Source Of Natural Pigments Research Articles

Optimization of Anthocyanin extraction from black hollyhock flower: Process efficiency, stability, and cytotoxicity assessment

Black hollyhock (Alcea rosea var. nigra) flower (BHF) serves as a plentiful natural pigment source. However, limited research has been conducted on the extraction and characterization of the anthocyanins present in BHF. This work aims to develop an environmentally friendly extraction method for efficiently obtaining natural pigments from BHF. Utilizing response surface methodology (RSM), the extraction variables were adjusted to optimize the overall anthocyanin content. The optimized conditions, entailing extraction lasting 7 min at 65°C, employing acidified water at a solvent: feed (S:F) ratio of 100:1 (v/w), resulted in extraction yield of 53 ± 2.5 % and the total anthocyanin content (TAC) of 65.7 ± 0.5 mg/ gdry weight based on cyanidin-3-O-glucoside equivalents (CGE). Furthermore, the extraction from pomace, which represents the residue subsequent to the initial extraction, exhibited 11 and 2 mg CGE/g dry weight after second and third steps of extraction, respectively. Characterization of the obtained extracts was conducted through HPLC-DAD MS analysis, and six anthocyanins were identified. The kinetic data associated with degradation of anthocyanins was well fitted with a zero-order model, which showed a half-life (t1/2) of approximately 200 days. Additionally, BHF extract exhibited no significant cytotoxicity against human dermal fibroblast cells as MTT assay indicated. This investigation introduces a potent source for anthocyanin which can be comparable to other sources and their extraction conditions in terms of stability, TAC, and extraction yield.

Microbial Pigment Isolation, Culturing, and Extraction to Use as Textile Dyes

The textile industry is one of the largest worldwide polluters of clean water due to the heavy use of synthetic dyes. These chemicals negatively affect the environment, especially aquatic life due to their toxic and mutagenic properties. Synthetic dyes cause harm to human health such as skin allergies and respiratory sensitization. Several advantages such as ease of extraction, availability, high yields and no seasonal variation make microbial pigments the most ideal source of natural pigments. This study was done to isolate colour pigment producing bacteria and fungi from soil collected from organic farms from various locations in Sri Lanka. Out of 7 soil samples, 3 yielded pigment producing bacteria and fungi. In total, 9 pigment producing bacteria and 3 pigment producing fungi were isolated. Gause’s synthetic agar yielded the most pigmented isolates. Isolates were inoculated in broths and pigment production was observed. Extracellular pigments produced by 5 of the bacterial isolates were extracted by a water-based method. The antibacterial activity of the pigments in their crude and concentrated forms was tested using the well diffusion method against Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 6538P. Inhibition zone against S. aureus was observed for both crude (12.33±0.58mm) and concentrated pigments (9.67±0.58mm) extracted from purple pigment producing bacterial isolate (BPU). This pigment has the potential to be used in antibacterial textile preparation. Extracted pigments were used to dye scoured cotton fabric with the use of 3% alum as mordant. Pigment from BPU isolate resulted in better coloured fabric.

Laser-induced fluorescence spectroscopic investigation of Echium amoenum decoction

Herbs containing medicinal ingredients with nutritional value have recently gained attention as an alternative to synthetic drugs. Aside from their pharmaceutical worthiness, a variety of naturally occurring chromophores with specific optical properties have made them valuable sources of natural pigments for many biophotonic applications. Echium Amoenum (EA) is one of the colorful flowers that has been used in traditional medicine for a long time. To our knowledge, although several studies have been carried out on the characterization of EA ingredients and their chemical activities, information on EA fluorescence is still lacking. Here, laser induced fluorescence (LIF) features of the decoction of EA petals were evaluated and found to be highly dependent on the excitation wavelength, EA concentration, and detection geometry. The abundance of pigments, the boundaries of their absorption/emission spectral regions, and the corresponding energy transfer ascertain the contribution of certain chromophores to the cumulative fluorescence activity. Upon deconvolution of the LIF spectra, it was revealed that the different emission bands of rosmarinic acid (corresponding to its dissociated forms) and the luminescent activity of luteolin and β-carotene mainly determine the quantum distribution of the fluorescence of EA. Angular measurement of LIF in a symmetric cylindrical arrangement revealed the presence of the inner filters mainly due to the reabsorption of LIF photons by anthocyanins (flavone, pelargonidin, delphinidin and cyanidin) and carotenoids. We hope that the obtained results will be useful in various fields of photochemistry and biophotonics.

