Search

Background: Blackberry seeds, as a by-product of processing, have potential bioactive substances and activities. A response surface method was used to determine the optimal conditions of blackberry seed extracts (BSEs) with high 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity by ultrasound-assisted extraction (UAE). The composition and antioxidant capacity of BSEs were further analyzed., Results: The optimal conditions were material-to-liquid ratio of 0.07 g mL -1 , ethanol concentration of 56%, extraction temperature of 39 °C and ultrasonic power of 260 W. Using these conditions, the extraction yield and total polysaccharide, phenolic and anthocyanin contents in BSEs were 0.062 g g -1 and 633.91, 36.21 and 3.07 mg g -1 , respectively. The Fourier transform infrared spectra of BSEs exhibited characteristic peaks associated with polysaccharide absorption. The antioxidant capacity, DPPH and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity, and ferric reducing antioxidant power of BSEs were 1533.19, 1021.93 and 1093.38 mmol Trolox equivalent g -1 , respectively. The delphinidin-3-O-glucoside, paeoniflorin-3-O-glucoside and cyanidin-3-O-arabinoside contents in BSEs were 3.05,12.76 and 1895.90 ± 3.45 μg g -1 . Five polyphenols including gallic acid, coumaric acid, ferulic acid, catechin and caffeic acid were identified and quantified in BSEs with its contents at 8850.43, 5053.26, 4984.65, 1846.91 and 192.40 μg g -1 ., Conclusion: These results provide a method for preparing BSE containing functional components such as polysaccharides, phenols and anthocyanins through UAE, and BSEs have potential application in food industries. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

In addition to their pigment properties, the potential health benefits of anthocyanins have made them a subject of interest in recent years. This study aimed to obtain purified anthocyanin fractions from native Mexican black bean cultivars using Amberlite XAD-7 resin column and HPCCC and evaluate their anti-inflammatory properties using RAW 264.7 cells. The major anthocyanins in the purified anthocyanin fractions were delphinidin 3-glucoside (61.8%), petunidin 3-glucoside (25.2%), and malvidin 3-glucoside (12.2%). Purified anthocyanin fractions at 12.5 μg/mL effectively prevented LPS-induced ERK1/ERK2 phosphorylation and reduced the protein expression of COX-2 and mRNA expression of iNOS. Results showed that purified anthocyanin fractions have the potential to modulate the inflammatory response by inhibiting the production of pro-inflammatory mediators through the ERK1/ERK2 and NF-κB pathways. This study suggests that anthocyanins from black beans could be used as a natural strategy to help modulate inflammation-associated diseases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Butterfly pea flower (BPF), roselle calyx (RC), and grape skin (GS) are rich in bioactive phenolics with health benefits. Due to its simplicity, safety, and environmental friendliness, this study used water as a solvent to explore different extraction conditions in these plant materials and compared the heat stability of anthocyanins in the aqueous extracts. To maximize the total anthocyanins and polyphenols in the aqueous extracts, the powders of BPF, GS, and RC should be extracted for 30 min at 90 °C; 30 min and 120 min at 90 °C; and 30 min and 60 min at 60 °C, respectively. Among the tested plant materials, the content of total anthocyanins was RC > GS > BPF, while the total phenolic content was GS > BPF > RC. Anthocyanins of the aqueous extracts underwent rapid thermal degradation at high temperatures and high pH values. The thermal stability of anthocyanins in the materials was in the order: BPF > GS > RC. This is likely related to the types and structures of the anthocyanins such as the degree of acylation and glycosylation. The study demonstrates that hot water extraction is efficient and practical for these materials, yielding extracts suitable for food and nutraceutical applications.

Anthocyanins are natural pigments, known for their antioxidant, anti-inflammatory properties, and health benefits. One method to extract anthocyanins uses natural deep eutectic solvents (NADES). NADES are mixtures of two or more natural compounds that result in a liquid with a lower melting point than any of its individual components. NADES are nontoxic, biodegradable solvents that can be obtained from renewable sources, making them an attractive alternative to traditional solvents; therefore, they are known as the "21st century solvents." This review provides a comprehensive and critical assessment of the use of NADES as a sustainable solvent system for anthocyanins extraction. It also discusses the main properties of anthocyanins, NADES, process parameters, and economic and environmental analysis to efficiently extract anthocyanins. Current state of knowledge focusing on its applicability within the industrial context was evaluated and identified gaps in knowledge, highlighting its advantages and challenges to provide recommendations for future research., (© 2024 Institute of Food Technologists®.)

Background: To extract anthocyanins with high efficiency, a hypothesis for high-speed shear homogenization extraction (HSHE) method was established through a combination of solvent and ultrasonic-assisted extractions. The efficacy of this hypothesis was demonstrated by performing qualitative and quantitative analyses of 16 anthocyanins extracted from five northern vegetables, and five berry fruits using ultra-high-performance Q-Exactive Orbitrap tandem mass spectrometry. Single-factor experiments were conducted by varying ethanol concentration, temperature, pH and extraction cycles to determine the optimal conditions for this method., Results: Optimal extraction conditions (ethanol 70-80%, 40-50 °C, pH 3-4, performed twice) were determined using an HSHE (5 min, 10 000 rpm, 25 °C) assisted shaker (60 min) and ultrasonication (40 kHz, 160 W cm -2 , 30 min, 25 °C) procedure. Compared to the traditional non-HSHE method, the total anthocyanin content obtained through HSHE extraction showed a significant increase, ranging from 1.0 to 3.9 times higher, with purple cabbage exhibiting the most pronounced enhancement in content. More types of anthocyanins were detected in blueberry (9), black bean (7) and raspberry (5), of which malvidin was the major anthocyanin (0.426 g kg -1 ) in blueberry, having an amount five times than previously obtained., Conclusion: The established HSHE method has been proven to be a superior technique for anthocyanin extraction, with higher extraction efficiency and concentrations. This technique also provides a new avenue for extracting bioactive compounds from diverse food sources, with potential applications in improving the functional properties of food products. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

Cyanidin-3-O-galactoside (Cy3-gal) is the most widespread anthocyanin that has been found to be applicable to nutraceutical and pharmaceutical ingredients. Nevertheless, the process of separation and purification, susceptibilities to heat, and pH inactivation present some limitations. In the present study, natural deep eutectic solvents (NADES) with an ultrasonic-assisted extraction method were briefly studied, and the recovery of Cy3-gal from Rhododendron arboreum was highlighted. The NADES, consisting of choline chloride and oxalic acid (1:1), was screened out as an extractant, and single-factor experiments combined with a two-site kinetic model were employed to describe the extraction process. Further, the work investigated ultrasound-assisted adsorption/desorption to efficiently purify Cy3-gal using macroporous resins. The optimal extraction conditions to attain maximum Cy3-gal yield was 30% water in a 50:1 (mL/g) solvent-to-sample ratio, 11.25 W/cm 3 acoustic density, and 50% duty cycle for 16 min of extraction time. Under these conditions, the results revealed 23.07 ± 0.14 mg/g of Cy3-gal, two-fold higher than the traditional solvents. Furthermore, of the different resins used, Amberlite XAD-7HP showed significantly (p < 0.05) higher adsorption/desorption capacities (12.82 ± 0.18 mg/g and 10.97 ± 0.173 mg/g) and recovery (48.41 ± 0.76%) percent over other adsorbents. Experiments on the degrading behavior (40-80 °C) of the recovered Cy3-gal were performed over time, and the first-order kinetic model better explained the obtained data. In conclusion, the study asserts the use of ultrasonication with NADES and XAD-7HP resin for the improved purification of Cy3-gal from the crude extract., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In the context of a circular economy, this study explores the valorization of blueberry pomace (BP) as a source of bioactive compounds using sustainable extraction methods. Microwave-assisted extraction (MAE) and microwave-assisted subcritical water extraction (MASWE) were employed to obtain two distinct fractions: MAE 1° and MASWE 2°. The first extract, MAE 1°, obtained at 80 °C, had a high total anthocyanin content (21.96 mg Cya-3-glu /g extract ), making it suitable as a natural pigment. Additionally, MAE 1° exhibited significant enzyme inhibition, particularly against α-amylase and β-glucosidase, suggesting potential anti-diabetic and anti-viral applications. The second extract, MASWE 2°, obtained at 150 °C, contained a higher total phenolic content (211.73 mg GAE /g extract ) and demonstrated stronger antioxidant activity. MASWE 2° showed greater inhibition of acetylcholinesterase and tyrosinase, indicating its potential for use in Alzheimer's treatment, skincare, or as a food preservative. MASWE 2° exhibited cytotoxicity against HeLa cells and effectively mitigated H 2 O 2 -induced oxidative stress in HaCat cells, with MAE 1° showing similar but less pronounced effects. A tested formulation combining MAE 1° and MASWE 2° extracts in a 3:2 ratio effectively enhanced anthocyanin stability, demonstrating its potential as a heat-stable pigment. The extract characteristics were compared with a conventional method (MeOH-HCl in reflux condition), and the protocol's sustainability was assessed using several green metric tools, which provided insights into its environmental impact and efficiency.

