Maceration Time Research Articles

Antibacterial and antihemolytic assessment of Allium Sativum through optimized protein fraction extraction

Background: Garlic (Allium sativum), a widely utilized plant in the Mediterranean region, has long been renowned for its therapeutic properties, primarily attributed to its bioactive compounds such as phenolic compounds and flavonoids. However, the potential of garlic proteins remains largely unexplored. Aims: This study aimed to investigate the in vitro biological activities of the protein fraction extracted from this plant, optimize the extraction process for the garlic protein fraction (GPF), and elucidate its antibacterial and antihemolytic effects. Material and Methods: A Box-Behnken design was employed, using Design Expert 10 Software, to optimize the extraction process of GPF, involving water maceration followed by precipitation using ammonium sulphate. The antibacterial activity of GPF was evaluated against Staphylococcus aureus (FRI 137) and Enterococcus faecalis (ATCC49452) using the well diffusion method. The antihemolytic activity of GPF was evaluated using human erythrocytes. Additionally, the antihaemolytic activity was evaluated using human erythrocytes. Results: The highest extraction yield of 46.57 mg/mL was obtained under the following conditions: pH of 6.22, maceration time of 102 minutes, and temperature of 24.53°C. Remarkably, GPF exhibited significant antibacterial activity, evidenced by inhibition zones of 20 ± 0.5 mm against Enterococcus faecalis and Staphylococcus aureus, two targeted bacterial strains. The minimum inhibitory concentration (MIC) values were determined as 9.36 ± 0.11 mg/mL and 18.72 ± 0.2 mg/mL, while the minimum bactericidal concentration (MBC) values were found to be 37.45 ± 0.13 mg/mL and 18.72 ± 1.08 mg/mL for the respective strains. Furthermore, the investigation of GPF's anti-hemolytic activity on human erythrocytes demonstrated an inhibition rate of 83.77 ± 1.05% at a GPF concentration of 0.25 mg/mL. Conclusions: These findings underscore the significant biological activities associated with the protein fraction of Allium sativum. The protein fraction derived from Allium sativum exhibits notable antibacterial and antihemolytic properties, shedding light on its potential therapeutic applications. Keywords: Allium sativum, Garlic protein, antibacterial properties, hemolysis, RSM.

Analysis of Total Anthocyanin Levels in Hibiscus (Hibiscus rosa-sinensis L.) Preparations by Differential pH Method Using UV-Vis Spectrophotometry

Red hibiscus is a plant that contains anthocyanins and flavonoids which act as natural dyes and preservatives. Anthocyanins are attractive coloring substances and are not harmful to health, therefore they are widely used in the food and pharmaceutical industries. The maximum allowable daily intake of anthocyanins is 0.25 mg/kg body weight. Excessive intake of anthocyanins can cause poisoning. This study aims to determine the total anthocyanin content in hibiscus extract. The method used to analyze anthocyanin levels is the differential pH method using UV-Vis spectrophotometry. The main advantage of this method is that it provides a simple way to measure very small amounts of substances. The results of the research explained that the qualitative analysis showed that the sample was positive for containing anthocyanins because the acid reagent HCl remained red, this was due to the formation of flavilium. The sample with the base reagent (NaOH) changes color to green due to the formation of a carbinol pseudobase structure. Quantitative analysis of anthocyanins showed that in 10.8876 grams of extract there was an anthocyanin content of 72.4731 mg/L at a dilution of 10 ml. The high level of total anthocyanin in the thick hibiscus extract preparation can be influenced by several things such as the temperature during the drying process, the length of maceration time, the concentration of the solvent used, and the high intensity of light

Effects of different low-temperature maceration times on the chemical and sensory characteristics of Syrah wine

This study aimed to investigate the effects of three different cold maceration times on the color, volatiles, and sensory of Syrah wine. The results showed that the physicochemical parameters were not influenced by maceration time. Extending the maceration time significantly increased the color intensity and decreased the hue of the wines. The content of monomeric anthocyanins and monomeric phenols increased gradually with the prolongation of immersion time, however, there was no significant difference between 72 and 120 h. Malvidin-3-O-glucoside was the most abundant monomer in anthocyanins, accounting for 67 % of the total content. Moreover, the highest flavanol content (95.42 ± 0.66 mg/L) was found in 120-h sample. The aroma contents of wines macerated for 72 and 120 h were significantly higher than that of 24 h (p < 0.05). Sensory evaluations showed that extended maceration enhanced the color intensity and floral-fruity aromas of the Syrah wines, while increasing astringency.

