An overview of β-carotene production: Current status and future prospects

Utilizing carboxymethyl cellulose to assist soy protein isolate in the formation of emulsion to deliver β-carotene: Exploring the correlation between interfacial behavior and emulsion stability

This study investigated the effects of carboxymethyl cellulose (CMC) adsorption on the interfacial properties of soy protein isolate (SPI) and its correlation with emulsion stability. The findings revealed that SPI-CMC emulsions exhibited reduced zeta potential and particle size compared with SPI emulsion alone. Molecular docking analysis suggested that the enhanced stability of SPI-CMC emulsions was primarily due to hydrogen bonding and electrostatic interactions between SPI and CMC. Notably, the encapsulation efficiency of β-carotene in SPI-CMC emulsions increased by 47.74 % at pH 4.0 with 0.4 % CMC and by 39.55 % at pH 5.0 with 0.5 % CMC compared to SPI emulsion. Stability analyses demonstrated that at pH 4.0, the SPI-CMC interfacial layer formed by hydrogen bonding and electrostatic interactions effectively protected β-carotene from external degradation factors. At pH 5.0, steric hindrance facilitated the formation of a SPI-CMC network structure, increasing the path length for oxidants to reach the oil droplet interface. These distinct binding mechanisms in SPI-CMC emulsions effectively prolonged oil droplet digestion and regulated the release of free fatty acids. The resulting emulsion exhibited slow and sustained lipid release and digestion kinetics, making it a suitable model for designing sustained-release nutritional supplements.

Enhancing the nutritional value and caliber of silver carp surimi by adding β-carotene: Insights into the gel characteristics, protein structure, and digestive properties

To investigate the effects of β-carotene on the gelling and digestion properties of surimi gels and the underlying molecular mechanisms, the gel properties, moisture distribution, rheological properties, secondary structure and microstructure were determined at different β-carotene concentrations (0 % ∼ 0.1 %). The results indicated that β-carotene levels from 0.02 % to 0.06 % were positively correlated with gel properties, and the storage modulus (G') gradually increased during heating. This was attributed primarily to the conversion of α-helix to β-sheet structures and the intensification of hydrophobic interactions, resulting in a more compact microstructure. Most importantly, at an additional level of 0.06 %, the digestibility did not significantly decrease with increasing gel properties. Moreover, the antioxidant activity of the hybrid gels subjected to gastrointestinal digestion was also enhanced. The present study provides a theoretical foundation for incorporating β-carotene into surimi which will provide more nutritious products.

Biosynthesis of Edible Terpenoids: Hosts and Applications

Microbial foods include microbial biomass, naturally fermented foods, and heterologously synthesized food ingredients derived from microbial fermentation. Terpenoids, using isoprene as the basic structure, possess various skeletons and functional groups. They exhibit diverse physicochemical properties and physiological activities, such as unique flavor, anti-bacterial, anti-oxidant, anti-cancer, and hypolipemic, making them extensively used in the food industry, such as flavor, fragrance, preservatives, dietary supplements, and medicinal health food. Compared to traditional strategies like direct extraction from natural species and chemical synthesis, microbial cell factories for edible terpenoids have higher titers and yields. They can utilize low-cost raw materials and are easily scaling-up, representing a novel green and sustainable production mode. In this review, we briefly introduce the synthetic pathway of terpenoids and the applications of microbial cell factories producing edible terpenoids. Secondly, we highlight several typical and non-typical microbial chassis in edible terpenoid-producing cell factories. In addition, we reviewed the recent advances of representative terpenoid microbial cell factories with a gram-scale titer in food flavor, food preservation, nutritional enhancers, and medicinal health foods. Finally, we predict the future directions of microbial cell factories for edible terpenoids and their commercialization process.

