• Journal of Microbiology and Biotechnology
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• 제31권5호
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• pp.676-685
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• 2021

RNA-binding proteins are involved in RNA metabolism and posttranscriptional regulation of various fundamental biological processes. The PUF family of RNA-binding proteins is highly conserved in eukaryotes, and its members regulate gene expression, mitochondrial biogenesis, and RNA processing. However, their biological functions in Aspergillus species remain mostly unknown in filamentous fungi. Here we have characterized the puf genes in the model organism Aspergillus nidulans. We generated deletion mutant strains for the five putative puf genes present in the A. nidulans genome and investigated their developmental phenotypes. Deletion of pufA or pufE affected fungal growth and asexual development. pufA mutants exhibited decreased production of asexual spores and reduced mRNA expression of genes regulating asexual development. The pufE deletion reduced colony growth, increased formation of asexual spores, and delayed production of sexual fruiting bodies. In addition, the absence of pufE reduced both sterigmatocystin production and the mRNA levels of genes in the sterigmatocystin cluster. Finally, pufE deletion mutants showed reduced trehalose production and lower resistance to thermal stress. Overall, these results demonstrate that PufA and PufE play roles in the development and sterigmatocystin metabolism in A. nidulans.

• 한국축산식품학회지
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• 제42권5호
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• pp.849-860
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• 2022

The myofibril protein (MP) isolate-saccharide graft reactions was prepared using the Maillard reaction with saccharides. The effects of various saccharides on protein functionality and quality of the Maillard reaction were investigated and compared with those of MP. The grafting degree of the MP isolate-saccharide graft reaction was significantly higher in the reducing sugar-treated groups (lactose, glucose, fructose, and palatinose). The browning intensity of the MP isolate-saccharide graft reaction with fructose, sucrose, and erythitol was higher than that observed in the control reaction (p<0.05). MP that reacted with reducing sugars (glucose, fructose, palatinose, and lactose) had fainter bands than MP that reacted with non-reducing sugars (sucrose, erythitol, trehalose, sorbitol, and xylitol). MPs conjugated with glucose exhibited higher protein solubility. The palatinose and lactose treatments were maximum in water binding capacity, though no significant difference in oil binding capacity among the saccharide treatments was observed. The emulsion stability of the MP isolate-saccharide graft reaction with palatinose and erythitol was higher than that of the control reaction. Therefore, reducing sugars have good protein functionality in the MP isolate-saccharides graft reaction.

• Journal of Plant Biotechnology
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• 제50권
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• pp.27-33
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• 2023

Zizyphus jujube is a plant in the buckthorn family (Rhamnaceae) that has been the subject of research into antibacterial, antifungal and anti-inflammatory properties of its fruit and seed. However, few studies have investigated its leaves. In this study, the anti-inflammatory activity of ZJL (an extract of Z. jujube leaf) was evaluated to verify its potential as an anti-inflammatory agent and SARS-CoV-2 medicine, using nitric oxide (NO) assay, RT-PCR, SDSPAGE, Western blotting, and UHPLC/TOFHRMS analysis. We found that ZJL suppresed pro-inflammatory mediators such as NO, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and tumor necrosis factor α (TNF-α) in lipopolysaccharide (LPS)-induced RAW264.7 cells. ZJL acted by inhibiting NF-KB and MAPK signaling pathway activity. We also confirmed that ZJL contains a phenol compound and flavonoids with anti-inflammatory activity such as trehalose, maleate, epigallocatechin, hyperoside, catechin, 3-O-coumaroylquinic acid, rhoifolin, gossypin, kaempferol 3-neohesperidoside, rutin, myricitrin, guaiaverin, quercitrin, quercetin, ursolic acid, and pheophorbide a. These findings suggest that ZJL may have great potential for the development of anti-inflammatory drugs and vaccines via inhibition of NF-κB and MAPK signaling in LPS-induced RAW264.7 cells.

• Journal of Microbiology
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• 제45권6호
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• pp.505-509
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• 2007

An obligately aerobic bacterium, strain KOPRI $20902^T$, was isolated from a marine sediment in Ny-${\AA}$lesund, Spitsbergen Islands, Norway. Cells were irregular rods and motile with polar monotrichous flagellum. The optimum growth temperature was $17-22^{\circ}C$. Cells grew best in pH 7.0-10.0 and 3-4% sea salts (corresponding to 2.3-3.1% NaCl). The novel strain required $Ca^{2+}$ or $Mg^{2+}$ in addition to NaCl for growth. Sequence analysis of 16S rRNA gene revealed that the Arctic isolate is distantly related with established species (<92.4% sequence similarity) and formed a monophyletic group with Cellvibrio, which formed a distinct phylogenetic lineage in the order Pseudomonadales. Predominant cellular fatty acids [$C_{16:1}\;{\omega}7c/15:0$ iso 2OH (45.3%), $C_{16:0}$ (18.4%), ECL 11.799 (11.2%), $C_{10:0}$ 3OH (10.4%)]; DNA G+C content (37.0 mol%); nitrate reduction to nitrogen; absence of aesculin hydrolysis, N-acetyl-${\beta}$-glucosaminidase and esterase; no assimilation of arabinose, galactose, glucose, lactose, maltose, and trehalose differentiated the strain from the genus Cellvibrio. Based on the phylogenetic and phenotypic characteristics, Dasania marina gen. nov., sp. nov. is proposed in the order Pseudomonadales. Strain KOPRI $20902^T$ (=KCTC $12566^T$=JCM $13441^T$) is the type strain of Dasania marina.