Development of bio-active cotton fabric coated with betalain extract as encapsulating agent for active packaging textiles

The development of bio-active cotton fabric based on natural polymers and pigments has been a significant material for biodegradable textile packaging in recent years. Betalain extracted (BE) from Red beet root (RBR) is a rich source of natural pigments and has potential health benefits as an antioxidant and in biological activities which used as food, beverage, and drug colorant. However, BE pigments are photochromically unstable and have interest applications, thereby motivating the use of microencapsulation technology to maintain their stability and increase their shelf lifetime. Thus, in the present work Incorporating BE into gelatinized corn starch (GS) and Arabic gum (AG) for manufacturing stabilized BE microcapsules with tunable antioxidant and biological properties by freeze-drying method. The produced encapsulating agent (EA) powders were analyzed by scanning electron microscope (SEM) for particle morphology and FTIR of selected EA was carried out. Monitoring of coloring strength values (K/S) and Color parameters before and after storage as well as storage stability of these microcapsules at different pH’s was also studied. The current study was performed to design multifunctional cotton fabric, for this purpose the cotton fabric was treated with keratin to improve its affinity toward 100 % BE, with and without (BE) EA were determined using a pad dry process. The chemical properties, physical properties, mechanical properties, thermal stability, and functional properties of the coated fabrics with and without (BE) as well as color parameters were determined. The results showed that the fabric coated with 100 % BE and 30 % BE incorporating or encapsulating with 60 % GS and 10 % AG exhibited good mechanical properties, excellent thermal stability, and significant antioxidant and antimicrobial activity compared to the uncoated fabric. The antioxidant release of BTE from the fabric coated with 60/10/30 EA was controlled by diffusion. According to the results, the developed multifunctional coated fabrics with BE encapsulating agent can be considered as a good potential material for active packaging textiles for various applications.

Natural Pigments Recovery from Food By-Products: Health Benefits towards the Food Industry.

Given the health risks associated with synthetic colorants, natural pigments have emerged as a promising alternative. These renewable choices not only provide health benefits but also offer valuable technical and sensory properties to food systems. The effective application of natural colorants, however, requires the optimization of processing conditions, exploration of new sources, and development of novel formulations to ensure stability and maintain their inherent qualities. Several natural pigment sources have been explored to achieve the broad color range desired by consumers. The purpose of this review is to explore the current advances in the obtention and utilization of natural pigments derived from by-products, which possess health-enhancing properties and are extracted through environmentally friendly methods. Moreover, this review provides new insights into the extraction processes, applications, and bioactivities of different types of pigments.

Multimodal non-invasive probing of stress-induced carotenogenesis in the cells of microalga Bracteacoccus aggregatus.

Microalgae are the richest source of natural carotenoids-accessory photosynthetic pigments used as natural antioxidants, safe colorants, and nutraceuticals. Microalga Bracteacoccus aggregatus IPPAS C-2045 responds to stresses, including high light, with carotenogenesis-gross accumulation of secondary carotenoids (the carotenoids structurally and energetically uncoupled from photosynthesis). Precise mechanisms of cytoplasmic transport and subcellular distribution of the secondary carotenoids under stress are still unknown. Using multimodal imaging combining micro-Raman imaging (MRI), fluorescent lifetime (τ) imaging (FLIM), and transmission electron microscopy (TEM), we monitored ultrastructural and biochemical rearrangements of B. aggregatus cells during the stress-induced carotenogenesis. MRI revealed a decline in the diversity of molecular surrounding of the carotenoids in the cells compatible with the relocation of the bulk of the carotenoids in the cell from functionally and structurally heterogeneous photosynthetic apparatus to the more homogenous lipid matrix of the oleosomes. Two-photon FLIM highlighted the pigment transformation in the cell during the stress-induced carotenogenesis. The structures co-localized with the carotenoids with shorter τ (mainly chloroplast) shrunk, whereas the structures harboring secondary carotenoids with longer τ (mainly oleosomes) expanded. These changes were in line with the ultrastructural data (TEM). Fluorescence of B. aggregatus carotenoids, either in situ or in acetone extracts, possessed a surprisingly long lifetime. We hypothesize that the extension of τ of the carotenoids is due to their aggregation and/or association with lipids and proteins. The propagation of the carotenoids with prolonged τ is considered to be a manifestation of the secondary carotenogenesis suitable for its non-invasive monitoring with multimodal imaging.