Substrate-dependent lipid and β-carotene production in engineered Yarrowia lipolytica: a comparative study

This study evaluates the influence of various substrates (glucose, glycerol, and acetic acid) on the growth and metabolite production of Yarrowia lipolytica in fed-batch bioreactors. The primary aim is to understand how substrate choice impacts lipid and β-carotene production, critical for bioenergy and bioproducts. The study demonstrates that the choice of substrate significantly influences biomass yield, lipid content, and β-carotene levels. Among the substrates tested, glycerol yielded the highest biomass concentration of 5.31 g/L. Glucose led to the highest lipid content, with a yield of 35.8% (g lipids/g biomass), while acetic acid resulted in the highest lipid concentration, reaching 1.42 g/L. In terms of β-carotene production, glucose showed the highest content per cell at 63.3 mg/g, whereas glycerol led to the highest overall concentration of 202 mg/L. These findings highlight Y. lipolytica's versatility and potential as a flexible platform to produce lipids and β-carotene, which are essential for developing sustainable biofuels and bioproducts. The study underscores the significant variations in metabolite production based on substrate choice, emphasizing on the importance of tailored strategies to optimize industrial applications. Further research may explore optimizing fermentation conditions to enhance production yields, making this yeast a viable option for various biotechnological applications.

Evaluation of Green and Biobased Solvent Systems for the Extraction of β-Carotene and Lipids from Rhodosporidium toruloides

Oleaginous microorganisms are promising for the biotechnological production of valuable hydrophobic bioactive components. For an environmentally friendly extraction, we evaluated a two-step process for β-carotene and lipid isolation from wet Rhodosporidium toruloides biomass using biphasic green and biobased solvent systems: 2-methyl tetrahydrofuran (2-MeTHF) or cyclopentyl-methyl-ether (CPME) with ethanol or 1-butanol and water. Initially, components were extracted with a single-phase solvent mixture, followed by separating hydrophobic target components from polar impurities via phase separation. We employed the Conductor-like Screening Model for Real Solvents (COSMO-RS) to predict the solubility of β-carotene and select compositions with higher solubility. Our study highlights the potential of these solvent systems for extracting hydrophobic components and the importance of understanding the system's liquid-liquid equilibria for effective process design. We present a framework for evaluating new solvent systems for extracting hydrophobic bioactive compounds by demonstrating the impact of solvent composition selection on extraction yields and solvent consumption.

Transcriptomic and metabolomic analyses reveal the positive effect of moderate concentration of sodium chloride treatment on the production of β-carotene, torulene, and torularhodin in oleaginous red yeast Rhodosporidiobolus odoratus XQR

Carotenoids, a family of lipid-soluble pigments, have garnered growing interest for their health-promoting benefits and are widely utilized in the food, feed, pharmaceutical, and cosmetic industries. Rhodosporidiobolus odoratus, a representative oleaginous red yeast, is considered a promising alternative for producing high-value carotenoids including β-carotene, torulene, and torularhodin. Here, the impact of varying concentrations of NaCl treatments on carotenoid contents in R. odoratus XQR after 120 h of incubation was examined. The results indicated that, as compared to the control (59.37 μg/gdw), the synthesis of total carotenoids was significantly increased and entirely suppressed under low-to-moderate (0.25 mol/L: 68.06 μg/gdw, 0.5 mol/L: 67.62 μg/gdw, and 0.75 mol/L: 146.47 μg/gdw) and high (1.0, 1.25, and 1.5 mol/L: 0 μg/gdw) concentrations of NaCl treatments, respectively. Moreover, the maximum production of β-carotene (117.62 μg/gdw), torulene (21.81 μg/gdw), and torularhodin (7.04 μg/gdw) was achieved with a moderate concentration (0.75 mol/L) of NaCl treatment. Transcriptomic and metabolomic analyses suggested that the increase in β-carotene, torulene, and torularhodin production might be primarily attributed to the up-regulation of some key protein-coding genes involved in the terpenoid backbone biosynthesis (atoB, HMGCS, and mvaD), carotenoid biosynthesis (crtYB and crtI), and TCA cycle (pckA, DLAT, pyc, MDH1, gltA, acnA, IDH1/2, IDH3, sucA, sucB, sucD, LSC1, SDHA, and fumA/fumB). The present study not only demonstrates a viable method to concurrently increase the production of β-carotene, torulene, torularhodin, and total carotenoids in R. odoratus XQR, but it also establishes a molecular foundation for further enhancing their production through genetic engineering.

