Publications by authors named "Zheng-Qiang Jiang"

To retard starch retrogradation and improve bread quality, a novel maltotetraose-forming amylase (AhMFA) from Atopomonas hussainii was expressed in Komagataella phaffii. After high cell density fermentation, the enzyme activity reached a maximum level of 3032 U mL. AhMFA showed optimal activity at pH 6.

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For applications in food industries, a fungal α-amylase from Malbranchea cinnamomea was engineered by directed evolution. Through two rounds of screening, a mutant α-amylase (mMcAmyA) was obtained with higher optimal temperature (70 °C, 5 °C increase) and better hydrolysis properties (18.6 % maltotriose yield, 2.

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2'-Fucosyllactose (2'-FL) is known for its ability to provide various health benefits to infants, such as gut maturation, pathogen resistance, improved immunity, and nervous system development. However, the production of 2'-FL using α-L-fucosidases is hindered by the lack of low-cost natural fucosyl donors and high-efficiency α-L-fucosidases. In this work, a recombinant xyloglucanase from Rhizomucor miehei (RmXEG12A) was applied to produce xyloglucan-oligosaccharide (XyG-oligos) from apple pomace.

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Functional oligosaccharides exert obesity-reducing effects by acting at various pathological sites responsible for the development of obesity. In this study, tamarind xyloglucan oligosaccharides (TXOS) were used to attenuate metabolic disorders via the gut-liver axis in mice with high-fat-diet (HFD)-induced obesity, as determined through LC/MS-MS and 16S rRNA sequencing technology. A TXOS dose equivalent to 0.

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The present supply of prebiotics is entirely inadequate to meet their demand. To produce novel prebiotics, a d-mannose isomerase (MIaseA) from was first produced in (). MIaseA shared the highest amino acid sequence identity (58.

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Partially hydrolyzed konjac powder (PHKP) can be used to increase the daily intake of dietary fibers of consumers. To produce PHKP by enzymatic hydrolysis, a novel β-mannanase gene (McMan5B) from Malbranchea cinnamomea was expressed in Pichia pastoris. It showed a low identity of less than 52% with other GH family 5 β-mannanases.

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Article Synopsis
  • The xyloglucanase gene (RmXEG12A) from the fungus Rhizomucor miehei was successfully expressed in the yeast Pichia pastoris, showing a high enzyme activity of 25,700 U/mL through high cell density fermentation.
  • The enzyme performs best at pH 7.0 and a temperature of 65 °C, specifically breaking down xyloglucan with a notable activity rate.
  • Hydrolysis of tamarind powder produced xyloglucan oligosaccharides, which enhanced the water holding capacity of yogurt and significantly promoted the growth of beneficial bacteria in the yogurt.
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β-N-acetylhexosaminidases have attracted much attention in recent years due to their potential application in oligosaccharide production, in particular lacto-N-triose II (LNT2) and lacto-N-neotetraose (LNnT) synthesis, which can be further used as backbone precursors for human milk oligosaccharides. A novel β-N-acetylhexosaminidase gene from Tyzzerella nexilis (TnHex189) was heterologously expressed in Bacillus subtilis. The highest β-N-acetylhexosaminidase activity of 14.

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To produce manno-oligosaccharides from cassia gum, a mutated glycoside hydrolase family 134 β-mannanase gene (mRmMan134A) from Rhizopus microsporus var. rhizopodiformis F518 was expressed in Pichia pastoris and a high expression level (3680 U mL) was obtained through high cell density fermentation. mRmMan134A exhibited maximum activity at pH 5.

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A novel α-amylase gene (RmAmyA) from Rhizomucor miehei was cloned and expressed in Pichia pastoris. RmAmyA showed 70% amino acid identity with the α-amylase from Rhizomucor pusillus. A high α-amylase activity of 29,794.

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A novel α-amylase gene (TdAmyA) with an open reading frame of 1431 bp, deducing 476 amino acids, was cloned from the thermophilic fungus Thermomyces dupontii L18. The recombinant α-amylase was successfully over-expressed in Pichia pastoris. The highest α-amylase activity of 38,314 U/mL was obtained with protein content of 28.

