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Protein feed resources in China are scarce, which hinders the developement of feed industry and animal husbandry. Yeast protein is rich in nutrients and has significant development potential. Yeast strains were isolated and identified under acidic conditions (pH 3.5), from fermented flour, bovine rumen chyme, corn steep liquor, and other raw materials. Through the determination of the growth performance, bacterial protein and flavor of the strains, a promising high-protein yeast strain was identified as a potential strain for yeast protein processing. Further, the research indicated that 20 acid-tolerant yeast strains, including Saccharomyces cerevisiae, Pichia fermentans, Kluyveromyces marxianus, Yarrowia lipolytica, Candida tropicalis, Starmerella bacillaris, Zygosaccharomyces rouxii and Hanseniaspora thailandica, were obtained from different raw materials. Two superior strains, Pichia pastoris B-1 (7.65 g/L biomass, 4.96 g/L protein yield at pH 3.5; 9.32 g/L biomass, 5.81 g/L protein yield at pH 7.0) and Lactobacillus cerevisiae D-1 (8.00 g/L biomass, 3.91 g/L protein yield at pH 3.5; 14.91 g/L biomass, 6.87 g/L protein yield at pH 7.0), were identified based on biomass and protein production under shaking flask culture conditions. Flavor analysis revealed that strain B-1 had a higher content of flavor nucleotides and glutamic acid than strain D-1, along with a greater concentration of ester compounds. Thus, strain B-1 was identified as the potential strain for further application.. Therefore, B-1 strain was determined as the target strain. Finally, the growth characteristics and stress tolerance of B-1 strain were examined. It exhibited robust growth under conditions of pH≥2.0, temperature≤40 ℃ and NaCl concentration ( w /v )≤70 g/L.

Microorganisms are often affected by various environmental stresses (such as acid, heat, salt and oxidation) in the production and processing of fermented foods. Cross-protection refers to the phenomenon in which microorganisms are induced to increase stress tolerance after subjected to certain stresses. Improving microbial environmental tolerance with cross-protection is of great significance for improving the functional characteristics of microorganisms and promoting the development of the fermented food industry. In this paper, the cross-protection of microorganisms in fermented foods is reviewed. Furthermore, the response mechanisms of microbial cells under cross-protection are summarizes from the aspects of the cell wall and membrane barrier system, the intracellular pH regulation system, and the protein and amino acid regulation system, and possible strategies are suggested to improve the stability of microorganisms under stress conditions.

Leymus chinensis is a rhizomatous plant with extensive ecological adaptability and high economic value. It is one of the important constructive species in the eastern Eurasian steppe region, and is also an important high-quality pasture for animal husbandry in my country. Therefore, research on the biological and ecological characteristics of L. chinensis not only plays an important role in the basic theory of ecology, but also has important significance for the restoration of grassland ecology and animal husbandry production practice. This paper reviews the origin and distribution of L. chinensis, the research on low temperature resistance, drought resistance, salinity resistance, and grazing resistance of L. chinensis, the research on the ecotype of L. chinensis and the genetic diversity of L. chinensis. At the same time, the origin, diffusion, evolution research of L. chinensis, molecular mechanism of L. chinensis stress resistance and genetic diversity of L. chinensis are prospected. The purpose is to provide literature and data for scholars to deeply understand and master the biological and ecological characteristics of L. chinensis, and to provide reference for further in-depth research. [ABSTRACT FROM AUTHOR]