Bacterial Pigments as a Promising Alternative to Synthetic Colorants: From Fundamentals to Applications

Pigments find widespread application in the fields of food, medicine, textiles, and cosmetics. At present, synthetic colorants dominate the global pigment market. However, the environmental and health hazards associated with synthetic colorants have spurred extensive research on eco-friendly and safe alternatives. Natural pigments are particularly intriguing for meeting consumer demands and sustainable development, as they not only exhibit various vibrant color shades without discernible toxic side effects but also offer additional healthful features such as antibacterial, antioxidant, anticancer, and antiviral properties compared with their synthetic counterparts. Among natural sources, bacterial strains share distinct advantages for large-scale pigment production because of their intrinsic robustness of cellular metabolic systems. This review comprehensively outlines the bacterial sources, extraction and purification methods, structural characteristics, biological activities, and potential applications of typical pigments, including but not limited to violacein, indigoidine, melanin, carotenoids, prodigiosin, and rhodopsin. Additionally, it underscores the primary obstacles to the development and production of bacterial pigments for commercial applications, discussing feasible strategies for overcoming production bottlenecks. This work also provides valuable insights for the scientific and rational advancement of bacterial pigment development.

Enhancement of skin localization of β-carotene from red fruit (Pandanus conoideus Lam.) using solid dispersion-thermoresponsive gel delivered via polymeric solid microneedles

Red fruit (Pandanus conoideus Lam.) boasts high β-carotene (BC) content, often consumed orally. However, absorption issues and low bioavailability due to food matrix interaction have led to transdermal delivery exploration. Nevertheless, BC has a short skin retention time. To address these limitations, this study formulates a β-carotene solid dispersion (SD-BC) loaded thermoresponsive gel combined with polymeric solid microneedles (PSM) to enhance in vivo skin bioavailability. Characterization of SD-BC includes saturation solubility, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and in vitro release. Characterization of SD-BC thermoresponsive gel includes gelation temperature, viscosity, rheological behaviour, pH, bio-adhesiveness, spreadability, and extrudability. PSM's mechanical properties and insertion capability were assessed. Ex vivo and in vivo dermato-pharmacokinetic studies, drug content, hemolysis, and skin irritation assessments were conducted to evaluate overall performance. Results confirm amorphous SD-BC formation, enhancing solubility. Both SD-BC thermoresponsive gel and PSM exhibit favourable characteristics, including rheological properties and mechanical strength. In vitro release studies showed a seven-fold increase in BC release compared to plain hydrogel. SD-BC thermoresponsive gel combined with PSM achieves superior ex vivo permeation (Cmax = 305.43 ± 32.07 µg.mL-1) and enhances in vivo dermato-pharmacokinetic parameters by 200-400 %. Drug content, hemolysis, and skin irritation studies confirmed its safety and non-toxicity.

Enhancing microbial CO2 electrocatalysis for multicarbon reduction in a wet amine-based catholyte

Microbial CO2 electroreduction (mCO2ER) offers a promising approach for producing high-value multicarbon reductants from CO2 by combining CO2 fixing microorganisms with conducting materials (i. e., cathodes). However, the solubility and availability of CO2 in an aqueous electrolyte pose significant limitations in this system. This study demonstrates the efficient production of long-chain multicarbon reductants, specifically carotenoids (~C40), within a wet amine-based catholyte medium during mCO2ER. Optimizing the concentration of the biocompatible CO2 absorbent, monoethanolamine (MEA), led to enhanced CO2 fixation in the electroautotroph bacteria. Molecular biological analyses revealed that MEA in the catholyte medium redirected the carbon flux towards carotenoid biosynthesis during mCO2ER. The faradaic efficiency of mCO2ER with MEA for carotenoid production was 4.5-fold higher than that of the control condition. These results suggest the mass transport bottleneck in bioelectrochemical systems could be effectively addressed by MEA-assissted mCO2ER, enabling highly efficient production of valuable products from CO2.

Efficient β-carotene production in engineered Saccharomyces cerevisiae using simple sugars and agricultural waste-based carbon and nitrogen sources

β-carotene, a precursor to vitamin A, holds significant promise for health and nutrition applications. This study introduces an optimized approach for β-carotene production in Saccharomyces cerevisiae, leveraging metabolic engineering and a novel use of agricultural waste. The GAL80 gene deletion facilitated efficient β-carotene synthesis from sucrose, avoiding the costly galactose induction, and achieved titers up to 727.8 ± 68.0 mg/L with content levels of 71.8 ± 0.4 mg/g dry cell weight (DCW). Furthermore, the application of agricultural by-products, specifically molasses and fish meal as carbon and nitrogen sources, was investigated. This approach yielded a substantial β-carotene titer of 354.9 ± 8.2 mg/L and a content of 60.5 ± 4.3 mg/g DCW, showcasing the potential of these sustainable substrates for industrial-scale production. This study sets a new benchmark for cost-effective, green manufacturing of vital nutrients, demonstrating a scalable, eco-friendly alternative for β-carotene production.

