Publications by authors named "Shukun Yu"

Goji ( L.) is a widely planted crop in China that is easily infected by the pathogenic fungus , which causes rot after harvest. Previous studies showed that carvacrol (CVR) significantly inhibited the mycelial growth of and reduced Alternaria rot in goji fruits .

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  • The study examines starches from three ecotypes of Agriophyllum squarrosum seeds, comparing their properties with quinoa starch.
  • Agriophyllum starches have smaller granule sizes, more branching in amylopectin, and different viscosity and digestibility characteristics compared to quinoa starch.
  • The unique physicochemical properties of Agriophyllum starches suggest potential for their use in food applications and encourage the domestication of A. squarrosum crops.
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  • The study aimed to assess how adding a glucoamylase enzyme impacts fermentation, growth, and carcass traits in cattle fed a corn-based diet.
  • In the first experiment, it was found that adding the enzyme improved dry matter disappearance and altered fermentation by increasing propionate and reducing final pH, while smaller corn particle sizes also enhanced nutrient breakdown.
  • The second experiment showed that including the enzyme in the diet did not significantly change the steers' growth parameters or carcass quality, although higher enzyme inclusion improved feed conversion efficiency slightly.
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  • Two experiments assessed the impact of various doses of α-amylase, glucoamylase, and proteases on the digestibility of mature dent corn grain using a controlled batch culture system.
  • In experiment 1, certain enzymes notably improved in vitro dry matter (IVDMD) and starch digestibility (IVSD), with enzyme 6Afuga causing the greatest increases at 1 mg dosage.
  • Experiment 2 found that lower doses of bacterial proteases significantly enhanced IVDMD and IVSD, indicating that specific enzyme types and amounts can effectively boost corn grain digestibility.
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Two commercial proteases (subtilisin-typed FNA from Bacillus amyloliquefaciens, and chymotrypsin-like NPP from Nocardiopsis prasina), porcine pepsin, porcine pancreatin having protease activity and their combinations were studied in vitro by LC-MS for their ability to digest soy protein isolate (SPI) under conditions close to those found in the stomach (pH 3.7) and small intestine (pH 6.5).

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The aim of this study was to evaluate the effect of two glucoamylases (GA) and the combination of one GA with a neutral protease on apparent total tract digestibility in beef bulls fed a total mixed ration (TMR) rich in rolled corn. Sixteen Angus beef bulls (266 ± 4.9 kg of initial BW, and 182 ± 1.

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  • MnO-CeO catalysts doped with metals like Cu, Fe, Co, and La demonstrated effective catalytic oxidation of chlorobenzene when supported on cordierite.
  • The properties of these catalysts varied significantly based on the different molar ratios of Mn/Ce and M/Mn, which were analyzed using various characterization techniques.
  • CuO-MnO-CeO catalysts showed superior chlorobenzene conversion with a light-off temperature around 400°C, while FeO-MnO-CeO catalysts produced more carbon monoxide due to incomplete oxidation; both types remained stable without deactivation at high temperatures.
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Objective: To investigate and analyze the capabilities of microscopic examinations in medical and health organizations in Dongxihu District, Wuhan City, so as to provide evidences for achieving the standard of malaria elimination and malaria control in the future.

Methods: The basic information of the laboratorians and the hardware facilities in 15 microscopic examination stations of were collected and analyzed from 2010 to 2015. Meanwhile, the quality of making, dyeing, cleanliness of all the negatives blood smears were evaluated, and all the positive smears were re-checked in the district during the period above mentioned.

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This study was conducted to evaluate the efficacy of a novel Buttiauxella phytase to pigs fed P-deficient, corn-soybean meal diets. One hundred and twenty crossbred piglets (9.53 ± 0.

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Ferulic acid dehydrodimers (DFA) and dehydrotrimers (TriFA) ester-linked to plant cell wall polymers may cross-link not only cell wall polysaccharides but also other cell wall components including proteins and lignin, thus enhancing the rigidity and potentially affecting the enzymatic degradation of the plant cell wall. Corn, wheat, and mixed-cereal distiller's dried grains with solubles (DDGS) were investigated for composition of DFAs and TriFAs by reversed phase high-performance liquid chromatography with ultraviolet detection. Corn DDGS contained 5.

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  • Ochratoxin A is a harmful mycotoxin produced by Aspergillus and Penicillium species, found in various agricultural products, posing significant health risks.
  • A novel ochratoxinase enzyme from Aspergillus niger was characterized, showing improved efficiency in degrading ochratoxin A compared to previously known enzymes.
  • The enzyme, which is thermostable and functions optimally at pH ~6 and 66°C, features a unique two-domain structure and a metal-dependent active site crucial for its catalytic activity.
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α-Glucosidase is in the glycoside hydrolase family 13 (13AG) and 31 (31AG). Only 31AGs can hydrate the D-glucal double bond to form α-2-deoxyglucose. Because 1,5-anhydrofructose (AF), having a 2-OH group, mimics the oxocarbenium ion transition state, AF may be a substrate for α-glucosidases.

