Application of Green Technology for the Acquisition of Extracts of Araçá (Psidium grandifolium Mart. ex DC.) Using Supercritical CO₂ and Pressurized Ethanol: Characterization and Analysis of Activity

Abstract

Brazil is home to a wide variety of flora, including several lesser known species, such as araçá that were processed in this study using two green technologies consecutively: supercritical fluid extraction (SFE) for nonpolar fraction and pressurized liquid extraction. For polar fraction, the experiments followed a central composite design involving ethanol as solvent, with temperature and static time in each bath as independent variables. Both extracts were analyzed for antioxidant and antimicrobial activities. Total phenolics content (TPC) was determined for all ethanol extracts. In the araçá essential oil (AEO) obtained by SFE, the extraction yield was 2.33%. The three major compounds of AEO were α‐pinene (20.75%), p‐cymene (20.50%), and o‐cymene (20.05%). In ethanol extracts, the high yield (14.49%) was obtained at 74 °C/6 min and the major TPC (136.95 mg GAE/100 g) at 60 °C/9 min. Ethanol extracts presented good antioxidant activity (EC50 = 6.37 mg/mL) at 74 °C/6 min. AEO was unable to reduce DPPH• concentration by 50%. Both extract types presented an inhibitory effect against Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus cereus, while only the ethanol extracts presented effect against Listeria monocytogenes. This work had the aim to present the innovation of the use of a whole typical Brazilian fruit that gives rise to extracts with excellent properties for employment in both the pharmaceutical and food industries.

Promising Green Technology in Obtaining Functional Plant Preparations: Combined Enzyme-Assisted Supercritical Fluid Extraction of Flavonoids Isolation from Medicago Sativa Leaves

“…The first is the commonly known method using the DPPH reagent, in which the extract reacts with DPPH radical solution in ethanol, which leads to reducing the DPPH. The decrease in DPPH concentration is measured at a characteristic wavelength of 517 nm [ 55 , 56 ]. The second method allows the determination of the antioxidant activity through the ability to reduce silver ions and forming silver nanoparticles (AgNPs).…”

Determination of free fatty acids in crude vegetable oil samples obtained by high-pressure processes

“…PLE with intermittent extract purge is an efficient extraction method that was developed in the 1980 s for analytical purposes to extract compounds at low concentrations from samples ( Richter et al, 1996 ). The technique started to be used to obtain extracts with active principles, including “araçá” ( Bittencourt et al, 2019 ) and “candeia” ( Santos et al, 2019 ) extract, and to optimize the conditions for the extraction of matrices, such as coffee grains (N. A. de Oliveira et al, 2018 ).…”

“…High temperatures (T) decrease solvent viscosity, facilitating its penetration and diffusion without solute degradation, while high pressure (P) maintains the solvent in the liquid state under T conditions, in which it would otherwise be in the gaseous state at atmospheric pressure ( Wang & Weller, 2006 ). The optimization of the PLE of vegetable oils using pressurized alcohols, such as ethanol and isopropanol, has been the subject of research by the current research group ( Bittencourt et al, 2019 , Okiyama et al, 2018 ; N. A. de Oliveira et al, 2018 ).…”

Natural antioxidants and lipid profile improvement in lamb meat products

“…The static time (contact time between supercritical CO2 and plant matrix before dynamic extraction) was set at 20 min and the dynamic extraction time set at 5 hours with a CO2 flow rate of 10 g/min. Ethanol was used as a co-solvent (flow rate of 15 g/min) in order to improve the extraction as described by Bittencourt et al (2019).…”