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Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】The variation patterns of agronomic traits and comprehensive performance of stress resistance of wheat lines were analyzed in regional test of Longdong, Gansu province in recent years, to provide reference for breed improvement in dryland wheat of Longdong region.【Method】192 winter wheat lines (without control) were used in the Longdong dryland wheat regional test in 2005-2022, and major agronomic traits, such as yield, growth period, basic seedling, total stem number, number of effective spike, plant height, spike length, grain number per spike, and thousand kernel weight were comprehensively analyzed by correlation analysis, multiple regression analysis, path analysis and cluster analysis, in addition, the tested lines were evaluated for stress tolerance (cold resistance, drought tolerance, lodging resistance, stripe rust, leaf rust, powdery mildew).【Result】The results showed that the yield of tested lines was 2791.65-5979.29 kg/hm², with an average of 4635.75 kg/hm². The coefficient of variation of main agronomic traits was as follows: yield (17.16%) ＞ number of effective spike (14.40%) ＞ plant height (11.37%) ＞ grain number per spike (9.65%) ＞ thousand kernel weight (9.54%)＞ spike length (9.47%) ＞ total stem number (8.55%) ＞ basic seedling (8.08%) ＞ growth period (1.21%); Yield, number of effective spike, grain number per spike, thousand kernel weight and plant height increased slowly with the advance of the year, while the growth period decreased slowly. The results of correlation analysis indicated that yield was significantly and positively correlated with the grain number per spike (r=0.645), thousand kernel weight (r=0.594) and plant height (r=0.475), and a highly significant positive correlation was found between number of effective spike and grain number per spike (r=0.729). Multiple regression analysis revealed that spike length, grain number per spike and thousand kernel weight determined 66% of the variance in yield. The results of the pathway analysis demonstrated that the direct (P=0.485) and comprehensive contribution (P=0.615) of thousand kernel weight were the largest, followed by the grain number per spike (P=0.471,P=0.543), and the direct (P=0.326) and comprehensive contribution (P=0.268) of spike length were the smallest. Cluster analysis divided the tested wheat lines into 5 categories, which the lines in the first group had high yield and thousand kernel weight, and the rest of the agronomic traits were more coordinated, accounting for 7.29%,making them ideal materials for selecting and breeding excellent lines (varieties). Stress resistance analysis showed that more than 66% of the tested lines had strong cold resistance, drought resistance and lodging resistance. Meanwhile, more than 55% of the tested lines were immune or highly resistant to stripe rust, leaf rust and powdery mildew.【Conclusion】The overall yield level of the tested lines is relatively low and unstable, and the yield and number of effective spike are greatly affected by the environment. Grain number per spike and thousand kernel weight are the main factors affecting the yield of dryland wheat in Longdong, and the yield can be improved by increasing grain number per spike and thousand kernel weight at the same time. Moreover, varieties with high yield and wide adaptability should have strong comprehensive resistance to cold, drought and disease. [ABSTRACT FROM AUTHOR]

Compared with other five traditional hormones, the identification of melatonin(MT)was done in only two decades. MT is an emerging plant hormone, which is a pleiotropic signaling molecule with multiple physiological functions in organisms. In plants, MT is called phytomelatonin, which is not only involved in the regulation of seed germination, root system architecture, stomatal movement, biological rhythm, flowering, and senescence, but also in the response of plants to biotic and abiotic stresses by activating the activities of antioxidant system, scavenging ROS, followed by reducing osmotic stress, oxidative stress, protein denaturation, and cell damage caused by biotic and abiotic stress, thus plants respond to biotic and abiotic stresses. Based on the latest research progress of MT metabolism in plant and its response to abiotic stress, the anabolism and catabolism of MT in plants are summarized. The plant resistance to high temperature, low temperature, drought, salt, heavy metals, ultraviolet radiation and waterlogging is improved ultimately under stress by MT directly removing ROS and/or triggering the signal transduction pathway, up‑regulating resistance related gene expression, and then activating the vitality of osmoregulation system and antioxidant system, promoting the synthesis of stress protein and secondary metabolic substances, stable photosynthesis and carbon metabolism, and thus reducing the accumulation of ROS and cell oxidative damage. This paper lays the theoretical foundation for understanding the metabolism, physiological function, and cellular signal transduction of MT in plants, and point out the future research directions. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lignocellulosic biomass（LCB）is a promising alternative to fossil material, the biofuels, biochemicals and biomaterials are produced via its biorefinery, which may reduce carbon emissions, contributing to achieve the carbon peaking and carbon neutrality goals. Therefore, LCB is receiving more and more attentions. However, there are multiple steps involved in lignocellulosic biorefinery including pretreatment, microbial fermentation and product purification, in which, various compounds generated from pretreatment of LCB inhibit cell growth and fermentation performance of microbes, which is one of the bottlenecks of bioconversion efficiency. Escherichia coli is a commonly used host for lignocellulosic biorefinery and extensively used for the production of many compounds, thus, it is of great importance to study the stress tolerance of E. coli to inhibitors in lignocellulosic hydrolysates for improving lignocellulosic biorefinery efficiency. This paper first introduced the main components and structures of lignocellulose, and briefly elucidated pretreatment methods to lignocellulose as well as main inhibitors in the hydrolysate after pretreatment. Then the paper summarized the toxic effects of main inhibitor furans, carboxylic acids and phenolics in the hydrolysate of lignocellulose on E. coli, as well as the mechanisms of stress tolerance against these inhibitors and the engineering targets for improving strain tolerance based on the mechanisms. Finally, the paper reviewed the strategies for strain engineering to improve the tolerance of E. coli to above motioned inhibitors, including random mutagenesis, adaptive laboratory evolution and omics-assisted rational design,, aiming to provide references for metabolic engineering of efficient E. coli strains for lignocellulosic biorefinery. [ABSTRACT FROM AUTHOR]

