• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.2
• /
• pp.221-227
• /
• 2011

Applications of green manures generally improve the soil quality in rice paddy in part through restructuring of soil microbial communities. To determine how different green manures affect soil microbial communities during the early stages of rice growth, fatty acid methyl ester (FAME) profiles were used to the effects of different management practices: 1) conventional farming (CF), 2) no-treatment (NT), 3) Chinese milk vetch (CMV), 4) green barley (GB), and 5) triticale in paddy field. With applications of green manures, soil organic matter was significantly higher than CF, while soil Na concentration was significantly lower compared with CF (p<0.05). Total soil microbial biomass of CMV was higher (p<0.05) than NF by approximately 31%. The highest ratio of monounsaturated fatty acid to saturated fatty acid was found in the GB plot, followed by CMV and triticale compared with CF (p<0.05), possibly indicating that microbial stress was less in GB and CMV plots. Populations of Gram-negative bacteria and arbuscular mycorrhizal fungi also were significantly higher green manures than CF (p<0.05). Our findings suggest that GB should be considered as optimum green manure for enhancing soil microbial community at an early growing stage in paddy field.

• Journal of the Korean Chemical Society
• /
• v.26 no.3
• /
• pp.188-193
• /
• 1982

Four new thermotropic copolyesters were prepared and their liquid crystal properties were investigated by differential scanning calorimetry and on a hot-stage of a polarizing microscope. Three copolyesters had same mesogenic unit, triad aromatic ester structure, interconnected through a random combination of either odd-even, or odd-odd, or even-even number of methylene groups in the polymethylene flexible spacers. Another random copolyester consisted of mesogenic units of 1 : 1 mixture of central methyl-and bromohydroquinone moieties with two flanking p-oxybenzoate units connected by decamethylene spacer. All of the polyesters formed nematic liquid crystal phase upon melting. The transitions for melting and nematic ${\to}$ isotropic transformations could be reversibly observed by DSC as well as by microscopic study. The thermodynamic properties for their liquid crystal ${\to}$ isotropic phase transitions were discussed in relation to their chemical structures.

• Natural Product Sciences
• /
• v.25 no.4
• /
• pp.326-333
• /
• 2019

The purpose of our study was to evaluate anti-AD potential of Cirsium maackii flowers. MeOH extract, CH₂Cl₂, EtOAc, and n-BuOH fraction of this flower notably inhibited BACE1 (IC₅₀ = 76.47 ± 1.66, 22.98 ± 1.45, 8.65 ± 0.63, and 72.47 ± 3.04 ㎍/mL, respectively). β-amyrenone (49.70 mg) (1), lupeol acetate (1.43 g) (2), lupeol (1.22 g) (3), lupenone (23.70 mg) (4), β-sitosterol (1.01 g) (6), and β-sitosterol glucoside (13.00 mg) (7) from CH₂Cl₂, apigenin (100.20 mg) (8), luteolin (19.00 mg) (9), apigenin 7-O-glucuronide methyl ester (21.30 mg) (14), and tracheloside (53.70 mg) (5) from EtOAc, apigenin 5-O-glucoside (11.00 mg) (10), luteolin 5-O-glucoside (11.00 mg) (11) and apigenin 7-O-glucuronide (91.00 mg) (12) from n-BuOH, and luteolin 7-O-glucuronide (22.00 mg) (13) from H₂O fraction were isolated. HPLC showed high levels of 8, 9 and 12 in MeOH extract (33.07 ± 0.07, 31. 44 ± 0.17 and 16.89 ± 0.33 mg/g, respectively), EtOAc (161.01 ± 1.78, 96.93 ± 0.34 and 73.38 ± 0.06 mg/g, respectively), and n-BuOH fraction (32.18 ± 0.33, 44.31 ± 0.32 and 105.94 ± 0.36 mg/g, respectively). Since, 3 and 9 are well-known BACE1 inhibitors, the anti-AD activity of C. maackii flower might be attributable to their presence.

• Natural Product Sciences
• /
• v.26 no.2
• /
• pp.144-150
• /
• 2020

Phytochemical investigation of leaves, barks and roots of Nauclea vanderguchtii led to the isolation of sixteen compounds, which includes one citric acid derivative (2), one alkaloid (16), one peptide derivative (3), and twelve triterpenes (1, 4 - 13). These compounds were identified as rotundanonic acid (1), 2-hydroxy-1,2,3-propanetricarboxylic acid 2-methyl ester (2), asperphenamate (3), lupeol (4), stigmasterol (5), betulin (6), betulenic acid (7), stigmasterol 3-O-β-D-glucopyranoside (8), quinovic acid 3β-O-α-L-rhamnoside (9), α-amyrin (10), 3-oxoquinovic acid (11), ursolic acid (12), hederagenin (13), rotundic acid (14), clethric acid (15), and naucleficine (16) by the analysis of their NMR spectroscopic data including 2D NMR spectra and by comparison of their spectroscopic data reported in the literature. Compounds 1 and 3 were isolated for the first time in the genus Nauclea, and compound 2 was isolated for the first time from the Rubiaceae family. Complete NMR assignations for 1 have been published for the first time.