• Plant Biotechnology Reports
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• 제4권2호
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• pp.139-148
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• 2010

Jatropha curcas L. (Physic nut) is a commercially important non-edible oil seed crop known for its use as an alternate source of biodiesel. In order to investigate the morphogenic potential of immature embryo, explants from four developmental stages were cultured on medium supplemented with combinations of auxins and cytokinins. It was found that the size of embryo is critical for the establishment of callus. Immature embryos (1.1-1.5 cm) obtained from the fruits 6 weeks after pollination showed a good response of morphogenic callus induction (85.7%) and subsequent plant regeneration (70%) with the maximum number of plantlets (4.7/explant) on Murashige and Skoog's (MS) medium supplemented with IBA (0.5 $mg\;l^{-1}$) and BA (1.0 $mg\;l^{-1}$). The above medium when supplemented with growth adjuvants such as 100 $mg\;l^{-1}$ casein hydrolysate + 200 $mg\;l^{-1}$ L-glutamine + 8.0 $mg\;l^{-1}$ $CuSO_4$ resulted in an even higher frequency of callus induction (100%). Plant regeneration (90%) with the maximum number of plantlets (10/explant) was achieved on MS medium supplemented with 500 $mg\;l^{-1}$ polyvinyl pyrrolidone + 30 $mg\;l^{-1}$ citric acid + 1 $mg\;l^{-1}$ BA + 0.5 $mg\;l^{-1}$ Kn + 0.25 $mg\;l^{-1}$ IBA. It was observed that plantlet regeneration could occur either through organogenesis of morphogenic callus or via multiplication of pre-existing meristem in immature embryos. The age of immature embryos and addition of a combination of growth adjuvants to the culture medium appear to be critical for obtaining high regeneration rates. Well-developed shoots rooted on half-halfstrength MS medium supplemented with 0.5 $mg\;l^{-1}$ IBA and 342 $mg\;l^{-1}$ trehalose. The rooted plants after acclimatization were successfully transferred to the field in different agro-climatic zones in India. This protocol has been successfully evaluated on five elite lines of J. curcas.

• Mycobiology
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• 제31권1호
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• pp.36-41
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• 2003

Influence of physiological and environmental factors on an antagonistic strain of Trichoderma viride RSR7 were studied optimize its biocontrol potential. The growth and sporulation of T. viride was greatly influenced by various carbon and nitrogen sources, and the environmental factors such as pH and temperature. The best growth and sporulation of T. viride was observed when sucrose, peptone and trehalose were supplemented in the medium as sole carbon sources. Rhamnose, pyruvic acid and sorbitol also supported a good growth. However, with these carbon sources the sporulation was poor. Growth and sporulation was also affected by various nitrogen sources. Growth and sporulation both were favoured by ammonium forms of nitrogen compared to nitrite or nitrate forms. Urea did not support either growth or sporulation. Among amino acids, glutamic acid, asparagine, leucine, aspartic acid, glutamic acid and alanine supported good growth as well as sporulation. T. viride was able to utilize large number of amino acids as sole nitrogen source. Proline was good for growth, but not for sporulation. Maximum growth and sporulation of T. viride was between pH 4.5 to 5.5. Temperatures between $20^{\circ}C\;and\;37^{\circ}C$ were good for both growth and sporulation of T. viride. At lower temperatures(i.e. below $20^{\circ}C$) growth and sporulation were inhibited. Based on the present study it may be concluded that T. viride RSR7 is capable of growing and sporulating with varied nutritional and environmental conditions and, therefore, this strain of T. viride may be useful as a biocontrol agent under diverse physiological and environmental conditions.

• Journal of Microbiology and Biotechnology
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• 제30권8호
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• pp.1207-1213
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• 2020

Aflatoxin B1 (AFB1) is a mycotoxin produced by Aspergillus flavus (A. flavus). AFB1 is reported to have high thermal stability and is not decomposed by heat treatment during food processing. Therefore, in this study, knowing that AFB1 is metabolized by cytochrome P450 (CYP), our aim was to develop a method to detoxify A. flavus-contaminated maize, under normal temperature and pressure, using Escherichia coli expressing human CYP3A4. First, the metabolic activity of AFB1 by recombinant human CYP3A4 was evaluated. As a result, we confirmed that recombinant human CYP3A4 metabolizes 98% of AFB1. Next, we found that aflatoxin Q1, a metabolite of AFB1 was no longer mutagenic. Furthermore, we revealed that about 50% of the AFB1 metabolic activity can be maintained for 3 months when E. coli expressing human CYP3A4 is freeze-dried in the presence of trehalose. Finally, we found that 80% of AFB1 in A. flavus-contaminated maize was metabolized by E. coli expressing human CYP3A4 in the presence of surfactant triton X-405 at a final concentration of 10% (v/v). From these results, we conclude that AFB1 in A. flavus-contaminated maize can be detoxified under normal temperature and pressure by using E. coli expressing human CYP3A4.

