Characterization Of Anthocyanins Research Articles

Extraction and characterization of anthocyanin pigments from Iris flowers and metal complex formation

Exploring the chemical processes and factors influencing the stability of the blue color derived from anthocyanins is a crucial objective in agricultural and food chemistry research. The ability of these compounds to bind with metals could potentially stabilize anthocyanins extracted from plant-based foods or enable modifying their hues for application as natural food colorants. This study had two core objectives - first, to extract and identify the major anthocyanin pigments responsible for iris flower coloration. Second, to selectively complex purified iris anthocyanins with aluminum (Al3+) and copper (Cu2+) ions, probing the coordination chemistry underlying synthetic metalloanthocyanin formation. Fresh iris flowers were collected and anthocyanins extracted using an optimized acidic solution. After separation, anthocyanins were complexed with metals Al3+ and Cu2+ at pH 5–6 to understand better the evolution of blue and green colors in anthocyanin-metal chelates. Characterization of anthocyanins and their metal complexes utilized UV–visible spectrometry, colorimetry (L\\* a\\*b\\* values), FTIR spectroscopy, and LC-MS. Metal complexation of anthocyanins exhibited bathochromic shifts of visible absorption maxima from 538 to 584 nm for Al-complex and 538–700 nm for Cu-complex. Color changes were accompanied by decreased lightness (L\\*, from 87 to 81) and color coefficients a\\* (+5.4 to −6.8) and b\\* (−12.2 to −4.8). LC-MS analysis identified five major anthocyanin aglycones: cyanidin (Cyd, m/z 289), delphinidin (Dpd, m/z 305), petunidin (Ptd, m/z 229), malvidin (Mv, m/z 329) and pelargonidin (m/z 273), along with various glycosylated derivatives. This work successfully isolated key iris anthocyanin pigments and elucidated their metal chelation interactions underlying expanded floral color production, bridging knowledge gaps about this underexplored genus.

Combinatorial preparation and structural characterization of anthocyanins and aglycones from Purple-heart Radish for evaluation of physicochemical stability and pancreatic lipase inhibitory activity

In this study, an efficient approach to preparation of different anthocyanins from Purple-heart Radish was developed by combining microwave-assisted extraction (MAE), macroporous resin purification (MRP) and ultrasound-assisted acid hydrolysis (UAAH) for evaluation of physicochemical stability and pancreatic lipase (PL) inhibitory activity. By optimization of MAE, MRP and UAAH processes, the anthocyanins reached the yield of 6.081 ± 0.106 mg/g, the purity of 78.54 ± 0.62 % (w/w) and the content of 76.29 ± 1.31 % (w/w), respectively. With high-resolution UHPLC-Q-Orbitrap/MS, 15 anthocyanins were identified as pelargonins with diverse glucosides and confirmed by pelargonidin standard. By glycosylation, pelargonins exhibited higher stability in different pH, temperature, light, metal ions environments than that of pelargonidin. However, PL inhibitory assay, kinetic analysis and molecular docking demonstrated that pelargonidin had higher PL inhibitory activity than pelargonins even though with similar binding sites and a dose–effect relationship. The above results revealed that the effect of glycosylation and deglycosylation on PL inhibitory activity and physicochemical stability.

Preparation and Characterization of Anthocyanin Loaded Lotus Pollen Exine Nanocapsules for its Use in Oral Drug Delivery Applications

Preparation and Characterization of Anthocyanin Loaded Lotus Pollen Exine Nanocapsules for its Use in Oral Drug Delivery Applications

Characterization of anthocyanins in Gynura bicolor DC using HPLC-Q-Orbitrap MS and its stability during microwave vacuum drying

