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781.
782.
Yin-Hua Shih Kuo-Wei Chang Shih-Min Hsia Cheng-Chia Yu Lih-Jyh Fuh Tzu-Yun Chi Tzong-Ming Shieh 《Microbiological research》2013,168(5):254-262
Hinokitiol is a natural component isolated from Chamacyparis taiwanensis. It has anti-microbial activity, and has been used in oral care products. The minimal inhibitory concentration (MIC) and minimal microbicidal concentration (MMC) of hinokitiol against MRSA, Aggregatibacter actinomycetemcomitans, Streptococcus mutans, and Candida albicans were determined by the agar and broth dilution method (MIC: 40–110 μM; MMC: 50–130 μM); the paradoxical inhibition phenomenon (PIP) was observed in A. actinomycetemcomitans and S. mutans. The PIP can be described as microbial growth occurring in the presence of both high and low concentrations of a compound, between which microbial growth is inhibited. The PIP was confirmed using a kinetic microplate and inhibition zone methods. The PIP was also observed in MRSA. The low autolysin activity somehow correlated to the PIP positive. The cell diameter was increased in all the pathogens, and the transition was inhibited in C. albicans following hinokitiol treatment. Hinokitiol is also a potential anticancer drug. The 200 μM of hinokitiol has significant antimicrobial and cytotoxic activities against oral pathogens and oral squamous cell carcinoma cell lines, respectively, and lower cytotoxic effects for normal human oral keratinocytes, indicating that hinokitiol displays a high potential for safe and effective applications in oral health care. 相似文献
783.
Yong-Suk Lee Yi Zhou Dong-Ju Park Jie Chang Yong-Lark Choi 《World journal of microbiology & biotechnology》2013,29(5):865-873
The gene encoding the cyclodextrin glucanotransferase (CGTase, EC2.4.1.19) of Paenibacillus illinoisensis was isolated, cloned, sequenced and expressed in Escherichia coli. Sequence analysis showed that the mature enzyme (684 amino acids) was preceded by a signal peptide of 34-residues. The deduced amino acid sequence of the CGTase from P. illinoisensis ZY-08 exhibited highest identity (99 %) to the CGTase sequence from Bacillus licheniformis (P14014). The four consensus regions of carbohydrate converting domain and Ca2+ binding domain could be identified in the sequence. The CGTase was purified by using cold expression vector, pCold I, and His-tag affinity chromatography. The molecular weight of the purified enzyme was about 74 kDa. The optimum temperature and pH of the enzyme were 40 °C and pH 7.4, respectively. The enzyme activity was increased by the addition of Ca2+ and inhibited by Ba2+, Cu2+, and Hg2+. The K m and V max values calculated were 0.48 mg/ml and 51.38 mg of β-cyclodextrin/ml/min. The ZY-08 and recombinant readily converted soluble starch to β-cyclodextrin but ZY-08 did not convert king oyster mushroom powder and enoki mushroom powder. However the recombinant CGTase converted king oyster mushroom powder and enoki mushroom powder to β-cyclodextrin. 相似文献
784.
785.
Saburo Tamura Ching-Fun Chang Akinori Suzuki Sumio Kumai 《Bioscience, biotechnology, and biochemistry》2013,77(3):391-397
Two new isoflavonoids were isolated from red clover as germination inhibitors for the same plant and their structures were determined as a glucoside of biochanin A (7-d-β-glucosyl-5,7-dihydroxy-4′-methoxyisoflavone) (II) and its 5-malonate (I), respectively. Besides these compounds the following substances were also isolated as inhibitors: trifolirhizin (III), ononin (IV), daidzein (V) and its 7-glucoside (VI), formononetin (VII), genistein (VIII) and biochanin A (IX). 相似文献
786.
Toshiya Kamikado Ching-Fun Chang Shigeo Murakoshi Akira Sakurai Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(4):833-836
Two lignans were isolated from leaves of Magnolia kobus DC. as growth inhibitors on silkworm larvae and structurally elucidated as sesamin (I) and kobusin (II) which has been hitherto unknown. 相似文献
787.
