187 results about "Sugar acids" patented technology

The invention relates to the technical field of quality detection and grading, in particular to a citrus internal and external quality detection and grading method and system based on deep learning. The method comprises the following steps: carrying out spectral image acquisition on oranges to obtain spectral characteristic wave band data; performing tactile perception data acquisition on the citrus to obtain citrus tactile perception data; according to the spectral characteristic wave band data, sugar-acid ratio gradient identification of different areas of the citrus is carried out, internal maturity grade division of the different areas of the citrus is carried out, and internal maturity grade data of the citrus is obtained; performing external form perception analysis of different maturity areas on the citrus internal maturity grade data to obtain citrus external form perception data; performing citrus internal and external quality memory learning on the citrus external form perception data and the citrus internal maturity grade data to obtain citrus internal and external quality memory normalized data; according to the method, the quality detection and grading technology is optimized, so that the quality detection and grading technology is more perfect.

The invention relates to the technical field of microbial metabolism engineering, in particular to a construction method and application of genetically engineered bacteria for efficiently producing O-acetyl-L-homoserine. The construction method specifically comprises the following steps: (1) taking a strain Escherichia coli W3110 as a chassis, and knocking out a homoserine O-succinyl transferase coding gene metA; (2) knocking out a gamma-cystathionine synthetase encoding gene metB; (3) knocking out a cysteine lyase coding gene metC; (4) carrying out weakening expression on an O-acetyl-L-homoserine thiolase coding gene metYcm from the marine cyclobacterium; (5) overexpressing a ribulose diphosphate carboxylase coding gene rbcLSse from the synechococcus elongate; (6) overexpressing a ribulose phosphate kinase coding gene prkse from the synechococcus slender; and (7) weakening the expression of the citrate synthase coding gene gltA to obtain the genetically engineered bacterium for efficiently producing the O-acetyl-L-homoserine. The strain provided by the invention is used for producing O-acetyl-L-homoserine, and has the advantages of high yield, high yield and high sugar-acid conversion rate.

The invention discloses construction and application of a plasmid-free and auxotrophy-free L-tryptophan production strain, and belongs to the technical field of bioengineering. According to the invention, a plurality of key anti-feedback inhibition enzymes in a tryptophan synthesis route are optimized and combined, and the optimal combination is integrated into an escherichia coli genome by utilizing a CRISPR (clustered regularly interspaced short palindromic repeats)-ASPR (clustered regularly interspaced short palindromic repeats)-trans-spansses (clustered regularly interspaced short palindromic repeats) system. According to the invention, the plasmid-free and nutritional deficiency-free engineering strain ZH-3 for producing the L-tryptophan is successfully constructed, and under the conditions of no use of antibiotics, use of inducers and no addition of additional substances, the total yield of the L-tryptophan reaches 43g / L and the sugar-acid conversion rate is increased to 0.180 g / g after the strain is cultured for 35h in a 3L fermentation tank. The strategy used by the invention is not only suitable for construction of tryptophan genome integration expression strains, but also provides reference for construction of other plasmid-free amino acid production strains.

The invention provides a genetically engineered bacterium for producing O-succinyl-L-homoserine as well as a construction method and application of the genetically engineered bacterium. In a chassis bacterium genome, the expression of a 2-ketoglutaric acid decarboxylase encoding gene sucA is enhanced, and the expression of a succinyl-coenzyme A synthetase encoding gene sucD is weakened, so that the supply of succinyl-coenzyme A is increased; the method comprises the following steps: increasing the NADPH (Nicotinamide Adenine Dinucleotide Phosphate) reducing capacity and ATP (Adenosine Triphosphate) energy supply of a chassis bacterium, increasing DNA (Deoxyribose Nucleic Acid) in combination with a transcription dual regulatory factor ompR to improve the stress resistance of escherichia coli under high osmotic pressure, and introducing an overexpression plasmid containing a homoserine transsuccinylase coding gene metA to construct the genetically engineered bacterium for producing O-succinyl-L-homoserine. The engineering strain obtained through a systematic metabolic engineering modification strategy can realize effective accumulation of OSH, the shake flask yield of OSH reaches 19.8 g / L, the fed-batch fermentation yield of a 5L fermentation tank reaches 110.5 g / L, the sugar-acid conversion rate reaches 52.6%, and a foundation is laid for subsequent construction of high-yield OSH engineering bacteria.