Bio-pigment extraction from blue-color flowering landscape ornamentals

The plants used in landscaping, which typically grow in the wild, along roads, or on homestead land, produce flowers in different shades of colors, from which pigments in other hues can be derived. In this study, six aqueous extraction techniques were used to extract pigments from three plant species, Lagerstroemia sp., Clitoria sp., and Eichhorniacrassipesthat, which produce blue-colored flowers. This study aimed to standardize the processes for extracting pigments from flowers of naturally occurring plant species, identify potential sources of blue-colored natural pigments and assess the durability and quality of the pigments. Clitoria sp. had the highest anthocyanin concentration (64.44 mg/l) when extracted with microwave assistance.

Optimization of Bioactive Compound Extraction from Saffron Petals Using Ultrasound-Assisted Acidified Ethanol Solvent: Adding Value to Food Waste.

The saffron industry produces large by-products, including petals with potential bioactive compounds, which are cheap and abundant, making them an attractive alternative to expensive stigmas for extracting bioactive components. This study aimed to optimize the extraction conditions of bioactive compounds from vacuum-dried saffron petals using an ultrasound-assisted acidified ethanol solvent. Three factors were considered: ethanol concentration (0-96%), citric acid concentration in the final solvent (0-1%), and ultrasound power (0-400 watt). This study examined the effects of these factors on parameters like maximum antioxidant activity, total anthocyanin content, total phenolic content, and the total flavonoid content of the extraction. This study found that saffron petal extract's antioxidant activity increases with higher ethanol concentration, citric acid dose, and ultrasound power, but that an increased water content leads to non-antioxidant compounds. Increasing the dosage of citric acid improved the extraction of cyanidin-3-glucoside at different ultrasound power levels. The highest extraction was achieved with 400 watts of ultrasound power and 1% citric acid. Ethanol concentration did not affect anthocyanin extraction. Higher ethanol concentration and greater citric acid concentration doses resulted in the maximum extraction of total phenolic content, with a noticeable drop in extraction at higher purity levels. This study found that increasing the proportion of citric acid in the final solvent did not affect flavonoid extraction at high ethanol concentration levels, and the highest efficiency was observed at 200 watts of ultrasound power. The optimum values of the independent parameters for extracting bioactive compounds from saffron petals included 96% ethanol concentration, 0.67% citric acid concentration, and 216 watts of ultrasound power, resulting in a desirability value of 0.82. This ultrasound-assisted acidified ethanolic extract can be used in the food industry as a natural antioxidant and pigment source.

PENGUNAAN EKSTRAK TOMAT SEBAGAI INOVASI PAKAN ALAMI UNTUK MENINGKATKAN KUALITAS WARNA IKAN BADUT MERAH MARUN (Amphiprion biaculeatus, Bloch 1790)

