Natural Color Research Articles

Microencapsulation of mechanically extracted annatto for improved use in food products

Annatto is commonly used as a natural colourant in processed food products. Due to its chemical structure, it is sensitive to environmental factors such as oxygen, temperature and light. Carotenoid extraction using chemical methods requires greater expenditure of time and energy, leading to potential repercussions on the quality and safety of the end product. This study aims to encapsulate the Annatto extract (AE) produced using a developed extractor with different concentrations of maltodextrin (MD) and gum arabic (GA) used as carrier materials to improve the solubility and stability. The formulation 50:0 (MD: GA) showed a remarkable microencapsulation efficiency 86.28 ± 0.14 % with a process yield 195.75 ± 3.20 g/500 ml, bulk density 0.281 ± 0.012 g cm−3 and water activity of 0.65 ± 0.02. The AE microcapsules obtained good homogeneity and high solubility (>97 %) with a low moisture content of 4.07 ± 0.06 %. Furthermore, it was morphologically characterized as dodecahedron-shaped with a smooth surface and the absence of cracks or fissures offering complete protection to the bioactive compound encapsulated. The presence of bixin and polyphenol was confirmed by the FT-IR bands at 1646.91 cm−1, 1151.29 cm−1 and 926.26 cm−1. The purity was confirmed by the peaks drawn in the HPLC analysis. AE microcapsules were evaluated for heat stability up to 160 °C and storage stability for 60 days. Therefore, AE powders can be used as an alternative to synthetic additives which offer great potential as colorants in food matrixes.

Enhancing thermal consistency and stability of quantum dots through encapsulation: A study on microscale-structured hybrid for WLEDs

Quantum dots (QDs) are regarded as highly potential materials for color conversion in light-emitting diodes (LEDs) and display technologies owing to their distinctive and outstanding optical characteristics. Nevertheless, the energy transfer process occurring among various colored QDs, known as Förster resonance energy transfer (FRET), results in a notable redshift in fluorescence emission, restricting the precise control of photoluminescence spectra in fabricated devices. This study presents a dual-impact technique to enhance the stability of CdSe/ZnS colloidal QDs while also preventing the FRET process. This is achieved by encapsulating the QDs within silica (SiO2) and ethylene-vinyl acetate (EVA) films. The research features two distinct encapsulation methods: enveloping multiple QDs within a SiO2 matrix (MQD) and adsorbing QDs onto SiO2 spheres as a shell (SQD and SQDS). Those hybrid structures are successfully fabricated with their nanostructure, chemical composition, and optical properties extensively analyzed. Moreover, the photo-physical properties of QDs/SiO2/EVA hybrid composite films and their impact on blue lightemitting diodes (LEDs) and White-LEDs have been conducted. Among those formulations explored, the MQD/EVA films stand out, displaying natural sunlight color emission with a color temperature of 4214 K, a color coordinate at (0.37, 0.37), and significant improvements in chromatic and thermal stability under high driving power. The successful integration of high-molecular-weight polymers and SiO2 coatings highlights the effectiveness of this approach in producing robust, high-quality QD-polymer film composites, making them ideal candidates for display technologies.

Biosynthesis of Indigo Dyes and Their Application in Green Chemical and Visual Biosensing for Heavy Metals.

Fermentative production of natural colorants using microbial strains has emerged as a cost-effective and sustainable alternative to chemical synthesis. Visual pigments are used as signal outputs in colorimetric bacterial biosensors, a promising method for monitoring environmental pollutants. In this study, we engineered four self-sufficient indigo-forming enzymes, including HbpAv, bFMO, cFMO, and rFPMO, in a model bacterium E. coli. TrxA-bFMO was chosen for its strong ability to produce indigo under T7 lac and mer promoters' regulation. The choice of bacterial hosts, the supplementation of substrate l-tryptophan, and ventilation were crucial factors affecting indigo production. The indigo reporter validated the biosensors for Hg(II), Pb(II), As(III), and Cd(II). The biosensors reported Hg(II) as low as 14.1 nM, Pb(II) as low as 1.5 nM, and As(III) as low as 4.5 nM but increased to 25 μM for Cd(II). The detection ranges for Hg(II), Pb(II), As(III), and Cd(II) were quantified from 14.1 to 225 nM, 1.5 to 24.4 nM, 4.5 to 73.2 nM, and 25 to 200 μM, respectively. The sensitivity, responsive concentration range, and selectivity are comparable to β-galactosidase and luciferase reporter enzymes. This study suggests that engineered enzymes for indigo production have great potential for green chemical synthesis. Additionally, heterologous biosynthesis of indigo production can lead to the development of novel, low-cost, and mini-equipment bacterial biosensors with zero background noise for visual monitoring of pollutant heavy metals.