The invention relates to the technical field of grapes, in particular to application of chlorogenic acid to improvement of grape fruit quality, and the dosage of the chlorogenic acid is 50-200M in mass concentration. The use method comprises the following steps: preparing the chlorogenic acid into a chlorogenic acid aqueous solution, and spraying the chlorogenic acid aqueous solution in a grape fruit swelling period or a grape fruit swelling later period once every 7-12 days for 3-6 times. By applying chlorogenic acid, the anthocyanin content of the grape fruits is remarkably increased, and the coloring effect of the grape fruits can be remarkably improved. By applying the chlorogenic acid externally, the fruit weight, the soluble solid content, the soluble total sugar content and the sugar-acid ratio of the grape fruits are increased, the titratable acid content is reduced, and the flavor and the nutrient content of the grape fruits are improved. The invention promotes the application and development of the chlorogenic acid in the maturation and quality of the grape fruits before harvesting, and solves the problems that the fruit ripening agent in the current market contains hormones and is high in price, the grapes are poor in coloring and slow in color turning, and the potential toxicity exists.

The invention discloses a spermidine synthetase mutant and application of the spermidine synthetase mutant in synthesis of spermidine, and belongs to the technical field of genetic engineering and metabolic engineering. According to the method, the spermidine synthetase is mutated firstly, the efficiency of the spermidine synthetase is improved, and on the basis, the dissolved oxygen and fed-batch concentration are optimally controlled through fermentation, so that the yield of spermidine is improved. The corynebacterium glutamicum provided by the invention is an engineering bacterium with plasmids and without defects, and after the corynebacterium glutamicum is subjected to fed-batch fermentation in a 5L fermentation tank for 68 hours, the yield of spermidine reaches 25.1 g / L, and the sugar-acid conversion rate is 17.9%.

The invention belongs to the technical field of biology, and particularly relates to a method for producing xylitol through two-step enzyme catalysis of hemicellulose hydrolysate, and the method comprises the following steps: taking hemicellulose hydrolysate as a raw material, adding arabinose dehydrogenase, NADH oxidase and coenzyme NADH, and carrying out first-step fermentation until no L-arabinose residue exists in fermentation liquor to obtain fermentation reaction liquor I; and adding xylose reductase and glucose dehydrogenase into the fermentation reaction liquid I, and carrying out second-step fermentation to obtain a fermentation product containing xylitol. According to the two-step enzyme catalysis method provided by the invention, xylitol is prepared, and high-purity xylose does not need to be used as a raw material; according to the present invention, the cheap hemicellulose hydrolysate can be directly adopted as the raw material, the xylose conversion rate and the xylitol yield can exceed 99%, the impurity arabitol content in the product is low, the other impurity saccharic acid is easy to separate, and the problems of complex process, large separation difficulty and high cost in the xylitol refining process are successfully solved.

The embodiment of the invention provides a fermentation method of L-leucine and L-isoleucine. According to the method, at least one L-leucine or L-isoleucine producing strain is used for fermentation culture; according to the method, relatively cheap molasses with rich carbon and nitrogen sources is selected as materials, corn steep liquor with more impurities is abandoned, and the molasses is converted into a nutrient substance containing more carbon and nitrogen sources capable of being utilized by strains through enzymolysis; in addition, in order to control the ratio of carbon and nitrogen sources in the fermentation liquor, a more accurate material supplementing process is selected, so that the fermentation requirements of strains can be guaranteed, and the situation that the liquid nitrogen source of the fermentation liquor is too high and too low can be effectively avoided, and the purposes of increasing the yield and the sugar acid conversion rate and reducing heteroacid byproducts are achieved.

