Cancer preventive and neuroprotective potentials of red hulls, kernels and oleo-gum resins from Pistachio

Abstract

This research was performed to assess cancer prevention and neuroprotective capacities of different parts of Pistachio (Pistachio vera L.). Red hulls, kernels and oleo-gum resins of Pistachio were extracted with methanol-MeOH and distilled water-dH2O, and subjected to in vitro biological assays varying from 100 to 1000 μg mL−1 concentrations. Their anticancer activities were evaluated against A549, MCF-7, and HeLa human cancer cells. Neuroprotective activities of the extracts were tested through enzyme inhibition on AChE, BChE, and TYR, which are closely related to pathogenesis of neurobiological disorders, particularly Alzheimer's and Parkinson’s diseases. Due to cancer and neurodegenerative diseases are associated with oxidative damage, the extracts were analyzed for their antioxidant activities. With respect to free radical scavenging activities of the extracts, red hull extracts were found as the most potent ones both DPPH (67.95±1.13 to 80.55±0.12%) and ABTS (86.92±0.10 to 92.04±1.06%) radicals. The highest anticancer activity were determined in MeOH and dH2O extracts obtained from oleo-gum resin against HeLa cells (IC50 = 18.50±0.85 and 28.97±0.08 µg mL-1, p< 0.01, respectively), whilst dH2O-kernel extract was found to have the weakest anticancer activity towards A549 cells (IC50 = 268.66±1.02 µg mL-1, p< 0.01). Neuroprotective potentials on AChE and BChE enzymes were resulted in the superiority of dH2O-red hull extract was exerted the highest inhibition on AChE and BChE enzymes with 81.50±0.08 and 62.96±1.01% inhibition, respectively. However, dH2O extract from oleo-gum resin showed the highest inhibitory effect on TYR enzyme (58.16±0.18% inhibition). P. vera is of valuable nutritional source for human diet. Other than kernel parts used as food, waste parts like red hulls and oleo-gum resins have been proven as a potential pharmacological source. Consequently, this study reveals that non-food parts of Pistachio could be valuable source for pharmaceutical industry.