Non-Thermal Technology Approaches to Improve Extraction, Fermentation, Microbial Stability, and Aging in the Winemaking Process

Research into non-thermal wine processing technologies is constantly evolving due to the increasing trend towards high-quality, minimally processed, and preservative-free wines. Technologies such as high-power ultrasound, high hydrostatic pressure, pulsed electric field, ultra-high pressure homogenization, and, more recently, cold plasma are some of the best examples currently being explored. This article provides an overview of the latest scientific research into these five non-thermal technologies and their current status in relation to winemaking. By exploring the potential applications of these technologies, it becomes possible to enhance extraction, shorten maceration time, inactivate microorganisms and oxidative enzymes, reduce the addition of chemical additives, accelerate aging, improve wine quality, and much more. However, further experiments are necessary to better comprehend the short- and long-term impacts on the overall quality of the wines produced, especially in terms of sensory characteristics and consumer acceptance. Optimizing processing conditions and scaling up are also of paramount importance to ensure better performance of these technologies at the various stages of winemaking. Additionally, a combined technologies approach has been highlighted as one of the future directions to overcome the limitations of processing with a single technology.

Maceration duration and grape variety: key factors in phenolic compound enrichment of Montenegrin red wine

The present study focuses on the effect of increasing maceration times (0, 2, 4, 6, and 10 days) on the extraction of phenolic compounds into two Montenegrin wines made with the autochthonous varieties Vranac and Kratošija. Significant differences were found in the total acidity, pH and alcohol content of these two varietal wines, which showed different responses to the maceration time. The total content of phenolic compounds (phenols, tannins and anthocyanins) increased significantly with longer maceration time, which is consistent with the existing literature. Specifically, the longest maceration time (10 days) consistently resulted in the highest levels of all parameters analysed. In addition, the anthocyanin profile determined by HPLC showed the interaction between maceration time and variety on the concentrations of the individual anthocyanins. Compared to Kratošija, Vranac wines consistently showed higher anthocyanin contents. In addition, the structural analysis of the tannins revealed that the mean degree of polymerisation (mDP), the percentage of prodelphinidins (%PD) and the percentage of galloylation (%Gall) changed with increasing maceration time. Significant correlations were found between the antioxidant activity values and the analytical parameters, including the structural characteristics of the tannins. This study provides important information on the interaction between maceration time and various varietal characteristics that influence the phenolic composition of Montenegrin wines and contributes to a deeper understanding of winemaking practices and wine quality.

Exploring the Impact of Extended Maceration on the Volatile Compounds and Sensory Profile of Monastrell Red Wine

Volatile organic compounds (VOCs) are crucial to the wine’s overall quality since they define the aromatic profile. The aim of this study was to investigate whether a 146-day extended maceration (EM) treatment positively affects the aromatic and sensory properties of Monastrell red wine. A total of 43 aromatic compounds belonging to different chemical classes were identified using solid-phase microextraction combined with gas chromatography–mass spectrometry (SPME/GC-MS). In general, EM treatment decreased both the number and total relative concentration of VOCs. Specifically, EM decreased the concentration of alcohols, terpenes and sulphur compounds compared to control wines. However certain compounds such as 2-ethyl-1-hexanol, phenylethyl and ethyl decanoate significantly increased with prolonged maceration. Conversely, EM treatment did not significantly affect the total relative concentrations of esters and ketones. From sensorial point of view, the triangular test showed a positive identification of wines (10/18) with a significant preference for EM wines. Moreover, descriptive analysis revealed that EM wines scored lower values in appearance, aroma and taste. Future research should aim to optimize maceration time to enhance the content of VOCs without compromising the sensory quality of the wine.