• Journal of Photoscience
• /
• v.6 no.4
• /
• pp.187-191
• /
• 1999

Using fluorescent probe fura-2 acetoxymethyl ester, we studied effects of N-Methyl-D-aspartate (NMDA) on free intracellular $Ca^{2+}$ concentration ([$Ca^{2+}$]$_{i}$) and interaction of ethanol with NMDA-mediated response in freshly dissociated brain cells from newborn rats. Twenty five micromolar NMDA significantly increased ($Ca^{2+}$), and this increasing effect could be prevented or reversed by the NMDA antagonists $Mg^{2}$(1.0 mM) and 2-amino-5-phosphonovalerate (AP5, 100 ${\mu}$M). Ethanol at concentrations from 2.5 to 100 mM inhibited NMDA-mediated calcium current in a concentration-dependent manner. Maximal inhibition of NMDA-mediated calcium current by ethanol was 82% at 50 mM. The ethanol inhibition at 100 mM was not significantly different from the inhibition at 50 mM.

• CELLMED
• /
• v.2 no.4
• /
• pp.38.1-38.6
• /
• 2012

The present study aimed to determine the possible mechanisms of the peripheral antinociception of the aqueous extracts of Dicranopteris linearis (AEDL), Melastoma malabathricum (AEMM) and Bauhinia purpurea (AEBP) leaves in mice. Briefly, the antinociceptive profile of each extract (300, 500, and 1000 mg/kg; subcutaneous (s.c.)), was established using the abdominal constriction test. A single dose (500 mg/kg) of each extract (s.c.) was pre-challenged for 10 min with various pain receptors' antagonists or pain mediators' blockers and 30 min later subjected to the antinociceptive assay to determine the possible mechanism(s) involved. Based on the results obtained, all extracts exerted significant (p < 0.05) antinociceptive activity with dose-dependent activity observed only with the AEMM. Furthermore, the antinociception of AEDL was attenuated by naloxone, atropine, yohimbine and theophylline; AEMM was reversed by yohimbine, theophylline, thioperamide, pindolol, reserpine, and 4-chloro-DL-phenylalanine methyl ester hydrochloride; and of AEBP was inhibited by naloxone, haloperidol, yohimbine and reserpine. In conclusion, the antinociceptive activity of those extracts possibly involved the activation of several pain receptors (i.e. opioids, muscarinic, ${\alpha}_2$-adrenergic and adenosine receptors, adenosine, H3-histaminergic and $5HT_{1A}$, dopaminergic receptors).

• BMB Reports
• /
• v.36 no.4
• /
• pp.373-378
• /
• 2003

Effects of L-arginine and NG-nitro-L-arginine methyl ester (L-NAME) on the renal dysfunction that is induced by cisplatin (CDDP) were investigated. A single dose of CDDP (7.5 mg/kg i.p.) induced renotoxicity, which was manifested by increasing the sensitivity of isolated urinary bladder rings to acetylcholine (ACh), together with a significant elevation of serum urea and creatinine, and a severe decrease in serum albumin. Moreover, renal dysfunction was further confirmed by a significant decrease of enzyme activities, such as glutathione peroxidase, GSH-Px (E.C 1.11.1.9), catalase (E.C 1.11.1.6), as well as a significant increase in lipid peroxides that were measured as malondialdhyde (MDA) in kidney tissue homogenates. The administration of L-arginine (70 mg/kg/d p.o in drinking water 5 d before and 5 d after the CDDP injection) significantly ameliorated the renotoxic effects of CDDP, as judged by restoring the normal responses of isolated bladder rings to Ach, and also by an improvement in a range of renal function indices, which included serum urea and creatinine concentrations and kidney weight. In addition, L-arginine prevents the rise of MDA, as well as a reduction of GSH-Px and catalase activities in kidney tissues homogenates. On the other hand, the administration of L-NAME (4 mg/kg/d p.o) resulted in no protection against renal dysfunction that was induced by CDDP treatment. The findings of this study suggest that L-arginine can attenuate kidney injury that is produced by CDDP treatment. In addition, L-arginine may be a beneficial remedy for CDDP-induced renal toxicity, and could be used to improve the therapeutic index of CDDP.