Microbial cell factories have been extensively used for sustainable production of biofuels, as well as high value and bulk chemicals. However, high concentration products or substrates, as well as stressful conditions during industrial production, may compromise fermentation efficiency and decreasing economics of production. In this context, microbial stress tolerance is crucial for green and sustainable production of the target products. In recent years, the use of transporters to protect microbial cells from toxic compounds for enhancing strain tolerance has received increasing worldwide attention. This review summarizes the progress of studies on microbial strain tolerance enhancement based on transporter engineering, analyses the current key points in the field of transporter research and discusses strategies to enhance strain tolerance based on transporter manipulation. Especially，the review highlights the applications of artificial intelligence in transporter annotation, structure simulation and substrate-transporter interaction prediction, aiming to promote the application of microorganisms in biological manufacturing. [ABSTRACT FROM AUTHOR]

Cellulosic ethanol, as a clean and renewable green energy, has promising application prospects. However, the fermentation process of Saccharomyces cerevisiae using lignocellulose to produce ethanol is susceptible to various stresses，thus improving the stress tolerance of fermenting microorganisms has become an essential topic in the field of biorefinery. In this work, we attempted to engineer cells to use the output of the internal redox-sensitive biosensor Yap1 to drive intracellular metabolic reactions（including ROS metabolism and aldehyde degradation）, which will improve the tolerance of S. cerevisiae to reactive oxygen species and aldehyde inhibitors. Firstly, we analyzed the sequences of several native endogenous promoters（PTRR1, PTRX2, and PMET16）in S. cerevisiae that can be regulated by the redox-sensitive biosensor Yapl and their response strengths to typical inhibitors in lignocellulosic hydrolysates. Secondly, we designed redox-sensitive genetic parts in order to improve the stress resistance of S. cerevisiae by combining the promoters with corresponding resistance genes. Finally, we tried to integrate the better performing GP-CTT and GP-ADH in tandem to construct a dual-genetic parts system, which was named GP-AC. The integration greatly improved the ability of S. cerevisiae to cope with multiple complex stresses, and the cell death rate decreased by 69.6% under the coexistence of aldehyde and oxidation stress. Compared with GP-CTT, the specific growth rate, glucose consumption rate and ethanol production rate of GP-AC increased by 64.2%, 60.1%, and 58.9%, respectively. At the same time, the catalase activity of the recombinant strain increased by 40.2% compared with the single genetic part. In conclusion, this study systematically improved the stress tolerance of S. cerevisiae by rationally designing the genetic circuit of redox-sensitive genetic parts and strengthening the intracellular vital antioxidant enzymes and aldehyde degradation pathways. It provides new insights for rationally designing and constructing feedback genetic circuits to dynamically improve yeast robustness. [ABSTRACT FROM AUTHOR]

This work aims to construct Saccharomyces cerevisiae strains with excellent high-temperature tolerance and investigate the high-temperature tolerance mechanisms of the strains. CRISPR/Cas9 technology was used to knock out ASP3 in flocculating industrial S. cerevisiae strain KF-7 and further highly expressed CRZ1 (Encoding transcription factor Crz1p with zinc finger structure). And the high-temperature tolerance mechanism of the recombinant strains was revealed through comparative transcriptomic analysis. The results showed that the ASP3-knockout strain KAS11 utilized 98.36 g/L glucose and produced 43.68 g/L ethanol at 44℃ . After CRZ1 high expression based on KAS11, strain KASCR7 produced 48.02 g/L ethanol from 105.37 g/L glucose. Compared with KF-7, the ethanol production of the two recombinant strains increased by 4.77% and 15.18%, respectively. Comparative transcriptomic analysis revealed that genes involved in ribosome biogenesis and translation significantly repressed in the recombinant strains under high-temperature stress. In contrast, heat shock protein genes as well as genes involved in biosynthesis of NAD+, NADH, purine, glycerol, and proline were significantly induced. These responses may collectively lead to the enhanced high-temperature tolerance of the recombinant strains. The results may provide excellent strain resources and theoretical basis for the construction of excellent high-temperature tolerant S. cerevisiae strains. [ABSTRACT FROM AUTHOR]