Gynura bicolor DC (G. bicolor) is largely consumed as a vegetable in many parts of the world, and due to its content in anthocyanin can be considered as a health-promoting food. This study aimed to characterize the anthocyanin composition of G. bicolor and compare the effect of microwave vacuum drying (MVD) on the anthocyanin content with that of hot air drying (HAD). Anthocyanins were characterized using high-performance liquid chromatography-quadrupole-Orbitrap mass spectrometry (HPLC-Q-Orbitrap MS), which accurately identified five anthocyanin compounds. Delphinidin 3-O-neohesperidoside is the main anthocyanin compound found in G. bicolor. MVD decreased the drying time by 89% compared to HAD. MVD retained 87% of the total anthocyanins in G. bicolor, compared to 18% retained by HAD. This study revealed that MVD produced high-quality dried G. bicolor products, while exhibiting reduced processing times compared to those achieved using HAD.

Acerola (Malpighia emarginata) pulp: characterization and stability of anthocyanins under different conditions

Tropical fruits provide a high economic potential and their inclusion in the diet can provide health benefits. In this sense, this study aimed to evaluate the proximal composition, bioactive compounds, antioxidant activity, and stability of anthocyanins of acerola pulp in the absence and presence of light at temperatures of 7 and 21.7°C. The results for the proximal composition (g/100 g) were 93.49 moisture, 0.04 protein, 0.09 lipid, 0.60 ash, and 6.28 carbohydrates, totaling a 28.29 kcal/100 g caloric value. For total bioactive compounds, the results were 3.22 µg/g chlorophyll, 29.71 µg/g carotenoids, 3.74 g/100 g flavonoids, and 6.12 mg/100 g phenolic compounds. Acerola pulp showed high antioxidant activity by DPPH and ABTS methods with values of 6.17 μmol/g and 3.19 mM TEAC/g, respectively. Regarding the stability of anthocyanins, in acerola pulp stored away from light and at a temperature of 7°C, these pigments remained more stable than when subjected to light and a temperature of 21°C. Thus, it was possible to perceive that, in addition to the acerola being important for the food industry, storage under low temperatures and the absence of light can contribute to greater stability of anthocyanin pigments.

Utilizing response surface methodology to optimize the extraction and characterization of anthocyanins from Solanum melongena L. fruit

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.

Optimization, fabrication, and characterization of anthocyanin and carotenoid derivatives based dye-sensitized solar cells

The bracts of Poinsettia, Tamarillo fruit, Annatto seeds, and Pungent Chillies have been used to extract the dyes using ethanol and deionized water. A cocktail of the dyes has been made with equal concentration and will be used as a sensitizer in the proposed dye-sensitized solar cell. The individual and cocktail of the dyes are subjected to FTIR, UV–Visible spectroscopy for the identification of functional groups, and absorption wavelength to find the effectiveness of the dyes for absorption of energy of the photons. From the study, it is found that the sensitizers in the dyes have shown stronger electronic coupling and rapid electron transfer into the conduction band of the TiO2 semiconductor on the FTO substrate. J-V analysis represents photovoltaic characterization of assembled thin film nano-crystalline solar cells. Anthocyanin derivative of Poinsettia bracts attained a photo-sensitized conversion efficiency of 1.74% achieving an overlong lifespan of electrons. Ethanol was chosen for attaining the best energy conversion efficiency owing to its polarity. The presence of phytoconstituents has an impact on the color of the sensitizers and the degradation in the power conversion efficiencies was also monitored. This research examines the parameters that influence the stability of anthocyanin and carotenoid pigments, as well as the solvents required for effective derivative extraction.

Enhancement of extraction effectiveness and stability of anthocyanin from Hibiscus sabdariffa L.