Strategies for the efficient biosynthesis of β-carotene through microbial fermentation

β-Carotene is an orange fat-soluble compound, which has been widely used in fields such as food, medicine and cosmetics owing to its anticancer, antioxidant and cardiovascular disease prevention properties. Currently, natural β-carotene is mainly extracted from plants and algae, which cannot meet the growing market demand, while chemical synthesis of β-carotene cannot satisfy the pursuit for natural products of consumers. The β-carotene production through microbial fermentation has become a promising alternative owing to its high efficiency and environmental friendliness. With the rapid development of synthetic biology and in-depth study on the synthesis pathway of β-carotene, microbial fermentation has shown promising applications in the β-carotene synthesis. Accordingly, this review aims to summarize the research progress and strategies of natural carotenoid producing strain and metabolic engineering strategies in the heterologous synthesis of β-carotene by engineered microorganisms. Moreover, it also summarizes the adoption of inexpensive carbon sources to synthesize β-carotene as well as proposes new strategies that can further improve the β-carotene production.

Characterization of a novel recombinant D-mannose isomerase from Bifidobacterium bifidum and its catalytic mechanism

Due to the increasing demand for health-conscious and environmentally friendly products, D-mannose has gained significant attention as a natural, low-calorie sweetener. The use of D-mannose isomerases (D-MIases) for D-mannose production has emerged as a prominent area of research, offering superior advantages compared with conventional methods such as plant extraction and chemical synthesis. In this study, a gene encoding D-MIase was cloned from Bifidobacterium and expressed in E. coli BL21 (DE3). The heterologously expressed enzyme, Bifi-mannose, formed a trimer with a molecular weight of 146.3 kDa and a melting temperature (Tm) of 63.39 ± 1.3 °C. Bifi-mannose exhibited optimal catalytic activity at pH 7.5 and 55 °C, and retained more than 80% of its activity after a 3-hour incubation at 55 °C, demonstrating excellent thermal stability. The Km, Vmax, and kcat/Km values of Bifi-mannose for D-fructose isomerization were determined as 538.7 ± 62.5 mM, 11.7 ± 0.9 μmol·mg1·s1, and 1.02 ± 0.3 mM1·s1, respectively. Notably, under optimized conditions, catalytic yields of 29.4, 87.1, and 148.5 mg·mL1 were achieved when using 100, 300, and 500 mg·mL1 of D-fructose as substrates, resulting in a high conversion rate (29%). Furthermore, kinetic parameters and molecular docking studies revealed that His387 residue primarily participates in the opening of the pyranose ring, while His253 acts as a basic catalyst in the isomerization process.

Challenges and prospects of yeast-based microbial oil production within a biorefinery concept

Biodiesel, unlike to its fossil-based homologue (diesel), is renewable. Its use contributes to greater sustainability in the energy sector, mainly by reducing greenhouse gas emissions. Current biodiesel production relies on plant- and animal-related feedstocks, resulting in high final costs to the prices of those raw materials. In addition, the production of those materials competes for arable land and has provoked a heated debate involving their use food vs. fuel. As an alternative, single-cell oils (SCOs) obtained from oleaginous microorganisms are attractive sources as a biofuel precursor due to their high lipid content, and composition similar to vegetable oils and animal fats. To make SCOs competitive from an economic point of view, the use of readily available low-cost substrates becomes essential. This work reviews the most recent advances in microbial oil production from non-synthetic sugar-rich media, particularly sugars from lignocellulosic wastes, highlighting the main challenges and prospects for deploying this technology fully in the framework of a Biorefinery concept.