Background: Amphiprion biaculeatus, Bloch 1790 is one of the exported marine ornamental fish commodities. To meet export demand, must be from cultivation fish. However, the problem faced in cultivation conditions is that the color of the fish is not as attractive as in nature. This is due to uniform feeding. Therefore, alternative solutions are needed to enrich feed with natural pigment sources. One of them is red ripe tomato extract with high carotene content. Methods: The study used a completely randomized design with extract concentration treatments (0, 25%, 50%, 75%). Natural feed is made by coating, then applied to non-breeder sized fish obtained from BPBL Ambon. Extract efficiency parameters were measured through color characteristics, carotene content in the skin and fins, total length and body weight. The data obtained were analyzed using ANOVA and continued with the DMRT test at a significance level of 95%. Results: The results showed that tomato extract had a significant effect on color characteristics, carotenoid content, total length and body weight in maroon clownfish. The concentration of tomato extract which had the highest value for all parameters measured was in treatment 75% : 75 mL tomato extract + 10 mL binder + 15 g commercial feed). Conclusion: Tomato extract has the potential as a natural feed that can improve the color quality of A. biaculeatus with a usable concentration of 75%.

Evaluation of Verbascum flower extracts as a natural source of pigments with potential health benefits.

Crocins are bioactive glucosylated apocarotenoids that confer a yellow pigmentation. In addition to their coloring ability, crocins offer potential health benefits because of their antioxidant and anti-inflammatory properties. These compounds are present in the flowers and fruits of a few plant species, including saffron, gardenia, Buddleja and Verbascum species. Saffron extracts have been used for the formulation of functional foods. However, there is no evidence of the use of the other plants producing crocins in the food industry. This study evaluated the effect of the addition of ground dry flowers of two Verbascum species, with antioxidant activity, as well as dry fruit powder, from a recently engineered tomato plant producing fruits that accumulate high levels of crocins, as functional ingredients during the processing of rice, wheat cous-cous and maize noodles, providing a yellow pigmentation. Correlation analyses revealed that the increased antioxidant activity in the three food matrices was due to the presence of crocins, which showed no toxicity. Furthermore, in vitro digestion showed that crocins were more bioaccessible from rice than from cous-cous or maize noodles, inferring the importance of the food matrix in bio accessibility. The obtained results showed the commercial potential of Verbascum's flowers, as a source of crocins, natural pigments with antioxidant activities.

Antioxidant and Antibacterial Properties of bio-pigment from Beta vulgaris

ABSTRACT: Plants are essential for sustaining life on our planet, providing a diverse range of species that possess therapeutic properties. With a growing awareness of health and well-being among consumers, there has been a rise in the popularity of natural colorants sourced from plant-based materials. In this context, the main objective of this research was to extract valuable natural pigments from Beta vulgaris (commonly known as beetroot), with the aim of increasing the availability of pigments from natural sources while simultaneously minimizing environmental and health risks. The crude extract of pigments was obtained using the maceration method during the extraction process. The crude extract was then purified using flash column chromatography with various solvents as the mobile phase. Preliminary phytochemical screening revealed the presence of active compounds like phenols, carbohydrates, glycosides, phytosterols, tannins, flavonoids, alkaloids, terpenoids, and saponins. High-Performance Thin-Layer Chromatography (HPTLC) was performed to analyze the betalain profile, showing distinct bands at specific Rf values. The specific functional groups were identified in the Fourier-Transform Infrared (FTIR) spectrum based on the presence of characteristic bands. Antibacterial activity testing demonstrated varying degrees of inhibition against test organisms like Bacillus cereus, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The evaluated plant pigments exhibited positive results in terms of antioxidant activity, exhibiting free radical scavenging capabilities. The aqueous methanol extract showed the highest extraction yield at 36.71%. The aqueous methanol extract of Beta vulgaris showed the maximum antibacterial activity at 20 mm against Bacillus cereus. The methanol extract and aqueous ethanol extract displayed the lowest IC50 values (45.56 µg/ml and 43.23 µg/ml, respectively), indicating their high antioxidant potential. These findings highlight the promising potential of Beta vulgaris as a valuable source of natural pigments with both antibacterial and antioxidant properties.