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Article Synopsis
  • Mannan, a component of hemicellulose from plants, is broken down by β-mannanases like the cloned enzyme RmMan134A from Rhizopus microsporus, which performs best at pH 5.0 and 50°C with high activity on locust bean gum.
  • The study analyzed the enzyme's substrate-binding mechanism by solving complex structures, revealing a total of at least seven subsites in its catalytic groove that interact with mannose and hinder bonding with galactose.
  • Various binding modes showed that certain subsites are essential for hydrolysis, while rational design efforts improved the enzyme's activity and conditions for optimal performance.
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Article Synopsis
  • - An engineered enzyme called β-mannanase (mRmMan5A) was successfully produced in the yeast Pichia pastoris, achieving a high expression level of 79,680 U/mL.
  • - The enzyme operates best at a pH of 4.5 and a temperature of 65°C, showing strong effectiveness in breaking down mannans.
  • - Using steam explosion to pretreat palm kernel cake (PKC), the mRmMan5A enzyme yielded 34.8 grams of manno-oligosaccharides per 100 grams of dry PKC, successfully demonstrating the potential for mass production with a total yield of 261.3 grams from 1.0 kg of dry PKC
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  • A novel β-mannanase gene (RmMan5A) from the fungus Rhizomucor miehei was successfully expressed in yeast to produce partially hydrolyzed guar gum (PHGG), a dietary fiber.
  • After a 168-hour fermentation, the enzyme yielded a high activity level of 85,200 UmL, optimizing at pH 7.0 and 65°C.
  • The resulting PHGG had a significant dietary fiber content (90.6%) and was further fractionated into various forms with different molecular weights and sugar ratios, showcasing its structural diversity.
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Background: β-Mannanase randomly cleaves the β-1,4-linked mannan backbone of hemicellulose, which plays the most important role in the enzymatic degradation of mannan. Although the industrial applications of β-mannanase have tremendously expanded in recent years, the wild-type β-mannanases are still defective for some industries. The glycoside hydrolase (GH) family 5 β-mannanase (Man5A) from shows many outstanding properties, such as high specific activity and hydrolysis property.

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A novel endo-β-1,3-1,4-glucanase gene (PbBglu16A) was cloned from Paenibacillus barengoltzii and heterogeneously expressed in Escherichia coli. The recombinant β-1,3-1,4-glucanase (PbBglu16A) was purified to homogeneity with a recovery yield of 78.6% and a specific activity of 431.

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In this study, a comparative analysis on the distribution of protease activities among 90 plant resources, including fruits and vegetables, has been performed. Protease activities of plant extracts were assayed at different pH values (pH 3.0, pH 7.

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Bacillus subtilis LM 4-2, a Gram-positive bacterium was isolated from a molybdenum mine in Luoyang city. Due to its strong resistance to molybdate and potential utilization in bioremediation of molybdate-polluted area, we describe the features of this organism, as well as its complete genome sequence and annotation. The genome was composed of a circular 4,069,266 bp chromosome with average GC content of 43.

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Article Synopsis
  • Multiple proteases were used to break down rice residue protein (RRP), leading to the creation of a novel antioxidant peptide fraction (RRPB3) with potent antioxidant properties.
  • * RRPB3 contains four peptides with specific amino acid sequences and various molecular weights, which were identified and characterized through advanced purification techniques.
  • * The synthesized peptides demonstrated strong antioxidant activities and stability against digestive enzymes, indicating their potential for use in food and pharmaceutical applications.
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Purification and characterization of a chymosin from Rhizopus microsporus var. rhizopodiformis were investigated in the present study. A newly isolated R.

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The family 10 xylanase (XynB) from Thermotoga maritima MSB8 is extremely thermostable and great potential in the applications of various fields of industry. The gene mxynB(64) was amplified by the method of PCR with the template of the genomic DNA of Thermotoga maritima MSB8, and cloned into the expression vectors of Escherichia coli and Pichia pastoris respectively. Xylanase B(40kD) was successfully expressed by the two heterologous protein expression systems with high-level production.

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Besides affecting the xylanases production, different nitrogen sources present in the media also caused changes in the xylanosomal subunit composition of Streptomyces olivaceoviridis E-86. Four xylanosome fractions, purified from the culture supernatant of S. olivaceoviridis E-86 grown on different nitrogen sources, exhibited high specificity towards different xylans and were composed of different subunits.

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The production of a novel, very large xylanolytic complex (xylanosome) by Streptomyces olivaceoviridis E-86 is reported. The molecular weight was approx. 1200 kDa as determined by native gradient gel electrophoresis.

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