Publications by authors named "Guojie Jin"

The objective of this study was to investigate the mechanism underlying LW-1-induced resistance to TMV in wild-type and salicylic acid (SA)-deficient NahG transgenic tobacco plants. Our findings revealed that LW-1 failed to induce antivirus infection activity and increase SA content in NahG tobacco, indicating the crucial role of SA in these processes. Meanwhile, LW-1 triggered defense-related early-signaling nitric oxide (NO) generation, as evidenced by the emergence of NO fluorescence in both types of tobacco upon treatment with LW-1, however, NO fluorescence was stronger in NahG compared to wild-type tobacco.

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Spent biomass from agricultural and forestry industries are substantial low-cost carbon source for reducing the input of microbial lipid production. Herein, the components of the vineyard winter prunings (VWPs) from 40 grape cultivars were analyzed. The VWPs contained (w/w) cellulose ranged from 24.

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Article Synopsis
  • Medium-chain fatty acid ethyl esters (MCFAEEs) play a key role in the aroma of wine and are produced during fermentation.
  • The study explored how oxidation-reduction potential (ORP) influences MCFAEE production using Saccharomyces cerevisiae in various ORP settings.
  • Results indicated that specific ORPs notably affect MCFAEE levels without impacting growth or sugar consumption, with the highest MCFAEE concentration achieved at 0 mV after 96 hours, enhancing the wine's aroma quality.
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β-Glucosidase is a key enzyme that hydrolyzes nonvolatile glycosylated precursors of aroma compounds and enhances the organoleptic quality of wines. In this study, a novel β-glucosidase from Hanseniaspora uvarum Yun268 was localized, purified, and characterized. Results indicated that β-glucosidase activity was mainly distributed within the cells.

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Background: Limonene is a widely used monoterpene in the production of food, pharmaceuticals, biofuels, etc. The objective of this work was to engineer Rhodosporidium toruloides as a cell factory for the production of limonene.

Results: By overexpressing the limonene synthase (LS), neryl pyrophosphate synthase (NPPS)/geranyl pyrophosphate synthase and the native hydroxy-methyl-glutaryl-CoA reductase (HMGR), we established a baseline for limonene production based on the mevalonate route in Rhodosporidium toruloides.

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Limonene and its derivatives have great market potential with diverse applications in food, pharmaceuticals, cosmetics, etc. Commercial production of limonene and its derivatives through extraction from plants suffers from the unstable market supply, while chemical synthesis of these compounds is hindered by high energy consumption and pollutant emission. Microbial biosynthesis provides a promising alternative approach for the sustainable supply of limonene and its derivatives.

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Article Synopsis
  • The study examined how adding nitrogen at different times affects wine ester production during fermentation with two types of yeast, Hanseniaspora uvarum and Saccharomyces cerevisiae.
  • Adding 50-200 mg/L of yeast assimilable nitrogen (YAN) at the start of fermentation had a minor impact on yeast competition and ester profiles.
  • However, supplementing nitrogen mid-fermentation greatly improved the survival of Hanseniaspora uvarum and led to increased levels of certain esters, with changes in carbon fluxes contributing to this enhanced production.
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The dynamic pattern of volatiles during Pinot Noir winemaking in monsoon climate with yeast extracellular extract (EE) treatment was analyzed. EE from selected Pichia fermentans and Rhodotorula mucilaginosa strains, and almond β-glucosidase were added after 12-h alcohol fermentation, and the volatiles were determined every 24 h by GC-MS. After 6-month storage, wine aroma was evaluated instrumentally as well as by well-trained panelists.

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The chemical profiles and aroma contribution of terpene compounds in Meili grapes and wine were analyzed. Bound terpene compounds were extracted using methanol, purified using Amberlite XAD-2 resin, concentrated in methanol/ethyl acetate, and enzymatically hydrolyzed to release aglycones. Free terpene compounds were identified using solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS).

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A novel analytical method was developed for the determination of organic acids (formic acid, acetic acid and propionic acid) in 1, 2-butylene oxide (1, 2-BO) products by valve switch-ion chromatography (IC).The samples were diluted in ethanol, and then were eluted from a concentrator column (IonPac TAC-ULP1) to an analytical column (IonPac AS11).The extracts were detected by a suppressed conductivity detector.

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Wine aroma response to a selected Hanseniaspora uvarum Yun268 strain was investigated using different inoculation strategies with commercial Saccharomyces cerevisiae yeast, namely, simultaneous fermentation (SiF), sequential fermentation (SeF), S. cerevisiae fermentation treated with extracellular extract of H. uvarum (EE), and pure S.

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Medium-chain fatty acid (MCFA) ethyl esters, as yeast secondary metabolites, significantly contribute to the fruity aroma of foods and beverages. To improve the MCFA ethyl ester content of wine, mixed fermentations with Hanseniaspora uvarum Yun268 and Saccharomyces cerevisiae were performed. Final volatiles were analyzed by gas solid phase microextraction-chromatography-mass spectrometry, and aroma characteristics were quantitated by sensory analysis.