Ekstraksi Dan Karakterisasi Glukomanan dari Umbi Porang (Amorphophallus Muelleri Blume) dari Perum Perhutani

Porang tubers (Amorphophallus muellei Blume) belong to the Amorphallus genus. Porang tubers contain relatively high levels of glucomannan. Glucomannan is widely used in many industrial fields such as the food, beverage, cosmetics and medicine industries. This research was conducted to determine the sodium metabisulfite ratio levels and maceration time in the process of making porang tuber flour so that optimal porang flour is produced. Varying concentrations of sodium metabisulfite used were 0.2%, 2% and 5% with a soaking time of 1-3 hours and extraction with 60% ethanol. The highest level of glucomannan produced was when using 5% sodium metabisulfite with a 3 hour soaking process with a value of 64.575%.

Phenolic Compound Characterization and Biological Activities of Mistletoe (Viscum album L.) Ethanol Macerates Used in Herbal Spirit Production

Biska, a traditional Istrian herbal spirit, is produced by macerating mistletoe leaves and twigs in a water–ethanol base, usually grape marc spirit. The aim of this study was to determine the optimal mistletoe maceration parameters (ethanol content, concentration of plant material, and duration) for the production of biska, which have not yet been the subject of scientific research. The prepared mistletoe macerates and the collected biska samples were subjected to phenolic compound characterization, including total phenolic content (TPC), total flavonoid content (TFC), and polyphenolic profile, by ultra-high-performance liquid chromatography coupled with mass spectrometry (UPLC-ESI-MS2). In addition, the macerates and the biska samples were analyzed for their biological properties: antioxidant and antiproliferative activity. The results showed that both the macerates and the biska samples contain phenolic compounds of mistletoe such as phenolic acids, flavonoids, and coumarins, which contribute to the observed biological activities—significant antioxidant activity and antiproliferative effect. By applying the maceration parameters, which yielded the highest content of phenolic compounds as well as volatile aromatic compounds (40–80 g/L of mistletoe, 40–55% v/v ethanol, and 21 days’ maceration time), the production process can be improved to produce biska with better aromatic and biological properties.

Effect of High-Power Ultrasound Treatment on Bioactive Compound Content and Chromatic Characteristics of Red Wines

The objective of this work was to investigate, at a laboratory scale, the effect of ultrasound treatment (frequency 20 kHz) on the extraction of total phenolic compounds and monomeric anthocyanins from crushed Merlot grapes in order to reduce maceration time. Antioxidant capacity expressed as ferric reducing antioxidant power (FRAP) and chromatic properties were also investigated. Microvinification was performed on samples both sonicated with a probe-type ultrasonic instrument and untreated (control) and the maceration operation was carried out with sequential extraction (after 3, 5 and 7 days) to evaluate the effect of two factors such as amplitude (A), 70 and 90% and treatment time (t), 3, 4 and 5 minutes on the extraction kinetics of bioactive compounds and chromatic characteristics of the samples. The results showed that throughout the maceration process, the sonicated samples exhibited higher levels of bioactive compounds and chromatic characteristics compared to the control, with the values obtained correlating with maceration time, US treatment time and amplitude. Improvement in all investigated characteristics is evident for ultrasound treated samples compared to untreated ones. Our study provided useful data concerning the impact of ultrasound on the bioactive properties and sensory attributes of red wine, thus offering a theoretical basis for the implementation of this technique in winemaking.