Anthocyanin, a main bioactive compound found in Hibiscus sabdariffa L. extract, has attracted different fields such as food additives and functional foodstuffs due to its wide range of possible applications. However, commercial applications of anthocyanins as colourants and pharmaceuticals have been limited due to their defective extraction yield and poor stability. This study aimed to improve the extraction efficiency and enhance the stability of anthocyanin extracted from H. subdariffa L. The method of enzyme-microwave assisted extraction (EMAE, 15.37 ± 0.41 mg/g anthocyanin based on raw material) resulted in enhancing the anthocyanin recovery efficiency up to 15.35%, 23.68% and 28.04% compared to each technique of microwave-assisted extraction (MAE, 13.01 ± 0.22 mg/g), ultrasound-assisted extraction (UAE, 11.73 ± 0.28 mg/g) and enzyme-assisted extraction (EAE, 11.06 ± 0.33 mg/g). The FT-IR and UV–Vis spectra showed the identified characterization of anthocyanin. For stabilization, the colour deviation values of anthocyanin extract in cases of individuals adding catechin 1.5%, chitosan 2%, or chondroitin sulfate 3% were 9.22, 6.53, and 7.59, respectively, while the combination of the three co-pigments gave the lowest color deviation of 4.11 after 30 h investigation. This combined method prolonged the shelf-life of anthocyanin powder to 16.2 months and maintained its antioxidant activity by about 50%. In the trend of exploitation and application of bioactive components, this study would offer a promising approach to improve the extraction efficiency and the stability of anthocyanin from H. sabdariffa L. as well as valuable information for large-scale anthocyanin process and storage. • Extraction and stabilization conditions of Hibiscus sabdariffa L. anthocyanin were studied. • The method of enzyme-microwave-assisted extraction (EMAE) was the most effective. • Anthocyanin extraction yield of EMAE was 15.37 mg/g. • Catechin, chitosan and chondroitin sulfate were studied as co-pigments of anthocyanin. • The three co-pigments combination extended the shelf-life of anthocyanin powder by 6 months.

Characterisation and storage stability of aronia anthocyanins encapsulated with combinations of maltodextrin with carboxymethyl cellulose, gum Arabic, and xanthan gum

Encapsulation was used to protect anthocyanins extracted from aronia (Aronia melanocarpa) fruit using the combinations of maltodextrin (MD) with anionic polysaccharides, including carboxymethyl cellulose (CMC), gum Arabic (GA), and xanthan gum (XG) as the coating agents. The encapsulation efficiencies were 98 % in MD, MD + CMC, and MD + GA and 94 % in MD + XG. In comparison, the loading efficiency, total anthocyanins, total phenolics, and antioxidant activity were higher in the combined coating agents than in MD alone. In storage for 100 days at 25℃, the retention of anthocyanins was much higher in encapsulated aronia (88–91 %) compared with nonencapsulated aronia (47 %). Cyanidin 3-galactoside and arabinoside showed higher stability (91–93 %) than cyanidin 3-glucoside and xyloside (60–65 %). New compounds, including cyanidin 3-(coumaroyl)-pentoside and 10-carboxy-pyranocyanidin-3-hexoside, were found after 20 days, indicating that anthocyanins formed new adducts with other components in aronia. The results show that MD + CMC and MD + XG are suitable coating agents for the encapsulation of anthocyanins in aronia.

Characterization of Anthocyanins and Their Antioxidant Activities in Indian Rose Varieties (Rosa × hybrida) Using HPLC.

The present study was designed to explore the anthocyanin profile and antioxidant activities in Indian rose varieties (Rosa × hybrida). Among fifty varieties, Ashwini recorded the highest total phenolic content (427.59 ± 3.47 mg GAE/100 g) along with the highest FRAP (397.15 ± 0.82 µmol trolox/g) and DPPH free radical scavenging activity (93.47 ± 0.19%) on a fresh weight basis. A significant positive correlation was observed between total anthocyanin content, total phenolic content, and antioxidant activities. Four distinct clusters were formed according to total anthocyanins, total phenols, and antioxidant activities; white- and yellow-colored varieties were most distant from red ones. Principal component analysis revealed that variable total anthocyanin content contributed to the maximum variation among the fifty rose varieties studied. Highly anthocyanin-rich rose varieties were characterized by high-performance liquid chromatography coupled with a photodiode array detector (HPLC-PAD), which identified two major components of anthocyanins, i.e., cyanidin 3,5-di-O-glucoside and pelargonidin 3,5-di-O-glucoside. Cyanidin 3,5-di-O-glucoside was the predominant anthocyanin in red- and pink-colored varieties, whereas pelargonidin 3,5-di-O-glucoside was the major one in the orange variety. The maximum cyanidin 3,5-di-O-glucoside content was recorded in variety Ashwini (497.79 mg/100 g), whereas the maximum pelargonidin 3,5-di-O-glucoside content was recorded in Suryakiran (185.43 mg/100 g). It is suggested that the rose varieties with high anthocyanin content and antioxidant activity can be exploited as a potential source of nutraceuticals in the food industry.

