Quantification of bioactive compounds in guava at different ripening stages

Abstract

Guava (Psidium guajava L.) is one of the most important tropical fruits belonging to the genus Psidium and the Myrtaceae family and claim to have phenolic compounds that have been reported to possess strong antioxidant activity. This study was aimed to evaluate the bioactive constituents in guava cultivars at different ripening stages by HPLC. The five guava cultivars were selected at different ripening stages and the bioactive components were analysed by high-pressure liquid chromatography. The quantification of bioactive compounds revealed that the highest amount of bioactive compounds was found in cultivar Safeda at the unripe stage, while a minimum amount was found in ripe Apple Colour guava cultivar. The six bioactive compounds were quantified in the range of gallic acid (9.46-63.08 mg/100 g), quercetin (0.11-2.51 mg/100 g), myrcetin (0.09-0.034 mg/100 g), ascorbic acid (7.45-75.07 mg/100 g), apegenin (0.01-0.032 mg/100 g) and lycopene (0.34-0.92 mg/100 g). The exploratory evaluation of guava samples was performed through Principal Component Analysis (PCA), the bioactive compounds, lycopene, myricetin, and quercetin are dominant variables on this PC1 (61.52%) (Scores better than 0.7), thereby causing greater variability among these samples. The second principal component (PC2) represents 16.54% of the total variance and the ascorbic acid, gallic acid and apeginin (score better than 0.7), are the dominant variables on this PC.