Β-carotene Production Research Articles

Bioactive Lipids in Dunaliella salina: Implications for Functional Foods and Health.

Dunaliella salina is a green microalga extensively explored for β-carotene production, while knowledge of its lipid composition is still limited and poorly investigated. Among lipids, polar lipids have been highlighted as bioactive phytochemicals with health-promoting properties. This research aimed to provide an in-depth lipidome profiling of D. salina using liquid and gas chromatography coupled with mass spectrometry. The lipid content was 6.8%, including phospholipids, glycolipids, betaine lipids, sphingolipids, triglycerides, diglycerides, and pigments. Among the total esterified fatty acids, 13.6% were 18:3 omega-3 and 14.7% were 18:1 omega-9. The lipid extract of D. salina showed anti-inflammatory activity by inhibiting cyclooxygenase-2 activity at 100 µg/mL, dose-dependent antioxidant scavenging activity, and antidiabetic activity by inhibiting α-glucosidase activity at 25 and 125 µg/mL. In conclusion, the lipid extract of D. salina has the potential to be used as a functional food ingredient or in the nutraceutical and cosmeceutical industries.

Enhancing carotenoid accumulation in Dunaliella bardawil by combined treatments with fulvic acid and optimized culture conditions

Natural carotenoids from microalgae have received more attention as an alternative source. In this study, fulvic acid (FA), a plant growth regulator, was used to enhance carotenoid accumulation in microalgae Dunaliella bardawil rich in lutein. However, the addition of FA promoted pigment synthesis but also exhibited an inhibitory effect on biomass. Therefore, the optimization of culture conditions was performed to further enhance carotenoid accumulation, including high light stress (10,000 lx) and the two-stage cultivation comprising 1-aminocyclopropane-1-carboxylic acid (ACC) and FA. Under both culture conditions, the growth inhibition caused by FA was alleviated, leading to a further increase in the contents of chlorophylls and carotenoids. HPLC analysis revealed that the production of lutein, α-carotene and β-carotene increased by 0.44-, 0.37- and 0.54-fold under the treatment of 400 mg/L FA with high light intensity and 0.91-, 1.15- 0.29-fold under the two-stage cultivation comprising 11 mM ACC and 500 mg/L FA. Furthermore, algal cells under FA treatment and the two-stage cultivation stained with Bodipy505/515 emitted stronger fluorescence under a laser confocal microscope, suggesting that lipid accumulation was increased. Additionally, the transcription levels of carotenogenic genes were also found to be up-regulated by qRT-PCR. These results indicated an enhancement in both the storage capacity and synthesis of carotenoids in D. bardawil. This study revealed the potential application of plant growth regulators in promoting carotenoid accumulation in D. bardawil which could be further improved by optimizing the culture conditions, providing a reference for efficient carotenoid production in microalgae.

Characterization of lycopene β-cyclase from Dunaliella bardawil for enhanced β-carotene production and salt tolerance

Dunaliella can accumulate more β-carotene (10 % or even more of the dry weight of cells) than any other species. Lycopene β-cyclase (LcyB) is the key enzyme in the catalysis of lycopene to β-carotene. In the present research, we used Escherichia coli BL21 (DE3) as host to construct two different types of engineering bacteria, one expressing the D. bardawil LcyB and the other expressing the orthologue Erwinia uredovora crtY. The catalytic ability of LcyB and CrtY were evaluated by comparing the β-carotene yields of the two E. coli BL21(DE3) strains, whose salt tolerance was simultaneously compared by cultivated them under different NaCl concentrations (1 %, 2 %, and 4 %). We also interfered with the LcyB gene to investigate the effect of LcyB in D. bardawil. Results displayed that the β-carotene yield of the LcyB-transformant significantly increased by about 48 % compared with the crtY-transformant. Additionally, LcyB was verified to be able to enhance the salt tolerance of E. coli BL21 (DE3). It is concluded that D. bardawil LcyB not only has better catalytic ability but also is able to confer salt tolerance to cells. Interfering D. bardawil LcyB induced the low expression of LcyB and the changes of growth and carotenoids metabolism in D. bardawil.

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.

Retargeting of heterologous enzymes results in improved β-carotene synthesis in Saccharomyces cerevisiae.

