• 제목/요약/키워드: college of science-engineering

검색결과 10,291건 처리시간 0.045초

Effect of chitosan coating combined with hypotaurine on the quality of shrimp (Litopenaeus vannamei) during storage

  • Chen, Meiyu;Hu, Lingping;Hu, Zhiheng;Zhou, Yaqi;Li, Gaoshang;Chin, Yaoxian;Hu, Yaqin
    • Fisheries and Aquatic Sciences
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    • 제25권2호
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    • pp.64-75
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    • 2022
  • This study aimed to investigate the effect of different coating materials on the quality of shrimp (Litopenaeus vannamei) during chilled storage for 10 days. Fresh shrimp were randomly divided into five groups: the control group, the hypotaurine treatment group (2%), the chitosan group (1%), the hypotaurine + chitosan group (2% hypotaurine solution with 1% of chitosan), and the sodium metabisulfite treatment group (1.25%). Compared with other treatments, the lower accumulation of total visible counts (TVC, 5.25 Log10 CFU/g), total volatile basic nitrogen (TVB-N, 22.5 mg/100 g) and thiobarbituric acid values (TBA, 0.58 mg MDA/kg) suggested that coating of chitosan-hypotaurine could retard the microbial activity, protein degradation and lipid oxidation of shrimp. Meanwhile, results demonstrated that the chitosan coating combined with hypotaurine showed an excellent performance in inhibiting quality deterioration (pH 7.5, ∆E 7.0, hardness 393 g, and elasticity 0.69). Furthermore, the melanosis degree of shrimp was alleviated, and the sensory parameters, including appearance, odor and texture, were maintained to the acceptable level by chitosan based hypotaurine treatment during the chilled storage.

Isolation and Analysis of the Enzymatic Properties of Thermophilic Fungi from Compost

  • Lee, Hanbyul;Lee, Young Min;Jang, Yeongseon;Lee, Sangjoon;Lee, Hwanhwi;Ahn, Byoung Jun;Kim, Gyu-Hyeok;Kim, Jae-Jin
    • Mycobiology
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    • 제42권2호
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    • pp.181-184
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    • 2014
  • To the best of our knowledge, this is the first report on thermophilic fungi isolated in Korea. Three species of thermophiles were isolated from compost and were identified as Myriococcum thermophilum, Thermoascus aurantiacus, and Thermomyces lanuginosus. They can grow at temperatures above $50^{\circ}C$ and produce high levels of cellulolytic and xylanolytic enzymes at high temperatures. Notably, the considerable thermostability of the endo-glucanase produced by T. aurantiacus has made the fungus an attractive source of industrial enzymes.

Investigation of Filamentous Fungi Producing Safe, Functional Water-Soluble Pigments

  • Heo, Young Mok;Kim, Kyeongwon;Kwon, Sun Lul;Na, Joorim;Lee, Hanbyul;Jang, Seokyoon;Kim, Chul Hwan;Jung, Jinho;Kim, Jae-Jin
    • Mycobiology
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    • 제46권3호
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    • pp.269-277
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    • 2018
  • The production of water-soluble pigments by fungal strains indigenous to South Korea was investigated to find those that are highly productive in submerged culture. Among 113 candidates, 34 strains that colored the inoculated potato dextrose agar medium were selected. They were cultured in potato dextrose broth and extracted with ethanol. The productivity, functionality (radical-scavenging activities), and color information (CIELAB values) of the pigment extracts were measured. Five species produced intense yellowish pigments, and two produced intense reddish pigments that ranked the highest in terms of absorbance units produced per day. The pigment extracts of Penicillium miczynskii, Sanghuangporus baumii, Trichoderma sp. 1, and Trichoderma afroharzianum exhibited high radical-scavenging activity. However, the S. baumii extract showed moderate toxicity in the acute toxicity test, which limits the industrial application of this pigment. In conclusion, P. miczynskii KUC1721, Trichoderma sp. 1 KUC1716, and T. afroharzianum KUC21213 were the best fungal candidates to be industrial producers of safe, functional water-soluble pigments.

