**7. Antimicrobial activity**

*M. charantia* extract has been suggested to have broad-spectrum antimicrobial activity, clinical signs of broad-spectrum antimicrobial activity has been delivered by the extract of bitter melon leaf [25]. Polysaccharides isolated from *M. charantia* have been reported to have significant inhibitory effects on bacteria. It has been shown that the main components of *M. charantia* responsible for antimicrobial functions are polysaccharides [26]. It is also suggested that antibacterial properties of *M. charantia* oil is related to its high trans-nerolidol and conjugated linolenic acids content [25, 26]. *M. charantia* is a basis of natural products which derived from plant with antimicrobial activity. A component of bitter melon, α-momorcharin, due to its ribosome-inactivating protein (RIP) ability is effectual in inhibiting the fungal and bacterial growth [25, 26, 30]. It has been reported that *M. charantia* polysaccharides have a good bacteriosis activity in *B. subtilis*, *S. aureus*, *S. typhimurium* and *E. coli* and the most obvious effect is the effect on *S. aureus* [26]. Essential oils of *M. charantia* seeds have significant inhibitory effect on *S. aureus*, while having less impact on *E. coli* and *C. albicans* [26, 30]. It has been demonstrated that the whole plant extract has antiprotozoal activity and methanol, water, and ethanol extract of the bitter melon leaves are considered to have an antibacterial action against *Salmonella, Pseudomonas aeruginosa, E. coli, Bacillus*, and *Streptococcus* chain [26, 30]. *M. charantia* fruit also has an anti-*Helicobacter pylori* activity that is a causal agent of ulcer [26, 30].