The effect of maceration duration on the total flavonoids content of kaempferia parviflora wall. ex baker ethanol extract

Background: Kaempferia parviflora (Black ginger) has phytochemical compounds such as flavonoids, terpenoids, essential oils, and phenols that have the potential to treat various diseases. To maximize the total extracted flavonoids needs to optimize the extraction duration.Objective: Knowing the optimum maceration duration on the total flavonoid content using the UV-VIS Spectrophotometric method on black ginger ethanol extract.Method: Black ginger is extracted using the maceration method with ethanol (70%) solvent in maceration duration of 12, 24, 36,48, and 60 hours. The extract will be tested qualitatively and quantitative to determine the total levels of flavonoids using the UV-Vis Spectrophotometric method.Result: Qualitative test of black ginger ethanol extract gave positive results for flavonoids, phenolics, alkaloids, steroids, and tannins. The total level of flavonoids in black ginger ethanol extract was 7,8988  0,1223 mgEQ/g (12 hours); 8,5705  0,1529 mgEQ/g (24 hours); 9,8102  0,0416 mgEQ/g (36 hours); 10,6161  0,0768 mgEQ/g (48 hours); 7,2594  0,1244 mgEQ/g (60 hours). The statistical analysis indicates a significant difference (p &lt; 0,05) in the total flavonoid content at each maceration time. Conclusion: The duration of maceration time significantly affects the total flavonoid content produced with the optimum maceration time results at 48 hours

The Generation of Suspended Cell Wall Material May Limit the Effect of Ultrasound Technology in Some Varietal Wines.

The disruptive effect exerted by high-power ultrasound on grape cell walls enhances phenolic extraction, improving chromatic characteristics during red wine maceration. However, short maceration times may, sometimes, hinder this enhancement, and this effect could be attributed to the suspended cell wall material formation facilitated by sonication. This suspended material, having a strong affinity for phenolic compounds, can lead to their precipitation and elimination during subsequent vinification stages and, consequently, a significant portion of extracted phenolic compounds may not contribute to the final phenolic composition of the wine, impacting its chromatic features. To demonstrate this effect, sonicated grapes of two different varieties were vinified with No modified process that eliminated part of this suspended material. Results confirm our hypothesis; that is, the lack of positive outcomes in some cases is due to phenolic compound adsorption on suspended material.

POTENTIAL OF DAYAK ONION SKIN (ELEUTHERINE PALMIFOLIA) EXTRACT AS AN ALTERNATIVE INDICATOR FOR ACID BASE TITRATION PRACTICUM

Synthetic indicators such as phenolphthalein are used during acid-base titrations to determine the end point of the titration. These indicators are not environmentally friendly and the price is high. To overcome this, it is necessary to study the potential of natural indicators available in the environment, one of which was Dayak onion skin which has not been utilized after the tubers have been taken as an anti-cancer herbal medicine. The aim of this research was to determine the potential of Dayak onion skin (Eleutherine Palmifolia) as a natural indicator in acid-base titrations. The sampling collection of Dayak onions was done randomly in the city of Palangka Raya, Central Kalimantan. The method used in this study employed experimental techniques in the chemistry laboratory of FKIP ULM with the following steps: 1) Maceration of smoothed Dayak onion skin with 96% ethanol for 1, 2 and 3 days 2) Qualitative test of anthocyanin, color test with buffer pH 1-14, 3) Absorption measurement with a UV-Vis spectrophotometer at a wavelength of 200 - 400 nm, 4) Application of the extract as an indicator in acid-base titrations. The results showed that the optimum maceration time was on day 3 with an absorption of 4,520 at a wavelength of 380 nm. The application on the HCl – NaOH titration with a titration end point volume of 9.11 mL showed a color change from yellow to straw yellow, while the comparison indicator PP had a volume change of 8.57 mL with a color change from colorless to pink. The CH3COOH – NaOH titration gave a result of 11.43 mL and the PP indicator was 11.01 mL. For the NaHCO3 – HCl titration, the end point volume of the titration was 9.93 mL with a straw yellow – yellow color change and the MO indicator comparison was 10.27 mL with an orange – red color change. From the results of this research, there was a significant color change at the end point of the titration, so it can be stated that Dayak onion skin extract had the potential to be an alternative indicator in acid-base titration practice so that it can be a solution in reducing chemical pollution in the environment.