The present invention provides a method for increasing the fermentation yield of L-lysine, and belongs to the field of L-amino acid fermentation. The method for increasing the fermentation yield of L-lysine is composed of the following steps: preparing a shake flask culture solution, preparing a seed solution, and fermenting and culturing. The method for increasing the fermentation yield of L-lysine of the present invention can effectively improve the tolerance of the bacterial body to high osmotic pressure, improve the acid production performance in the late fermentation period, and improve the single-tank yield and sugar-acid conversion rate of L-lysine; at the same time, further reduce the adverse effects of osmotic pressure regulators on the fermentation stability of L-lysine, and effectively avoid the problem of excessive addition of osmotic pressure regulators inhibiting bacterial metabolism, extending the fermentation production cycle, and reducing fermentation efficiency.

The invention provides an L-tryptophan production strain as well as a construction method and application thereof. The strain lacks tnaA, serA, trpR and trpL genes; the transcription of aroC and tktA genes is enhanced by using a tac promoter, and the aroC and tktA genes are respectively integrated to tnaA and trpR sites; according to the present invention, the trpE gene in the genome is subjected to site-directed mutagenesis solution feedback, the tryptophan feedback inhibition is relieved, the constructed strain has advantages of good tryptophan synthesis ability, stable performance and high acid production efficiency, especially by carrying the medium copy plasmid pTtas, the finally obtained L-tryptophan production strain has the clear genetic background, the plasmid pTtas carried by the strain has the antibiotic-free screening tag, and the obtained L-tryptophan production strain has the broad application prospect. The strain is high in yield, free of antibiotic pressure screening, good in L-tryptophan production performance and high in sugar-acid conversion rate, and L-tryptophan can be stably and efficiently produced or accumulated through a microorganism direct fermentation method.

An engineered bacterium for improving tryptophan yield, a construction method therefor, and a use thereof. A strain capable of tolerating a high concentration of tryptophan was obtained by screening. Genome sequencing and protein sequence analysis of the strain revealed that some proteins in the strain had undergone point mutations, and these mutants can improve the tryptophan yield. In order to further improve the tryptophan yield, modifications are made to a protein sequence expressed by a fadR gene or a protein sequence expressed by a pepD gene in a starting bacterium. Such modifications enable the obtained engineered bacterium to have a higher tryptophan yield than the starting bacterium. In the case of large-scale production, in a 5 L fermentation tank, the tryptophan yield can reach 62.38±5.80 g / L, and the sugar-to-acid conversion rate can reach 24.1%. Compared with the original bacterium, the tryptophan yield is increased by 1.48 folds, and the sugar-to-acid conversion rate is increased by 1.26 folds. The biological material and the use thereof relate to the technical field of molecular biology and have wide practical application value.

The invention discloses a method for improving the synthesis level of L-tryptophan in escherichia coli based on ARTP mutagenesis high-throughput screening, and belongs to the technical field of bioengineering. According to the invention, the L-tryptophan biosensor pSensor-trp3 is constructed, and the L-tryptophan biosensor pSensor-trp3 is good in response under the condition that the exogenous addition concentration range of L-tryptophan is 0-300mg. L <-1 >. High-throughput screening is performed by using a flow cytometry, a dominant mutant strain YB-2 is obtained through iterative mutagenesis, and the shake flask L-tryptophan yield and the sugar-acid conversion rate of the dominant mutant strain YB-2 are 5.68 g.L <-1 > and 0.103 g.g <-1 > respectively and are increased by 11.4% and 10.7%. Through second-generation whole genome re-sequencing comparative analysis, it is speculated that the genes ynfB and waaO possibly have a promoting effect on synthesis of L-tryptophan. The L-tryptophan biosensor used in the invention also provides reference for high-throughput screening and transformation of other related L-tryptophan production strains.