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Microbial lipids produced by oleaginous yeasts serve as promising alternatives to traditional oils and fats for the production of biodiesel and oleochemicals. To improve its techno-economics, it is pivotal to use wastes and produce high quality lipids of special fatty acid composition. In the present study, four oleaginous yeasts were tested to use free fatty acids for lipid production under non-growth conditions.

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To reduce wastes and the costs of microbial lipid production, it is imperative to recycle resources, including spent cell mass, mineral nutrients and water. In the present study, lipid production by the oleaginous yeast Rhodosporidium toruloides was used as a model system to demonstrate resources recycling. It was found that the hydrolysates of spent cell mass were good media to support cell growth of various oleaginous yeasts.

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To evaluate the effectiveness of enzymatic assisted extraction (EAE) of lipid from the oleaginous yeast Rhodosporidium toruloides in the presence of beta-1,3-glucomannanase at a larger scale, we investigated the effects of enzymatic treatment and extraction conditions on lipid extraction yields at 10-L scale by using the broth of R. toruloides Y4 as the feed and ethyl acetate as the solvent. When it was treated for 0.

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With ever-increasing culture of yeasts for the production of biofuels and other metabolites, spent yeast cell mass exceeds its traditional market demands. Yeast cell mass contains glucose, mannose and other sugars that may be utilized for microbial culture. Here we demonstrated that the oleaginous yeast Lipomyces starkeyi could utilize glucose and mannose simultaneously for lipid production.

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Fatty acid ethyl esters (FAEEs) are attractive biofuel molecules. Conventional FAEEs production process uses triglycerides and ethanol as feedstocks and is sensitive to water contents. In this work, we show that the oleaginous yeast Rhodosporidium toruloides cells are capable of converting lipids into FAEEs intracellularly in aqueous phase.

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Microbial lipids are potential alternative feedstock for biofuel and oleochemical industries. The oleaginous yeast Rhodosporidium toruloides AS 2.1389 is an excellent lipid producer.

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Lignocellulosic biomass pretreatment with ionic liquids (ILs) has been emerged as a new technology, but the effects of residual ILs on the downstream biotransformation remain largely unknown. Here, three typical ILs were tested for their effects on lipid production by the oleaginous yeast Rhodosporidium toruloides AS 2.1389.

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Red yeasts hold great promise in the production of microbial lipids and carotenoids. Genetic study of red yeasts has attracted much attention; however, rapid amplification of genes from red yeast samples remains technically challenging. Here a highly efficient method for the preparation of genomic DNA (gDNA) template, which could be directly used for PCR, was developed.

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Triacylglycerols are among the most attractive alternative raw materials for biofuel development. Current oil plant-based technologies are limited in terms of triacylglycerol production capacity and rate. These limitations may be circumvented by biotransformation of carbohydrates into lipids; however, our understanding of microbial oleaginicity remains limited.

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The objective of this work is to investigate how dilution rate and carbon-to-nitrogen (C/N) ratio affects lipid accumulation by Rhodosporidium toruloides AS 2.138 9 in continuous culture. Under steady-state conditions, the increase in dilution rate led to the decrease in lipid content and lipid yield.

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Hydrolysates of lignocellulosic biomass contain glucose, xylose, arabinose, cellobiose, among other sugars. Effective utilization of these sugars remains challenging for microbial conversion, because most microorganisms consume such sugars sequentially with a strong preference for glucose. In the present study, the oleaginous yeast, Lipomyces starkeyi, was shown to consume cellobiose and xylose simultaneously and to produce intracellular lipids from cellobiose, xylose and glucose.

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Lipids produced by oleaginous microorganisms are a potential feedstock for biodiesel production and chemical synthesis. Yet, the costs of microbial lipids remain high, partially because the lipid recovery process is tedious and costly. In the present study, enzyme-assisted extraction of lipids from the culture of the yeast Rhodosporidium toruloides was carried out.

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Microbial production can be advantageous over the extraction of phytoterpenoids from natural plant sources, but it remains challenging to rationally and rapidly access efficient pathway variants. Previous engineering attempts mainly focused on the mevalonic acid (MVA) or methyl-d-erythritol phosphate (MEP) pathways responsible for the generation of precursors for terpenoids biosynthesis, and potential interactions between diterpenoids synthases were unexplored. Miltiradiene, the product of the stepwise conversion of (E,E,E)-geranylgeranyl diphosphate (GGPP) catalyzed by diterpene synthases SmCPS and SmKSL, has recently been identified as the precursor to tanshionones, a group of abietane-type norditerpenoids rich in the Chinese medicinal herb Salvia miltiorrhiza .

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