Carotenoids are a class of hydrophobic substances that are important as food and feed colorants and as antioxidants. The pathway for β-carotene synthesis has been expressed in various yeast species, albeit with rather low yields and titers. The inefficient conversion of phytoene to lycopene is often regarded as a bottleneck in the pathway. In this study, we aimed at the improvement of β-carotene production in Saccharomyces cerevisiae by specifically engineering the enzymatic reactions producing and converting phytoene. We show that phytoene is stored in intracellular lipid droplets, whereas the enzyme responsible for its conversion, phytoene dehydrogenase, CrtI, is located at the endoplasmic reticulum, like the bifunctional enzyme CrtYB that catalyses the reaction before and after CrtI. To improve the accessibility of phytoene for CrtI and to delay its storage in lipid droplets, we tested the relocation of CrtI and CrtYB to mitochondria. However, only the retargeting of CrtYB resulted in an improvement of the β-carotene content, whereas the mitochondrial variant of CrtI was not functional. Surprisingly, a cytosolic variant of this enzyme, which we obtained through the elimination of its carboxy-terminal membrane anchor, caused an increase in β-carotene accumulation. Overexpression of this CrtI variant in an optimized medium resulted in a strain with a β-carotene content of 79 mg g-1 cell dry weight, corresponding to a 76-fold improvement over the starting strain. The retargeting of heterologously expressed pathway enzymes improves β-carotene production in S. cerevisiae, implicating extensive inter-organellar transport phenomena of carotenoid precursors. In addition, strong overexpression of carotenoid biosynthetic enzymes and the optimization of cultivation conditions are required for high contents.

A novel mutation in non-constitutive lycopene beta cyclase (CstLcyB2a) from Crocus sativus modulates carotenoid/apocarotenoid content, biomass and stress tolerance in plants.

Mutation at A126 in lycopene-β-cyclase of Crocus (CstLcyB2a) sterically hinders its binding of δ-carotene without affecting lycopene binding, thereby diverting metabolic flux towards β-carotene and apocarotenoid biosynthesis. Crocus sativus, commonly known as saffron, has emerged as an important crop for research because of its ability to synthesize unique apocarotenoids such as crocin, picrocrocin and safranal. Metabolic engineering of the carotenoid pathway can prove a beneficial strategy for enhancing the quality of saffron and making it resilient to changing climatic conditions. Here, we demonstrate that introducing a novel mutation at A126 in stigma-specific lycopene-β-cyclase of Crocus (CstLcyB2a) sterically hinders its binding of δ-carotene, but does not affect lycopene binding, thereby diverting metabolic flux towards β-carotene formation. Thus, A126L-CstLcyB2a expression in lycopene-accumulating bacterial strains resulted in enhanced production of β-carotene. Transient expression of A126L-CstLcyB2a in C. sativus stigmas enhanced biosynthesis of crocin. Its stable expression in Nicotiana tabacum enhanced β-branch carotenoids and phyto-hormones such as abscisic acid (ABA) and gibberellic acids (GA's). N. tabacum transgenic lines showed better growth performance and photosynthetic parameters including maximum quantum efficiency (Fv/Fm) and light-saturated capacity of linear electron transport. Exogenous application of hormones and their inhibitors demonstrated that a higher ratio of GA4/ABA has positive effects on biomass of wild-type and transgenic plants. Thus, these findings provide a platform for the development of new-generation crops with improved productivity, quality and stress tolerance.

Induction of point and structural mutations in engineered yeast Saccharomyces cerevisiae improve carotenoid production.

β-Carotene is an attractive compound and that its biotechnological production can be achieved by using engineered Saccharomyces cerevisiae. In a previous study, we developed a technique for the efficient establishment of diverse mutants through the introduction of point and structural mutations into the yeast genome. In this study, we aimed to improve β-carotene production by applying this mutagenesis technique to S. cerevisiae strain that had been genetically engineered for β-carotene production. Point and structural mutations were introduced into β-carotene-producing engineered yeast. The resulting mutants showed higher β-carotene production capacity than the parental strain. The top-performing mutant, HP100_74, produced 37.6mg/L of β-carotene, a value 1.9 times higher than that of the parental strain (20.1mg/L). Gene expression analysis confirmed an increased expression of multiple genes in the glycolysis, mevalonate, and β-carotene synthesis pathways. In contrast, expression of ERG9, which functions in the ergosterol pathway competing with β-carotene production, was decreased in the mutant strain. The introduction of point and structural mutations represents a simple yet effective method for achieving mutagenesis in yeasts. This technique is expected to be widely applied in the future to produce chemicals via metabolic engineering of S. cerevisiae.

β-Carotene production from sugarcane molasses by a newly isolated Rhodotorula toruloides L/24-26-1.