This study aimed to optimize the ultrasound-assisted extraction (UAE) of anthocyanins from oven-dried and freeze-dried Vitis labrusca grape pomace, using acidified water as the solvent. The effects of power density (8.3-16.7 W/mL), pulse interval (0-2 s), and extraction time (1-5 min) on both total and specific anthocyanins were investigated. The findings suggested that acidified water can be a viable alternative to conventional solvents and that oven drying was an effective method for drying the pomace. Using response surface methodology, the study identified power density and extraction time as key factors influencing total anthocyanin content, with extracts reaching contents up to 2.56 mg/g. The analysis using LC-MS identified 14 anthocyanins, while NMR quantified 3 and malvidin diglucoside was generally the most abundant. However, higher power and longer extraction times were found to reduce its content while increasing malvidin monoglucoside content, suggesting ultrasound-induced anthocyanin hydrolysis. In conclusion, this study presents a sustainable method for extracting anthocyanins using acidified water, contributing to the valorization of Vitis labrusca grape pomace for industrial use., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This research aimed to optimize the extraction of anthocyanin from Solanum melongena L. fruits by studying the effects of extraction time, temperature, pH, and solid-to-liquid ratio using response surface methodology. The Box-Behnken design was used to analyze the anthocyanin concentration under different combinations of these parameters. The optimal conditions for anthocyanin extraction were found to be 7.9 h extraction time, 33.63 °C extraction temperature, 5.39 pH of extraction solvent, and 0.32 solid-liquid ratio. The recovery of 88.12 mg·100 g -1 anthocyanin concentration was achieved with 0.53% relative error compared to the output generated through the chemometric model. Statistical analysis revealed a significant effect of the selected parameters on anthocyanin extraction. The extracted anthocyanin was characterized and found to contain delphinidin. These findings suggest that the optimized method can be used for the efficient extraction and characterization of anthocyanins from Solanum melongena L. fruits.

In this work, new sorbents for the purification of anthocyanin-rich extracts were evaluated. Copolymers of 4-vinylpyridine crosslinked with trimethylolpropane trimethacrylate (poly(4VP-co-TRIM)) or 1,4-dimethacryloyloxybenzene (poly(4VP-co-14DMB)) were tested for their potential to capture polyphenols. Copolymers were obtained by seed swelling polymerization in the form of microspheres with permanent porous structure - attractive features of sorbents used for sample purification by dispersive solid phase extraction. The microspheres were characterized by AFM, elemental analysis, SEM, and nitrogen adsorption-desorption method. Their capacity to remove polyphenols was evaluated using spectrophotometry, HPLC-DAD, and LC-MS/MS. For proof-of-concept, the aqueous extracts of berries classified into three different groups regarding their anthocyanin composition (strawberries, raspberries, blackcurrants) were selected. It was found that studied microspheres adsorbed flavonoids more effectively compared to primary secondary amine and graphitized carbon black. Copolymers of 4-vinylpyridine also capture anthocyanins and might be used for the purification of extracts of fruits before LC-MS/MS analysis to reduce the matrix effect., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ilona Sadok, Agnieszka Krzyszczak-Turczyn, Marta Grochowicz have patent “Method of obtaining purified berry fruit extracts and the use of microspheres based on 4-vinylpyridine for the purification of berry fruit extracts”, P.448492 pending to The Patent Office of the Republic of Poland., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Jabuticaba peel, rich in antioxidants, offering health benefits. In this study, the extraction of phenolic compounds from jabuticaba peel using ultrasound-assisted (UA) and their subsequent concentration by nanofiltration (NF) employing a polyamide 200 Da membrane was evaluated. The UA extractions were conducted using the Central Composite Rotatable Design (CCRD) 22 methodology, with independent variables extraction time (11.55 to 138 min) and temperature (16.87 to 53.3 °C), and fixed variables mass to ethanol solution concentration at pH 1.0 (1:25 g/mL), granulometry (1 mm), and ultrasonic power (52.8 W). The maximum concentrations obtained were 700.94 mg CE/100 g for anthocyanins, 945.21 mg QE/100 g for flavonoids, 133.19 mg GAE/g for phenols, and an antioxidant activity IC50 of 24.36 μg/mL. Key phenolic compounds identified included cyanidin-3-glucoside, delphinidin-3-glucoside, and various acids like syringic and gallic. NF successfully concentrated these compounds, enhancing their yield by up to 45%. UA and NF integrate for sustainable extraction., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Recently, deep eutectic solvents (DES) have been extensively researched as a more biocompatible and efficient alternative to conventional solvents for extracting pigments from natural resources. The efficiency of DES extraction for the anthocyanin and carotenoid can be enhanced by microwave-assisted extraction (MAE) and/or ultrasound-assisted extraction (UAE) techniques. Apart from the extraction efficiency, the toxicity and recovery of the pigments and their bioavailability are crucial for potential applications. A plethora of studies have explored the extraction efficiency, toxicity, and recovery of pigments from various natural plant-based matrices using DES. Nevertheless, a detailed review of the deep eutectic solvent extraction of natural pigments has not been reported to date. Additionally, the toxicity, safety, and bioavailability of the extracted pigments, and their potential applications are not thoroughly documented. Therefore, this review is designed to understand the aforementioned concepts in using DES for anthocyanin and carotenoid extraction., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. For the purpose of open access, the author, Ali Ali Redha, has applied a ‘Creative Commons Attribution (CC BY) licence to any Author Accepted Manuscript version arising., (Crown Copyright © 2024. Published by Elsevier Ltd. All rights reserved.)