The invention relates to the technical field of tomato juice processing, in particular to flavor-improved NFC tomato juice, a preparation method thereof and compound juice. The invention provides flavor-enhanced NFC tomato juice, a preparation method thereof and composite fruit juice. The tomato NFC beverage prepared by the preparation method is bright in color, mellow and fine in taste, appropriate in sugar-acid ratio, moderate in viscosity and weakened in layering phenomenon by utilizing specific ultrasonic treatment and ultrahigh-pressure non-thermal sterilization processes, and the flavor of tomato raw materials and the flavor of tomato juice, especially the characteristic flavor of tomatoes, are enhanced under the condition of no additives. In addition, various nutrient substances in the tomatoes are reserved to the maximum extent, and the special color, flavor and nutrient components of the product are still kept in the storage period.

The invention discloses a production strain for fermenting L-histidine and application of the production strain, and belongs to the technical field of biological engineering. According to the invention, escherichia coli E.coli CICC 10243 is taken as an original strain, histidine synthesis operon genes hisDCB-cg2302-cg2301-HA-impA-FI, hisN and hisEG from corynebacterium glutamicum are integrated on a genome of the escherichia coli E.coli CICC 10243, a pyruvate dehydrogenase AceE mutant coding gene is introduced, and an escherichia coli transcription factor SlyA coding gene slyA is inactivated. The novel strain E.coli His08 for fermentation production of L-histidine is prepared and fermented in a 5L fermentation tank for 60 h, the histidine yield reaches 58.39 g / L, the sugar-acid conversion rate is 0.15 g / g, and the strain E.coli His08 has important application value.

The present invention provides a method for improving the ability of Escherichia coli to produce O-succinyl-L-homoserine by using adaptive evolution. The method uses Escherichia coli lacking cystathionine-γ-synthase and homoserine kinase and relieving feedback repression as a starting strain, and uses a culture medium containing different O-succinyl-L-homoserine concentrations to perform test tube passage pressure screening on the strain under aerobic conditions, and in this way, adaptive evolution is performed to obtain Escherichia coli with good growth performance and high yield of O-succinyl-L-homoserine. The present invention improves the substrate utilization rate and product tolerance of the strain by using adaptive evolution under aerobic conditions, thereby improving the ability of the strain to produce O-succinyl-L-homoserine and the sugar-acid conversion rate.

Escherichia coli is modified by means of metabolic engineering, a genetically engineered bacterium for high yield of O-succinyl-L-homoserine is obtained, and a construction method of the genetically engineered bacterium comprises the following steps: weakening a synthetic route of an organic acid metabolic byproduct of a chassis strain E.coli W3110 [delta] metI [delta] metJ [delta] thrB [delta] metB; wherein the synthetic route of the organic acid metabolic byproducts is selected from at least one of a formic acid synthetic route, a lactic acid synthetic route and an ethanol synthetic route. The constructed genetically engineered bacterium is applied to microbial fermentation production of the O-succinyl-L-homoserine, effective accumulation of the O-succinyl-L-homoserine is achieved, the sugar acid conversion rate reaches 46.8%, and a foundation is laid for subsequent construction of high-yield O-succinyl-L-homoserine engineering bacteria.

The invention is suitable for the technical field of chemical synthesis, and provides a nitrogen modified metal composite material and a preparation method and application thereof. According to the method, primary biomass and derivatives thereof are carbonized in ethylene glycol containing a nitrogen precursor, meanwhile, bimetal is reduced and loaded on a nitrogen modified functional carbon carrier, so that an alloy catalytic site is formed, and the alloy catalytic site is beneficial to adsorption of monosaccharide, promotion of mass transfer of substances and promotion of monosaccharide oxidation into a final product saccharic acid; therefore, the monosaccharide oxidation reaction is efficiently carried out, and a theoretical basis is provided for directly synthesizing saccharic acid from agricultural wastes such as straw through chemical catalytic oxidation. The monosaccharide comprises xylose, glucose and the like; the product saccharic acid comprises xylonic acid, gluconic acid, glucaric acid and the like. Results show that the conversion rate of glucose is 100%, the yield of gluconic acid is 81.7%, and the yield of glucaric acid is 13.1%.

