U. wallichiana is found in Uttarakhand in India, and its bark is often used as a traditional remedy for bone fractures in both humans and animals, as well as to heal wounds.
Based on this, researchers from the Sardar Bhagwan Singh Post Graduate Institute of Biomedical Sciences & Research designed a study to investigate the antimicrobial potential of different U. wallichiana bark extracts.
Plant versus bacteria
They collected the plant bark and pulverised it to obtain a powder, which they then used to prepare the different extracts to be tested: petroleum either, chloroform, ethyl acetate, ethanol, and aqueous.
They subsequently found that the ethyl acetate extract "exhibited the highest significant antioxidant activity".
The extract exhibited antibacterial activity against the bacteria Escherichia coli, Bacillus subtilis, Staphylococcus aureus and Pseudomonas aeruginosa.
Compared to the rest of the extracts, it also displayed a superior zone of inhibition against the aforementioned bacteria.
While the chloroform extract had a moderate inhibition zone against the bacteria, the ethyl acetate extract's inhibition zone was better than that of the standard drug chloramphenicol, an antibiotic used to treat bacterial infections.
Fighting the fungus
The different extracts' antifungal properties were also tested against Aspergillus flavus and Aspergillus fumigates.
Once more, the researchers observed that among all the extracts, the ethyl acetate extract displayed the maximum inhibition zone.
The chloroform extract exhibited mild antifungal activity, while the ethyl acetate extract's antifungal activity was comparable to that of the antifungal medication nystatin.
Isolation needed
The researchers stated that the ethyl acetate extract of U. wallichiana exhibited the strongest antimicrobial properties, and as such, "should be further investigated for isolating active compound(s) responsible for antimicrobial activity".
They added that the "phytochemical screening of ethyl acetate extract indicated the presence of mainly phenolic and flavonoid compounds", saying that these active constituents might be behind U. wallichiana's antimicrobial properties.
They concluded: "Based on the findings of this study, future prospects of the current investigations suggested that ethyl acetate extract of the plant should be further analysed to isolate the specific antimicrobial principle(s) present in the plant."
Source: Journal of Ayurveda and Integrative Medicine
http://dx.doi.org/10.1016/j.jaim.2017.02.009
"Evaluation of antimicrobial potential of successive extracts of Ulmus wallichiana Planch"
Authors: Kundan Singh Bora, et al.