Conventional extraction techniques for phytochemicals

Influence of Acidity and Extraction Time on the Recovery of Flavonoids from Grape Skin Pomace Optimized by Response Surface Methodology

“…On the other hand, several-fold higher values were reported elsewhere (52.7±5.0 mg g -1 ), likely due to the application of different extraction techniques 42 . From all the observed polyphenols, and accordant with the favorable influence of acidity on their extraction 14 , flavonols showed the clearest influence of acidity on their recovery from grape skin pomace extracts ( Table 2). The highest average experimental amounts of flavonols (9.85±1.55 mg g -1 d.m.)…”

“…It has previously been shown that increased acidity supports extraction of phenolic acids and total phenols together with increased antioxidant capacity of extracts 23 . Extraction time varies with regards to different plant material and particle sizes, where smaller particles of plant material tend to reduce extraction time 14 . Due to these numerous sources of variation, it is important to quantify those influences that have an effect on the amount of extracted flavonoids in different grape pomaces.…”

“…Ethanol is generally recognized as safe (GRAS status), and is commonly used as organic solvent in conventional extraction of polyphenols 21 . Increased temperature improves extraction due to better diffusion and disruption of plant cellular structures 14,21 . Increased acidity induced by the use of strong acids, such as HCl, with elevated temperatures, tends to shorten the extraction time of polyphenols (e.g.…”

“…Phytochemicals such as flavonoids are commonly recovered from plants by solid-liquid extraction 14 . Extraction of target compounds from grape pomace is mainly affected by grape variety/ vintage, type of extraction/solvent, acidity, temperature, time, addition of enzymes, and particle size [14][15][16][17][18][19][20] . Ethanol is generally recognized as safe (GRAS status), and is commonly used as organic solvent in conventional extraction of polyphenols 21 .…”

Investigation on antimicrobial activity and phytochemical screening of Randia spinosa (Thunb.) Poir. and Dillenia pentagyna Roxb.

“…Earlier studies indicated that the medicinal plants are used against parasitic and microbial infections including bacterial, viral and fungal infections [20][21][22][23][24][25][26]. The present work reveals antimicrobial properties in D. pentagyna and R. spinosa.…”