Development of functional probiotic yogurt from buffalo milk supplemented with red beetroot (Beta vulgaris L.) as an antioxidant, natural colorant, and starter growth stimulant

The physicochemical, sensorial, and probiotics viability properties of supplemented probiotic yogurt with beet juice (BJ) at various ratios (0–5)% in fresh and stored yogurts were determined. 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity (%) and minerals content of BJ-yogurts were increased. The color aspects (ΔE) were improved with the increasing of BJ. BJ-yogurts at 1 and 3 % were color-stable when stored in the refrigerator (5 ± 1 °C) for 9 days. The syneresis reached of 42.9, 43.0, 43.5, and 43.5 mL for control, 1 %, 3 %, and 5 % BJ, respectively in stored yogurts for 12 days. Moreover, the probiotic yogurt viability in BJ-yogurts treatments was found to be higher (p < 0.05) than control which recorded of 7.0 ± 0.08, 7.22±0.04, 7.34±0.002 log cfu/mL for streptococci, lactobacilli, and bifidobacteria counts respectively in 5 % BJ treatment, on the other hand, in control recorded of 6.76±0.07, 7.11±0.06, 6.66±0.030 log cfu/mL for streptococci, lactobacilli, and bifidobacteria counts respectively; indicating that BJ had a stimulating effect on the additive starter. Fresh yogurts with 1 % BJ had superior sensorial scores than other treatments, and generally maintained desirable organoleptic attributes for up to 9 days. This study provides a nutritious, low-cost, stable, and attractive colored yogurts from buffalo milk without negative impact on physiochemical qualities.

An Improved Detail-Enhancement CycleGAN Using AdaLIN for Facial Style Transfer

The rise of comics and games has led to increased artistic processing of portrait photos. With growing commercial demand and advancements in deep learning, neural networks for rapid facial style transfer have become a key research area in computer vision. This involves converting face photos into different styles while preserving content. Face images are more complex than regular images, requiring extensive modification. However, current methods often face issues such as unnatural color transitions, loss of detail in highlighted areas, and noticeable artifacts along edges, resulting in low-quality stylized images. In this study, an enhanced generative adversarial network (GAN) is proposed, which is based on Adaptive Layer Instance Normalization (AdaLIN) + Laplacian. This approach incorporates the AdaLIN normalization method, allowing for the dynamic adjustment of Instance Normalization (IN) and Layer Normalization (LN) parameters’ weights during training. By combining the strengths of both normalization techniques, the model selectively preserves and alters content information to some extent, aiming to strike a balance between style and content. This helps address problems such as unnatural color transitions and loss of details in highlights that lead to color inconsistencies. Furthermore, the introduction of a Laplacian regularization term aids in denoising the image, preventing noise features from interfering with the color transfer process. This regularization also helps reduce color artifacts along the face’s edges caused by noise while maintaining the image’s contour information. These enhancements significantly enhance the quality of the generated face images. To compare our method with traditional CycleGAN and recent algorithms such as XGAN and CariGAN, both subjective and objective evaluations were conducted. Subjectively, our method demonstrates more natural color transitions and superior artifact elimination, achieving higher scores in Mean Opinion Score (MOS) evaluations. Objectively, experiments using our method yielded better scores across three metrics: FID, SSIM, and MS-SSIM. The effectiveness of the proposed methods is validated through both objective and subjective evaluations.