• 농업과학연구
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• 제37권3호
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• pp.355-360
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• 2010

This experiment was focused to determine the effect of preharvest treatment of alkaine-reduced water (ARW) and $CaCl_2$ on the storage of oyster mushroom. ARW was prepared through electrolysis of water with $CaCl_2$ (0.1%) as salts and $CaCl_2$ (0.1%) was dissolved in deionized water. Mushrooms were harvested after two sprays of each solutions and quality factors including firmness and browning was determined during storage. The severity of browning was more greater when stored 20 days. Unlike $CaCl_2$, ARW containing 139 ug/L calcium was positive on maintaining freshness in terms of delay of firmness loss and respiration drop, keeping soluble carbohydrate content such as trehalose, and inhibiting the occurrence of browning. Browning, however, seemed to be more influenced by the developmental stage of mushroom at harvest. Even no significant difference was found, the level of ${\beta}$-glucan was low in ARW treatment compared to that of control. Further research including application and preparation methods of ARW is required to clarify the potential of ARW on keeping freshness of oyster mushroom through inhibiting tissue browning.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2002년도 제9차 국제심포지움 및 추계정기학술발표회
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• pp.61-61
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• 2002

무리우산버섯(Kuehneromyces mutabilis)의 온도별 균사생장을 조사한 결과, 균사생장온도는 4~32$^{\circ}C$였으며, 최적 균사생장 온도는 $25^{\circ}C$였고, $25^{\circ}C$~32$^{\circ}C$에서도 비교적 균사생장이 양호하였다. pH별 균사생장도를 조사한 결과는 pH가 4.0, 5.0, 6.0, 7.0, 8.0으로 조절된 YMPG(Yeast Malt Peptone Glucose) 배지에서 균사생장을 조사한 결과 최적 pH는 5.0이 었고, 6.0, 7.0 순으로 균사생장이 양호하였던 반면, 8.0에서는 균사생장이 극히 불량하였다. 아위버섯의 균사생장을 위한 최적 배지조성은 7종의 탄소원을 각각 1%(w/w)농도로 첨가하여 배지를 조제하여 균사생장도를 조사한 결과 glucose, mannose 첨가구에서 균사생장이 가장 양호하였고, frctose, trehalose, starch, dextrin, lactose 순으로 균사생장이 비교적 양호하였던 반면, 다른 탄소원에서는 불량하였다. 질소원별 균사 생장량을 조사한 결과 6종의 질소원을 각각 1% (w/v)농도로 첨가하여 배지를 조제하여 균사생장도를 조사질소원별 균사생장량을 조사한 결과 yeast extract와 peptone 첨가구에서 균사생장량이 매우 양호하였다. 위의 내용을 종합해보면 무리우산버섯의 최적온도는 25~32$^{\circ}C$, 최적 pH는 5.0~6.0으로 나타났다. 또한 적정 영양원은 기본배지로 선발된 YMPG에 탄소원은 mannose, glucose, 질소원은 yeast extract와 peptone에서 가장 양호하였다.

• 한국수정란이식학회지
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• 제28권3호
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• pp.265-271
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• 2013

Cryopreservation and in vitro fertilization (IVF) protocols are important in genetic studies and applications to transgenic animals. Various studies about boar sperm cryopreservation have been studied for a long time. Those were about the use of extenders, the choice of sugars, the cooling and warming rates. The factors that influence the boar sperm are the dramatic changes in temperatures, osmotic and toxic stresses, and reactive oxygen species (ROS) generation. Among these factors, ROS generation is the main damage to DNA which is a principal genetic material and the most important for the practical applications. So we wondered whether ROS generation could be reduced. In previous study, monothioglycerol (MTG) was essential for the culture of embryo stem cells. Therefore we added MTG in the freezing extender based on lactose-egg yolk (LEY) with trehalose. For the assessment of the frozen-thawed sperm, we focused onmotility, membrane integrity and DNA damage. First, we used a computer-aided sperm analysis system for overall conditions of sperm such as motility and viability. Then we performed the sperm chromatin structure assay for DNA integrity and hypo-osmotic swelling test for membrane integrity. And our result showed the existence of MTG in the freezing extender caused less damage to DNA and higher motility in frozen-thawed boar sperm. Also we checked a relative antioxidant activity of MTG in modified Modena B extender. We concluded that this reagent can activate sperm mitochondria at MTG $0.2{\mu}M$, contribute to sperm motility and DNA integrity but there was no significant difference on membrane integrity. Also antioxidant activity of MTG in modified Modena B extender was proved.