Investigation on supercritical CO2 extraction of phenolic-phytochemicals from an epiphytic plant tuber (Myrmecodia pendans)

摘要

Myrmecodia pendans (ant-nest) is an epiphytic plant with rich content of\udphytochemicals. In this work, the application of supercritical carbon dioxide\ud(SC-CO2) for extracting several polyphenol and flavonoid compounds from ant-nest tuber include gallic acid, catechin, ferulic acid, caffeic acid, p-coumaric acid,\udquercetin, luteolin and kaempferol was investigated. Static-analytical extraction\udexperiments were performed at pressures ranged between 9–22.5 MPa and temperatures of 313.15–343.15 K for 6–7h. Solubility data of total polyphenols\ud(gram gallic acid equivalent (GAE)/L CO2) and total flavonoids (gram quercetin\udEquivalent (QE)/L CO2) were modeled using Chrastil and Del Valle–Aguilera\uddensity-based equations. Both equations were able to represent actual solubilities\udsatisfactorily in terms of correlation coefficient and parameter consistency.\udDPPH-scavenging test showed high antioxidant capacity of supercritical extract\udWith an IC50 level of 3.62 ±0.12 mg/mL. It was observed a positive linear\udcorrelation between bioactive contents of antioxidant extract and the potency of\udscavenger activity against DPPH free radical.