Effect of Ethanol Concentrations, Honey Adding and Maceration Times on Quality of Mao (Antidesma thwaitesianum) Liqueur

The Mao tree (Antidesma thwaitesianum) is a native and medicinal fruit tree found in Southeast Asia, thriving especially in dipterocarp forests, notably in Northeast Thailand’s Phu Phan valley. Ripe Mao fruits are rich in various nutrients and antioxidants that have the potential to mitigate the risk of chronic diseases and cancer. A comprehensive study was conducted to assess the impact of ethanol at different concentrations (40 or 60 % v/v), with and without honey added. The effects of varying maceration times (0, 3, 6, 9, or 12 months) on Mao liqueur’s properties were also investigated. The investigation explored various parameters, including color, total soluble solids, total acid content, alcohol concentration, and bioactive compounds. The results showed that the color lightness (L*) values of all recipes decreased over the storage period. However, adding honey to the production of Mao liqueurs decreased the yellowness (b*) value in the first 3 months but resulted in a higher total soluble solid content in Mao liqueur. Increasing the ethanol concentration from 40 to 60 % did not affect the total acid content (TTA 0.04 %). However, the addition of honey increased the total acid content from 0.04 to 0.08 % (p ≤ 0.05). The maceration time did not affect the alcohol content of Mao liqueur (p &gt; 0.05). The use of 60 % (v/v) ethanol with honey addition resulted in the highest alcohol content (42 % v/v). Increasing the ethanol solution concentration from 40 to 60 % with and without honey added increased the total phenolic content from 126 to 165 GAE mg/L and 136 to 160 GAE mg/L respectively. The addition of honey increased the anthocyanin content in the liqueurs in the 12th month. HIGHLIGHTS Alcohol contents, maceration times and effect of honey adding were studied to improve the quality of liqueur made of Mao (Antidesma thwaitesianum) Mao liqueurs of 60 % EtOH had large changes in their alcohol contents during the maceration time 3 - 6 months Increasing the ethanol solution concentration from 40 to 60 % increased the total phenolic content The addition of honey increased the anthocyanin content in the liqueurs in the 12th month GRAPHICAL ABSTRACT

Determination of malvidin-3,5-diglucoside content in wines from Cabernet Cortis and three Italian-resistant hybrids, with preliminary evaluation of oenological glycosidases for enzyme-induced breakdown of malvidin-3,5-diglucoside and malvidin-3-glucoside

ABSTRACT The content of malvin (malvidin-3,5-diglucoside) was determined in a set of wines obtained from Cabernet Cortis and other three recently introduced grape-resistant hybrids (Cabernet Volos, Merlot Khantus and Merlot Khorus) produced in South Tyrol (Italy), to establish their conformity to legal requirements and suggest winemaking approaches for their production and use. Different skin maceration times and ageing periods were considered for the wines investigated. Malvin content exceeded the limit of 15 mg/L, imposed by the Italian government for the commercialization of wines, in 18 out of 21 samples and showed a significant decrease during wine ageing (by about 40–50% every 12-month period) with the scarce effect of maceration time and fermentation temperature. Single-cultivar wines became suitable for commercialization after ca. 7 years ageing, following traditional winemaking approaches. The use of two commercial enzymatic pectolytic preparations indicated for aroma enhancement and possessing β-glucosidase activity was also investigated at two different dosages, to increase the degradation rate of malvin in wines after winemaking. They are unsuitable for significant malvin content decrease within a 6-month time lapse.

