@conference{
author = "Čutović, Natalija and Jovanović, Aleksandra and Rajab Elferjane, Rajab Elferjane and Milutinović, Violeta and Petrović, Predrag and Marinković, Aleksandar and Bugarski, Branko",
year = "2023",
abstract = "Aloe vera (L.) Burm. f. (Asphodelaceae) contains anthraquinones, their glycosides, flavonoids,
tannins, terpenoids, saponins, resins, mono- and polysaccharides, polypeptides, lectins, enzymes,
vitamins, and minerals. The plant is used in traditional medicine due to its antitumor,
antioxidant, anti-inflammatory, antiulcerogenic, immunomodulatory, analgesic, and dermal
protection properties. Maceration and heat-assisted extraction (HAE) are frequently used
extraction procedures because of their simple operation and low costs. In the present study, A.
vera dried leaves were extracted using ethanol (50%, V/V; drug solvent ratio 1:30, w/V). The
influence of different extraction times (30-120 min for maceration and 15-60 min for HAE), and
various extraction temperatures (40, 60, and 80ºC) in HAE on the total polyphenol content
(TPC) and radical scavenging potential (ABTS and DPPH methods) was evaluated, while for the
most prominent extracts (with the highest TPC) zeta potential and conductivity were additionally
analyzed. Regarding maceration, the TPC was correlated with the rise in extraction time up to
45 min (from 7.8±0.72 to 9.66±0.51 mg gallic acid equivalents (GAE)/g of plant material) and
after that reached the steady state (~9.1 mg GAE/g). In HAE, no statistically significant
differences between the TPC of the extracts obtained after 15, 30, and 45 min (9.77±0.32,
9.76±0.18, and 9.95±0.50 mg GAE/g) were observed, while the extract prepared after 60 min
showed significantly lower TPC (8.14±0.08 mg GAE/g). The TPC was in correlation with the
increase of extraction temperatures (9.08±0.21 at 40ºC, 9.38±0.10 at 60ºC, and 9.86±0.24 mg
GAE/g at 80ºC). As in the case of TPC results, anti-ABTS activity was significantly different
between 30 and 45 min of maceration and reached the steady state after 45 min (~2.01 mmol
Trolox/g of plant material). In HAE, the anti-ABTS potential of the extracts obtained at different
extraction times was comparable (1.44-1.64 mmol Trolox/g), whereas the activity of the extract
obtained at 40ºC was lower. DPPH radical scavenging activity rose after 45 min of maceration
when also reached the steady state (~40.4 mg/mL), but there were no significant differences
between the extracts prepared at different extraction times in HAE, and IC50 was lower for the
extract obtained at 80ºC. Hence, the macerate prepared after 45 min and HAE extract obtained
after 15 min at 80ºC exhibited very low zeta potential (0.14±0.06 and 0.50±0.01 mV), and
conductivity (1.05±0.07 and 0.98±0.01 mS/cm). This study was an initial step in the production of A. vera polyphenol extracts aimed to be used for the formulation of foodstuffs, medicines, and
cosmetics.",
publisher = "University of East Sarajevo, Faculty of technology",
journal = "VIII International Congress “Engineering, Environment and Materials in Process Industry-EEM2023", Jahorina, March 20-23, 2023, Republic of Srpska, Bosnia and Herzegovina, Proceedings",
title = "Maceration and heat-assisted extraction of polyphenols from Aloe vera",
pages = "136-143",
url = "https://hdl.handle.net/21.15107/rcub_farfar_5261"
}