Utilization of the integrated process of supercritical extraction and impregnation for incorporation of Helichrysum italicum extract into corn starch xerogel

Abstract

Article Highlights • Starch xerogels were impregnated with H. italicum extract by scCO 2 extraction-impregnation process • Influence of different process parameters on impregnation yield was studied • Influence of ethanol on the extract's chemical profile and impregnation yield was determined • Selected process conditions enabled sufficient quantity of impregnated extract Abstract Supercritical CO 2 extraction of Helichrysum italicum and impregnation of starch xerogels with the extract by using an integrated scCO 2 extraction and impregnation process were performed at 350 bar and 40 °C in order to produce biomaterials for possible oral intake of the extract. Xerogels produced by air-drying of acetogels and alcogels were used as carriers in the supercritical impregnation process. The effect of ethanol as a co-solvent, contact time, plant material/carrier mass ratio and xerogel preparation on the impregnation loading was studied. The highest impregnation loading (1.26±0.22%) was achieved after 5 h impregnation of the xerogel obtained from alcogel using pure scCO 2 and plant material/ /carrier mass ratio of 10. Chemical analysis of the extracts showed that the addition of ethanol as co-solvent had a positive effect on scCO 2 selectivity to terpene fraction and total flavonoids, while it lowered the total phenolic content. Despite the difference in chemical composition, both extracts expressed similar antioxidant activity according to the DPPH and FRAP methods. The integrated process was shown to be a feasible method for isolation and incorporation of bioactive components of H. italicum into starch xerogels.

Application of a Natural Antioxidant from Grape Pomace Extract in the Development of Bioactive Jute Fibers for Food Packaging

“…or that being a functionalization technique after the polymerization of the matrix do not compromise the polymerization step [ 33 ]. Besides, it offers the possibility to combine both SFE and SSI in a continuous system [ 34 , 35 ]. Numerous investigations have focused on the supercritical impregnation of natural extracts, such as thyme [ 36 ], clove [ 37 , 38 ] or oregano essential oils [ 39 ] among others, into synthetic polymeric films.…”

Supercritical CO2 impregnation of Gelatin-Chitosan films with clove essential oil and characterization thereof

“…At the same time, scCO 2 is also known for its high diffusion ability in organic matter and near zero surface tension as well as for promoting polymer swelling and changing polymer structural properties by a plasticization effect [38][39][40][41]. The combination of aforementioned properties makes this fluid a good medium for impregnation of solid matrices with active substances soluble in scCO 2 [42,43]. Supercritical solvent impregnation (SSI), and namely impregnation using scCO 2 , has several advantages over traditional methods for polymer impregnation.…”

Supercritical Fluid Applications in the Design of Novel Antimicrobial Materials

“…In the case that different process conditions are required in the extractor and adsorber, a BPR can be placed between the vessels. The integrated process has been successfully applied to add antibacterial properties to a variety of polymeric and textile materials [28][29][30][31][32][33][34]. Cotton gauze and polypropylene nonwoven fabric were impregnated with thyme extract rich in thymol, whereby the extract loadings of 9% and 5% were obtained for cotton and polypropylene, respectively [29].…”

“…The gels were impregnated with thymol in a batch SSI at 15.5 MPa and 35 • C for 24 h. The loadings obtained were in the range of 1.15-4.02% [74]. In the subsequent study [33], curry plant (Helichrysum italicum) extract, known for its antibacterial properties, was incorporated into the starch xerogel in the integrated SFE-SSI process. Both processes, the extraction and impregnation, were performed at 35 MPa and 40 • C. The highest loading of around 1.26% was obtained for the scCO 2 circulation through the extractor and adsorber during 5 h and with the plant material/starch mass ratio of 10 [33].…”

“…In the subsequent study [33], curry plant (Helichrysum italicum) extract, known for its antibacterial properties, was incorporated into the starch xerogel in the integrated SFE-SSI process. Both processes, the extraction and impregnation, were performed at 35 MPa and 40 • C. The highest loading of around 1.26% was obtained for the scCO 2 circulation through the extractor and adsorber during 5 h and with the plant material/starch mass ratio of 10 [33]. Varona et al [55] impregnated starch modified with the n-octenyl succinate (OSA) in powder form with lavandin essential oil.…”