Evaluation of flavonoid composition and biological activities of hydrolyzed whole Pomelo Juice

Xi Xie¹Shanshan Zhuang¹Yanxia Gu²Yunrui Shen³Weisi Zhang⁴Lukai Ma¹Gengsheng Xiao¹Qin Wang¹Yonghui Zhong^5*Huifan Liu^1*

• ¹Zhongkai University of Agriculture and Engineering, Guangzhou, China
• ²Meixian, Institute of Agricultural Sciences, Meizhou, China
• ³Guangdong Dayue Mingzhu Agricultural Technology Co., LTD, Meizhou, China
• ⁴Guangdong Meizhou treasure golden pomelo industry Co., LTD, Meizhou, China
• ⁵Institute of Agricultural Sciences, Meixian, Meizhou, China

This study investigated the bioactive compounds as well as the antioxidant and anti-inflammatory properties of juice prepared from whole pomelo fruits (WPJ). The total flavonoid, naringin and nutrients contents in the WPJ during storage were determined, and the thirty-one flavonoid compounds were characterized by LC-MS. WPJ exhibited a high flavonoid content (950.68 ± 7.65 mg/100 g), primarily comprising hesperidin, tribuloside, baicalin, apigenin 7-O-neohesperidoside, hesperetin, neohesperidin dihydrochalcone, naringenin, naringin, jaceosidin, and pinocembrin. Dose–response experiments demonstrated that pretreatment with WPJ significantly reduced the levels of proinflammatory mediators, including nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α), in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. In a mouse model induced by phenol red, WPJ increased the secretion of phenol red in the respiratory tract of mice and inhibited their pulmonary inflammatory responses through MAPK/NF-κB signaling pathways. These findings suggested that WPJ may have beneficial effects on pulmonary health and may be useful as a functional food to prevent cough and phlegm related diseases.