Hyunji Lee Hyeon-Son Choi Yooheon Park Chang Won Ahn Sung Ug Jung Soo Hyun Park 《Bioscience, biotechnology, and biochemistry》2013,77(10):1703-1709
Deer bone extract has the potential to relieve the discomfort or the articular cartilaginous damage associated with osteoarthritic (OA) and may be useful as a natural supplement for OA treatment without serious side effects. We analyzed the expression of pro-inflammatory cytokine and cartilage-related genes in monosodium iodoacetate-induced OA rats. Increases in the levels of serum pro-inflammatory cytokines, such as interleukin-1β, interleukin-6, and tumor necrosis factor-α were significantly inhibited by the administration of deer bone extract (p?<?0.05). Decreases in the expression of collagen type II (COL2) and tissue inhibitors of metalloproteinases (TIMPs) mRNAs in the cartilage were significantly inhibited by deer bone extract treatment (p?<?0.05). The deer bone extract significantly suppressed the expression of matrix metalloproteinases (MMPs) mRNAs in the cartilage. The deer bone extract induced the up-regulation of COL2 and TIMP mRNAs and the down-regulation of MMP mRNAs by suppressing the expression of pro-inflammatory cytokine mRNAs. 相似文献
788.
Ryotaro Myokei Akira Sakurai Ching-Fun Chang Yoshinori Kodaira Nobutaka Takahashi Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(10):1491-1500
A new insecticidal substance named aspochracin was isolated from the culture filtrate of Aspergillus ochraceus, a pathogenic fungus causing muscardine on insects. The compound was found to be a novel cyclotripeptide, composed of N-methyl-l-alanine, N-methyl-l-valine and l-ornithine, containing an octatrienoic acid side chain. Isolation procedure, structural elucidation and biological activities are described in detail.Hexahydroaspochracin (II) derived on hydrogenation of aspochracin (I), an insecticidal metabolite of Aspergillus ochraceus, was synthesized by cyclization of N-methyl-l-valyl-N- methyl-l-alanyl-α-caprylyl-l-ornithine (XIV). In addition to II, isohexahydroaspochracin (XV) was isolated from the reaction mixture. 相似文献
789.
Chiou-Yeong Saw Tsai-Ju Chang Po-Ya Chen Fan-Jhen Dai Yie-Qie Lau Ting-Yu Chen 《Bioscience, biotechnology, and biochemistry》2013,77(12):2327-2333
ABSTRACTThis study was aimed to investigate the presence of Bacillus coagulans vegetative cells in the intestine and fecal samples in rats fed B. coagulans spores as well as to estimate the ratios of spores and vegetative cells in these samples. A two-step process has been developed to enumerate B. coagulans in different mixed bacterial samples, specifically (1) observation of yellow ring formation on modified GYEA medium upon incubation at 55°C, (2) microscopic examination of spore formation after 7 d of incubation. Our results have demonstrated the presence of vegetative cells in the intestinal and fecal samples in rats fed B. coagulans spores. The ratios of B. coagulans spores and vegetative cells in cecal fluid, colonic content, and feces were approximately 2:8, 2:8, and 4:6, respectively. The existence of B. coagulans vegetative cells improved the intestinal milieu through an elevated short-chain fatty acid concentrations, higher fecal moisture, and lower fecal pH. 相似文献
790.
Xiao-Lin Liu Jun Wen Ze-Long Nie Gabriel Johnson Zong-Suo Liang Zhao-Yang Chang 《Journal of plant research》2013,126(3):351-361
Prunus subgenus Padus is a group with a wide distribution in temperate eastern Asia and eastern North America with one species extending to Europe and one to Central America. Phylogenetic relationships of subgenus Padus were reconstructed using sequences of nuclear ribosomal ITS, and plastid ndhF gene, and rps16 intron and rpl16 intron. Prunus subgenus Padus is shown to be polyphyletic. Taxa of subgenus Padus and subgenus Laurocerasus are highly intermixed in both the ITS and the plastid trees. The results support two disjunctions between eastern North America and Eurasia within the Padus group. One disjunction is between Prunus virginiana of eastern North America and P. padus of Eurasia, estimated to have diverged at 2.99 (95 % HPD 0.59–6.15)–4.1 (95 % HPD 0.63–8.59) mya. The other disjunction is between P. serotina and its Asian relatives. The second disjunction may have occurred earlier than the former one, but the age estimate is difficult due to the unresolved phylogenetic position of the P. serotina complex. 相似文献