Characterization of organic acids, sugars, antioxidant and anti-inflammatory activities of <em>Citrus reticulate </em> Blanco cv. Nagpur

Abstract

The citrus fruits, commonly found in many regions of the world with a considerable number of species, have numerous beneficial effects, particularly for human health. The citrus organic acids and sugars play pivotal role in flavour and consumer acceptance of citrus fruit beverages. Here, some nutritive parameters related to the fruit <em>Citrus reticulate </em> Blanco cv. Nagpur (locally called santara) quality including sugars, organic acids, soluble solids, total acidity, and the content of bioactive compounds, such as phenolics and flavonoids were determined. The antioxidant and anti-inflammatory activities have been checked using <em>in vitro</em> assays. Four organic acids (citric, ascorbic, malic, and oxalic acids) and three sugars including glucose, sucrose, and fructose were determined. Citric acid was found as major organic acid whereas sucrose as major sugar in extracted orange juice and wine from this citrus fruit wine and juice. The HPLC quantification and analysis showed total 15 phenolic and flavonoid compounds including hydroxybenzoic acids, hydroxycinnamic acids, and flavanones in studied citrus juice and wine. The major phenolics and flavonoids found were ferulic acid, hesperidin, narirutin, and naringin in santara juice and wine. The santara juice showed significant antioxidant activity towards DPPH, FRAP, and H₂O₂ assays (IC₅₀±SEM [μg/mL]: 85.6±1.6, 60.2±1.6, and 35.5±1.1, respectively) and also exhibited greater inhibition towards lipoxidase (92.2%), β-glucuronidase (65.3%), hyaluronidase (48.1%), and diene-conjugates (40.6%) for anti-inflammation compared to orange wine. The high fruit quality of the studied citrus species indicates the importance of this fruit in human nutrition with prominent biological effects.