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.

Generic color correction for tone mapping operators in high dynamic range imaging

One of the significant challenges in tone mapping is to preserve the perceptual quality of the tone-mapped images. Traditional tone mapping operators (TMOs) compress the luminance of high dynamic range (HDR) images with little to no consideration of image color information resulting into suboptimal colors. Existing color management algorithms require either manual parameter tuning or introducing lightness and hue shifts. The current study aimed to develop a color correction model in plausible agreement with the psychophysical phenomenon of color appearance perception for optimal color reproduction of tone mapped images. The proposed model leverages CIECAM16 perceptual correlates i.e., lightness, chroma, and hue. It is adaptive and entirely automatic while preserving the lightness of the tone-mapped image and maintaining the hue from the HDR image. Moreover, it does not require any gamut mapping correction algorithm in natural color reproduction. The effectiveness of the model was validated using objective and subjective methods. The experiments revealed that the model achieved optimal color reproduction in terms of the naturalness of the colors.

Phycocyanin Encapsulation in Carboxymethyl Chitosan and Whey Protein Isolate as a Strategy to Enhance Physicochemical Stability as a Food Coloring: A Review

Color additives, also known as food colorings, are substances added to food and beverages to enhance their visual appeal and consumer acceptance. The color of a food product serves as an indicator of attributes like flavor, safety, and nutritional value. Unlike other natural colors, blue-colored fruits and vegetables are rare, making blue associated with synthetic food coloring. Phycocyanin (PC), a natural blue pigment found in Spirulina, has garnered attention for its various biological properties, including antioxidant and anti-inflammatory activities. However, its industrial application limited by susceptibility to factors like high temperatures and pH variations during processing. Encapsulation, a technique involving the trapping of bioactive ingredients in carriers, can address these issues. In this study, chitosan derivatives, Carboxymethyl Chitosan (CMC)-Whey Protein Isolate (WPI) used as a coating for complexes in the encapsulation of phycocyanin. Encapsulation employed to improve pigment stability, and the study investigates the impact of ratios, pH, and CaCl2 concentration addition as a crosslinking agent. The selection of the appropriate CMC-WPI ratio is crucial for achieving good physicochemical properties, high encapsulation efficiency, and survivability against gastrointestinal and storage conditions. The encapsulated phycocyanin demonstrates stability across various pH values, with the concentration of CaCl2 influencing particle diameter and shape.

Application and toxicological study of polyvinyl acetate (PVAc) coating on lemon (Citrus limon L.) fruit to extend the shelf life

The objective of the present study is to examine how different concentrations of polyvinyl acetate (PVAc) coating (2.5%, 5.0%, 7.5%, 10.0%, and 12.5%) affect the quality of lemons during storage at (27 ± 2)°C, with the aim of extending their shelf life. Lemons are known for being a rich source of citric acid, ascorbic acid, and dietary fiber. During the study, the coated lemons were regularly assessed for various parameters such as weight loss, respiration rate, firmness, decay incidence, total soluble solids, pH, ascorbic acid, and juice content. The results revealed that lemons coated with 10.0% and 12.5% concentrations of PVAc exhibited a significant (P < 0.05) impact in reducing the respiration rate, ethylene production rate, weight loss, and maintaining firmness compared to the control sample. Furthermore, the study also investigated the potential acute toxicological and histological effects of the PVAc (12.5%) coated sample on mice. The results indicated that there were no harmful or lethal effects observed in the experimental mice. Therefore, the PVAc coating at concentrations of 10.0% and 12.5% proves to be beneficial in preserving the natural color of lemons and minimizing senescence during storage at (27 ± 2)°C.