The invention discloses a fermentation production process for improving the conversion rate of L-arginine and a strain used by the fermentation production process, and belongs to the technical field of fermentation engineering. According to the method, the content of residual sugar and ammonia nitrogen in the fermentation process of the L-arginine is accurately regulated and controlled, so that the growth speed of thalli and the sugar-acid conversion capacity are controlled, the fermentation period is shortened, meanwhile, the fermentation period of the L-arginine is 44-55 hours, the produced acid reaches 130 g / L or above, and the conversion rate is 50% or above by supplementing materials in the fermentation process and controlling other processes. According to the process, the acid production and conversion rate of the strain are greatly improved, and the production cost is reduced.

The invention discloses an agricultural product quality detection method, and relates to the technical field of agricultural product quality detection.The method includes the steps of S1, tomato treatment, S2, tomato appearance quality detection and analysis, S3, tomato flavor quality detection and analysis, S4, tomato nutritional ingredient detection and analysis, S5, tomato pesticide residue detection and analysis, S6, tomato comprehensive quality analysis and S7, tomato storage. According to the method, the tomatoes in the batch are subjected to sampling detection according to the set proportion, the appearance quality of the tomatoes is evaluated from the three aspects of volume, hardness and color, the flavor quality of the tomatoes is evaluated from the two aspects of sugar-acid ratio and volatile aromatic substances, and the nutritional ingredients of the tomatoes are evaluated from the two aspects of soluble substances and pH values; finally, pesticide residues are detected, comprehensive quality analysis is conducted on the tomatoes in multiple aspects, and then a proper storage refrigeration house is screened out according to the comprehensive quality of the tomatoes.

The invention relates to a preparation process of a novel Danfit sparkling grape juice, and belongs to the technical field of grape juice preparation. Fully mature, brightly colored, non-rotten and pesticide-free Danfit grape fruits are selected, rinsed in clean water, dried and then the fruit stems are removed; the grapes are crushed after being quickly frozen at low temperature, and the pulp after low-temperature immersion is squeezed using a press to make all the juice flow out; the squeezed juice is first filtered with a filter screen, then put into a sterilized container, a clarifier is added, and naturally clarified at low temperature; the upper clarified liquid is taken and finely filtered through a modified microfiltration membrane; the sugar-acid ratio of the grape juice is adjusted and then homogenized, and then rapidly cooled after ultra-high temperature instantaneous sterilization; the sterilized grape juice is cooled and added to a soda mixer, filled with carbon dioxide, and then poured into a sterilized glass bottle, and sealed and packaged; the novel Danfit sparkling grape juice prepared by the invention contains a high level of proanthocyanidins.

The invention provides a high-yield O-succinyl-L-homoserine engineering bacterium as well as a construction method and application of the high-yield O-succinyl-L-homoserine engineering bacterium. According to the invention, O-succinyl-L-homoserine genetically engineered bacteria with high yield of O-succinyl-L-homoserine are constructed by introducing O-succinyl-homoserine transferase from Vibrio cholera into a chassis strain in an exogenous manner and obtaining a gene mutant metAVc (T242A) of the O-succinyl-L-homoserine transferase, and further increasing the expression of the O-succinyl-L-homoserine transferase by adopting a Trc promoter. The engineering strain obtained through a systematic metabolic engineering modification strategy can realize effective accumulation of OSH, the shake flask yield of OSH reaches 18.8 g / L, the fed-batch fermentation yield of a 5L fermentation tank reaches 105.4 g / L, the sugar-acid conversion rate reaches 52.6%, and a foundation is laid for subsequent construction of high-yield OSH engineering bacteria.