RP-HPLC Separation and 1H NMR Identification of a Yellow Fluorescent Compound-Riboflavin (Vitamin B2)-Produced by the Yeast Hyphopichia wangnamkhiaoensis

The yeast Hyphopichia wangnamkhiaoensis excretes a brilliant yellow fluorescent compound into its growth culture. In this study, we isolated and identified this compound using reverse-phase high-performance liquid chromatography-diode array detector (RP-HPLC-DAD) as well as 1H NMR and UV-Vis spectroscopy. Two of the three RP-HPLC-DAD methods used successfully separated the fluorescent compound and involved (1) a double separation step with isocratic flow elution, first on a C18 column and later on a cyano column, and (2) a separation with a linear gradient elution on a phenyl column. The wavelengths of maximum absorption of the fluorescent compound-containing HPLC fractions (~224, 268, 372, and 446 nm) are in good agreement with those exhibited by flavins. The 1H NMR spectra revealed methyl (δ 2.30 and 2.40) and aromatic proton (δ 7.79 and 7.77) signals of riboflavin. The 1H NMR spectra of the samples spiked with riboflavin confirmed that the brilliant yellow fluorescent compound is riboflavin. The maximum excitation and emission wavelengths of the fluorescent compound were 448 and 528 nm, respectively, which are identical to those of riboflavin.

Enhancement of β-carotene content in Chlamydomonas reinhardtii by expressing bacterium-driven lycopene β-cyclase

β-Carotene is one of the economically important carotenoids, having functions as the antioxidant to remove harmful free radicals and as the precursor for vitamin A and other high-valued xanthophyll such as zeaxanthin and astaxanthin. Lycopene cyclase plays an important role in the branching of β-carotene and α-carotene. Aiming to develop the microalgae with enhanced β-carotene productivity, the CrtY gene from bacterium Pantoea agglomerans was integrated into Chlamydomonas reinhardtii. The lycopene-producing E. coli harboring CrtY gene produced 1.59 times of β-carotene than that harboring DsLcyb1 from Dunaliella salina (a microalga with abundant β-carotene), confirming the superior activity of CrtY on β-carotene biosynthesis. According to the pigment analysis by HPLC, in microalgal transformants that were confirmed by molecular analysis, the expression of CrtY significantly increased β-carotene content from 12.48 mg/g to 30.65 mg/g (dry weight), which is about 2.45-fold changes. It is noted that three out of five transformants have statistically significant higher amount of lutein, even though the increment was 20% in maximum. Besides, no growth defect was observed in the transformants. This is the first report of functional expression of prokaryotic gene in eukaryotic microalgae, which will widen the gene pool targeting carotenoids biosynthesis using microalgae as the factory and thereby provide more opportunity for high-valued products engineering in microalgae.

Characterization of polysaccharide from Lonicera japonica Thunb leaves and its application in nano-emulsion

The polysaccharides in honeysuckle leaves (PHL) were separated and characterized for the first time. The nano-emulsion stabilized by PHL and whey protein isolate (WPI) were also fabricated based on the ultrasonic method. The results indicated that PHL was mainly composed of glucose (47.40 mol%), galactose (19.21 mol%) and arabinose (20.21 mol%) with the weight-average molecular weight of 137.97 ± 4.31 kDa. The emulsifier concentration, WPI-to-PHL ratio, ultrasound power and ultrasound time had significant influence on the droplet size of PHL-WPI nano-emulsion. The optimal preparation conditions were determined as following: emulsifier concentration, 1.7%; WPI/PHL ratio, 3:1; ultrasonic power, 700 W; ultrasonic time, 7 min. Under the above conditions, the median diameter of the obtained nano-emulsion was 317.70 ± 5.26 nm, close to the predicted value of 320.20 nm. The protective effect of PHL-WPI emulsion on β-carotene against UV irradiation was superior to that of WPI emulsion. Our results can provide reference for the development of honeysuckle leaves.

Characterization of a Dihydromyricetin/α-Lactoalbumin Covalent Complex and Its Application in Nano-emulsions

A dihydromyricetin (DMY)/α-lactoalbumin (α-La) covalent complex was prepared and characterized, and its application in nano-emulsions was also evaluated in this study. The results suggested that the covalent complex could be obtained using the alkaline method. The UV and IR spectra confirmed the formation of the covalent complex, and the amount of DMY added was positively correlated with the total phenol content of the complex. The complex had an outstanding 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS)-radical-scavenging ability, reducing power and α-glucosidase inhibitory activity, which were positively related to its total phenol content. The complex could be used as an emulsifier to stabilize the β-carotene-loaded nano-emulsion. The stability and β-carotene-protective capacity of the nano-emulsion stabilized by the complex were also positively related to the total phenol content of the complex, being higher than those of the nano-emulsion developed using α-La. Our results provide a reference for the construction of a new food delivery system and extend the applications of α-La and DMY in foods.