Quercus robur wood veneer with pronounced natural color uniformity and stability by regulating the content of phenolic extractives

Wood is recognized as a promising raw material for house furnishings due to its good mechanical properties, relatively low density and weight and biodegradability. However, the natural color difference of wood veneer always induces value degradation. Therefore, accurate color regulation plays a pivotal role in producing high-value wood-based composites. In this study, a Quercus robur wood exhibiting a pronounced color variation was treated by an alkaline hydrogen peroxide (H2O2) homogenization process to regulate the content of phenolic extractives, and ferric chloride (FeCl3)-induced color modification to optimize the color. In order to minimize the chromatic disparity of the veneer, it simultaneously restores its initial hue and thus enhances its value. The color difference values of natural untreated Quercus robur veneer and homogenized toned veneer were assessed by using color testing based on the CIEL*a*b* 1976 system. The results demonstrated that the levels of lignin, hemicelluloses, and extractives in the toned veneers subjected to homogenization pretreatment exhibited varying degrees of reduction, along with a decrease in their affinity for iron ions. By assessing the colorfastness of homogenized, toned veneer through testing, the water and light resistance of the homogenized pretreated veneer is significantly superior to that of Quercus robur treated exclusively with iron salts. A higher level of color uniformity in the homogenized pretreated toned veneers, with the toned veneers treated with 0.16 mol/L iron salt exhibiting the closest resemblance to natural Quercus robur wood. This study not only reveals a novel methodology for chemically modifying the hue of wooden surfaces to achieve natural color uniformity but also presents a sustainable and facile approach to promote the high value-added utilization of wood.

Properties of encapsulated raspberry powder and its efficacy for improving the pH, colour quality and shelf life of modified atmosphere packaged chicken nuggets

ABSTRACT 1. Recent research has shown that encapsulated raspberry powder (RP) is a natural colourant for foodstuffs. However, no research has been conducted on its use in chicken nuggets. In addition, the effect of RP on products with and without phosphate addition is unknown. This study assessed the effects of RP (control, 0.5%, 1.0%) and phosphate (0.0%, 0.3%) on the pH and colour quality properties of nuggets. 2. In the production of RP, red raspberry (Rubus ideaus L.) juices were encapsulated using maltodextrin in a spray-dryer. Antioxidant activity, total anthocyanin, total phenolics, colour, moisture and pH analyses of the RP were performed. 3. Nuggets were packaged in modified atmosphere packaging (MAP; 40%CO2 + 60%N2) and were stored at 2.0 ± 0.5°C for 120 d. The pH and external and internal surface colour (L*, a*, b*, C* and h) values were measured on d 0, 15, 30, 45, 60, 75, 90, 105 and 120 of storage. 4. The addition of phosphate increased the pH in the samples, while these decreased with the addition of RP (p < 0.05). During storage, the highest pH were seen in the phosphate samples and the lowest in the nuggets with 1.0% RP addition (p < 0.05). 5. With the addition of phosphate, the external surface a* value of nuggets increased (p < 0.05). Depending on the level of RP added to the nuggets, the external surface L* value decreased and a* and b* values increased (p < 0.05). After d 30 of storage, the a* value increased in the samples with RP addition and this increase was higher in the with phosphate nuggets (p < 0.05). 6. The internal surface a* value increased with the addition of RP during nugget production (p < 0.05). The increase in a* value was greater in samples with added phosphate (p < 0.05). During storage, the highest a* values were seen in nuggets treated with phosphate + 0.1% RP (p < 0.05). The addition of RP to chicken nugget emulsion improved redness, colour stability and shelf life.

Influence of Low pH on the Microhardness and Roughness Surface of Dental Composite-A Preliminary Study.

