Antioxidative, phytochemical and antimicrobial analysis of juices of eight citrus cultivars grown in Pakistan

Comparative nutritional analysis of citrus varieties cultivated in Pakistan has not been reported. Citrus is consumed all over the world due to its taste and also has pharmacological components. The present investigation evaluated the antioxidant, reducing power, total flavonoids and phenolics, DPPH free radical scavenging, protein kinase inhibition, and the antimicrobial activities of eight Pakistani citrus varieties. Grapefruit showed maximum total antioxidant potential (77 µg AAE/100 mg), followed by Kinnow and Shakri. Khatai showed maximum reducing power potential (69.6 µg AAE/100 mg) while Shakri and Grapefruit trailed it. All the varieties showed significant DPPH free radical scavenging activity. Maximum total phenolics in citrus juice were found in Shakri and Kinnow; 26.2 and 25.9 µg GAE/100mg, respectively. Variation in total flavonoids content was observed as Kinnow>Grapefruit>Shakri>Khatai. All the citrus juices showed mild to moderate antibacterial activity, while Mosambi and Malta contained potent antifungal components. HPLC analysis of citrus juices revealed that catechin was present in all citrus genotypes except Kinnow. The study concludes that citrus juices contain strong antioxidative potential, bear protein kinase inhibitors and can be used as cancer chemoprevention and supportive nutrition.