Extraction of total antioxidants from Azadirachta indica (neem) using three phase partitioning and its process intensification using ultrasound

The majority of the naturally occurring antioxidants are obtained from plant sources. The antioxidant activity is mostly exhibited by polyphenols present in the plant cells. Azadirachta Indica (Neem) leaves are renowned for their medicinal applications due to their anti-inflammatory, antimalarial, antifungal, antibacterial, antiviral, antioxidant, and anticarcinogenic properties. This work aims to optimize the extraction of Azadirachta Indica (Neem) leaf antioxidants using three-phase partitioning (TPP). The optimized conditions are operating time 15 minutes, slurry ratio 1:30 (g/mL), salt concentration 30% (w/v), aqueous to solvent ratio 1:1.5 (v/v), and stirring speed 400 rpm that infer 74.66% extraction yield. Additionally, ultrasonic pretreatment was also employed to increase the extraction yield up to 86.61%. Sonication pretreatment for 4 min operated at 30 W power, and 75% duty cycle was observed to offer maximum antioxidant extraction about 3.3 mg/g.