• Preventive Nutrition and Food Science
• /
• v.4 no.4
• /
• pp.265-269
• /
• 1999

Taurine is a major $\beta$-amino acid in various tissues. Taurine transporter (TAUT) is responsible for the transportation of taurine in the cell. The transporter is affected by various stimuli to maintain its cell volume. Macrophage cell volume varies in its activated states. In our experiment, it was found that the murine macrophage cell line, RAW264.7, expressed TAUT protein in its membrane. Its transportation activities could be blocked by a $\beta$-amino acid such as $\beta$-alanine, but not by $\alpha$-amino acids in this cell line. When assessed in RAW264.7 under the influence of immunosuppressive reagents, the activity of the TAUT was decreased by the treatment of rapamycin (RM) or cyclosporin A (CsA). However when ionomycin (IM) was added to this system, TAUT activity was recovered only in CsA-treated cells in a concentration-dependent manner. In order to inhibit the voltage gated {TEX}$Ca^{+2}${/TEX} channel, calmidazolium was added to the RAW264.7 cell line. Treatment of the cell with calmidazolium completely blocked TAUT. Furthermore, addition of IM to this system recovered the activity of TAUT again. When we added phorbol myristate acetate (PMA) to the cell line, secretion of nitric oxide (NO) was increased 4-fold and the TAUT activity was decreased 5-fold. However, the addition of N-nitro L-arginine methyl ester (L-NAME), an inducible NO synthase (iNOS) inhibitor, to the PMA-treated cells, resulted in the recovery of TAUT activity. These results showed that the activity of TAUT was sensitive to the intracellular concentrations of both {TEX}$Ca^{+2}${/TEX} and NO.

• Herbal Formula Science
• /
• v.17 no.2
• /
• pp.175-186
• /
• 2009

The vasorelaxant effect of an extract of Lophatherum gracile Brongn (ELB) and its possible action mechanism were ascertained in aortic tissues isolated from rats. ELB relaxed endothelium-intact thoracic aorta in a dose-dependent manner. However, the induced vascular relaxation was abolished by removal in endothelium of the thoracic aorta. Pretreatment of endothelium-intact vascular tissues with $N^G$-nitro-L-arginine methyl ester (L-NAME) or 1H-[1,2,4]-oxadiazole-[4,3-$\alpha$]-quinoxalin-1-one (ODQ) significantly inhibited vascular relaxation induced by ELB. Moreover, ELB significantly increased cGMP production in aortic tissues, which was blocked by pretreatment with L-NAME or ODQ. The vasorelaxant effect of ELB was attenuated by tetraethylammonium (TEA), and glibenclamide. ELB-induced vasorelaxation was not blocked by atropine, propranolol, indomethacin, verapamil, and diltiazem. Taken together, the present study demonstrates that ELB dilates vascular smooth muscle via an endothelium-dependent NO-cGMP signaling pathway, which may be at least in part related with the function of $K^+$ channels.

• The Journal of Internal Korean Medicine
• /
• v.27 no.2
• /
• pp.471-479
• /
• 2006

Backgrounds & Objectives: Banhasasimtang granule(BHSST) has been used for the treatment of functional dyspepsia regarded as one of the gastric dysmotility disease. but its mechanisms of action are not well known yet: So we investigated the effects of BHSST on gastric emptying and its mechanisms of action in rats. Methods: Gastric emptying was measured by glass beads(1mm in diameter) expelled from the stomach for 60 min after administration of normal saline(NS) or BHSST 31mg/kg or 93mg/kg in rats. And by the same method gastric emptying was measured after administration of NS or BHSST 93mg/kg in rats treated with atropine sulfate(1mg/kg, s.c.), quinpirol HCI(0.3mg/kg, i.p.), NAME(NG-nitro-L-arginine methyl ester, 75mg/kg, s.c.) or cisplatin(10mg/kg, i.p.) to make delayed gastric emptying. Results: BHSST 93mg/kg improved gastric emptying more than NS or BHSST 31mg/kg(p=0.016). Under the delayed gastric emptying, BHSST 93mg/kg improved gastric emptying in the group treated with NAME$(5.00{\pm}3.101\;vs\;9.00{\pm}3.51,\;p\;=0.046)$, but aggravated it With atropine sulfate$(5.71{\pm}3.45\;vs\;2.57{\pm}1.62,\;p\;=0.050)$ and cisplatin$(12.7{\pm}2.29\;vs\;8.57{\pm}5.06,\;p\;=0.072)$. Conclusions: BHSST improves the gastric emptying through cholinergic and 5-hydroxytryptamine 3 receptors. Especially it is effective to improve gastric emptying delayed by NAME. So we expect that it would be effective in functional dyspepsia with impaired reservoir functions such as gastric adaptive relaxation.