Extraction of anthocyanins from Lycium ruthenicum Murr. (L. ruthenicum) is a notable challenge in food production, requiring methods that balance efficiency and safety. In this study, we conducted a comparative analysis the extraction of anthocyanins by natural air drying (NAD), vacuum freeze drying (VFD), hot air drying (HAD), and vacuum microwave drying (MVD) combined with ultrasonic-assisted enzymolysis extraction (UAEE). The results demonstrated that the extraction yield and antioxidant activity of anthocyanins were significantly higher in VFD. This phenomenon can be attributed to the modification of raw material's microstructure, leading to an increased extraction yield of specific anthocyanins such as Cyanidin-3-galactoside, Delphinidin chloride, Cyanidin, and Petunidin. According to the pretreatment results, the extraction process of anthocyanins was further optimized. The highest yield (3.16 g/100 g) was obtained in following conditions: 0.24 % pectinase, 48 °C, solid:liquid = 1:21, and 21 min ultrasonic time. This study improves the commercial value and potential application of L. ruthenicum in food industry., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Anthocyanins, as the most critical water-soluble pigments in nature, are widely present in roots, stems, leaves, flowers, fruits, and fruit peels. Many studies have indicated that anthocyanins exhibit various biological activities including antioxidant, anti-inflammatory, anti-tumor, hypoglycemic, vision protection, and anti-aging. Hence, anthocyanins are widely used in food, medicine, and cosmetics. The green and efficient extraction and purification of anthocyanins are an important prerequisite for their further development and utilization. However, the poor stability and low bioavailability of anthocyanins limit their application. Protein, one of the three essential nutrients for the human body, has good biocompatibility and biodegradability. Proteins are commonly used in food processing, but their functional properties need to be improved. Notably, anthocyanins can interact with proteins through covalent and non-covalent means during food processing, which can effectively improve the stability of anthocyanins and enhance their bioavailability. Moreover, the interactions between proteins and anthocyanins can also improve the functional characteristics and enhance the nutritional quality of proteins. Hence, this article systematically reviews the extraction and purification methods for anthocyanins. Moreover, this review also systematically summarizes the effect of the interactions between anthocyanins and proteins on the bioavailability of anthocyanins and their impact on protein properties. Furthermore, we also introduce the application of the interaction between anthocyanins and proteins. The findings can provide a theoretical reference for the application of anthocyanins and proteins in food deep processing.

Grape pomace is the main by-product obtained from wine production that is still enriched in bioactive compounds. Within a framework of waste/by-product reuse through a sustainable approach, various green methods were utilized in this work to recover anthocyanins from the pomace resulting from "Sangiovese" grape vinification. Ultrasound- and Microwave-Assisted Extractions (UAE and MAE) were coupled with the use of green solvents, such as acidified water, an ethanol/water mixture, and Natural Deep Eutectic Solvents (NaDES), and their efficacy was compared with that of a conventional method based on a methanol/acidified water mixture. The Total Anthocyanin Index ranged from 36.9 to 75.2 mg/g DW for UAE, and from 54.4 to 99.6 mg/g DW for MAE, while resulting in 47.1 mg/g DW for conventional extraction. A Design of Experiments (DoE) approach was applied to MAE, the most efficient technique. Temperature, time, and the solid-to-liquid ratio were set as X variables, while malvidin-3- O -glucoside content and antioxidant activity were used as response variables, measured by High-Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay, respectively. The correlation between temperature and time and the antioxidant activity of the extract was positive, while it was found to be negative when considering malvidin-3- O -glucoside concentration as a response variable. Thus, the optimal conditions in temperature, time and solid-to-liquid ratio were different depending on the chosen variable. The results underline the importance of selecting an accurate response when using the response surface methodology approach.

A dynamic compressed fluid-based separation process combining carbon dioxide and ethanol was explored to isolate portisins previously hemi-synthesized from blueberry surplus anthocyanins. The influence of process parameters such as pressure (100-500 bar), temperature (40-60 °C), and ethanol content in the compressed fluid mixture (20-50 wt%) on extraction yield, portisins yield, and portisins content in the extract was investigated. The two-step isolation process includes (1) a first step at 100 bar, 60 °C, and 20 wt% ethanol content in the compressed fluid mixture to remove the low polarity compounds; and (2) a second step at 500 bar, 40 °C, and 100 wt% ethanol to recover portisins, resulting in a 1.5-fold increase in portisins content. The performance of the two-step separation process was compared to centrifugal partitional chromatography and conventional reverse phase liquid chromatography already reported in terms of portisins content in the extract, process throughput, process efficiency, and total solvent used. The two-step separation process decreased the total solvent used, although with a decrease in the throughput and efficiency. Nevertheless, the choice of the best separation technology depends on the application, as these techniques result in different portisins purities. Overall, this study contributed to a scalable and more sustainable process for natural colorant production, specifically focusing on blue pigments, with several industrial applications.

Saffron ( Crocus sativus ) floral by-products are a source of phenolic compounds that can be recovered and used in the nutraceutical, pharmaceutical, or cosmetic industries. This study aimed to evaluate the phenolic compounds' extraction using green extraction techniques (GETs) in saffron floral by-products and to explore the influence of selected extraction techniques on the phytochemical composition of the extracts. Specifically, ultrasound-assisted extraction (UAE), subcritical water extraction (SWE), and deep eutectic solvents extraction (DESE) were used. Phenolic compounds were identified with (HR) LC-ESI-QTOF MS/MS analysis, and the quantitative analysis was performed with HPLC-PDA. Concerning the extraction techniques, UAE showed the highest amount for both anthocyanins and flavonoids with 50:50% v / v ethanol/water as solvent (93.43 ± 4.67 mg/g of dry plant, dp). Among SWE, extraction with 96% ethanol and t = 125 °C gave the best quantitative results. The 16 different solvent mixtures used for the DESE showed the highest amount of flavonoids (110.95 ± 5.55-73.25 ± 3.66 mg/g dp), while anthocyanins were better extracted with choline chloride:butane-1,4-diol (16.0 ± 0.80 mg/g dp). Consequently, GETs can be employed to extract the bioactive compounds from saffron floral by-products, implementing recycling and reduction of waste and fitting into the broader circular economy discussion.

In aquatic settings, radioactive iodine from nuclear waste can exist as iodate (IO 3 - ). This study explored the efficiency and mechanism of IO 3 - adsorption by minimally modified anthocyanin-based adsorbents. Pomegranate peels and mangosteen pericarps were selected from an initial screening test and could remove over 70% of 10 mg/L IO 3 - . The adsorbents yielded adsorption capacity (q) of 9.59 mg/g and 2.31 mg/g, respectively, at room temperature. At 5 °C, q values increased to 14.5 and 5.13 mg/g, respectively. Pomegranate peels showed superior performance, with approximately 4 times the anthocyanin content of mangosteen pericarps. Both adsorbents took 120 min to reach adsorption equilibrium, and no desorption was observed after 8 days (I-131 half-time). Confirmation of physisorption was indicated by the fit of the pseudo-first-order reaction model, negative entropy (exothermic), and negative activation energy (Arrhenius equation). IO 3 - inclusion was confirmed through adsorbent surface modifications in scanning electron microscope images, the increased iodine content post-adsorption in energy-dispersive X-ray spectroscopy analysis, and alterations in peaks corresponding to anthocyanin-related functional groups in Fourier transform infrared spectroscopy analysis. X-ray absorption near-edge spectroscopy at 4564.54 eV showed that iodine was retained in the form of IO 3 - . Through the computational analysis, electrostatic forces, hydrogen bonds, and π-halogen interactions were deduced as mechanisms of IO 3 - adsorption by anthocyanin-based adsorbents. Anthocyanin-rich fruit wastes emerged as sustainable materials for eliminating IO 3 - from water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Efficient extraction of natural pigments is a key focus in enhancing the utilization of by-products for applications in the food industry. In this study, an enzymatic extraction method using Pectinex Ultra SP-L, Pectinex XXL, Novoshape, and Celluclast was used to investigate natural pigment production from the pomace of aronia, a commercially important plant. The method's performance was monitored using high-performance liquid chromatography with diode-array detection by measuring total and individual anthocyanin levels. Pectinex XXL (0.5%) yielded the highest total anthocyanin extraction (2082.41 ± 85.69 mg/100 g) in the single enzyme treatment, followed by Pectinex Ultra SP-L (0.05%), Celluclast (0.01%), and Novoshape (0.1%). Combining Pectinex XXL (0.25%) with Celluclast (0.01%) increased the extraction ratio of total anthocyanins (2 323.04 ± 61.32 mg/100 g) by ∼50.7% compared with that obtained using the solvent extraction method. This study demonstrated an effective enzymatic extraction method for application in the food industry., (© The Author(s) 2024. Published by Oxford University Press on behalf of Japan Society for Bioscience, Biotechnology, and Agrochemistry.)

