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1.
Betulinic and oleanolic acids isolated from Forsythia suspensa
Vahl inhibit urease activity of Helicobacter pylori 总被引:1,自引:0,他引:1
Seung-Jung Shin Chan-El Park Nam-In Baek In Sik Chung Chang-Ho Park 《Biotechnology and Bioprocess Engineering》2009,14(2):140-145
Sixteen medicinal herbs were selected from a database on traditional herbal materials as well as literature on Korean plant
resources. Then ethanol (70%, v/v) extracts of these herbs were tested for inhibition of the urease activity of Helicobacter pylori. The urease activity of H. pylori was strongly (82%) inhibited by extract of Forsythia suspensa
Vahl. Active compounds in extract of Forsythia suspensa
Vahl were first separated by batch mode solvent extraction, followed by purification by silica gel and octadecyl silica gel column
chromatography using solvents of different polarity. According to NMR analysis of the last chromatographic fraction, we identified
the presence of betulinic acid and oleanolic acid, which are known to have anti-inflammatory, anti-cancer, and anti-HIV viral
activities. 相似文献
2.
Kyo Seong Seo Kwang Ho Choo Ho Nam Chang Joong Kon Park 《Applied microbiology and biotechnology》2009,83(2):217-223
The biochemical oxygen demand (BOD) determination was studied using a novel flow injection analysis (FIA) system with encapsulated
Saccharomyces cerevisiae cells and an oxygen electrode and was compared with conventional 5-day BOD tests. S. cerevisiae cells were packed in a calcium alginate capsule at a dry cell weight of 250 g/l of capsule core. The level of dissolved oxygen
(DO) was reduced due to the enhanced respiratory activity of the microbial cells when the injected nutrient passed through
the bioreactor. The decrease in DO (ΔDO) was intensified with the amount of microbial cells packed in the bioreactor. However,
the specific ΔDO decreased as the amount of cells loaded in the bioreactor increased. The ΔDO value was dependent on the pH
and temperature of the mobile phase and reached its maximum value at 35°C and pH 7–8. Also, ΔDO became larger at longer response
times as the flow rate of the mobile phase decreased. The measurement of ΔDO was repeated more than six times consecutively
using a 20-ppm standard glucose and glutamic acid solution, which confirmed the reproducibility with a standard deviation
of 0.95%. A strong linear correlation between ΔDO and BOD was also observed. The 5-day BOD values of actual water and wastewater
samples were in accordance with the BOD values obtained by this FIA method using encapsulated S. cerevisiae cells. Unlike the cell-immobilized bead system, there was no contamination of the bioreactor resulting from any leak of yeast
cells from the sensor capsules during BOD measurements. 相似文献
3.
Chul-Hong Park Byung Yeoup Chung Seung Sik Lee Hyoung-Woo Bai Jae Young Cho Cheorun Jo Tae Hoon Kim 《Bioorganic & medicinal chemistry letters》2013,23(4):1099-1103
Radiolytic transformation of the isoflavonoid rotenone (1) with γ-irradiation afforded two new degraded products, rotenoisins A (2) and (3). The structures of the two new rotenone derivatives were elucidated on the basis of spectroscopic methods. The new products 2 and 3 exhibited significantly enhanced inhibitory activities against pancreatic lipase and adipocyte differentiation in 3T3-L1 cells when compared to parent rotenone. 相似文献
4.
Sei?Kwang?HahnEmail author Allan?S.?Hoffman 《Biotechnology and Bioprocess Engineering》2004,9(3):179-183
A biocompatible polyelectrolyte complex multilayer (PECML) film consisting of poly-L-lysine (PLL) as a polycation and hyaluronic
acid (HA) as a polyanion was developed to test its use for surface modification to prevent cell attachment and protein drug
delivery. The formation of PECML through the electrostatic interaction of HA and PLL was confirmed by contact angle measurement,
ESCA analysis, and HA content analysis. HA content increased rapidly up to 8 cycles for HA/PLL deposition and then slightly
increased with an increasing number of deposition cycle.In vitro release of PLL in the PECML continued up to 4 days andca. 25% of HA remained on the chitosan-coated cover glass afterin vitro release test for 7 days. From the results, PECML of HA and PLL appeared to be stable for about 4 days. The surface modification
of the chitosan-coated cover glass with PECML resulted in drastically reduced peripheral blood mononuclear cell (PBMC) attachment.
Concerned with its use for protein drug delivery, we confirmed that bovine serum albumin (BSA) as a model protein could be
incorporated into the PECML and its release might be triggered by the degradation of HA with hyaluronidase. 相似文献
5.
Leukotactin-1-induced ERK activation is mediated via Gi/Go protein/PLC/PKC delta/Ras cascades in HOS cells 总被引:1,自引:0,他引:1
Recently cloned leukotactin-1 (Lkn-1) that belongs to CC chemokine family has not been characterized. To understand the intracellular events following Lkn-1 binding to CCR1, we investigated the activities of signaling molecules in response to Lkn-1 in human osteogenic sarcoma cells expressing CCR1. Lkn-1-stimulated cells showed elevated phosphorylation of extracellular signal-related kinases (ERK1/2) with a distinct time course. ERK activation was peaked in 30 min and 12 h showing biphasic activation of ERK. Pertussis toxin, an inhibitor of G(i)/G(o) protein, and phospholipase C (PLC) inhibitor blocked Lkn-1-induced activation of ERK. Protein kinase C delta (PKC delta) specific inhibitor rottlerin inhibited ERK activation in Lkn-1-stimulated cells. The activities of PLC and PKC delta were also enhanced by Lkn-1 stimulation. Dominant negative Ras inhibited activation of ERK. Immediate early response genes such as c-fos and c-myc were induced by Lkn-1 stimulation. Lkn-1 affected the cell cycle progression by cyclin D(3) induction. These results suggest that Lkn-1 activates the ERK pathway by transducing the signal through G(i)/G(o) protein, PLC, PKC delta and Ras, and it may play a role for cell proliferation, differentiation, and regulation of gene expression for other cellular processes. 相似文献
6.