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The enzyme aldos-2-ulose dehydratase/isomerase (AUDH) participates in carbohydrate secondary metabolism, catalyzing the conversion of glucosone and 1,5-d-anhydrofructose to the secondary metabolites cortalcerone and microthecin, respectively. AUDH is a homo-dimeric enzyme with subunits of 900 amino acids. The subunit consists of a seven-bladed β-propeller domain, two cupin folds and a C-terminal lectin domain.

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  • Phytase breaks down phytate in grains to release bioavailable inorganic phosphate, but traditional assays for measuring this activity are time-consuming and hazardous.
  • The article introduces a new kinetic assay method that uses IP(6)-lysozyme complexes, which simplifies the process and can be adapted for high-throughput testing.
  • This method effectively measures phytase activity by monitoring changes in turbidity, while also investigating how different conditions like temperature and salt concentrations affect the assay results.
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1,5-Anhydro-D-fructose (AF) is a mono-saccharide directly formed from starch and glycogen by the action of α-1,4-glucan lyase (EC 4.2.2.

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1,5-Anhydro-D-fructose (AF) was first found in fungi and red algae. It is produced by the degradation of glycogen, starch and maltosaccharides with α-1,4-glucan lyase (EC 4.2.

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  • 1,5-Anhydro-D-fructose (1,5AnFru) is a type of sugar that can be produced from starch or D-glucose/D-fructose with high efficiency.
  • This sugar can be modified through enzymatic or chemical methods to create new carbohydrate derivatives that may have biological activities.
  • Examples of these derivatives include compounds with antimicrobial and antioxidant properties, as well as natural products like 1-deoxymannonojirimycin and Clavulazine.
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In the present paper, the authors study the photolumimescence spectra of the novel 2,3-tetra-(2-isopropyl-5-methylbenzoyl) hydrogen phthalocyanine casting film and vacuum-deposited film. Photolumimescence spectras of casting film on the quartz substrate were measured at 10, 77, 177 and 300 K, and the photolumimescence spectra of vacuum-deposited film with a thickness of about 200 nm on the silicon substrate was studied at room temperature (300 K). For 2,3-tetra-(2-isopropyl-5-methylbenzoyl) hydrogen phthalocyanine, the casting films all show fluorescence peaks at 942, 937, 942 and 942 nm and phosphorescence peaks at 1114, 1057, 1114 and 1114 nm in the photolumimescence spectra at 10, 77, 177 and 300 K, respectively.

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In many living forms, glucose is stored in the polymeric form of glycogen and starch as a source of carbon and energy. Upon need, these polymers are broken down to their building block glucose in the presence of water and hydrolases, and glucose 1-phosphate in the presence of phosphate and phosphorylase. In the last decade, we established an alternative glycogen catabolic pathway, the so-called Anhydrofructose (AF) pathway, the description of which was approved by IUBMB in 2006.

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Anhydrofructose (AF) pathway describes the catabolism of alpha-1,4-glucans of glycogen, starch and maltosaccharides to various metabolites via the central intermediate AF. The reaction sequence of the pathway consists of more than 10 enzymatic steps. This pathway occurs in certain bacteria, fungi, algae and mammals.

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  • The bacterium Sinorhizobium morelense S-30.7.5 can metabolize the sugar 1,5-anhydro-D-fructose (AF) using a novel pathway that converts it to 1,5-anhydro-D-mannitol (AM) and then to D-mannose.
  • The enzyme responsible for this metabolism, a new NADPH-dependent monomeric reductase named AFR, is specifically effective in reducing AF, but does not act on common aldoses or ketoses.
  • Sequence analysis revealed similarities between AFR and other oxidoreductases from various bacteria, suggesting a shared evolutionary background and potential applications in sugar analysis and synthesis.
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Recombinant barley high pI alpha-glucosidase was produced by high cell-density fermentation of Pichia pastoris expressing the cloned full-length gene. The gene was amplified from a genomic clone and exons (coding regions) were assembled by overlap PCR. The resulting cDNA was expressed under control of the alcohol oxidase 1 promoter using methanol induction of P.

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  • The anhydrofructose pathway involves breaking down glycogen and starch into 1,5-anhydro-D-fructose (1,5AnFru) and converting it to ascopyrone P (APP).
  • This study examined the antibrowning effects of 1,5AnFru and APP on various fruits, vegetables, and beverages, finding 1,5AnFru effective in green tea and black currant wine, while APP was comparable to kojic acid across several agricultural products.
  • Mechanism studies revealed that both APP and kojic acid inhibit plant polyphenol oxidase and can decolor quinones, contributing to their antibrowning properties.
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