Production of carotenoids by yeast fermentation is an advantaged technology due to its easy scaling and safety. Nevertheless, carotenoid production needs an economic culture medium and other efficient yeast stains. The study aims to isolate and identify a yeast strain capable of producing carotenoids using a cost-effective substrate. A new strain was identified asRhodotorula toruloidesL/24-26-1, which can produce carotenoids at different pretreated and unpretreated sugarcane molasses concentrations (40 and 80g/L). The highest biomass concentration (18.6 ± 0.6g/L) was reached in the culture using 80g/L of hydrolyzed molasses. On the other hand, the carotenoid accumulation reached the maximum value using pretreated molasses at 40g/L (715.4 ± 15.1µg/g d.w). In this case, the β-carotene was 1.5 times higher than that on the control medium. The yeast growth in molasses was not correlated with carotenoid production. The most outstanding production of The DPPH, ABTS, and FRAP tests demonstrated the antioxidant activity of the obtained carotenogenic extracts. This research demonstrated theR. toruloidesL/24-26-1 strain biotechnological potential for carotenoid compounds. The yeast produces carotenoids with antioxidant activity in an inexpensive medium, such as sulfuric acid pretreated and unpretreated molasses.

WITHDRAWN: 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.

A REVIEW ON THE β-CAROTENE: PRODUCTION, EXTRACTION, SYNTHESIS AND BIOLOGICAL PROPERTIES

The presence of double bonds gives β-carotene its distinctive hue, making it an oxygen-deficient isoprene-containing molecule. There are cyclic rings at both ends of the molecule. The present review was based on the production, extraction, synthesis and biological properties of β-carotene. Mammals can't produce carotenoids from scratch; therefore, they must get them from somewhere else. Algae, higher plants (in fruits and flowers as esters), fungi, and animals all have these yellow, red, and orange pigments in their natural forms. Carotenoids are found in human breast milk and can be modified through the mother's diet. Hexane, tetrahydrofuran, and acetone are examples of aprotic organic solvents that can be used for solvent-based extraction of -carotene from algae after and before they have been treated. The -carotene in algae, fungi, and plants can be extracted with the help of these solvents. The extraction process for -carotene is sped up and improved by the use of supercritical fluids. Increasing beta-carotene production can be accomplished by tailoring a number of environmental factors, including the type of organism used in the cultivation process, the amount of light available, the amount of salt present, the pH level, and the type and availability of carbon sources. Microalgae, plants, and fungus have all been optimised to increase their beta-carotene synthesis. It concluded that when administered in different doses, it has been shown to have effects like antioxidant and anti-inflammatory. it is also effective against cancer, cardiovascular diseases, Covid-19 and various other diseases.

Enhanced high β-carotene yeast cell production by Rhodotorula paludigena CM33 and in vitro digestibility in aquatic animals

This study assessed Rhodotorula paludigena CM33's growth and β-carotene production in a 22-L bioreactor for potential use as an aquatic animal feed supplement. Optimizing the feed medium's micronutrient concentration for high-cell-density fed-batch cultivation using glucose as the carbon source yielded biomass of 89.84 g/L and β-carotene concentration of 251.64 mg/L. Notably, using sucrose as the carbon source in feed medium outperforms glucose feeds, resulting in a β-carotene concentration of 285.00 mg/L with a similar biomass of 87.78 g/L. In the fed-batch fermentation using Sucrose Feed Medium, R. paludigena CM33 exhibited high biomass production rates (Qx) of 0.91 g/L.h and remarkable β-carotene production rates (Qp) of 2.97 mg/L.h. In vitro digestibility assays showed that R. paludigena CM33, especially when cultivated using sucrose, enhances protein digestibility affirming its suitability as an aquatic feed supplement. Furthermore, R. paludigena CM33's nutrient-rich profile and probiotic potential make it an attractive option for aquatic nutrition. This research highlights the importance of cost-effective carbon sources in large-scale β-carotene production for aquatic animal nutrition.

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.