Welfare traits of Bos indicus cattle castrated immunologically and fed beta-adrenergic agonists

  • Martello, Luciane Silva;Antonelo, Daniel Silva;Consolo, Nara Regina Brandao;Pacheco, Veronica Madeira;Negrao, Joao Alberto;Rosa, Alessandra Fernandes;Leme, Paulo Roberto;Sousa, Rafael Vieira;Silva, Saulo da Luz
    • Animal Bioscience
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    • 제34권9호
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    • pp.1552-1558
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    • 2021
  • Objective: This work was carried out to evaluate the effects of zilpaterol hydrochloride (ZH) and ractopamine hydrochloride (RH) combined with immunocastration on the welfare traits of feedlot Nellore cattle. Methods: Ninety-six Nellore males (average body weight [BW] = 409±50 kg; average 20 mo of age) were divided into two groups according to BW; half of the animals in each group received two doses of an immunocastration (ImC) vaccine in a 30 day interval, and the other half did not receive the vaccine (NoC). Afterward, the animals were housed and fed a common diet for 70 days. Then, they were split into three groups and fed one of the following diets for 30 additional days: control (CO) diet, with no β-AA; ZH diet, containing 80 mg/d ZH; and RH diet, containing 300 mg/d RH. Welfare traits were assessed by monitoring body surface temperature using infrared thermography (IRT) and plasma cortisol and temperament measurements. Results: There was no interaction between sexual condition and diet for any trait. The ImC and NoC groups did not differ in rectal and ocular temperatures. The ImC animals had higher flight speeds (p = 0.022) and tended to have higher cortisol levels (p = 0.059) than the NoC animals. Animals fed ZH and RH did not differ in cortisol levels, respiratory rate, rectal temperature, temperature measured by IRT, or temperament behaviour. Conclusion: The ImC animals showed a less stable temperament during handling practices than NoC, whereas ZH and RH supplementation had no adverse effects on animal welfare.

Purification and Characterization of Neoagarotetraose from Hydrolyzed Agar

  • Jang, Min-Kyung;Lee, Dong-Guen;Kim, Nam-Young;Yu, Ki-Hwan;Jang, Hye-Ji;Lee, Seung-Woo;Jang, Hyo-Jung;Lee, Ye-Ji;Lee, Sang-Hyeon
    • Journal of Microbiology and Biotechnology
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    • 제19권10호
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    • pp.1197-1200
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    • 2009
  • The whitening effect, tyrosinase inhibition, and cytotoxicity of neoagarotetraose were measured after its purification from hydrolyzed agar by gel filtration chromatography. In melanoma B16F10 cells, the melanin content of neoagarotetraose-treated cells was the same as that treated by kojic acid or arbutin. In addition, tyrosinase of melanoma cells was strongly inhibited by neoagarotetraose at a concentration of $1{\mu}g/ml$ and similarly inhibited at 10 and $100{\mu}g/ml$ compared with those by arbutin or kojic acid. The activity of mushroom tyrosinase showed a 38% inhibition by neoagarotetraose at $1{\mu}g/ml$, and this inhibitory effect was more efficient than that by kojic acid. Neoagarotetraose revealed a similar $IC_{50}$ (50% inhibition concentration) value for mushroom tyrosinase as that by kojic acid. These data suggest that the neoagarotetraose generated from agar by recombinant $\beta$-agarase might be a good candidate as a cosmetic additive for the whitening effect.

Preparation of Well-Dispersed Nanosilver in MIL-101(Cr) Using Double-Solvent Radiation Method for Catalysis

  • Chang, Shuquan;Liu, Chengcheng;Fu, Heliang;Li, Zheng;Wu, Xian;Feng, Jundong;Zhang, Haiqian
    • Nano
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    • 제13권12호
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    • pp.1850145.1-1850145.8
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    • 2018
  • In this study, a double-solvent radiation method is proposed to prepare silver nanoparticles in the pores of metal-organic framework MIL-101(Cr). The results reveal that well-dispersed silver nanoparticles with a diameter of about 2 nm were successfully fabricated in the cages of monodisperse octahedral MIL-101(Cr) with a particle size of about 400 nm. The structure of MIL-101(Cr) was not destroyed during the chemical treatment and irradiation. The resulting Ag/MIL-101 exhibits excellent catalytic performance for the reduction of 4-nitrophenol. This method can be extended to prepare other single or bimetallic components inside porous materials.