Impact of microwaves on the extraction yield of phenolics, flavonoids, and triterpenoids from centella leaves: An approach toward digitized robust botanical extraction

Introduction: A novel green approach of microwave-based extraction of botanicals for improved yield of bioactives has been investigated. In this regard, leaves of Centella asiatica which has a rich history of ethomedicinal use were chosen. Objective: The aim of this study is to develop a robust optimized microwave-based extraction protocol for improved yield of phenolics, flavonoids, and triterpenoids principles. Materials and Methods: Microwave power and extraction time were critically optimized along with the effect of moisture content through sample pretreatment. Effect of optimized operating conditions on the biological integrity of the extract and on the extraction of other nutraceutical principles was also evaluated. Results were compared to traditional extraction methods. Results: The final optimum extraction conditions were 50% microwave power, 6-min irradiation time, and 54% moisture content for maximum yield of phenolics and triterpenoids, whereas for flavonoids, optimum microwave power was 40% with other conditions remaining same. The proposed method was found to be three-fold better than 36 h of Soxhlet extraction and produced 200 times lesser carbon load than Soxhlet. Improved yield of other nutraceutical principles with better anti-oxidant activity was recorded for the proposed method. Conclusion: Switching to such greener technology is now the need of the hour. This research is a sincere effort to showcase the potential of green chemistry in the herbal drug industry.