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of South China Agricultural University is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The growth and physiological changes of poinsettia (Euphorbia pulcherrima Willd.) were observed, which gave a discussion on the potential of phytoremediation using poinsettia and provided a new idea for the treatment of Zn-contaminated soils. [Method] Poinsettia cutting seedlings were used as experimental materials, and the pot experiment was carried out by incomplete randomized block design.The treatments with six Zn-pollution concentrations in soils were set: CK (0 mg/kg, without adding Zn reagent), T1 (200 mg/kg), T2 (300 mg/kg), T3 (500 mg/kg), T4 (800 mg/kg) and T5 (1000 mg/kg) (dry mass), respectively, repeated four times.Plant height and ground diameter of poinsettia were measured every 14 days during the experiment.The biomass, root morphology index (root length, total projection area, root surface area, average diameter, root volume, and root tip number), leaf number, leaf area, chlorophyll content, malondialdehyde (MDA) content, and the accumulation content, tolerance index (TI), and transport factor (TF) of poinsettia for Zn were analyzed after 112 days of sampling. [Result] (ⅰ) Compared with the control group, the plant height increment, ground diameter increment, biomass, and root volume, the leaf number, leaf area, and chlorophyll content of poinsettia were inhibited to varying degrees, but no obvious symptoms of heavy metal toxicity were observed. (ⅱ) Poinsettia had strong resistance to Zn, which was shown in that TI was more than 50%, which showed a certain ‘hormesis’ phenomenon with the increase of Zn concentration in soil; The MDA content increased under high Zn concentration; The change of relative conductivity of leaves was not significant. (ⅲ) The Zn content in different parts of the poinsettia plant was positively correlated with Zn concentration in soil, and the accumulation capacity of different tissues for Zn was roots ＞ leaves ＞ stems.Under all treatments, the Zn content in the aboveground parts of poinsettia was significantly higher than that in the roots.Except for the T1 treatment (0.96), the TF of the other treatments was ＞ 1, which was suitable for phytoextraction. [Conclusion] Poinsettia has a certain tolerance to Zn.When Zn concentration in soil is 1000 mg/kg, the accumulation and migration (from roots to the aboveground parts) ability of poinsettia for Zn are strong, which makes poinsettia suitable for phytoextraction.As an ornamental plant, poinsettia can also beautify the environment while phytoremediation is carried out in heavy-metals contaminated areas. [ABSTRACT FROM AUTHOR]

The abuse of pesticides and chemical fertilizers poses a great threat to human health and living environment. It is very necessary to develop new fertilizers that can reduce the amount of chemical fertilizers and meet the sustainable development of agricul-ture. Trichoderma as a conunon functional microorganism of new fertilizer, has a wide range of applications in the field of agriculture. Among many mechanisms of promoting growth and disease prevention, it is an important way for Trichoderma to promote plant growth by producing indole-3-actsic acid ( IAA ). In order to further enhance the growth promoting effect and disease resistance of Trichoderma wide, the TvTRPS gene encoding tryptophan synthase (TRPS) and the TvTDC gene encoding L-tryptophan decarboxylase (TDC) were identified and cloned in Trichoderma viride Tv-1511, constructed the engineering strain of Trichoderma viride ovenspressing TvTRPS and TvTDC, and evaluated their effects on stress tolerance, IAA pnaluetion and plant growth promotion. The results show that Tri-choderma viride engineering strains overezpressing TvTRPS and TvTDC have the improved ability to synthesize IAA, as well as have stronger stress tolerance and growth promotion ability, which lays a foundation for the further application of Trichoderma viride in agri-cultural production. [ABSTRACT FROM AUTHOR]