Identification and characterization of anthocyanins and non-anthocyanin phenolics from Australian native fruits and their antioxidant, antidiabetic, and anti-Alzheimer potential

Polyphenols are vital bioactive constituents that have beneficial effects on human health. The aim of this study was to characterize the biologically active phenolic metabolites in Australian native commercial fruits (Kakadu plum, Davidson’s plum, quandong peach, and muntries) and their antioxidant, α-glucosidase, and acetylcholinesterase inhibition activities. Polyphenols were measured through total phenolic content (TPC), total flavonoid content (TFC), total condensed tannin (TCT), and total monomeric anthocyanin content (TMAC). Moreover, different in-vitro biological assays (DPPH, ABTS, FICA, OH-RSA, α-glucosidase, and acetylcholinesterase inhibition activities) were conducted to measure the antioxidant, anti-diabetic, and anti-Alzheimer’s potential of these selected fruits. LC-ESI-QTOF-MS/MS was implied for identification and quantification purposes. In this study, a total of 307 bioactive metabolites (51 phenolic acids, 194 flavonoids, 15 tannins, 23 other polyphenols, 5 stilbenes, 12 lignans, and 7 terpenoids) were putatively identified. A total of 41 phenolic compounds were quantified/semi-quantified. Kakadu plum was identified with a higher concentration of polyphenols and biological activities compared to Davidson plum, quandong peach, and muntries. Molecular docking was also conducted to discover the actual role of the most abundant phenolic metabolites in the α-glucosidase and acetylcholinesterase inhibition activities.

Characterization of anthocyanin and nonanthocyanidin phenolic compounds and/or their biosynthesis pathway in red-fleshed ‘Kanghong’ grape berries and their wine

This study determined the composition and content of anthocyanin compounds in red-fleshed ‘Kanghong’ (KH) berries and wine and revealed the anthocyanin biosynthesis pathway in KH flesh. The 41 anthocyanin compounds detected primarily accumulated in KH skin, followed by flesh and seeds. Anthocyanin compounds with a single glucoside, particularly malvidin-3-O-glucoside, were the most abundant components in KH berries. The percentage of anthocyanin compounds was altered in KH flesh compared to KH skin. KH berries and their wine contained a much higher anthocyanin content than Cabernet Sauvignon (CS) wine. Additionally, a total of 48 differentially accumulated nonanthocyanin phenolic compounds and 2104 differentially expressed genes between KH and CS flesh were identified, and their association analysis indicated that the metabolic flux of phenolic compounds in the phenylpropanoid pathway was promoted in KH flesh. Therefore, this work elucidated the accumulation characteristics of anthocyanins in KH berries and provided the mechanism underlying grape flesh coloration.