Enhancing astaxanthin biosynthesis and pathway expansion towards glycosylated C40 carotenoids by Corynebacterium glutamicum

Astaxanthin, a versatile C40 carotenoid prized for its applications in food, cosmetics, and health, is a bright red pigment with powerful antioxidant properties. To enhance astaxanthin production in Corynebacterium glutamicum, we employed rational pathway engineering strategies, focused on improving precursor availability and optimizing terminal oxy-functionalized C40 carotenoid biosynthesis. Our efforts resulted in an increased astaxanthin precursor supply with 1.5-fold higher β-carotene production with strain BETA6 (18 mg g−1 CDW). Further advancements in astaxanthin production were made by fine-tuning the expression of the β-carotene hydroxylase gene crtZ and β-carotene ketolase gene crtW, yielding a nearly fivefold increase in astaxanthin (strain ASTA**), with astaxanthin constituting 72% of total carotenoids. ASTA** was successfully transferred to a 2 L fed-batch fermentation with an enhanced titer of 103 mg L−1 astaxanthin with a volumetric productivity of 1.5 mg L−1 h−1. Based on this strain a pathway expansion was achieved towards glycosylated C40 carotenoids under heterologous expression of the glycosyltransferase gene crtX. To the best of our knowledge, this is the first time astaxanthin-β-d-diglucoside was produced with C. glutamicum achieving high titers of microbial C40 glucosides of 39 mg L−1. This study showcases the potential of pathway engineering to unlock novel C40 carotenoid variants for diverse industrial applications.

Dunaliella β-Carotene Productivity Comparison Under In Vitro Conditions.

Some species of Dunaliella produce high levels of β-carotene, which is the largest natural Vitamin A source. β-carotene production in Dunaliella is expensive due to low yields obtained under culture conditions used. Since three decades ago synthetic β-carotene has dominated 98% of world market, even when synthetic is less bioactive than Dunaliella β-carotene molecule. In vitro experiments have been performed to increase β-carotene productivity in Dunaliella and some useful results have been obtained. In this review, culture conditions used in those experiments were compared to identify parameters that improved β-carotene productivity in Dunaliella. Comparison results show that β-carotene in vitro production can be increased regulating some specific culture conditions.

A comparison of metabolic engineering strategies applied in Yarrowia lipolytica for β-carotene production

A comparison of metabolic engineering strategies applied in Yarrowia lipolytica for β-carotene production

Using Omics Techniques to Analyze the Effects of Gene Mutations and Culture Conditions on the Synthesis of β-Carotene in Pantoea dispersa

β-carotene possesses antioxidant properties and holds significant research value. In our study, we have successfully identified a strain of Pantoea dispersa MSC14 which has the capability to produce β-carotene. By incorporating corn steep liquor powder into culture medium and employing mutagenesis breeding techniques, we have successfully increased the production of β-carotene in the MSC14 strain by 13.97% and 29.22%, respectively. To gain further insights, we conducted genomic and transcriptomics analyses. These analyses revealed a significant mutation in the gndA (6-phosphogluconate dehydrogenase) gene of the mutant strain 14P9, resulting in a 33.74% decrease in 6-phosphogluconate dehydrogenase activity. Using transcriptomics analysis, we investigated the impact of this mutation on β-carotene production and explored the interconnectedness between carbon metabolism, fatty acid metabolism, amino acid metabolism, and β-carotene synthesis. The up-regulation of the trxC (Thioredoxin-2) gene, as observed in both transcriptomics results, prompted us to construct strains that overexpress trxC. This manipulation resulted in a notable 15.89% increase in β-carotene production, highlighting the significant impact of of the trxC gene on the β-carotene content of Pantoea dispersa. In conclusion, our study has successfully identified Pantoea dispersa MSC14 as a proficient producer of β-carotene. Furthermore, we have uncovered two genes implicated in the biosynthesis of β-carotene. These findings enhance our understanding of β-carotene synthesis and provide valuable guidance for carotenoid biosynthesis.

Unlocking the potential of one-carbon gases (CO2, CO) for concomitant bioproduction of β-carotene and lipids

This study investigates the use of a Yarrowia lipolytica strain for the bioconversion of syngas-derived acetic acid into β-carotene and lipids. A two-stage process was employed, starting with the acetogenic fermentation of syngas by Clostridium aceticum, metabolising CO, CO2, H2, to produce acetic acid, which is then utilized by Y. lipolytica for simultaneous lipid and β-carotene synthesis. The research demonstrates that acetic acid concentration plays a pivotal role in modulating lipid profiles and enhancing β-carotene production, with increased acetic acid consumption leading to higher yields of these compounds. This approach showcases the potential of using one-carbon gases as substrates in bioprocesses for generating valuable bioproducts, providing a sustainable and cost-effective alternative to more conventional feedstocks and substrates, such as sugars.