Anthocyanins (ANCs), a kind of natural pigments, are widely present in food substrates. Evidence has shown that ANCs can promote health in terms of anti-oxidation, anti-tumor, and anti-inflammation. However, the oxidative stability of ANCs limits accurate quantitation and analysis. Therefore, faster, more accurate, and highly sensitive extraction and determination methods are necessary for understanding the role of ANCs in medicine and food. This review presents an updated overview of pretreatment and detection techniques for ANCs in various food substrates since 2015. Liquid-liquid extraction and various green solvent extraction methods, such as accelerated solvents extraction, deep eutectic solvents extraction, ionic liquids extraction, and supercritical fluid extraction, are commonly used pretreatment methods for extraction and purification of ANCs. Liquid chromatography coupled with different detectors (tandem mass spectrometry and UV detectors) and spectrophotometry methods are some of the determination methods for ANC. This study has updated, compared, and discussed different pretreatment and analysis methods. Moreover, the advanced methods and development prospects in this field are comprehensively summarized, which can provide references for further utilization of ANCs.

Context: Delphinidin-3- O -glucoside (DP) is a bioactive compound of Hibiscus sabdariffa L. (Malvaceae) (Roselle) calyces and exerts endothelial protection and lipid-lowering activities, which provided a basis for the prevention and treatment of cardiovascular diseases., Objectives: To investigate the therapeutic effects of DP against atherosclerosis., Materials and Methods: A rabbit model of atherosclerosis (AS) was established by 12 weeks of a high-fat diet (HFD). The rabbits were divided into five groups: control, AS, simvastatin (4 mg/kg), and two DP groups (10 and 20 mg/kg). After treatment with DP or simvastatin by oral gavage for 12 weeks, the lipid profiles were measured. Histopathological assessment of the aorta was performed by H&E staining. Oxidative stress and inflammation-related markers were analyzed by ELISA kit and real-time RT-PCR., Results: DP (20 mg/kg) decreased serum TG (2.36 ± 0.66 vs. 4.33 ± 0.27 mmol/L for the AS group), TC, LDL-C, and HDL-C (all p  < 0.05). DP (20 mg/kg) also reduced lipid levels in the liver and aorta. DP (20 mg/kg) down-regulated the mRNA levels of IL-6, VCAM-1, and NF-κB and up-regulated the mRNA levels of GSH-PX and SOD1., Conclusions: This study proved that DP alleviated the HFD-induced oxidative stress and inflammation in atherosclerosis rabbits. These results provided the scientific basis for developing novel therapies.

Lycium ruthenicum Murr. fruit (LRF) is an edible berry known for its rich anthocyanin content. Our previous study has shown that LRF-derived anthocyanins have neuroprotective effects in rats, which may be due to their effective antioxidant activity. Therefore, this study performed online HPLC-DPPH screening as a bioactivity-guided method for the preparative separation of anthocyanins from LRF. Finally, the main fraction was isolated and identified as petunidin-3,5- O -diglucoside (Pn3G5G). Pn3G5G exhibited strong antioxidant capacity during DPPH and ABTS free radical scavenge assays. Furthermore, Pn3G5G exhibited protective effects on N ε -carboxymethyllysine (CML)-treated Neuro-2a cells by enhancing cell viability in a dose-dependent manner. CML-induced apoptosis was also reduced by Pn3G5G potentially by suppressing oxidative stress and inflammation. More importantly, Pn3G5G significantly improved cognitive impairment, neuroinflammation and neuronal apoptosis in D-galactose-induced aging mice. The result suggests the development of Pn3G5G as a healthcare product or a potent dietary supplement with antioxidant and neuroprotective effects.

Anthocyanins are natural pigments displaying different attractive colors ranging from red, violet, to blue. These pigments present health benefits that increased their use in food, nutraceuticals, and the cosmetic industry. However, anthocyanins are mainly extracted through conventional methods that are time-consuming and involve the use of organic solvents. Moreover, the chemical diversity of the obtained complex extracts make the downstream purification step challenging. Therefore, the growing demand of these high-value pigments has stimulated the interest in designing new, safe, cost-effective, and tunable strategies for their extraction and purification. The current review focuses on the potential application of compressed fluid-based (such as subcritical and supercritical fluid extraction and pressurized liquid extraction) and deep eutectic solvents-based extraction methods for the recovery of anthocyanins. In addition, an updated review of the application of counter-current chromatography for anthocyanins purification is provided as a faster and cost-effective alternative to preparative-scale HPLC.

In this paper, biological investigations and a high-resolution UPLC-PDA-ESI-qTOF-HRMS technique were employed for Brassica oleracea L. var. capitata f. rubra DC. (red cabbage) of the family Brassicaceae (Cruciferae), cultivated in Egypt, for the first time. The positive ionization mode is usually performed to identify anthocyanins. However, this technique cannot differentiate between anthocyanins and corresponding non-anthocyanin polyphenols. Thus, the negative ionization mode was also used, as it provided a series of characteristic ions for the MS analysis of anthocyanins. This helped in identifying five kaempferol derivatives for the first time in red cabbage, as well as nine-previously reported-anthocyanins. For the biological investigations, the acidified methanolic extract of fresh leaves and the methanolic extract of air-dried powdered leaves were examined for their antioxidant, antimicrobial, and anticancer activities. The freshly prepared phenolic extract was proven to be more biologically potent. Statistical significance was determined for its anticancer activity in comparison with standard doxorubicin.

Age-related macular degeneration (AMD) is one of the major causes of blindness in elderly populations. However, the dry form of AMD has lack of effective treatments. The fruits of Aronia melanocarpa are rich in anthocyanins. In this study, the protective effects of aronia fruit extract on rat retina were investigated using a NaIO 3 -induced dry AMD model. Full-field electroretinograms (ERGs) showed that b-wave amplitudes were significantly decreased and the retina structures were disordered in the model. The extract treatment alleviated the injuries. The b-wave amplitudes increased 61.5% in Scotopic 0.01ERG, 122.0% in Photopic 3.0ERG, and 106.8% in Photopic 3.0 flicker; the retina structure disorder was improved with the thickness of outer nuclear layer increasing by 44.1%; and the malonaldehyde level was significantly reduced in extract-treated rat retinas compared to the model. The proteomics analysis showed the expressions of five crystallin proteins, α-crystallin A chain, β-crystallin B2, β-crystallin A3, α-crystallin B chain, and γ-crystallin S, which protect retina ganglion cells, were increased by 7.38-, 7.74-, 15.30-, 4.86-, and 9.14-fold, respectively, in the extract treatment compared to the control, which was also confirmed by immunoblotting. The results suggest that aronia fruit extract, probably due to its anthocyanins, could protect the rat retina by alleviating oxidative damages and by upregulating the crystallin proteins to protect its nerve system.

