the inhibitory activity against Penicillium digitatum lost. The concentrated fruit juice showed antibacterial activity against common food-contaminated bacteria and Staphylococcus aureus isolated from nosogenetic animal.Antibacterial activity of heated leaf juice was almost as strong as fresh leaf juice, and after fresh root juice, frozen-dried leaf and fruit juice were heated, their antibacterial activities obviously reduced or lost.In addition, the bitter gourd is also characterized by its effective antimicrobialactivity at low minimum inhibitory concentration and wide pH range.SDS-PAGE and IEF analysis of water-soluble proteins were conducted in seeds of 4 typical Momordica charantia L varieties at different developmental stages, the results indicated that the seeds contained abundant water-soluble proteins within the molecular weight range from 14.4 to 116kD, including the 27.6,47.4 and 43.4kD protein with relatively high content, and three proteins whose molecular weight were roughly 30kD. There existed difference in the expression pattern of small molecular weight proteins among different varieties. The seeds contained at least 4 basic proteins in all varieties tested, while the difference existed in the content and the accumulation of the basic proteins among different varieties.