Application of two-level factorial design in optimization of maceration extraction of Curcuma longa curcuminoids extracts

A two-level factorial design was used to identify extraction factors that could improve Curcuma longa rhizome extraction yield (EY) and curcuminoid content (CC). These extraction factors included solid/liquid ratio (A: 0.10– 0.20 g/mL), ethanol concentration (B: 50–70%), and time maceration (C: 3–6 h). Under the prevailing circumstances, the yield of extract and CC varied from 2.86% to 20.90% and from 1.80% to 21.59%, respectively. The findings indicated that all three parameters were statistically significant (P &lt; 0.05) in contributing to increase EY. The increase in CC was significantly influenced by ethanol concentration alone. Therefore, these findings suggest that adjusting the solid/liquid ratio, ethanol concentration, and maceration time can enhance the efficiency of curcuminoid extraction from C. longa rhizomes.

Improving Hydroxytyrosol Derivatives Content in Virgin Olive Oil using Ultrasound-assisted Maceration with Olive Leaf Extract

Background: Olive oil is rich in monounsaturated fatty acids and is an essential Mediterranean diet component. Many of its health benefits are associated with the presence of phenolic compounds. Several strategies for the enhancement of the phenolic content and, more specifically, the concentration of hydroxytyrosol derivatives in olive oils have been proposed, as extra virgin olive oil (EVOO) of high phenolic content is preferred by health-conscious consumers. Methods: The supplementation of EVOO with hydroxytyrosol derivatives from olive leaf extract was performed with the employment of ultrasound-assisted maceration at different concentration levels (2 g·L-1 oil and 4 g·L-1 oil), temperatures (20 and 40°C), and maceration times (20 and 40 min). The phenolic contents of enriched EVOOs were determined by spectrophotometric and HPLC methods. In addition, the effect of supplementation on the physicochemical parameters of EVOOs, namely acidity and extinction coefficients (K232 and K270), was also studied. Results: The addition of extract slightly increased the acidity values and extinction coefficients of the samples, and at the same time, it significantly improved their phenolic composition. The use of appropriate ultrasound-assisted maceration parameters (addition of olive leaf extract at a concentration level of 2 g L-1 at 20°C for 20 min) provided EVOO with acceptable values for total acidity (&lt;0.8%), K232 (&lt;2.5), and K270 (&lt;0.22), high contents of total phenolics and flavonoids, and improved hydroxytyrosol derivative contents. Conclusion: The enrichment of EVOO with leaf extract is a promising strategy to enhance its content in hydroxytyrosol derivatives, providing premium EVOOs with respect to their bioactive composition.

Efekti spontane i inokulisane fermentacije na sadržaj ukupnih fenolnih jedinjenja i antioksidativnu aktivnost vina Cabernet Sauvignon i prevrele komine

The total phenolic content and antioxidant activity of wine and fermented pomace (FP) from Cabernet Sauvignon grapes harvested at the stage of full ripeness were evaluated by spectrophotometric analysis. Wine and pomace were obtained after prolonged maceration during spontaneous and inoculated fermentation of fully ripe grapes. Three individual vinifications were inoculated with the following commercial yeasts: BDX (Lallemand, Montréal, QC, Canada), FX10 (Laffort, Bordeaux, France) and Qa23 (Lallemand, Montréal, QC, Canada). For each vinification, maceration lasted 0, 3, 5, 7, 14 and 21 days, respectively. The total phenolic content was determined spectrophotometrically using the Folin-Ciocalteu method. Two different methods were used to evaluate the antioxidant activity of the wine and pomace samples: the Ferric Reducing Activity of Plasma (FRAP) and the Trolox Equivalent Antioxidant Capacity (TEAC). The use of a winemaking process that included different maceration times and inoculation with yeasts, as well as spontaneous fermentation, significantly modulated the total phenolic content of the obtained wines and FP. This study could provide a good basis for the practical application and obtaining wines with a high content of phenolic compounds and antioxidant properties.