Stability and shelf life modeling of natural colorant from bee pollen

One of the main limitations for natural food colorants as potential replacements for synthetic alternatives is their stability and shelf life, which are determinant to their successful marketing. Bee pollen can be used as a source of natural pigments to substitute artificial colorants in the food, medicine, and cosmetics industries, showing advantages due to their bioactivity. This work studied the stability and shelf life of an oil-based carotenoid-rich extract (CRE) obtained from bee pollen via microwave-assisted extraction. Total carotenoid content (TCC), lipid oxidation indices, and color in the CIELAB space were evaluated during 90 days at three different temperatures: 30 °C, 45 °C, and 60 °C. The results showed that while the color remains stable, the TCC decreases and the peroxide index increases as a function of temperature. The overall CRE degradation kinetics was better modeled as a zero-order reaction and, with the Arrhenius equation, the shelf life of the colorant was determined as 37 months (at 20 °C) with a hue (hab) critical value of 70. These results demonstrate the high stability of a new type of natural colorant as well as the efficacy of bee pollen carotenoids in combination with oil lipids in color preservation.

Theoretical and Experimental Studies on the Evidence of 1,3-β-Glucan in Marennine of Haslea ostrearia.

Marennine, a blue pigment produced by the blue diatom Haslea ostrearia, is known to have some biological activities. This pigment is responsible for the greening of oysters on the West Coast of France. Other new species of blue diatom, H. karadagensis, H. silbo sp. inedit., H. provincialis sp. inedit, and H. nusantara, also produce marennine-like pigments with similar biological activities. Aside from being a potential source of natural blue pigments, H. ostrearia-like diatoms present a commercial potential for the aquaculture, food, cosmetics, and health industries. Unfortunately, for a hundred years, the exact molecular structure of this bioactive compound has remained a mystery. A lot of hypotheses regarding the chemical structure of marennine have been proposed. The recent discovery of this structure revealed that it is a macromolecule, mainly carbohydrates, with a complex composition. In this study, some glycoside hydrolases were used to digest marennine, and the products were further analyzed using nuclear magnetic resonance (NMR) and mass spectroscopy (MS). The reducing sugar assay showed that marennine was hydrolyzed only by endo-1,3-β-glucanase. Further insight into the structure of marennine was provided by the spectrum of 1H NMR, MS, a colorimetric assay, and a computational study, which suggest that the chemical structure of marennine contains 1,3-β-glucan.

Geolashon (Teloschistes flavicans), a natural yellow dye from the Peruvian Andes: traditional uses, bioactive extraction, and potential applications

Recently, interest in studying pigments from lichens has been aroused due to their bioactive properties and health benefits. The Geolashon (Teloschistes flavicans) is a thousand-year-old lichen from the Peruvian Andes characterized by its yellow filaments, traditionally used by the Peruvian inhabitants as a natural pigment for making handicrafts and medicinal purposes. In this sense, this article aims to compile all the studies on Geolashon as a source of natural yellow pigments, starting from its importance and applications by the Andean population to research on obtaining, characterizing, and properties of its extracts. Although studies on this lichen are limited, it was observed that the obtained from lichen are rich in 3-[1’-(2”,3”-dihydroxy-phenyl)-propyl]-7-hydroxy- chroman-4-one, vicanicin, parietin, other compounds and has antidiabetic, antibacterial, antileukemic, antimicrobial, anticancer and termiticide activity that would be interesting for use in the pharmaceutical, cosmetic, food and agricultural industries, generating added value in the final product. Aspects such as processing, functional properties, and toxicology of the bioactive components of Geolashon must be studied for its correct use.

ANTIMICROBIAL ACTIVITIES OF CURCUMIN EXTRACTED FROM SELECTED ZINGIBERACEAE SPECIES AS POTENTIAL HALAL ACTIVE PHARMACEUTICAL INGREDIENT