In order to explore an environmental removal method of grain mycotoxins and to overcome the problem of poor stability of biodegradation method, the Tibetan yeast strains were selected as the research object, and the strains with better degradation effects on zearalenone (ZEN) were screened to explore the functions and mechanisms in this study.The results showed that Tibet Rhodotorula mucilaginosa had a good degradation effect on ZEN, and the degradation effect gradually improved with the increase of the bacterial concentration.Through the evaluation of the toxin removal effect of different yeast treatment solutions, it was found that the removal mechanism of the yeast on ZEN was mainly adsorption, accompanied by a certain degree of intracellular biodegradation.The degradation products of ZEN were determined by liquid chromatography-mass spectrometry.It was found that the degradation products may be zearalenol and zearalenone, and the safety of the degradation products needed further verification.The stress tolerance test of Tibet R.mucilaginosa showed that it had a certain tolerance to low temperature and oxidative stress.

Calcium-dependent protein kinases (CDPKs/CPKs) are members of the Ca 2+ -sensitive Ser/Thr protein kinase family and play a crucial role in plant growth and development and responses to abiotic stress. CDPKs are capable of rapidly sensing changes in intracellular Ca 2+ signals and recognizing and phosphorylating specific substrates, thereby transmitting and amplifying Ca 2+ signal cascades downstream. They are involved in plant responses to stress conditions such as drought, saline-alkali stress, and injuries and regulate plant growth and development, gene expression, ion channel activity, and stomatal movement. The autophosphorylation of CDPKs can affect their activities and substrate specificity. CDPKs have the ability to bind to and phosphorylate multiple substrates. In addition to participating in respiratory burst oxidase homolog (RBOH), mitogen-activated protein kinase (MAPK), and plant hormone signaling pathways, CDPKs can also bind to 14-3-3 proteins, which enables the regulation of plant responses to stress and promotes plant growth and development. This paper summarized the research findings on the discovery, structure, classification, and roles of CDPKs in plant responses to stress and proposed the future research directions, aiming to provide the genetic resources and a theoretical basis for improving the stress tolerance of crops.

Objective To study the changes of acid resistance, oxidation resistance and high osmotic pressure resis⁃ tance of Streptococcus mutans after knockout of rnc gene and its possible regulatory mechanism. Methods Through PCR ligation mutagenesis, an rnc knockout mutant (Smurnc) was constructed. Acid tolerance, oxidation tolerance and high osmotic pressure tolerance were compared between Smurnc and the wild strain respectively. Real⁃time RT⁃PCR was used to verify the changes in expression of stress tolerance related genes at the transcriptional level. Results When rnc gene was knocked out, the acid tolerance (c2=13.464, P=0.001) and oxidation tolerance (c2=4.505, P=0.048) of Streptococcus mutans was significantly decreased, but the high osmotic pressure tolerance was significantly increased (c2=11.971, P=0.001). Expression of stress tolerance related genes luxS and ropA (0.64 and 0.51 times expression of the wild strain) had been significantly downregulated (P

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Dehydration-responsive element binding proteins (DREBs) are an important class of transcription factors related to plant stress tolerance. Ammopiptanthus mongolicus is an evergreen broadleaf shrub endemic to desert areas of northwest China, and it has a very high tolerance to harsh environments. In order to reveal the functions and mechanisms of the AmDREB1F gene from this species in enduring abiotic stresses, we performed subcellular localization test, expression pattern analysis, and stress tolerance evaluation of transgenic Arabidopsis harboring this gene. The protein encoded by AmDREB1F was localized in the nucleus. In laboratory-cultured A. mongolicus seedlings, the expression of AmDREB1F was induced significantly by cold and drought but very slightly by salt and heat stresses, and undetectable upon ABA treatment. In leaves of naturally growing shrubs in the wild, the expression levels of the AmDREB1F gene were much higher during the late autumn, winter and early spring than in other seasons. Moreover, the expression was abundant in roots and immature pods rather than other organs of the shrubs. Constitutive expression of AmDREB1F in Arabidopsis induced the expression of several DREB-regulated stress-responsive genes and improved the tolerance of transgenic lines to drought, high salinity and low temperature as well as oxidative stress. The constitutive expression also caused growth retardation of the transgenics, which could be eliminated by the application of gibberellin 3. Stress-inducible expression of AmDREB1F also enhanced the tolerance of transgenic Arabidopsis to all of the four stresses mentioned above, without affecting its growth and development. These results suggest that AmDREB1F gene may play positive regulatory roles in response to abiotic stresses through the ABA-independent signaling pathways.