Microalgae, Seaweeds and Aquatic Bacteria, Archaea, and Yeasts: Sources of Carotenoids with Potential Antioxidant and Anti-Inflammatory Health-Promoting Actions in the Sustainability Era

Carotenoids are a large group of health-promoting compounds used in many industrial sectors, such as foods, feeds, pharmaceuticals, cosmetics, nutraceuticals, and colorants. Considering the global population growth and environmental challenges, it is essential to find new sustainable sources of carotenoids beyond those obtained from agriculture. This review focuses on the potential use of marine archaea, bacteria, algae, and yeast as biological factories of carotenoids. A wide variety of carotenoids, including novel ones, were identified in these organisms. The role of carotenoids in marine organisms and their potential health-promoting actions have also been discussed. Marine organisms have a great capacity to synthesize a wide variety of carotenoids, which can be obtained in a renewable manner without depleting natural resources. Thus, it is concluded that they represent a key sustainable source of carotenoids that could help Europe achieve its Green Deal and Recovery Plan. Additionally, the lack of standards, clinical studies, and toxicity analysis reduces the use of marine organisms as sources of traditional and novel carotenoids. Therefore, further research on the processing of marine organisms, the biosynthetic pathways, extraction procedures, and examination of their content is needed to increase carotenoid productivity, document their safety, and decrease costs for their industrial implementation.

Simultaneous Production of Cellulase and β-Carotene in the Filamentous Fungus Trichoderma reesei

β-Carotene is an indispensable additive in beverage, cosmetic, feed, and pharmaceutical production. The fermentation industry annually generates abundant waste mycelia from Trichoderma reesei (T. reesei), a pivotal industrial strain for cellulase and heterologous protein production. In this study, we constructed a T. reesei cell factory for β-carotene production for the first time. Four key enzymes, CarRP, CarB, GGS1/CrtE, and HMG1, were overexpressed in T. reesei. The concentrations of medium components, including tryptone and glucose, were optimized. The modified strain accumulated β-carotene at a titer of 218.8 mg/L in flask culture. We achieved cellulase production (FPase, 22.33 IU/mL) with the concomitant production of β-carotene (286.63 mg/L) from T. reesei in a jar. Overall, this study offers a novel and unique approach to address the costly waste mycelium management process using T. reesei industrial strains that simultaneously produce proteins and carotenoids.

Whey Protein Isolate-Mesona chinensis Polysaccharide Conjugate: Characterization and Its Applications in O/W Emulsions

Mesona chinensis polysaccharide (MCP), a common thickener, stabilizer and gelling agent in food and pharmaceuticals, also has antioxidant, immunomodulatory and hypoglycemic properties. Whey protein isolate (WPI)-MCP conjugate was prepared and used as a stabilizer for O/W emulsion in this study. FT-IR and surface hydrophobicity results showed there could exist interactions between -COO- in MCP and -NH³⁺ in WPI, and hydrogen bonding may be involved in the covalent binding process. The red-shifted peaks in the FT-IR spectra suggested the formation of WPI-MCP conjugate, and MCP may be bound to the hydrophobic area of WPI with decreasing surface hydrophobicity. According to chemical bond measurement, hydrophobic interaction, hydrogen bond and disulfide bond played the main role in the formation process of WPI-MCP conjugate. According to morphological analysis, the O/W emulsion formed by WPI-MCP had a larger size than the emulsion formed by WPI. The conjugation of MCP with WPI improved the apparent viscosity and gel structure of emulsions, which was concentration-dependent. The oxidative stability of the WPI-MCP emulsion was higher than that of the WPI emulsion. However, the protection effect of WPI-MCP emulsion on β-carotene still needs to be further improved.

