Phytochemical Studies on Mastic Gum of Pistacia lentiscus var. chia Collected from Karaburun Peninsula and Neuroprotective Activities of the Isolates

Pistacia lentiscus L., called mastic tree, grows extensively in coastal areas of the Mediterranean. It has been traditionally exploited as a dietary or cosmetic agent and to treat gastrointestinal disorders. While the chemical constituents of Chios mastic gum comprise natural polymers, essential oils, and triterpenic compounds, further studies have suggested that triterpenes are of great importance in biological activities such as anti-inflammatory, antimicrobial, antioxidant, and chemopreventive [1]. Since the abiotic factors affect the secondary metabolite profile [2], our group has decided to undertake a phytochemical study on Pistacia lentiscus var. chia growing in Karaburun Peninsula, İzmir-Turkey.

Isolation and purification studies were performed using chromatographic methods; subsequently, structural elucidation was done by spectroscopic methods (1D NMR, 2D NMR, MS and X-RAY). The detailed inspections of spectra helped us establish structures of twelve molecules possessing triterpenic skeletons ([Fig. 1]), and two of them turned out to be undescribed compounds. Since oxidative stress leads to the progression of neurodegenerative disorders [3] and antioxidant activities of some Pistacia species are documented [4], the neuroprotective effect of the isolates was examined against H₂O₂-induced oxidative stress on SH-SY5Y cells. As differentiation agents were reported to affect potency of compounds [5], both differentiated and undifferentiated SH-SY5Y cells was used in this study. Two compounds (oleanolic acid and 17-β-hydroxy-28-norolean-12-ene-3-one) showed neuroprotective effects, while others demonstrated little or no effect. Interestingly, 17-β-hydroxy-28-norolean-12-ene-3-one exhibited protective activity in both differentiated and undifferentiated SH-SY5Y cells whereas oleanolic acid had effects only on undifferentiated cells.

Fig. 1 Isolated triterpenoids from Pistacia lentiscus var chia.

• References

• 1 Pachi VK, Mikropoulou E v. Gkiouvetidis P. et al. Traditional uses, phytochemistry and pharmacology of Chios mastic gum (Pistacia lentiscus var. Chia, Anacardiaceae): A review. Journal of Ethnopharmacology 2020; 254
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• 3 Mohd Sairazi NS, Sirajudeen KNS. Natural Products and Their Bioactive Compounds: Neuroprotective Potentials against Neurodegenerative Diseases. Evidence-based Complementary and Alternative Medicine 2020; 2020
• 4 Pacifico S, Piccolella S, Marciano S. et al. LC-MS/MS profiling of a mastic leaf phenol enriched extract and its effects on H2O2 and Aβ (25–35) oxidative injury in SK-B-NE(C)-2 Cells. Journal of Agricultural and Food Chemistry 2014; 62 DOI: 10.1021/jf504544x.
• 5 Zhang T, Gygi SP, Paulo JA. Temporal Proteomic Profiling of SH-SY5Y Differentiation with Retinoic Acid Using FAIMS and Real-Time Searching. Journal of Proteome Research 2021; 20 DOI: 10.1021/acs.jproteome.0c00614.

Publication History

Article published online:
12 December 2022