Hack-Lyoung Kim Kwang Nam Jin Jae-Bin Seo Young Ho Choi Woo-Young Chung Sang-Hyun Kim Myung-A Kim Joo-Hee Zo 《PloS one》2015,10(4)
The aim of this study was to investigate whether brachial-ankle pulse wave velocity (baPWV) is associated with the severity of coronary artery disease (CAD) assessed by coronary computed tomography angiography (CCTA), and to evaluate baPWV as a predictor of obstructive CAD on CCTA. A total of 470 patients who underwent both baPWV and CCTA were included. We evaluated stenosis degree and plaque characteristics on CCTA. To estimate the severity of CAD, we calculated the number of segment with plaque (segment involvement score; SIS), stenosis degree-weighted plaque score (segment stenosis score; SSS), and coronary artery calcium score (CACS). The mean baPWV was 1,485 ± 315 cm/s (range, 935-3,175 cm/s). Non-obstructive (stenosis < 50%) and obstructive (stenosis ≥ 50%) CAD was found in 129 patients (27.4%) and 144 (30.6%), respectively. baPWV in patients with obstructive CAD was higher than that of patients with non-obstructive (1,680 ± 396 cm/s versus 1,477 ± 244 cm/s, P < 0.001) or no CAD (1,680 ± 396 cm/s versus ± 196 1,389 cm/s, P < 0.001). baPWV showed significant correlation with SSS (r = 0.429, P < 0.001), SIS (r = 0.395, P < 0.001), CACS (r 0.346, P < 0.001), and the number of segment with non-calcified plaque (r 0.092, P = 0.047), mixed plaque (r = 0.267, P < 0.001), and calcified plaque (r = 0.348, P < 0.001), respectively. The optimal baPWV cut-off value for the detection of obstructive CAD was 1,547 cm/s. baPWV ≥ 1,547 cm/s was independent predictor for the obstructive CAD. In conclusion, baPWV is well correlated with the severity of CAD evaluated by CCTA. baPWV has the potential to predict severity of coronary artery atherosclerosis. 相似文献
7.
Hak Jun Ahn Kang Il Kim Nguyen Ngoc Hoan Churl Ho Kim Eunpyo Moon Kyeong Sook Choi Sang Sik Yang Jong-Soo Lee 《PloS one》2014,9(1)
The plasma jet has been proposed as a novel therapeutic method for cancer. Anticancer activity of plasma has been reported to involve mitochondrial dysfunction. However, what constituents generated by plasma is linked to this anticancer process and its mechanism of action remain unclear. Here, we report that the therapeutic effects of air plasma result from generation of reactive oxygen/nitrogen species (ROS/RNS) including H2O2, Ox, OH−, •O2, NOx, leading to depolarization of mitochondrial membrane potential and mitochondrial ROS accumulation. Simultaneously, ROS/RNS activate c-Jun NH2-terminal kinase (JNK) and p38 kinase. As a consequence, treatment with air plasma jets induces apoptotic death in human cervical cancer HeLa cells. Pretreatment of the cells with antioxidants, JNK and p38 inhibitors, or JNK and p38 siRNA abrogates the depolarization of mitochondrial membrane potential and impairs the air plasma-induced apoptotic cell death, suggesting that the ROS/RNS generated by plasma trigger signaling pathways involving JNK and p38 and promote mitochondrial perturbation, leading to apoptosis. Therefore, administration of air plasma may be a feasible strategy to eliminate cancer cells. 相似文献
8.
Recombinant alkaline phosphatase expressed in insect cells was concentrated 1.5 times by hydrogel ultrafiltration by swelling at 20°C and collapsing at 35°C at 53-65% separation efficiency and 78-83% enzyme recovery. Enzyme entrapment between gel particles and attachment of enzymes to the gel surface was the main reason for the poor separation efficiency and low enzyme recovery. Exposure of the enzyme at the collapse temperature during repeated swelling-collapsing cycles also decreased separation efficiency to 37% due to thermal deactivation of the enzyme. 相似文献
9.
Do Young Kim Han‐Young Cho Hyo Jeong Kim Yi‐Joon Kim Dong‐Ha Shin Kwang‐Hee Son Ho‐Yong Park 《Entomological Research》2011,41(6):297-297
Invertebrates including insects are heterotrophic organisms and widely distributed in ecosystems. Due to their superior ability to digest various types of plant biomass taken as foods, some herbivorous invertebrates have attracted a great deal of industrial attention because such organisms include diverse cellulolytic and hemicellulolytic symbionts in their gut. Recent studies have shown that some of gut microorganisms of herbivores possess one or more extracellular fibrolytic enzymes with unique functions, which can be exploited as useful biocatalysts in various bioindustrial fields. Specifically, microbial hemicellulases with favorable biocatalytic activities are expected to be used for the development of excellent animal feed additives, production of prebiotics such as xylo‐ and mannooligosaccharides, and pretreatment of lignocellulosic biomass for the preparation of fermentable sugars. Here, we review our recent studies accomplished on several hemicellulolytic bacteria isolated from the guts of invertebrates and their glycoside hydrolases such as endo‐β‐1,4‐xylanases and endo‐β‐1,4‐mannanases. 相似文献
10.