CONVENTIONAL AND NON-CONVENTIONAL TECHNIQUES FOR EXTRACTION OF FLAVONOIDS FROM SELECTED PLANTS

Medicinal plants are enriched with biological substances that are proven to be a direct or indirect source of modern drugs. The relevance of the exploration of new natural reservoirs of pharmaceutical potential has increased immensely after COVID-19. The present study deals with the extraction of flavonoids from selected plants i.e.  Ricinus communis, Euphorbia hirta and Croton bonplandinum from the family Euporbiaceae by following conventional and non-conventional techniques. The conventional and non-conventional method includes Soxhlet extraction and Ultrasonic Assisted Extraction, respectively. Significant and comparable results were obtained for the ultrasonic technique in terms of the total quantity of extracts. The quantity of total flavonoid extract from the root, stem of Ricinus communis and stem, fruit, and root of croton bonplandinum is much greater in UAE (4.8mg/gdw and 36.9mg/gdw, respectively; 8.9mg/gdw, 60.5 g/gdw, 10.7 mg/gdw respectively) than Soxhlet method (0.95 mg/gdw and 4.8 mg/gdw respectively; 0.99 mg/gdw, 13.54 mg/gdw and 1.29 mg/gdw, respectively). The higher quantity of total flavonoids was recorded to be more for all extracts of Euphorbia hirta by the Soxhlet technique than the UAE method. The present investigation advocates the use of UAE as a regular extraction technique as it consumes less amount of solvent and plant sample than the Soxhlet technique. Moreover, it has been found more efficient and flexible in terms of time management and easy regulation of the protocol. The major constraint of Soxhlet extraction is the exorbitant use of solvent and time, whereas UAE offers reasonable and economical utilization of time and solvent.