Compound hydrogels derived from gelatin and gellan gum regulates the release of anthocyanins in simulated digestion

Anthocyanins need be absorbed in the small intestine for prevention and therapy of intestinal diseases. However, they are usually degraded in the stomach during digestion process. Therefore, it is necessary to protect anthocyanins from degradation and maximize the release of anthocyanins in the small intestine. In this study, we encapsulated anthocyanins with Gelatin/Gellan gum in five proportions (Gelatin/Gellan gum: 10/0, 9/1, 8/2, 7/3, 6/4, w/w). The results of embedding efficiency, morphology and gel strength of the Gelatin/Gellan gum-Anthocyanins (Gel/Gen-Ans) system showed that Gelatin/Gellan gum = 8/2 (H 2) had the most compact and stable structure, as proved by the distribution analysis and structural characterization of anthocyanins. In vitro simulated digestion experiments demonstrated that anthocyanins were mainly retained inside Gel/Gen-Ans in the stomach, and subsequently released in the intestine. Moreover, biocompatibility results showed that compound hydrogels did not inhibit the proliferation of normal rat intestinal epithelial cells (IEC-6), which indicated the safety of this compound hydrogels. Taken together, this system was an effective and safe method to ensure the target release of anthocyanins.

Identification of Five Acylated Anthocyanins and Determination of Antioxidant Contents of Total Extracts of a Purple-Fleshed Ipomoea batatas L. Variety Grown in Burkina Faso

Anthocyanins are bioactive compounds, which thanks to their anti-free radical properties, can protect the human body against oxidative stress. The latter can cause many diseases, such as cancer, aging. The extract of the green cap purple variety of the sweet potato (Ipomoea batatas L.) is active against the radical ABTS. Its antioxidant content is estimated at 0.183 mg E TEAC/ g fresh material. The characterization of anthocyanins was performed by high performance liquid chromatography-mass spectrometry-UV (HPLC-MS-UV) and high performance liquid chromatography-mass spectrometry (HPLC-MS/MS) analyses. These analyses allowed the identification of five anthocyanic compounds. These are: cyanidin 3-(6''-caffeoyl- 6'''-p-hydroxybenzoyl sophoroside) -5-glucoside; cyanidin 3-(6''-feruloyl 6'''-caffeoyl sophoroside) -5-glucoside; peonidin 3-(6'''-caffeoyl sophoroside)-5-glucoside; peonidin 3-(6''-caffeoyl-6'''-p-hydroxybenzoyl sophoroside) -5-glucoside; and peonidin 3-(6''-feruloyl -6'''-caffeoyl sophoroside)-5-glucoside.

Comparative Transcriptome Analysis of the Accumulation of Anthocyanins Revealed the Underlying Metabolic and Molecular Mechanisms of Purple Pod Coloration in Okra (Abelmoschus esculentus L.).

Color is an essential agronomic trait and the consumption of high anthocyanin containing vegetables in daily diet does provide benefits to human health, but the mechanisms on anthocyanin accumulation in tender pods of okra (Abelmoschus esculentus L.) were totally unknown. In this study, a wide characterization and quantitation of anthocyanins and flavonols in tender pods of 15 okra varieties were performed by UHPLC-Q-Orbitrap HRMS for the first time. Two major anthocyanins (delphinidin 3-O-sambubioside and cyanidin 3-O-sambubioside) and six kinds of flavonol glycosides (most are quercetin-based) were identified and quantified. The coloration of the purple okra pod mainly arises from the accumulation of both delphinidin 3-O-sambubioside and cyanidin 3-O-sambubioside in most of purple varieties (Hong Yu, Bowling Red and Burgundy), except Jing Orange. The significant differences in the compositions and contents of anthocyanins are responsible for the pod color ranging from brick-red to purplish-red among the various okra cultivars. Furthermore, four representative okra cultivars exhibiting obvious differences in anthocyanin accumulation were further analyzed with transcriptome and more than 4000 conserved differentially expressed genes were identified across the three compared groups (B vs. BR, B vs. HY and B vs. JO). Based on the comprehensive analysis of transcriptomic data, it was indicated that MBW complex consisting of AeMYB114, AeTT8, and AeTTG1 and other transcriptional factors coordinately regulate the accumulation of anthocyanins via the transcriptional regulation of structural genes. Moreover, four independent working models explaining the diversities of anthocyanin pigmentation in okra pods were also proposed. Altogether, these results improved our understanding on anthocyanin accumulation in okra pods, and provided strong supports for the development of okra pod as a functional food in the future.

