ABSTRACT
This study aimed to investigate the efficacy of supercritical CO2 (SC-CO2) extraction in enhancing the extraction rate, purity, and antioxidant activity of Indocalamus latifolius (Keng) McClure (Poaceae) leaf terpenoids (ILLTs). Crude extracts obtained from leaves were subjected to qualitative and quantitative analyses, revealing neophytadiene, phytol, ß-sitosterol, ß-amyrone, squalene, and friedelin as the primary terpenoid constituents, identified through gas chromatography-mass spectrometry (GC-MS). Compared with steam distillation extraction (SD), simultaneous distillation extraction (SDE), ultra-high pressure-assisted n-hexane extraction (UHPE-Hex), ultra-high pressure-assisted ethanol extraction (UHPE-EtOH), ultrasound-assisted n-hexane extraction (UE-Hex), and ultrasound-assisted ethanol extraction (UE-EtOH), SC-CO2 exhibited a superior ILLT extraction rate, purity, and antioxidant activity. Scanning electron microscopy (SEM) observations of the residues further revealed more severe damage to both the residues and their cell walls after SC-CO2 extraction. Under optimal parameters (4.5 h, 26 MPa, 39 °C, and 20% ethyl alcohol), the ILLT extraction rate with SC-CO2 reached 1.44 ± 0.12 mg/g, which was significantly higher than the rates obtained by the other six methods. The subsequent separation and purification using WelFlash C18-l, BUCHI-C18, and Sephadex LH-20 led to an increase in the purity of the six terpenoid components from 12.91% to 93.34%. Furthermore, the ILLTs demonstrated cytotoxicity against HepG2 cells with an IC50 value of 148.93 ± 9.93 µg/mL. Additionally, with increasing concentrations, the ILLTs exhibited an enhanced cellular antioxidant status, as evidenced by reductions in both reactive oxygen species (ROS) and malondialdehyde (MDA) levels.
ABSTRACT
BACKGROUND: This study provides an insight into the impact of ultrasound-assisted extraction with water as solvent (UAEW) and extraction by supercritical carbon dioxide (SC-CO2 ) with 5% EtOH on antioxidant and enzyme inhibitory activity in regard to the chemical profile of the edible and medicinal mushroom, Pleurotus pulmonarius. RESULTS: Extraction efficiency was between 0.36% and 63.32%, depending on the extraction technique. The main compounds in the extracts were fatty acids. Supercritical CO2 extraction with co-solvent was the most suitable method for obtaining extracts that were rich in ergosterol content, reaching a value of 40.1 mg g-1 . The UAEW of crude mushroom powder ensured the highest yield, as well as the extracts with best antioxidative activity. The measurements of enzyme inhibitory activity revealed that all types of investigated extracts exhibited only tyrosinase and amylase inhibition at a significant level. CONCLUSION: Based on our results, the extraction methods significantly affected the chemical profile and bioactivity of P. pulmonarius. © 2020 Society of Chemical Industry.