Dental composites are gaining great popularity in restorative dentistry because of their aesthetic appeal and capacity to replicate the natural color of teeth. Nevertheless, their lifespan and durability rely on various factors, such as the polishing technique and the environmental conditions they are exposed to. The study aimed to assess the influence of the method of final polishing of dental composite on the surface roughness and microhardness of materials also considering the environment of different pHs. Disc-shaped samples (5 mm diameter and 2 mm thickness) have been prepared for microhardness and roughness tests from two dental composites: A2 Clearfil Majesty ES 2 Classic and A2D Clearfil Majesty Premium. One-third of samples were polished with polishing discs, OptiDisc, another one-third of samples were polished with Eve Diacomp Twist rubbers and polishing brush with diamond particles, and rest of the samples were stored without any polishing (the control group). Tested materials were incubated in distilled water or acidic buffer (pH = 2) for 3 weeks at a temperature of 37 °C. No statistically significant differences were found for roughness for the two materials tested after incubation in liquids. A decrease in Vicker microhardness was found for Clearfil Majesty ES 2 Classic after soaking in a low pH liquid, and no such relationship was found for Clearfil Majesty Premium. The improved resistance of these materials to the negative oral environment may result in the longer survival of composite restorations in patients with poor diet or diseases, causing a decrease in oral pH.

Traditional Fish Leather Dyeing Methods with Indigenous Arctic Plants

Along the Arctic and sub-Arctic coasts of Alaska, Siberia, north-eastern China, Hokkaido, Scandinavia and Iceland, people have dressed in clothes or worn shoes made of fish skin for millennia. (Within this article, the terms fish skin and fish leather are used to indicate different processes of the same material. Fish skin: Skin indicates the superficial dermis of an animal. Fish skin is referred to as the historical raw material that is tanned following traditional methods such as mechanical, oiling and smoking tanning, using materials such as bark, brain, urine, fish eggs and corn flour. Fish leather is used to refer that the fish skin has passed one or more stages of industrial vegetable or chrome tanning production and is ready to be used to produce leather goods). These items are often decorated with a rich colour palette of natural dyes provided by nature. In this study, minerals and raw materials of plant origin were collected from riverbanks and processed by Arctic seamstresses who operated as designers, biochemists, zoologists, and climatologists simultaneously. During our research, an international team of fashion, tanning and education specialists used local Arctic and sub-Arctic flora from Sweden, Iceland, and Japan to dye fish leather. Several plants were gathered and sampled on a small scale to test the process and determine the colours they generated based on the historical literature and verbal advice from local experts. This paper describes the process and illustrates the historical use of natural dyes by the Arctic groups originally involved in this craft, building on the traditional cultural heritage that has enabled us to develop sustainable dyeing processes. The results are promising and confirm the applicability of these local plants for dyeing fish skins, providing a basis for a range of natural dye colours from local Arctic flora. The aim is to develop a moderate-sized industrial production of fish leather in this colour palette to replace current unsustainable chemical dyeing processes. This project represents an innovation in material design driven by traditional technologies, addressing changes in interactions between humans and with our environment. The results indicate that new materials, processes, and techniques are often the fruitful marriage of fashion and historical research of traditional methods, helping the industry move towards a more sustainable future.

Long-term exposure to prometryn damages the visual system and changes color preference of female zebrafish (Danio rerio)

Color vision, initiated from the cone photoreceptors, is essential for fish to obtain environmental information. Although the visual impairment of triazine herbicide prometryn has been reported, data on the effect of herbicide such as prometryn on natural color sensitivity of fish is scarce. Here, zebrafish were exposed to prometryn (0, 1, 10, and 100 μg/L) from 2 h post-fertilization to 160 days post-fertilization, to explore the effect and underlying mechanism of prometryn on color perception. The results indicated that 10 and 100 μg/L prometryn shortened the height of red-green cone cells, and down-regulated expression of genes involved in light transduction pathways (arr3a, pde6h) and visual cycle (lrata, rpe65a); meanwhile, 1 μg/L prometryn increased all-trans-retinoic acid levels in zebrafish eyes, and up-regulated the expression of genes involved in retinoid metabolism (rdh10b, aldh1a2, cyp26a1), finally leading to weakened red and green color perception of female zebrafish. This study first clarified how herbicide such as prometryn affected color vision of a freshwater fish after a long-term exposure from both morphological and functional disruption, and its hazard on color vision mediated-ecologically relevant tasks should not be ignored.