The ginger family (Zingiberaceae) includes plants with a distinct smell and taste that are commonly used as spices in the kitchen, but also in a variety of industries (pharmaceutical, medical, and cosmetic) due to their demonstrated biological activity. This study describes the antibacterial activity of curcumin extracts from selected species of Zingiberaceae family namely “temu emas” (Curcuma zeodoria). “temu kunci” (Curcuma manga), “temu pauh” (Curcuma amada), “lempoyang” (Zingiber zerumbit) and “cekur” (Kaempferia galangal). Extracts of these compounds were studied on Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 35218), Salmonella typhimurium (ATCC 14028), Candida albicans (ATCC 10231) and Aspergilus brasiliensis (ATCC 16404). Turbidity is taken as an indication of growth, thus the lowest concentration, which remains clear after macroscopic evaluation is taken as the minimum inhibitory concentration (MIC). In conclusion, amongst the studied members of Zingiberaceae, temu emas curcumin natural pigment extracts showed the best antibacterial activities against E. coli ATCC 35218 (2 µg / µL), S. typhimurium ATCC 14028 (2 µg / µL), C. albicans ATCC 10231 (2 µg / µL), A. brasiliensis ATCC 16404 (2 µg / µL) and S. aureus ATCC 25923 (3 µg / µL). The outcome of this research will be contributing towards new natural carotenoid pigment sources as potential active pharmaceutical ingredients which can be beneficial to halal health-promoting products industry.

Arnebia benthamii cell suspension cultures as a source of natural red pigments: optimization of shaking speed and inoculum density to maximize process productivity during sequential scaleup

Arnebia benthamii cell suspension cultures as a source of natural red pigments: optimization of shaking speed and inoculum density to maximize process productivity during sequential scaleup

Valuable pigments from microalgae: phycobiliproteins, primary carotenoids, and fucoxanthin.

Phycobiliproteins, carotenoids and fucoxanthin are photosynthetic pigments extracted from microalgae and cyanobacteria with great potential biotechnological applications, as healthy food colorants and cosmetics. Phycocyanin possesses a brilliant blue color, with fluorescent properties making it useful as a reagent for immunological essays. The most important source of phycocyanin is the cyanobacterium Arthrospira platensis, however, recently, the Rhodophyta Galdieria sulphuraria has also been identified as such. The main obstacle to the commercialization of phycocyanin is represented by its chemical instability, strongly reducing its shelf-life. Moreover, the high level of purity needed for pharmaceutical applications requires several steps which increase both the production time and cost. Microalgae (Chlorella, Dunaliella, Nannochloropsis, Scenedesmus) produce several light harvesting carotenoids, and are able to manage with oxidative stress, due to their free radical scavenging properties, which makes them suitable for use as source of natural antioxidants. Many studies focused on the selection of the most promising strains producing valuable carotenoids and on their extraction and purification. Among carotenoids produced by marine microalgae, fucoxanthin is the most abundant, representing more than 10% of total carotenoids. Despite the abundance and diversity of fucoxanthin producing microalgae only a few species have been studied for commercial production, the most relevant being Phaeodactylum tricornutum. Due to its antioxidant activity, fucoxanthin can bring various potential benefits to the prevention and treatment of lifestyle-related diseases. In this review, we update the main results achieved in the production, extraction, purification, and commercialization of these important pigments, motivating the cultivation of microalgae as a source of natural pigments.

Mechanical processing of Phaeodactylum tricornutum and Tetraselmis chui biomass affects phenolic and antioxidant compound availability, nutrient digestibility and deposition of carotenoids in Atlantic salmon