The invention discloses recombinant escherichia coli capable of increasing the yield of L-homoserine and a preparation method of the recombinant escherichia coli, and belongs to the technical field of biology. By constructing a multi-way glucose transport system, L-homoserine synthesis precursor supply is enhanced, high-energy-consumption genes are knocked out, ATP regeneration is enhanced, ATP availability is improved, an acetic acid conversion way is established, and an L-homoserine degradation way is blocked, so that a metabolic flow of a synthesis way is further enhanced; a pyruvate carboxylase mutant and a designed promoter are introduced to weaken expression of citrate synthase and reconstruct key metabolic nodes, and fed-batch fermentation conditions of the strain in a 5L bioreactor are optimized according to metabolic characteristics of the strain; the genetically engineered bacterium which is clear in genetic background, does not carry plasmids, does not need induction and can stably and efficiently produce the L-homoserine is obtained, the yield of the L-homoserine reaches 141.5 g / L after the L-homoserine is fermented for 56h in a 5L fermentation tank, the saccharic acid conversion rate reaches 40%, and the genetically engineered bacterium has a certain application prospect.

The invention belongs to the technical field of microorganisms, and particularly relates to a strain for producing high-optical-purity L-lactic acid and application of the strain. The strain is preserved in the China General Microbiological Culture Collection Center (CGMCC) on May 13, 2025, and the preservation number of the strain is CGMCC No. 34537; the preservation address is Institute of Microbiology, Chinese Academy of Sciences, No.3, Yard 1, Beichen West Road, Chaoyang District, Beijing. When the strain is used for fermentation production of L-lactic acid, the fermentation period is short, the sugar-acid conversion rate is high, the yield of L-lactic acid is high, and the optical purity is high. In addition, the strain also has excellent growth and metabolism stability, lactic acid with optical purity can still be efficiently produced after passage to the tenth generation, and the strain is suitable for industrial production of high-purity L-lactic acid.

The invention belongs to the technical field of genetic engineering breeding, and particularly relates to application of an SC8 gene in regulating accumulation of soluble solids in tomato fruits and a breeding method. The SC8 gene provided by the invention plays an important role in tomato saccharic acid metabolism and soluble solid synthesis and accumulation, and plays a role in negative regulation of tomato fruit soluble solid synthesis and accumulation. The SC8 gene is applied to plant genetic engineering breeding, and a new functional site and a new breeding thought are provided for cultivating high-quality flavor tomato varieties. By inhibiting the expression of the SC8 gene, soluble solids and sugar acid metabolites thereof such as cane sugar, fructose, glucose, malic acid and citric acid in the red ripe tomato fruits can be increased, and by enhancing the expression level of the SC8 gene, synthesis and accumulation of the soluble solids in the tomato can be reduced; therefore, the implementation of the invention provides a feasible way for cultivating and producing tomatoes with various flavors and qualities, and plays an important role in improving the economic benefits of the tomato industry.

The present invention relates to a method for the production of a sialylated glycosphingolipid, the method comprising the steps of: ─ providing a glycosphingolipid, a sialic acid donor, and an enzyme having a trans-sialidase activity, ─ mixing said glycosphingolipid with said sialic acid donor in the presence of said enzyme having trans-sialidase activity, thereby producing said sialylated glycosphingolipid, and wherein the sialic acid donor is 3´-sialyllactose.

The invention discloses a modified aureobasidium pullulans strain based on reduction of malic acid pathway consumption and application of the modified aureobasidium pullulans strain. Gene for coding NADPH dependent malic enzyme and phosphoenolpyruvate carboxykinase in an aureobasidium pullulans genome is directionally knocked out. The transformation blocks a key consumption branch for synthesis and accumulation of the cytoplasmic malic acid, and effectively guides a central carbon metabolic flow to be more efficiently guided to a target product. Experimental results show that the polymalic acid yield and the saccharic acid conversion rate of the double-knockout engineering strain D3N5-delta3617 / deltapepck in fermentation are remarkably improved compared with those of an original strain, and the biomass is also increased. The invention provides a high-performance strain with important application value for industrial efficient fermentation production of polymalic acid.