Variability of secondary metabolites in edible (peel and pulp) and inedible (seeds) parts of three pitanga varieties, red, red-orange and purple, was investigated during the maturation process. Hydrolysable tannins, anthocyanins, and flavonoids were quantified by HPLC/DAD and carotenoids by absorbance. Peel/pulp showed greater complexity of constituents (carotenoids, anthocyanins, flavonoids, and hydrolysable tannins), while only tannins were identified in seeds, but in quantities of 10 to 100 times greater. The red-orange variety showed the highest levels of phenolic compounds in seeds and peel/pulp, except anthocyanins. The analysis of the principal response curves showed that the pitanga biotype has greater influence on metabolite variation than ripening stages. During peel/pulp maturation, a reduction in the levels of flavonoids and tannins contrasted with an increase in carotenoids and cyanidin-3-O-glucoside in all varieties, whereas in the seeds oenothein B, the major tannin, increased up to 1.32 g/100 g fresh weight. Such marked differences between fruit parts demonstrate that the seeds in stages E3 and E4 are a source of hydrolysable tannins, compounds known for their antitumor activity, while peel/pulp of all varieties in the ripe stage provide natural antioxidants, such as carotenoids and flavonoids. Lastly, the purple biotype can be a rich source of the cyanidin-3-O-glucoside pigment a potent bioactive compound., (© 2021 Wiley-VHCA AG, Zurich, Switzerland.)

Anthocyanins from flowers of the butterfly pea ( Clitoria ternatea L.) are promising edible blue food colorants. Food processing often faces extreme pHs and temperatures, which greatly affects the color and nutritional values of anthocyanins. This study explored the color, spectra, storage stability, and antioxidant properties of C. ternatea anthocyanin extract (CTAE) at different pHs. The color and absorption spectra of CTAEs at a pH of 0.5-13 were shown, with their underlying structures analyzed. Then, the storage stability of CTAEs were explored under a combination of pHs and temperatures. The stability of CTAE declines with the increase in temperature, and it can be stored stably for months at 4 °C. CTAEs also bear much resistance to acidic and alkaline conditions but exhibit higher thermal stability at pH 7 (blue) than at pH 0.5 (magenta) or pH 10 (blue-green), which is a great advantage in food making. Antioxidant abilities for flower extracts from the butterfly pea were high at pH 4-7, as assessed by DPPH free radical scavenging assays, and decreased sharply when the pH value exceeded 7. The above results provide a theoretical basis for the application of butterfly pea flowers and imply their great prospect in the food industry.

Mulberry fruits are rich sources of anthocyanins that exhibit beneficial biological activity. These anthocyanins become instable in an aqueous media, leading to their low bioavailability. In this study, a colloidal dispersion was produced by processing mulberry samples with hot-melt extrusion. In this process, hydrophilic polymer matrices were used to disperse the compound in an aqueous media. Mulberry samples were processed with hot-melt extrusion and in the presence of an ionization agent and sodium alginate to form mulberry-extrudate solid formulations. The particle size of mulberry-extrudate solid formulations decreased, while the total phenol content, the total anthocyanin content, and solubility increased. Fourier transform infrared spectroscopy (FT-IR) revealed that mulberry-extrudate solid formulations now contained new functional groups, such as -COOH group. We investigated whether mulberry-extrudate solid formulations had a positive impact on the stability of anthocyanins. The non-extrudate mulberry sample and mulberry-extrudate solid formulations were incubated with a simulated gastric fluid system and an intestinal fluid system. The number of released anthocyanins was determined with HPLC. We found that anthocyanins were released rapidly from non-extrudate mulberry extract. Mulberry-extrudate solid formulations contained a large number of available anthocyanins even after being incubated for 180 min in the intestinal fluid system. Thus, hot-melt extrusion enhanced water solubility and stability of anthocyanins with the prolonged release.

Anthocyanins are the largest group of polyphenolic pigments in the plant kingdom. These non-toxic, water-soluble compounds are responsible for the pink, red, purple, violet, and blue colors of fruits, vegetables, and flowers. Anthocyanins are widely used in the production of food, cosmetic and textile products, in the latter case to replace synthetic dyes with natural and sustainable alternatives. Here, we describe an environmentally benign method for the extraction of anthocyanins from red chicory and their characterization by HPLC-DAD and UPLC-MS. The protocol does not require hazardous solvents or chemicals and relies on a simple and scalable procedure that can be applied to red chicory waste streams for anthocyanin extraction. The extracted anthocyanins were characterized for stability over time and for their textile dyeing properties, achieving good values for washing fastness and, as expected, a pink-to-green color change that is reversible and can therefore be exploited in the fashion industry.

The development of nanomedicines to modulate the mitochondrial function is a great scientific challenge since mitochondrial dysfunction is a pathological hallmark of many chronic diseases, including degenerative brain pathologies like Parkinson's and Alzheimer's diseases. To address this challenge, the mitochondriotropic features of the elderberry anthocyanin-enriched extract (Sambucus nigra) were combined with the self-assembling properties of the membrane polar lipids from Codium tomentosum in an innovative SC-Nanophytosomes formulation. Membrane polar lipids, obtained by a new procedure as chlorophyll-free extract, are characterized by 26% of non-phosphorus polar lipids and 74% of phospholipids (dominated by anionic lipids) containing a high degree of polyunsaturated fatty acids. The anthocyanin-enriched extract is dominated by a mixture of four cyanidin-glycosides, representing about 86% of their phenolic content. SC-Nanophytosomes engineered with 600 µM algae membrane polar lipids and 0.5 mg/L of the anthocyanin-enriched extract are nanosized vesicles (diameter =108.74 ± 24.74 nm) with a negative surface charge (Zeta potential = -46.93 ± 6.63 mV) that exhibit stability during storage at 4 ºC. In vitro assays with SH-SY5Y cells showed that SC-Nanophytosomes have the competence to target mitochondria, improving the mitochondrial respiratory chain complexes I and II and preserving the mitochondrial membrane potential in the presence of rotenone. Additionally, SC-Nanophytosomes protect SH-SY5Y cells against the toxicity induced by rotenone or glutamate. Green-fluorescent labeled SC-Nanophytosomes were used to reveal that they are mainly internalized by cells via caveola-mediated endocytosis, escape from endosome and reach the cytoplasm organelles, including mitochondria. Overall, data indicate that SC-Nanophytosomes have the potential to support a mitochondria-targeted therapy for neurodegenerative diseases., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

To extract anthocyanins from wild Prunus cerasifera fruit peel and to identify the main compositions. The effects of extraction solvent, solid-to-liquid ratio, extraction time and extraction temperature on the extraction rate of anthocyanins were determined using colorimetric method, differential spectrophotometry and L9 (34) orthogonal experiment. The structure of the anthocyanins extracted from wild Prunus cerasifera fruit peel was preliminarily identified by liquid chromatography-electrospray ionization-tandem mass spectrometry. And hydroxyl radical scavenging rate and DPPH radical scavenging rate were used to investigate the antioxidant activity of Xinjiang cherry anthocyanin in vitro. The highest extraction rate of anthocyanins was acquired under the conditions including 1% HCl-methanol, solid-to-liquid ratio =1:5, extraction temperature 55°C and extraction time 80 minutes. Liquid chromatography-electrospray ionization-tandem mass spectrometry results showed that the main compositions of anthocyanins were cyanidin 3-galactoside, cyanidin 3-glucoside, cyanidin 3-rutinoside and cyanidin 3-xyloside. The results of antioxidant test showed that Xinjiang cherry anthocyanin had certain scavenging effect on 1, 1-diphenyl-2-picrylphenylhydrazine (DPPH•) and hydroxyl radical (•OH), but was weaker than Vc. Findings from this study provide evidence for extraction process and composition identification of anthocyanins from Xinjiang wild Prunus cerasifera fruit peel.

