Exploring Drosophila melanogaster as a model for assessment of antioxidant potential of Rauvolfia serpentina

Background: The well-known Apocynaceae herb Rauvolfia serpentina is praised for its many pharmacological qualities, which include antibacterial, antifungal, anti-inflammatory, and anti-proliferative capabilities. Its antioxidant action has been proven in vitro, but there isn't any proof of its impact in vivo. Method:  The total antioxidant capacity, ABTS radical scavenging capacity, flavonoid content, total phenolic content, and FRAP value of Rauvolfia serpentina mother tincture (RS MT), as well as its selected potencies (30C, 200 C) were examined in vitro.  Adult Drosophila melanogaster were exposed to RS MT, RS 30C and RS 200C (10 µL dose was calculated as per the homeopathic prescription) either with or without 15 mM paraquat (PQ) for 24 hours. For in vivo analysis, five groups of D. melanogaster were organized for the experiment: (1) Control; (2) PQ; (3) PQ + RS MT; (4) PQ + RS 30C; and (5) PQ + RS 200C. Three repetitions of each experiment were conducted at different time intervals. Result: According to in vitro data, RS MT had a greater phenolic and flavonoid content. Additionally, all three preparations had notable radical scavenging potential. Interestingly, RS 30C showed increased ABTS scavenging potential and FRAP value despite low phenolic and flavonoid content. Upon PQ co-exposure, RS 30C significantly increased catalase and SOD activity, while decreasing GST activity and LPO levels. The total oxidative stress (NBT levels) was also significantly reduced by the RS 30C. RS 200C rescued the altered metabolic activity due to PQ. Conclusion: This study confirms that R. serpentina (RS MT, RS 30C and RS 200C) reduces oxidative stress and scavenges free radicals by assessing its antioxidant properties in both in vitro and in vivo studies. Further it confirms that RS at 30C showed greater effectiveness compared to 200C and MT by preventing paraquat-induced oxidative stress. D. melanogaster has proven to be the most reliable and effective in vivo model for investigative antioxidant properties, highlighting its value for further research in this field.