Bioengineering of the Optimized Biosynthesis of Commercially Vital Carotenoids- Techno-Advanced Applications

Beta-carotene, a carotenoid found in plants, fungi, and algae, is a crucial antioxidant and anti-cancer agent. It is primarily derived from plants, algae, and microbes, but this method has drawbacks like high costs and low productivity. The growing demand for carotenoids has led to large-scale industrial manufacturing. However, extracting and synthesizing these chemicals can be costly and technical. Microbial synthesis offers a cost-effective alternative. Synthetic biology and metabolic engineering technologies have been used in various studies for the optimization of pathways for the overproduction of carotenoids. Four metabolic components are involved in carotenoid biosynthesis, central carbon (C), isoprene supplement, and cofactor metabolism. Metabolic engineering is a potential solution to enhance β-carotene production. This article explores the biochemical routes, methods used by natural microbial species, and metabolic engineering potential of microbial organisms for β-carotenoids production. Currently, Escherichia coli, certain euglena and yeast species are the primary microorganisms used in metabolic engineering, offering minimal environmental impact, cost-effective manufacturing, and high yield.

Enhanced β-Carotene Production in Mycolicibacterium neoaurum Ac-501/22 by Combining Mutagenesis, Strain Selection, and Subsequent Fermentation Optimization

A continuing interest of scientists regarding the development of new β-carotene production technologies is due to the high biological activity of this compound and its wide application range. Bacteria are considered among the possible β-carotene producers convenient for industrial use. The purpose of this study was to develop a Mycolicibacterium neoaurum strain with an enhanced ability for β-carotene production and to optimize the fermentation conditions to improve the final yield of the target compound. Using chemical mutagenesis with N-nitroso-N-methylurea along with further strain selection, a M. neoaurum strain Ac-501/22, whose productivity was 2.7-fold higher than that of the parental strain Ac-501, was developed. The effect of nitrogen and carbon sources as well as cultivation conditions on the growth of M. neoaurum Ac-501/22 and β-carotene production were studied to select the optimal fermentation regime. Due to an increase in the temperature of cultivation from 30 to 35 °C, replacement of glucose with glycerin (20.0 g/L) and degreased soybean flour with powdered milk (10.0 g/L), and increase in the urea content from 0.5 to 1.0 g/L, the level of β-carotene production was improved to 183.0 mg/kg that was 35% higher than in the control. Further strain fermentation in a 3 L bioreactor using an optimized medium with the pH level maintained at 7.0–7.2 and 50% pO2 provided the maximum output of the target compound (262.4 mg/kg of dry biomass) that confirmed the prospects of the developed strain as an industrial β-carotene producer.

Jeongeuplla avenae gen. nov., sp. nov., a novel β-carotene-producing bacterium that alleviates salinity stress in Arabidopsis.

A novel endophytic bacterium, designated DY-R2A-6T, was isolated from oat (Avena sativa L.) seeds and found to produces β-carotene. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain DY-R2A-6T had 96.3% similarity with Jiella aquimaris LZB041T, 96.0% similarity with Aurantimonas aggregate R14M6T and Aureimonas frigidaquae JCM 14755T, and less than 95.8% similarity with other genera in the family Aurantimonadaceae. The complete genome of strain DY-R2A-6T comprised 5,929,370 base pairs, consisting of one full chromosome (5,909,198 bp) and one plasmid (20,172 bp), with a G + C content was 69.1%. The overall genome-related index (OGRI), including digital DNA-DNA hybridization (<20.5%), ANI (<79.2%), and AAI (<64.2%) values, all fell below the thresholds set for novel genera. The major cellular fatty acids (>10%) of strain DY-R2A-6T were C16:0, C19:0 cyclo ω8c, and summed feature 8 (C18:1ω7c and/or C18:1ω6c). Ubiquinone-10 was the main respiratory quinone. We identified the gene cluster responsible for carotenoid biosynthesis in the genome and found that the pink-pigment produced by strain DY-R2A-6T is β-carotene. In experiment with Arabidopsis seedlings, co-cultivation with strain DY-R2A-6T led to a 1.4-fold increase in plant biomass and chlorophyll content under salt stress conditions, demonstrating its capacity to enhance salt stress tolerance in plants. Moreover, external application of β-carotene to Arabidopsis seedlings under salt stress conditions also mitigated the stress significantly. Based on these findings, strain DY-R2A-6T is proposed to represent a novel genus and species in the family Aurantimonadaceae, named Jeongeuplla avenae gen. nov., sp. nov. The type strain is DY-R2A-6T (= KCTC 82985T = GDMCC 1.3014T). This study not only identified a new taxon but also utilized genome analysis to predict and confirm the production of β-carotene by strain DY-R2A-6T. It also demonstrated the ability of this strain to enhance salt stress tolerance in plants, suggesting potential application in agriculture to mitigate environmental stress in crops.