Enhancing the stability of anthocyanins extracts through adsorption into nanoclays – development of a smart biohybrid sensor for intelligent food packaging or as natural food additive/preservative

Anthocyanins (ACNs) are bioactive compounds sensible to high temperature, light and highly reactive to pH changes. These natural pigments present different colors according to the environment pH, which enables its use as bio-based sensor to control microbial quality of fresh perishable foodstuff. In this work, a biohybrid material (BH) composed of anthocyanins extract from jambolan fruit (Syzygium cumini) stabilized by adsorption onto montmorillonite (Mt) was developed, characterized and tested to monitor freshness of shrimp. Anthocyanins were recovered from extract using Mt as adsorbent at pH 1.5, 2.5, and 3.5 and temperatures of 10 and 20 °C. Langmuir and pseudo-second-order kinetic models were adjusted to explain these adsorption mechanisms. ACNs’ adsorption increased with decreasing pH (p > 0.05) and increasing temperature. At 20 °C and pH 1.5, 93 % of ACNs were recovered from extract (adsorption of 212.04 mg of ACNs/g of Mt). The obtained BH presented good stability and color changing capacity when exposed to ammonia vapor at pH varying from 1 to 13. Freshness of shrimp was monitored with the BH, validating its potential to be used as ammonia sensing or pH indicators in intelligent packaging.

Per-acetic acid effect on separation of banana fiber and their dyeing with natural dyes

The fiber derived from the pseudo-stem of the banana plant is the subject of this investigation. It describes the processes involved in creating pseudo-stem fiber from bananas, such as fiber extraction, retting, and degumming. Banana fiber has been separated using per-acetic acid. To evaluate the efficacy of the process, the fiber's appearance and form have been altered. A homogeneous, spotless surface was observed under Scanning Electron Microscopy. Weight loss is the outcome of the treatment and absorbency increases. 3.66% of the weight loss is attributed to the per-acetic acid treatment. The fiber’s average diameter was reduced 81.9% compared to the raw fiber. Fourier transform infrared spectroscopy analysis was utilized to assess the chemical changes brought about by the treatment, which verified the presence of cellulose in the fiber. The separated fibers were colored using natural dyes, which were then assessed based on how well they characterized the color. The results demonstrated the use of natural colors derived from extracts of madder and myrobalan. The standard test indicates that ferrous sulfate (FeSO4) exhibits strong resistance to light, washing, and rubbing fastness, making it a viable mordant for achieving brown to black color.Graphical

Rehabilitation Using Implants with Sloped Platform Edge vs. Standard Platform with Guided Bone Regeneration: A Randomized Control Clinical Trial.

The purpose of this study was to evaluate the vertical bone loss after using different techniques: sloped implants or standard implants with guided bone regeneration. Patients with tooth gap and horizontal bone deficiency were randomly allocated to the test group (implants with sloped platform-SLP) and control group (standard design implants with guided bone regeneration-GBR). The primary outcome was bone loss (6 months after finishing the prosthetic treatment). Secondary outcomes included the following: patient-reported outcome measures (PROMs), post-operative edema, keratinized mucosa width, and pink aesthetic score (PES). The average bone loss at 6 months was 0.23 ± 0.15 mm and 1.03 ± 0.37 mm in the SLP and GBR groups, respectively. The SLP group was characterized by lower pain intensity the first 7 days (p < 0.001), lower post-operative edema (p < 0.001), lower consumption of NSAIDs on days 1, 3, 5, and 7 (p = 0.002, <0.001, <0.001, and 0.008), and lower total OHIP-14 (p = 0.047) on day 7. The keratinized mucosa width was 3.7 (3.4-4.0) mm and 2 (1.4-2.0) mm in the SLP and GBR groups, respectively. The preservation of the mesial, distal papillae, and the level of soft tissue correspondence were significantly higher in the SLP group (p = 0.003, 0.038, <0.001). In the SLP group, more natural color and better texture of soft tissues were found (p = 0.048, p = 0.041). The use of implants with a sloped platform resulted in superior outcomes compared to the standard-design implants with GBR.

Association Between Natural Hair Color, Race, and Alopecia.