Characterization of anthocyanin from red sorghum (Sorghum bicolor) bran by liquid chromatography-electron spray ionization mass spectrometry analysis.

In the present study, anthocyanin pigments from red sorghum (Sorghum bicolor) bran were identified and characterized by Liquid Chromatography-Electron Spray Ionization Mass Spectrometry. The individual anthocyanins were identified by comparing their mass spectrometric data and retention times, published data. 3-deoxyanthocyanidins and methyl 3-deoxyanthocyanidins were identified in red sorghum bran. This paper presents complete LCMS profile and MS spectrometric data of red sorghum bran.

Characterization of Anthocyanins From Intraspecific Crosses of Monastrell With Other Premium Varieties.

One way in which the wine sector is reacting to the challenge of climate change is to develop plant material that is adapted to the new conditions. Such a strategy will allow the continuation of quality viticulture in traditional winemaking areas that will otherwise be abandoned. The objective of this study was to characterize the anthocyanin composition and content of selected intraspecific hybrids of Monastrell with two other varieties (Syrah and Cabernet Sauvignon). The experiment was carried out over three successive seasons, and the polyphenolic quality of the grapes and wines was assessed along with the adaptation of the hybrids to the high temperatures which will inevitably affect our area (south-eastern Spain). The results showed that, compared with grapes of the Monastrell variety and the wines made from them, most of the hybrids (MS10, MS34, and MC111) had a higher total anthocyanin concentration and overall content of acylated anthocyanins, depending on the year studied.

Characterization, antioxidant, and neuroprotective effects of anthocyanins from Nitraria tangutorum Bobr. fruit

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.

Characterization of Anthocyanins and Anthocyanin-Derivatives in Red Wines during Ageing in Custom Oxygenation Oak Wood Barrels.

The ageing of wines in oak barrels is a key stage in the production of high-quality red wines, with the type of oak chosen and the amount of oxygen received by the wine being the determining factors of the process. This work analyses the effect of ageing the same red wine in barrels with different oxygenation rates for one year (OTR), specifically the effect on the evolution of anthocyanins, their derivatives and the appearance of new pigments according to the oxygen dosage in barrels. Results show that wines aged in High-Wood-OTR barrels have a large quantity of monomeric anthocyanins and wine aged in Low-Wood-OTR barrels presents a major intensity of colour. Moreover, using LC-MS analysis, it was possible to detect and identify different families of anthocyanin derivatives, including the tentative identification of two new aldehyde-flavanol-methylpyranoanthocyanin pigments.

Simultaneous separation and preliminary purification of anthocyanins from Rosa pimpinellifolia L. fruits by microwave assisted aqueous two-phase extraction

Rosa pimpinellifolia L. fruits (RPF) have great industrial potential due to the high presence of anthocyanins. In this work, microwave-assisted aqueous two-phase extraction (MA-ATPE) was applied to simultaneous extraction and purification of anthocyanins from RPF with ethanol/ammonium sulfate aqueous two-phase system (ATPS). MA-ATPE process was optimized by single-factor experiments and response surface methodology. The optimal anthocyanin yields were achieved in conditions of 0% HCl (w:w), 26.85% ethanol (w:w), 19.15% ammonium sulfate (w:w), liquid to solid ratio 40, 17.29 min, 60 °C and 400 W. Predicted anthocyanin yield of MA-ATPE at optimum conditions were determined as 1373.04 mg cyanidin 3-glucoside equivalent/g dry RPF. The purity of anthocyanin rich extract obtained by MA-ATPE was 1.65-fold greater than microwave assisted extraction using 80% ethanol (MAE). The compositional characterization of anthocyanins were carried out with HPLC-QTOF-MS. MA-ATPE had no obvious changes on anthocyanin composition when compared to MAE. Results indicated that the MA-ATPE could be a promising method for the extraction and preliminary purification of anthocyanins from different plant materials.