Lycium ruthenicum Murray is widely used in traditional Chinese medicine and is believed to have antimicrobial, antioxidant, and anti-fatigue effects. Anthocyanins are considered to be one of the main active components. The previous work by our research team found that the anthocyanins in Lycium ruthenicum extract (ALRM) produce a stable anti-anxiety effect. The mechanisms of action include reducing the level of corticotropin-releasing factor (CRF) as well as regulating extracellular signal-regulated kinase/mitogen activation, protein kinase (ERK/MAPK) pathways, and others, all of which are related to the mechanisms of nicotine addiction. To investigate the effects of ALRM on anxiety and craving behavior after nicotine withdrawal, the components of ALRM were analyzed using the UPLC-Orbitrap MS method. The effects of ALRM on anxiety behavior induced by nicotine withdrawal were investigated in mice using the elevated plus maze (EPM) and light-dark box (LDB) tests. The effects of ALRM on craving behavior after nicotine withdrawal were further investigated using the conditional place preference (CPP) test. The EPM and LDB tests demonstrated that ALRM could alleviate the anxiety behavior induced by nicotine withdrawal and reduce nicotine craving in mice. Based on the identified ALRM components, the network pharmacology method was used to predict the mechanism of ALRM alleviating anxiety after nicotine withdrawal in mice. It was speculated that ALRM was involved in the production and transmission of dopamine, choline, and other nervous system functions and exhibited a potential role in treating nicotine addiction., (Copyright © 2021 Elsevier B.V. All rights reserved.)

As phytochemicals, anthocyanins are not only responsible for the diverse colors in nature, but are associated with broad-spectrum health-promoting effects for human beings. Pomegranate is abundant in anthocyanins which possess high antioxidant capacities. However, the pomegranate anthocyanins profile and their contributions to antioxidant capacities are not fully depicted. The purpose of this article is to review anthocyanins from pomegranate as important antioxidants. Total anthocyanin content (TAC) and six major components vary greatly with intrinsic and extrinsic factors. In pomegranate, anthocyanins mainly acted as primary antioxidants, while their action as secondary antioxidants were not conclusive. The antioxidant potentials of anthocyanins were significantly affected by factors especially chemical structure and detection assays in vitro. The current knowledge may provide insights into potential applications for pomegranate anthocyanins based on their antioxidant activities., (© 2021 Wiley-VHCA AG, Zurich, Switzerland.)

The current work aims to prepare biologically active and pH responsive smart films based on Chitosan (CS)/Methylcellulose (MC) matrix integrated with Phyllanthus reticulatus (PR) ripen fruit anthocyanin. The prepared smart films (CMPR) were fabricated through a cost-effective solvent casting technique. The existences of secondary interactions were confirmed by the FT-IR analysis. The smooth SEM images revealed the miscibility and compatibility of the CS/MC matrix with PR anthocyanin. The incorporation of PR anthocyanin significantly blocked the UV light transmission of the CS/MC films while slight decrease in the transparency was observed. The water solubility, moisture retention capacity, and water vapor transmission rate were significantly enhanced with an increase in the PR anthocyanin content. Additionally, the prepared CMPR smart films showed pink color in acidic pH while yellowish in basic pH solution and further exhibited strong antioxidant activity as well as antibacterial activity against the common foodborne pathogens such as S. aureus, P. aeruginosa, and E. coli. The CMPR smart film also displayed potential result for monitoring the fish fillet freshness at room temperature. The results proclaim that the prepared CMPR smart films could be utilized for quality assurance as well as shelf life extension of the marine food products., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Yellow to red colored betalains are a chemotaxonomic feature of Caryophyllales, while in most other plant taxa, anthocyanins are responsible for these colors. The carnivorous plant family Nepenthaceae belongs to Caryophyllales; here, red-pigmented tissues seem to attract insect prey. Strikingly, the chemical nature of red color in Nepenthes has never been elucidated. Although belonging to Caryophyllales, in Nepenthes, some molecular evidence supports the presence of anthocyanins rather than betalains. However, there was previously no direct chemical proof of this. Using ultra-high-performance liquid chromatography-electrospray ionization-high-resolution mass spectrometry, we identified cyanidin glycosides in Nepenthes species and tissues. Further, we reveal the existence of a complete set of constitutively expressed anthocyanin biosynthetic genes in Nepenthes. Thus, here we finally conclude the long-term open question regarding red pigmentation in Nepenthaceae., (© 2021 The Authors. FEBS Open Bio published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

Mulberry (Morus alba L.) fruit (MF) is a rich source of functional compounds, such as anthocyanin. However, during solvent extraction, these compounds are not fully dispersed into the substrate, leading to incomplete extraction. Moreover, raw MF rapidly ripens and deteriorates after harvesting; hence, innovative methods to process MF are needed. Here, a pectinase-assisted extraction method is developed to liberate polyphenols and anthocyanins from cell wall matrices in MF. We optimized the procedure to maximize water solubility index (WSI), total phenolic (TP) content, and total anthocyanin (TA) content using a central composite design to perform a response surface methodology (RSM) analysis. The optimal conditions predicted by the RSM were a 1:5 w/v material/water ratio with 3.5% pectinase (v/w) and 1.5% citric acid (w/w) for 113 min at 50°C. Under these conditions, the WSI, TP, and TA were significantly higher compared with those in the untreated control. The results well matched (within 5% differences) with the predicted RSM values. Furthermore, metabolite analysis revealed that the levels of cyanidin-3-O-glucoside, delphinidin hexoside, and quercetin were higher in pectinase-assisted MF extraction compared with the untreated control. This work demonstrated that pectinase-assisted extraction using citric acid could be an efficient technique to enhance the value of MF and its potential applications in the food industry. PRACTICAL APPLICATION: A pectinase-assisted extraction method was optimized to enhance the WSI, TP, and TA yields from MF extracts. The optimal conditions were predicted to be 1:5 w/v material/water ratio, 3.5% pectinase (v/w), and 1.5% CA (w/w) with a 113 min reaction time at 50°C. Under these conditions, WSI, TP, and TA were significantly increased compared with the untreated control. These results suggested the potential of mulberry plants for use in the food industry via the development of a simple, efficient process to extract functional compounds from MF., (© 2021 Institute of Food Technologists®.)

The effect of the anthocyanin cyanidin-3-O-glucoside (C3G) and its main gastrointestinal metabolites (PCA and PGA) on the binding of AFB 1 and HSA were studied via spectrometry. C3G is relatively stable in the gastric environment, and the intestinal environment promotes its metabolism into PCA and PGA. Binary fluorescence experiments showed that both AFB 1 and C3G, including PCA and PGA, can react with HSA. AFB 1 , C3G and PCA can bind at site I and site II of HSA; PGA binds at site II. The presence of C3G/PCA/PGA inhibits the degree of quenching. C3G/PCA does not change the quenching mechanism; it is still static quenching; however, dynamic quenching occurs in the (AFB 1 -HSA)-PGA system. In addition, the apparent binding constant and number of binding sites of AFB 1 -HSA also diminish to different degrees. C3G and its metabolites (PCA and PGA) interfere with the interaction between AFB 1 and HSA, and can reduce AFB 1 transport at pH 7.4 in vitro. Abbreviations: C3G: cyanidin-3-O-glucoside; M: metabolite; PCA: protocatechuic acid; PGA: phloroglucinol aldehyde; AFB 1 : aflatoxin B 1 ; HSA: human serum albumin.