Cell walls of microalgae differ both in terms of chemical composition and architecture. Certain characteristics of cell walls limit both the effectiveness of extraction of valuable constituents and nutrient bioavailability and bioaccessibility in fish. We first investigated the potential of bead milling to disrupt cell walls to improve extractability of bioactive compounds from Phaeodactylum tricornutum and Tetraselmis chui. We also evaluated the effect of the mechanical treatment on i) digestibility of nutrients in the two microalgae and ii) fatty acid and pigment content of fillet of Atlantic salmon fed the algae diets.Cell wall disruption facilitated efficient release of total phenolic compounds (TPC), chlorophyll A, chlorophyll B and total carotenoids from both microalgae species, but increased only the total antioxidant capacity (TAC) of T. chuii. The polyphenol profile varied between the two species; we identified 2 and 6 polyphenols from P. tricornutum and T. chui, respectively.For the feeding experiment, microalgae biomass, intact or cell wall disrupted (90.7 and 76.4% disruption degree for T. chui and P. tricornutum, respectively), were mixed with the other feed ingredients. Atlantic salmon (315 g start weight / 55 fish per tank) were fed one of the five extruded experimental diets (a fishmeal-based reference diet and four feeds with 30% of the whole or broken microalgae biomass added to the reference diet). The digestibility of protein in the P. tricornutum was significantly higher compared to that of T. chui. Breaking the cell walls by bead milling caused a significant improvement in digestibility of protein in T. chui. The apparent digestibility coefficient of lipid was higher in P. tricornutum and bead milling improved the digestibility of the two algae. However, bead milling did not favourably change the fatty acid profile of Atlantic salmon. At the end of the feeding trial, P. tricornutum-fed fish had significantly improved pigmentation, probably due to the higher content of fucoxanthin and fucoxanthinol compared to the fish fed the reference diet. The main conclusion from the mechanical processing of the microalgae is that bead milling can increase i) the extractability of polyphenols and pigments, ii) the digestibility of lipid in both algae while the effect on protein was improved only for T. chui. Furthermore, P. tricornutum can be considered a natural pigment source in the feeds of Atlantic salmon.

Insights into the pigment and non-pigment phenolic profile of polyphenol extracts of jujube peel and their antioxidant and lipid-lowering activities

This study aimed to provide a comprehensive overview of the pigment and non-pigment phenolic profile of polyphenol extracts of jujube peel and their bioactivities. Firstly, the pigment and non-pigment phenolic composition as well as antioxidant activities of free and bound polyphenol extracts in jujube peel were compared among twelve varieties systematically. Then the antioxidant and lipid-lowering activities of free and bound polyphenol extracts of ‘Junzao’ jujube peel were investigated representatively. Overall, 23 phenolic compounds were identified, in which flavonols were the main pigments and all varieties showed similar qualitative patterns but different quantitative characteristics. The antioxidant activities significantly correlated with the content of total phenolics and total flavonoids. Furtherly, both free and bound polyphenol extracts of ‘Junzao’ jujube peel exhibited DPPH, ABTS free radical scavenging capacity, and oxygen radical absorbance capacity in a dose-dependent manner. Besides, both of them improved the resistance of Caenorhabditis elegans under H2O2 oxidative stress and heat stress at 37 °C (20–100 μg/mL). What's more, compared to free polyphenol extract, bound polyphenol extract decreased the level of body lipid accumulation and triglyceride more effectively. These results suggest that jujube peel is an exploitable source of natural flavonoid pigments and phenolic ingredients with strong antioxidant and lipid-lowering properties.

Insight into Green Extraction for Roselle as a Source of Natural Red Pigments: A Review.

Roselle (Hibiscus sabdariffa L.) is a source of anthocyanins as red pigments that is extensively farmed in tropical and subtropical regions, including Indonesia, Malaysia, China, Thailand, Egypt, Mexico, and West India. The roselle plant contains a variety of nutrients, including anthocyanins, organic acids, pectin, etc. Due to the toxicity and combustibility of the solvents, traditional extraction methods for these compounds are restricted. Obtaining pure extracts is typically a lengthy procedure requiring many processes. Supercritical carbon dioxide (ScCO2) extraction as a green technology is rapidly improving and extending its application domains. The advantages of this method are zero waste production, quicker extraction times, and reduced solvent consumption. The ScCO2 extraction of natural pigments has great promise in food, pharmaceuticals, cosmetics, and textiles, among other uses. The ScCO2 technique for natural pigments may also be advantageous in a variety of other contexts. Due to their minimal environmental risk, the high-quality red pigments of roselle rich in anthocyanins extracted using ScCO2 extraction have a high sustainability potential. Therefore, the objective of this review is to increase knowledge related to the natural colorant of roselle as a substitute for chemically manufactured colorants using ScCO2 as a green method. This article covers ScCO2 extraction, particularly as it relates to the optimization of pigments that promote health. This article focuses on the high extraction efficiency of ScCO2 extraction. Natural colorants extracted via ScCO2 are regarded as safe compounds, especially for human consumption, such as novel functional food additives and textile and pharmaceutical colors.