Influence of prolonged maceration on phenolic compounds, volatile profile and sensory properties of wines from Minutolo and Verdeca, two Apulian white grape varieties

Prolonged maceration was applied to two Apulian white grape cultivars, Minutolo and Verdeca. The impact of prolonged maceration (up to six months) on the quality of the wines was evaluated through characterization of phenolic, volatile and sensory profiles. Macerated wines presented a peak of extraction after 4 months, followed by a decrease probably due to precipitation/reabsorption. Extraction of seed phenols occurred during longer maceration times. Volatile profile was also modified, showing a different behavior at different maceration times. Oxidation and aging compounds appeared during maceration, that are unusual for traditional white wines. Furthermore, maceration successfully enhanced varietal identity of Minutolo. The terpene profile of Minutolo wines changed during maceration, with a maximum of terpenols after 1 month of maceration, while longer maceration added a pattern of oxidized terpenes. Sensory analysis highlighted clearly distinct profiles of wines, according to both cultivar and maceration time. A good attitude was observed of both varieties to undergo maceration. In particular, Verdeca appeared suitable for longer maceration times, with flowery, citrus and apricot notes after 4 months, while enhanced apricot notes were perceived after 6 months. On the other hand, Minutolo wine after 6 months of maceration was characterized by a marked astringency and peach flavor.

Optimization of the Extraction of Bioactive Compounds from Cabernet Sauvignon Grape Pomace from Querétaro, Mexico, Using MSPD

Red wine contains polyphenols which are extracted during the winemaking process. However, winemaking is not an extraction; therefore, the resulting byproducts still have a substantial polyphenol content. The aim of this study was to compare two methods for the extraction of phenolic compounds: maceration and matrix solid-phase dispersion (MSPD). Grape pomace (Vitis vinifera var. Cabernet Sauvignon) from a winery in Querétaro, Mexico was used. The optimal conditions for both methods were identified. Phenolic compounds and antioxidant activity were the response variables. A central composite design was used (Minitab 17) for the extraction by maceration. The maceration time (1, 4, 12, 20, and 24 h) and the ratio of ethanol (50 to 80%) acidified with 1% HCl were the two factors studied. For the MSPD extraction, sea sand was used as a dispersant, and a 22 factorial design was employed for the evaluation, with the elution volume and the ratio of sample/dispersant being the two factors analyzed. The optimal extraction method was MSPD with 96 mL (acidified ethanol) as the elution volume and a 1:2 ratio of sample/dispersant. Using these conditions, 14.01 ± 0.19 mMol TEAC/100 g db (Trolox equivalent of antioxidant capacity) of grape pomace was obtained, whereas the total phenolic content was 2836.73 ± 41.90 mg GAE/100 g db. These values are greater than those obtained by maceration. These conditions are close to those predicted by the model (analysis of variance (ANOVA) with a level of significance of 5% (p &lt; 0.05) and a Tukey comparison test for determining significant differences in the comparison of results).

Extraction of flavonoids from durian (Durio zibethinus) fruit rinds and evaluation of their antioxidant, antidiabetic and anticancer properties

SummaryDurian (Durio zibethinus) fruit rinds are a promising source of bioactive phytochemicals, but they are currently wasted. This study optimised extraction conditions for flavonoids from durian fruit rinds and evaluated the biological activities of the flavonoid‐rich extracts. The highest flavonoid content of 82.17 mg QE g−1 extract was achieved when performing the extraction at 60 °C using 75% ethanol and maceration time of 24 h. The crude ethanolic extract was then fractionated using liquid–liquid extraction to obtain three fractions (CHF, EAF and AQF). Among them, CHF demonstrated the highest amount of flavonoids (271.11 mg QE g−1 extract) and quercetin (1006.19 μg g−1 extract). This fraction also exhibited the highest ferric reducing power (IC50 of 307.88 μg vitamin C g−1), DPPH radical scavenging activity (IC50 of 38.72 μg mL−1), α‐amylase and α‐glucosidase inhibitory activity (IC50 of 685.76 μg mL−1 and 441.10 μg mL−1, respectively) and cytotoxicity against HepG‐2 and MCF‐7 cells with IC50 values of 490.30 μg mL−1 and 343.38 μg mL−1 respectively. The current work suggested that durian fruit rinds are a potential source of flavonoids and the CHF could be further used for pharmaceutical applications.