An anthocyanin-rich extract was obtained from Nitraria tangutorum Bobr. fruit, namely ANF, and its composition, antioxidant and neuroprotective effects were studied. Nine anthocyanins were identified from the ANF using UPLC-Triple-TOF/MS analysis, and cyanidin-3-[2''-(6'''-coumaroyl)-glucosyl]-glucoside (C3G) is the most abundant anthocyanin (87.06%). ANF exhibited high ferric reducing antioxidant power (FRAP) and ABTS radical scavenging activity. The online HPLC-DPPH screening revealed that C3G contributed the highest antioxidant capacity. ANF showed potential neuroprotective effects by relieving d-Galactose-induced memory deficits, reducing overexpression of receptor for advanced glycation end products (RAGE) and amyloid-beta42 (Aβ42) in the hippocampus of rats. Besides, ANF could inhibit oxidative stress by reducing the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) in the hippocampus, while elevating amounts of total superoxide dismutase (T-SOD) and glutathione (GSH) in the serum of rats. Thus, ANF has great potential in the development of food and health products related to antioxidant and neuroprotective effects., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Phenolic compounds from plant sources have significant health-promoting properties and are known to be an integral part of folk and herbal medicines. Consumption of phenolics is known to alleviate the risk of various lifestyle diseases including cancer, cardiovascular, diabetes, and Alzheimer's. In this context, numerous plant crops have been explored and characterized based on phenolic compounds for their use as supplements, nutraceutical, and pharmaceuticals. The present review highlights some important source of bioactive phenolic compounds and novel technologies for their efficient extraction. These techniques include the use of microwave, ultrasound, and supercritical methods. Besides, the review will also highlight the use of response surface methodology (RSM) as a statistical tool for optimizing the recoveries of the phenolic bioactives from plant-based matrices., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The aim of the study was to investigate changes in the content of biologically active compounds during the fermentation and aging of natural meads with the addition of three Cornelian cherry juices from three cultivars: 'Koralovyi', 'Podolski' and 'Yantarnyi', in the amount of 10% v / v . After the fermentation process the content of gallic and ellagic acids significantly increased, in relation to wort. Whereas the greatest losses were observed among unstable anthocyanins. The three-month aging process also reduced the content of the analyzed compounds except for ellagic acid, the content of which increased by up to 90%. The content of biologically active compounds, including iridoids and antioxidant phenolics, are constantly changing in the process of fermentation and aging of fruit meads. The studies proved that the addition of Cornelian cherry juice allows significantly enriched classic meads with new biologically active compounds, such as: exceptional iridoids (loganic acid, cornuside, loganine, sweroside), flavonols, phenolic acids and anthocyanins.

Passion fruit rind is a waste product from the beverage industry that is rich in anthocyanins that can be potentially applied as a natural colorant. However, the inherent instability of anthocyanins causes rapid discoloration. In this study, the cyanidin-3-glucoside (C-3-G) in passion fruit rind was extracted using 50% ethanol and converted into nonbleachable pigments by reaction with Oolong tea extracts and acetaldehyde. Reactions over 70 days formed high concentrations of stable nonbleachable pigments (3.07-6.68 absorbance unit [A.U.], in total) such as pyranoanthocyanins, as well as oligomeric and polymeric pigments with ethyl-linked bridges. In C-3-G and acetaldehyde reaction, positive relations were found among acetaldehyde concentration, color density, and nonbleachable pigment concentrations. As for reactions with C-3-G and Oolong tea extract combined with acetaldehyde, greater color density and greater concentrations of nonbleachable pigments (10.80-12.34, 4.25-4.40 A.U., respectively) were formed compared with acetaldehyde alone. In addition, the antioxidant capabilities of the extracts were enhanced after reaction with Oolong tea extracts. The results of this study show a useful method to enhance the stability of anthocyanins from passion fruit rind and also provide greater economic value to this waste product. PRACTICAL APPLICATION: Ripened passion fruits contain a high concentration of anthocyanins in their rind. These anthocyanins can be optimally extracted by ultrasonic assisted solvent extraction to provide stable pigments by inducing acetaldehyde (a volatile compound often found in foods and beverages) into the anthocyanins. These stable pigments have a greater reddish hue in solution than the anthocyanin extracted from the rind and are more stable over a greater pH range. In addition, these stable pigments can be potentially used as colorant throughout the food and cosmetic industry to provide high economical values., (© 2021 Institute of Food Technologists®.)

Two common extraction solvent systems, namely acidified aqueous methanol and acidified aqueous acetone, were used to extract blackberry phenolics, and the antioxidant properties of the recovered extracts were compared. The crude extracts were fractionated into low- and high-molecular-weight phenolics by Sephadex LH-20 column chromatography. The hydrophilic-oxygen radical absorbance capacity (H-ORAC FL ), ferric reducing antioxidant power (FRAP), and the cellular antioxidant activity (CAA) assays were employed as indices to assess antioxidant capacity of the extracts and their respective fractions. The methanolic solvent system displayed a greater efficiency at extracting anthocyanin and flavonol constituents from the blackberries, while the acetonic solvent system was better at extracting flavan-3-ols and tannins. Anthocyanins were the dominant phenolic class found in the blackberries with 138.7 ± 9.8 mg C3G eq./100 g f.w. when using methanol as the extractant and 114.6 ± 3.4 mg C3G eq./100 g f.w. when using acetone. In terms of overall antioxidant capacity of blackberry phenolics, the acetonic solvent system was superior. Though present only as a small percentage of the total phenolics in each crude extract, the flavan-3-ols (42.37 ± 2.44 and 51.44 ± 3.15 mg/100 g f.w. in MLF and ALF, respectively) and ellagitannins (5.15 ± 0.78 and 9.31 ± 0.63 mg/100 g f.w. in MHF and AHF, respectively) appear to account for the differences in the observed antioxidant activity between the two solvent systems.

Usually, wine-making by-products are discarded, presenting a significant environmental impact. However, they can be used as a source of bioactive compounds. Moreover, consumers' increasing demand for naturally nutritious and healthy products requires new formulations and food product improvement, together with sustainable, environmentally friendly extraction methods. Thus, this work aimed to compare ohmic heating (OH) with conventional methodology (CONV), using food-grade solvents, mainly water, compared to standard methanol extraction of anthocyanins. No significant differences were found between the CONV and OH for total phenolic compounds, which were 2.84 ± 0.037 and 3.28 ± 0.46 mg/g DW gallic acid equivalent, respectively. The same tendency was found for antioxidant capacity, where CONV and OH presented values of 2.02 ± 0.007 g/100 g and 2.34 ± 0.066 g/100 g ascorbic acid equivalent, respectively. The major anthocyanins identified were malvidin-3- O -acetylglucoside, delphinidin-3- O -glucoside, petunidine-3- O -glucoside, cyanidin-3- O -glucoside, and peonidine-3- O -glucoside. These extracts displayed antimicrobial potential against microorganisms such as Yersinia enterocolitica , Pseudomonas aeruginosa , Salmonella enteritidis , methicillin-sensitive Staphylococcus aureus , a methicillin-resistant Staph. aureus (MRSA), and Bacillus cereus . In conclusion, OH provides similar recovery yields with reduced treatment times, less energy consumption, and no need for organic solvents (green extraction routes). Thus, OH combined with water and citric acid allows a safe anthocyanin extraction from grape by-products, thus avoiding the use of toxic solvents such as methanol, and with high biological potential, including antimicrobial and antioxidant activity.

