Mary H. Grace, Debora Esposito, Michael A. Timmers, Jia Xiong, Gad Yousef, Slavko Komarnytsky, Mary Ann Lila (2016). Chemical composition, antioxidant and anti-inflammatory properties of pistachio hull extracts. Food Chemistry, 210:35-95.
Plants for Human Health Institute, Food Bioprocessing and Nutrition Sciences Department, North Carolina State University, North Carolina Research Campus, 600 Laureate Way, Kannapolis, NC 28081, United States
Phytochemical and bioactivity analyses of pistachio hulls revealed the presence of anacardic acids (3198 mg/100 g), fatty acids (1500 mg/100 g), and phytosterols (192 mg/100 g) as major components. Carotenoids (4.93 mg/100 g), chlorophylls (10.27 mg/100 g), tocopherols (8.83 mg/100 g), and three triterpene acids (mangiferolic, isomangiferolic and mangiferonic acids) were characterized. A polar (P) extract contained quercetin-3-O-glucoside (6.27 mg/g), together with smaller concentrations of quercetin, myricetin and luteolin flavonoids, accounting for 5.53 mg/g. Gallotannins and other phenolic compounds esterified with a gallic acid moiety characterized the P extract. P extract potently inhibited the release of nitric oxide (NO) and reactive oxygen species (ROS) in lipopolysaccharide-stimulated RAW 264.7 macrophage cells. The mRNA expression levels of the anti-inflammatory cytokine COX-2 were significantly inhibited by fractions P2-P5, while IL-6 was only inhibited by fraction P3. Moreover, the P extract significantly decreased the non-mitochondrial oxidative burst associated with inflammatory response in macrophages.