Comparative Phytochemical and Antimicrobial Study of Ultrasound-Assisted Aqueous Extract from Fresh Plants of Bryophyllum pinnatum with Conventional Extraction Method

Abstract

Bryophyllum pinnatum is a potential medicinal plant widely used in different tribes in Bangladesh. The leaves of B. pinnatum were used in the present study for the compatibility assessment of a proposed ultrasound-assisted green extraction method with the conventional extraction method. An aqueous Ultrasound-Assisted Extraction (UAE) by using both fresh and dried leaves of B. pinnatum was proposed in the present study and successively compared with the traditional methanolic and aqueous (decoction) extraction method. The promising extraction yield was found through the proposed extraction method which was much better than decoction and almost similar to the methanolic extraction method. Phytochemical contents were also observed similar to the methanolic extract. Both methanolic and UAE extracts obtained from B. pinnatum leaves showed favorable antimicrobial sensitivity against both grams positive (Staphylococcus aureus and Streptococcus pyogenes) and gram-negative (Escherichia coli and Salmonella typhi) bacteria. Extracts obtained from the decoction method showed slightly poor antimicrobial activities. The difference in efficiency and efficacy of aqueous UAE extract obtained from fresh and dried leaves was observed insignificant. This indicates there is no necessity to impart the drying stage before extraction normally practiced in the conventional extraction method. Drying of plant material is a common stage of the conventional extraction cycle which ultimately lengthy the process and impose cost due to energy consumption and labor. Ultrasound-assisted extraction may successfully decrease the overall extraction cycle and ultimately reduce the overall cost of extraction. This method also creates opportunities to replace the water instead of with hazardous organic solvent for phytochemical extraction.