Background: Skin cell walls modulate anthocyanin and tannin extraction from grape skins. However, relationships between the composition of alcohol-insoluble cell wall solids (AIS) and extraction are still unclear. Our objectives were to characterize the impact of variety, berry size and ripeness on skin AIS composition (polysaccharides, proteins) and polyphenol extraction during maceration., Results: Grape skin composition and its impact on polyphenol extraction was compared for two varieties - Carignan and Grenache - with skins of berries sorted according to their size and density. Extractions were performed under model wine-like maceration conditions. Fresh skins had similar content of polymeric tannins, but strongly differed in their anthocyanin content (higher in Carignan and in the ripest berries) and composition (higher proportions in coumaroylated anthocyanins in Carignan). Anthocyanin extraction was proportionally much higher in Grenache, which was not just related to the Carignan's higher levels in coumaroylated anthocyanins. Chemical reactions decreased anthocyanin concentrations in solution for both varieties. Tannin extraction for Grenache was slightly higher and faster than for Carignan. Skin AISs differed slightly between the two varieties in their carbohydrate composition and protein content, but not between modalities. Polyphenol analyses in the precipitates evidenced at the end of the maceration and in residual skins highlighted differences between the two varieties and between berries with different ripeness., Conclusion: Structural information on the cell wall network and on its changes during maceration, along with a better understanding of the chemical reactions of anthocyanins and tannins, is needed to better relate grape and wine polyphenol composition. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.)

Enzymatic lipophilization is an important process to extend the use of anthocyanins in lipidic media. In this work delphinidin 3-O-sambubioside (Dp3sam) isolated from Hibiscus sabdariffa L. flower was esterified with octanoic acid using Candida antarctica lipase B. The physical-chemical properties of the new lipophilic pigment were studied by UV-vis spectroscopy. Dp3sam with chloride, acetate and formate as counter ions were employed to study the lipophilization reaction. The hydrolysis of the reagent was avoided with a formate counter ion and the expected product was achieved with a noteworthy change of solubility. 1D and 2D NMR characterization of Dp3sam-C8 confirmed that the lipophilization took place at the primary alcohol of the glucoside moiety. Overall, the Dp3sam-C8 ester presents a stabilization of the quinoidal base (blue color) at neutral or moderate alkaline pH, which foresees a potential use of this pigment as a broad kind of industries on lipo-soluble formulations., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Anthocyanins are naturally occurring phytochemicals that have attracted growing interest from consumers and the food industry due to their multiple biological properties and technological applications. Nevertheless, conventional extraction techniques based on thermal technologies can compromise both the recovery and stability of anthocyanins, reducing their global yield and/or limiting their application in food systems. The current review provides an overview of the main innovative processes (e.g., pulsed electric field, microwave, and ultrasound) used to recover anthocyanins from agri-food waste/by-products and the mechanisms involved in anthocyanin extraction and their impacts on the stability of these compounds. Moreover, trends and perspectives of anthocyanins' applications in food systems, such as antioxidants, natural colorants, preservatives, and active and smart packaging components, are addressed. Challenges behind anthocyanin implementation in food systems are displayed and potential solutions to overcome these drawbacks are proposed.

Aristotelia chilensis (Mol.) Stuntz, also known as maqui, is a plant native to Chile without chemical characterization and quantification of the bioactive compounds present in it. HPLC-UV and HPLC-MS/MS studies have shown the presence, at different concentrations, of phenolic and anthocyanin compounds in fruit and leave extracts of the domesticated maqui clones Luna Nueva, Morena, and Perla Negra. The extracts from leaves and unripe fruits of Luna Nueva and Morena clones significantly inhibit platelet aggregation induced by several agonists; the extracts inhibit platelet granule secretion by decreasing the exposure of P-selectin and CD63 at the platelet membrane. Reactive oxygen species formation in platelets is lower in the presence of maqui extracts. Statistical Pearson analysis supports the levels of phenolic and anthocyanin compounds being responsible for the antiaggregant maqui effects. This work is the first evidence of antiplatelet activity from Aristotelia chilensis giving added value to the use of leaves and unripe fruits from this species., Competing Interests: The authors declare no conflicts of interest.

Wastewaters and by-products generated in the winemaking process are important and inexpensive sources of value-added compounds that can be potentially reused for the development of new products of commercial interest (i.e., functional foods). This research was undertaken in order to evaluate the potential of nanofiltration (NF) membranes in the recovery of anthocyanins and monosaccharides from a clarified Carménère grape marc obtained through a combination of ultrasound-assisted extraction and microfiltration. Three different flat-sheet nanofiltration (NF) membranes, covering the range of molecular weight cut-off (MWCO) from 150 to 800 Da, were evaluated for their productivity as well as for their rejection towards anthocyanins (malvidin-3- O -glucoside, malvidin 3-(acetyl)-glucoside, and malvidin 3-(coumaroyl)-glucoside) and sugars (glucose and fructose) in selected operating conditions. The selected membranes showed differences in their performance in terms of permeate flux and rejection of target compounds. The NFX membrane, with the lowest MWCO (150-300 Da), showed a lower flux decay in comparison to the other investigated membranes. All the membranes showed rejection higher than 99.42% for the quantified anthocyanins. Regarding sugars rejection, the NFX membrane showed the highest rejection for glucose and fructose (100 and 92.60%, respectively), whereas the NFW membrane (MWCO 300-500 Da) was the one with the lowest rejection for these compounds (80.57 and 71.62%, respectively). As a general trend, the tested membranes did not show a preferential rejection of anthocyanins over sugars. Therefore, all tested membranes were suitable for concentration purposes.

Many current food and health trends demand the use of more ecological, sustainable, and environmentally friendly techniques for the extraction of bioactive compounds, including antioxidants. However, extraction yields and final antioxidant activities vary between sources and are highly influenced by the given extraction method and nature and ratio of the employed solvent, especially for total polyphenols, flavonoids, and anthocyanins, which are well recognized as natural antioxidants with food applications. This review focused on the most common extraction techniques and potential antioxidant activity in the food industry for various natural antioxidant sources, such as green tea, rosemary, clove, and oregano. Green extraction techniques have been proven to be far more efficient, environmentally friendly, and economical. In general, these techniques include the use of microwaves, ultrasound, high hydrostatic pressure, pulsed electric fields, enzymes, and deep eutectic solvents, among others. These extraction methods are described here, including their advantages, disadvantages, and applications.

Black rice is considered to be functional food containing anthocyanins as bioactive compounds. This study examined the genomic and proteomic patterns in local black rice from Java Island, Indonesia, with attention to the mechanism of anthocyanin synthesis. Three kinds of black rice from Java Island, including black rice from East Java (BREJ), black rice from Central Java (BRCJ), and black rice from West Java (BRWJ), were studied in comparison to white rice (WREJ) and red rice (RREJ). Genomic profiling was done by simple sequence repeat (SSR) analysis, and sequencing of red coleoptile (Rc) and glycosyltransferase (GT) genes, followed by in silico analysis. Total anthocyanin was investigated by ultra-high performance liquid chromatography- diode array detector (UHPLC-DAD). The proteomic profiles were determined by liquid-chromatography and mass spectrometry of tryptic peptides. The SSR profiles showed a specific band in each black rice variant. The Rc gene exon-2 sequences were similar in the three black rice cultivars. The GT gene sequence was identified as a new variant that correlates with the purple stem, leaf, bran, and whole grain morphology seen exclusively in the BRWJ cultivar. The anthocyanin composition in Java black rice is diverse. The highest cyanidin level was seen in BRWJ and the highest level of peonidin-3-O-glucoside in BREJ. Proteomic profiling of the black rice cultivars demonstrated that the expression of proteins that might be related to the levels of anthocyanin synthesis varied. These studies conclude that the genomic, proteomic and anthocyanins composition of Java black rice cultivars may be used the improvement of their functional nutrition values.