The invention provides a method for improving fermentation yield and sugar-acid conversion rate of 5-hydroxytryptophan, alpha-ketoglutaric acid ferrous salt, alpha-ketoglutaric acid zinc salt, alpha-ketoglutaric acid cobalt salt and alpha-ketoglutaric acid manganese salt are added into a fermentation culture medium according to a specific proportion, alpha-ketoglutaric acid directly participates in TCA circulation, circulation operation can be accelerated, generation of NADH and FADH2 is increased, the yield of 5-hydroxytryptophan is increased, and the yield of 5-hydroxytryptophan is increased. The ATP synthesis efficiency is improved, and more energy is provided for cell growth; the alpha-ketoglutaric acid can balance amino acids required in the growth process of escherichia coli, promote the generation of proteins and nucleic acids and accelerate the growth of thalli; the alpha-ketoglutaric acid metal salt can improve the utilization efficiency of microelements by thalli; ferrous ions are cofactors of 5-hydroxytryptophan hydroxylase and can accelerate the hydroxylation process of tryptophan. Through the synergistic effect of the added components, the yield of the 5-hydroxytryptophan and the sugar-acid conversion rate are improved.

The invention belongs to the field of synthetic biology, and particularly relates to a genetically engineered bacterium for producing O-succinyl-L-homoserine at high yield as well as a construction method and application of the genetically engineered bacterium. According to the invention, the large intestine probiotic Nissle 1917 is used as a chassis strain, and compared with other expression hosts, the large intestine probiotic Nissle 1917 can grow and breed more quickly and is safer. The expression of the gene thrB is regulated by using the self-regulation promoter PfliA, so that the synthesis route of threonine is dynamically regulated, the efficient utilization of a carbon source is realized, and the sugar acid conversion rate of OSH synthesis is improved; in addition, by introducing site mutation, feedback inhibition suffered by OSH synthesis key enzyme HST is relieved, the enzyme activity of consumption pathway key enzyme CGS is reduced, and the carbon flow is effectively driven to be redirected to a target product synthesis pathway. According to the microbial cell factory constructed by the invention, the production efficiency of OSH is remarkably improved, the fermentation period is shortened, the production cost is reduced, and the economic feasibility of industrial production is realized.

The invention discloses a nutrition regulating agent for regulating the mature period of citrus fruits and application of the nutrition regulating agent. The nutrition regulating agent is prepared from potassium nitrate, monopotassium phosphate, magnesium sulfate, ferric sodium ethylenediaminetetraacetate, zinc sodium ethylenediaminetetraacetate, boric acid, ammonium molybdate, gibberellin, abscisic acid and diatomite which is supplemented to 100 parts. The invention further provides a preparation method of the nutrition regulating agent and application of the nutrition regulating agent in regulating the mature period of citrus fruits, and the application mode is that when the diameter of the citrus fruits is 40-50 mm, the preparation is diluted by 600-800 times to be sprayed on leaf surfaces, once every 7 days and twice continuously. Through the synergistic effect of mineral nutrient elements and low-concentration hormones, bidirectional precise regulation and control of the citrus mature period are achieved, fruits can be promoted to mature in advance or later for 7-15 days, the sugar-acid ratio and color of the fruits can be remarkably improved, meanwhile, the problems of tree vigor decline and quality decline caused by single hormone treatment are solved, and the method is suitable for large-scale popularization and application. The method has the characteristics of high efficiency, safety and simple operation.

The application provides a compound microbial fertilizer, a preparation method and application thereof. The compound microbial fertilizer comprises the following components in parts by weight: 10-30 parts of a compound microbial agent, 20-50 parts of an agent carrier, 30-50 parts of a compound fertilizer slow-release agent and 10-30 parts of modified urea aldehyde. The compound microbial fertilizer prepared by the application can be applied to growth tests of tomatoes, and higher yield, stem thickness growth value, vitamin C content and sugar acid ratio can be obtained. The compound microbial fertilizer has long-term effect, can release phosphorus, nitrogen and potassium and the like, has the effects of moisturizing and loosening soil, can increase the yield and quality of tomato fruits, promote the robustness of roots and stems and improve the eating taste.