Limited epidemiologic data has suggested direct associations between hair pigment, race, and incidence of alopecia areata (AA). Here, we examine the relationship between natural hair color, race, and the lifetime risk alopecia. In this case-control study, we included UK Biobank patients of all races and self-reported hair color with diagnoses of AA, androgenetic alopecia (AGA), or scarring alopecia (SA). Multivariable logistic regression was used to detect differences in lifetime risk. Findings reveal a significantly increased risk of AA among individuals with black hair compared to dark brown hair (OR 1.71 [95% CI 1.22-2.38], p < 0.001). Those with red or blonde hair showed a decreased risk of AA (0.74 [0.56-0.97]; 0.62 [0.41-0.95], p < 0.05). No racial differences in AA prevalence were observed among individuals with black hair. Darker hair colors may be associated with a higher risk of AA, lighter hair colors with a lower risk, and differences in hair color could contribute to previously noted racial variations in AA incidence, potentially influencing dermatologists' perspectives on the disease's epidemiology.

Multi‐omics reveal the molecular basis of LrAN2 overexpression in black goji callus promoting the excessive accumulation of petanin, a promising food blue colorant

AbstractLycium ruthenicum fruit (LRF) is a potential source of natural colorant in a wide pH range due to richness in monoacylated anthocyanin petanin. However, the yield of LRF largely lags behind the market demand in food industry. In this study, overexpressing LrAN2 (LrAN2OE), an anthocyanin activator in LRF, produced excessive acylated anthocyanins including petanin in L. ruthenicum callus (LRC). Physiological analysis indicates that LrAN2OE extensively orchestrate the redox homeostasis, including antioxidant enzymes system and antioxidants with low molecular weight. KEGG enrichment analysis indicates that LrAN2 hierarchically orchestrate the acylated anthocyanin biosynthesis in LRC at multi‐omics level, such as small RNAome, transcriptome, and metabolome. The anthocyanin yield of LrAN2OE callus cultured by 5% sucrose or glucose is significantly enhanced. Furthermore, the anthocyanin yield approach to 96.23 mg/g dry weight, approximately 3.5 folds of that in LRF, when LrAN2OE suspension cells are cultured in liquid MS medium supplement with 5% sucrose and 100 mM NaCl. Notably, anthocyanins extracted from LrAN2OE callus are stable in pH 1.0–2.0, pH 7.0, and pH 9.0, showing red or blue color within 30 days at 4°C. Our findings suggest that LrAN2 is perfect gene resource for metabolic engineering of acylated anthocyanins in LRC, a promising chassis producing acylated anthocyanins. Taken together, LRC metabolically engineered by LrAN2 is a potential source of natural food color, which facilitates to make up the shortfall of LRF as source of natural colorant in future food industry.

Amazon Fruits as Healthy Ingredients in Muscle Food Products: A Review.

When looking for new ingredients to process red meat, poultry, and fish products, it is essential to consider using vegetable resources that can replace traditional ingredients such as animal fat and synthetic antioxidants that may harm health. The Amazon, home to hundreds of edible fruit species, can be a viable alternative for new ingredients in processing muscle food products. These fruits have gained interest for their use as natural antioxidants, fat replacers, colorants, and extenders. Some of the fruits that have been tested include açai, guarana, annatto, cocoa bean shell, sacha inchi oil, and peach palm. Studies have shown that these fruits can be used as dehydrated products or as liquid or powder extracts in doses between 250 and 500 mg/kg as antioxidants. Fat replacers can be added directly as flour or used to prepare emulsion gels, reducing up to 50% of animal fat without any detrimental effects. However, oxidation problems of the gels suggest that further investigation is needed by incorporating adequate antioxidant levels. In low doses, Amazon fruit byproducts such as colorants and extenders have been shown to have positive technological and sensory effects on muscle food products. While evidence suggests that these fruits have beneficial health effects, their in vitro and in vivo nutritional effects should be evaluated in muscle food products containing these fruits. This evaluation needs to be intended to identify safe doses, delay the formation of key oxidation compounds that directly affect health, and investigate other factors related to health.