The Prospects of Algae-Derived Vitamins and Their Precursors for Sustainable Cosmeceuticals

Aquatic algae are a rich source of a wide range of bioproducts intended to compete for a sizable global market share. Thanks to the gradual shift towards the use of natural products, microalgae-derived bioactive compounds offer an ecofriendly and vegan option to the cosmeceutical sector, whose products aim to improve skin health but currently consist of mostly synthetic chemicals. In particular, algae-derived vitamins and their precursors are being explored and widely used in the cosmeceuticals industry as compounds that contain biologically active ingredients with therapeutic benefits. The present review highlights the current strategies for industrial production of an array of vitamins from algae for cosmeceutical applications. When compared to traditional plant sources, algae have been found to accumulate vitamins, such as A, B1, B2, B6, B12, C and E, in high concentrations. The purpose of this review is to provide context for the development of a green and sustainable algae-derived bioeconomy by summarizing and comparing the current market for vitamins and precursors derived from algae, as well as presenting novel strategies and key findings from the most recent research in this area. Emphasis is placed on novel biotechnological interventions that encompass genetic modifications, genetic engineering, and media development to enhance vitamin biosynthesis.

The Fabrication and Characterization of Pickering Emulsion Gels Stabilized by Sorghum Flour

Pickering emulsion gels have potential application as solid fat substitutes and nutraceutical carriers in foods, but a safe and easily available food-derived particle emulsifier is the bottleneck that limits their practical application. In this study, the function of sorghum flour as a particle emulsifier to stabilize the oil-in-water (O/W) Pickering emulsion gels with medium chain triglycerides (MCT) in the oil phase was introduced. Sorghum flour had suitable size distribution (median diameter, 21.47 μm) and wettability (contact angle, 38°) and could reduce the interfacial tension between MCT and water. The oil phase volume fraction (φ) and the addition amount of sorghum flour (c) had significant effects on the formation of Pickering emulsion gels. When c ≥ 5%, Pickering emulsion gels with φ = 70% could be obtained. Microstructure analysis indicated that sorghum flour not only played an emulsifying role at the O/W interface but also prevented oil droplets from coalescing through its viscous effect in the aqueous phase. With increases in c, the droplet size of the emulsion gel decreased, its mechanical properties gradually strengthened, and its protective effect on β-carotene against UV irradiation also improved.

Plasma-activated water promoted the aggregation of Aristichthys nobilis myofibrillar protein and the effects on gelation properties

Plasma is a new technology used to modify myofibrillar proteins (MPs) structure and promote protein aggregation. In order to study the mechanism of plasma modifying MPs thus the effects on qualities of MP gels, MPs were extracted by 0.6 M NaCl solution prepared with plasma-activated water (PAW) at different treatment time (0 s, 30 s, 60 s, 120 s, 240 s). With the prolonged PAW treatment time from 0 to 240 s, the pH values of natural MP solutions decreased significantly from 5.91 to 2.61 (P < 0.05), the H₂O₂ concentration in PAW increased from 0 to 70.82 μg/L (P < 0.05), and the net negative charges of MPs first decreased and then increased (P < 0.05). In addition, PAW caused significantly (P < 0.05) weakened ionic bonds and enhanced hydrophobic interactions, which promoted the aggregation and gelation of MPs thus forming MP gel with higher gel strength and a denser three-dimensional network. Furthermore, Raman spectra and intrinsic fluorescence suggested that PAW promoted the unfolding of MP structures and transformation from α-helixes and random coils to β-sheets and β-turns. Dynamic rheology indicated a gradually increased storage modulus and shortened degradation time of MPs with an increasing treatment time of PAW. Furthermore, PAW modification significantly improved the water holding capacity of MPs gels. These results demonstrated that the declined pH of MP solutions induced by PAW and increased H₂O₂ in PAW altered the ζ-potential of MP solutions and promoted the unfolding and aggregation of MPs during heating via hydrophobic interactions, ultimately enhancing gelling properties of MPs. The present work suggested the potential use of PAW in preparing freshwater MP gels with high quality.

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pH values of MP solutions were declined gradually by PAW with the treatment time.

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The H₂O₂ concentration in PAW increased gradually with the treatment time.

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PAW promoted the unfolding of MPs and formation of β-sheets.

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PAW weakened the ionic bonds and enhanced the hydrophobic interactions among MPs.

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PAW₆₀ showed the highest WHC and protein solubility contributed by hydrogen bonds.