• Journal of Plant Biology
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• 제31권2호
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• pp.155-164
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• 1988

The rapid senescence of detached Chinese cabbage leaf discs in darkness is first manifested by a sharp rise in malondialdehyde content (indicated by distruption of membrane structure), then by a rise in peroxidase activity and a decrease in catalase activity, and ultimately by chlorophyll degradation. These changes in parameters besides the catalase activity during senescence were delayed by application of spermidine. Especially, 10-4M spermidine almost completely arrested chlorophyll degradation after incubaton over 5 days. Spermidine reduced the amount of ethylene produced by senescing leaf discs. Additionally, it also reduced IAA-induced ethylene production. Calcium ion (1mM, 10mM) supplied together with the spermidine diminished the spermidine action, indicating probable involvement of an initial ionic attachment mechanism. These results suggest that spermidine can be used as an anti-senescence agent for plants and that this agent may stabilize membrane structure through interaction with the negatively charged loci on the membrane and exert the influence during senescence.

• 생약학회지
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• 제44권2호
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• pp.161-167
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• 2013

Aldose reductase (AR) has been shown to play an important role in the development of the diabetic complications. To discover novel treatments for diabetic complications from natural sources, 59 Chinese herbal medicines have been investigated for inhibitory activities on AR. Among them, 10 herbal medicines, Catalpa fargesii (stem and leaf), Saussurea Laniceps(whole plant), Alnus nepalensis(stem and leaf), Swertia macrosperma (whole plant), Woodfordia fruticosa (stem and leaf), Elsholtzia bodinieri (whole plant), Elsholtzia fruticosa (whole plant), Rosa multiflora (fruit), Nardostachys chinensis (whole plant), Eurya groffii (stem and leaf) exhibited a significant inhibitory activity compared with 3,3-tetramethyleneglutaric acid (TMG) as positive control. Particularly, 4 herbal medicines, C. fargesii (stem and leaf), S. Laniceps (whole plant), A. nepalensis (stem and leaf), S. macrosperma (whole plant) showed two times more potent inhibitory activity than TMG ($5.37{\mu}g/ml$).

• Journal of Life Science
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• 제11권1호
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• pp.14-21
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• 2001

To investigate the changes of carbohydrate metabolism in the senescing leaves of Zea mays during dark-induced senescence, the changes in the contents of reducing sugar, sucrose and starch as well as the activities of sucrose synthase, three isozymes of invertase, and ${\alpha}$-amylase were measured. In the senescing leaves, the content of reducing sugars temporarily increased at 4 d and rapidly decreased thereafter, whereas sucrose contents gradually decreased thereafter, whereas sucrose contents gradually decreased until 3 d of senscence and significantly decreased thereafter. The activities of intracellular invertases such as soluble acid and alkaline formed gradually enhanced until 4 d of leaf senescence and significantly declined thereafter. The extracellular invertase activity showed no significant changes during leaf senescence. The deactivation of sucrose synthase was observed within 3 d of leaf senscence. On the other hand, the starch contents gradually declined during 2 d of leaf senescence, and showed a temporary increase at 3 d, which is similar to the pattern of sucrose synthase activity., These results imply that sucrose in the senescing leaves. The major enzymes which correlated to the breakdown of sucrose during dark-induced senescence were soluble acid and alkaline invertases, not sucrose and ABA accelerated leaf senescence by inducing the accumulation of reducing sugar. These result, therefore, that leaf senescence may be mediated by the temporary quantitative changes of reducing sugar induced by the activation of intracellualr inveertases.

• The Plant Pathology Journal
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• 제17권5호
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• pp.249-256
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• 2001

Xanthomonas axonopodis pv. glycines 8ra produces a bacteriocin called glycinecinA, which specifically inhibits the growth of bacteria belonging to Xanthomonas species. GlycinecinA was produced by culturing Escherichia coli DH5 containing biosynthetic genes for glycinecinA, and was tested for its control effect against X. vesicatoria on red pepper and X. oryzae pv. oryzae on rice. The bacteriocin activity was much higher in the cell extract than in the supernatant. It reached a maximum level at the stationary phase, ws maintained up to 2 months at room temperature and approximately 10 months at $4^{\circ}$. The optimum concentration of glycinecinA for the control in the greenhouse and in the field was 12,800 AU/ml. In this study, the activity of glycinecinA on rice and red pepper leaves continued for 7-8 days, during which the pathogen populations remained at low levels. Bacterial leaf spot of red pepper and bacterial leaf blight of rice were significantly reduced by the bacteriocin treatments. The control efficacy was as high as, or even higher than, the chemical treatment of copper hydroxide. These results suggest that the bacteriocin is a potential control agent for bacterial diseases.

• 생약학회지
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• 제42권4호
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• pp.371-378
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• 2011

Aldose reductase (AR) has been implicated in the development of the diabetic complications. To discover novel treatments for diabetic complications from natural sources, 65 Korean herbal medicines have been investigated for inhibitory activities on AR. Of these, 23 herbal medicines exhibited a significant inhibitory activity compared with 3,3-tetramethyleneglutaric acid (TMG). Particularly, 8 herbal medicines, Acer tataricum (twig, stem and leaf), Acer tataricum (fruit), Rhododendron schlippenbachii (twig, stem and leaf), Weigela subsessilis (twig, stem and leaf), Acer mono (branch and leaf), Ailanthus altissima (twig, stem and leaf), Lindera obtusiloba (branch and leaf), Solidago serotina (whole plant) showed three times more potent inhibitory activity than the positive control, TMG.

• 한국환경보건학회지
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• 제45권5호
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• pp.520-528
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• 2019

Objectives: This study assessed the cytotoxicity of the metallic mordant cupric acetate (CA) and the protective effect of Albizzia julibrissin (AJ) leaf extract on CA-induced cytotoxicity in NIH3T3 fibroblasts. Methods: For this study, cell viability and antioxidative effects such as the inhibitory activity of lipid peroxidation (LP) and superoxide anion-radical (SAR) scavenging activity were assessed. Results: CA significantly decreased cell viability in a dose-dependent manner, and the $XTT_{50}$ value was measured as $55.0{\mu}M$ of CA. The cytotoxicity of CA was determined as highly toxic by Borenfreund and Puerner's toxic criteria. The catalase antioxidant significantly increased cell viability diminished by CA-induced cytotoxicity in these cultures. Regarding the protective effect of AJ leaf extract on CA-induced cytotoxicity, AJ leaf extract remarkably increased the SAR scavenging ability and the inhibitory ability of LP. From these findings, it is suggested that oxidative stress is involved in the cytotoxicity of CA, and AJ leaf extract effectively protected CA-induced cytotoxicity via antioxidative effects. Conclusions: Natural resources like AJ leaf extract may be a putative therapeutic agent for treatment or alleviation of the toxicity induced by CA metallic mordant.

• 한국식품조리과학회지
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• 제22권4호통권94호
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• pp.468-476
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• 2006

The objectives of this study were to determine the antioxidant and cytotoxic activities of Zelkova leaf extract and the sensory and textural characteristics of Zelkova leaf rice cake. The ethyl acetate layer of Zelkova leaf extract showed the most effective DPPH radical and superoxide anion scavenging activities. The residual layer of Zelkova leaf extract exhibited potent cytotoxicity against the HeLa cell line. In the sensory evaluation, the color and taste of Zelkova leaf rice cakes were not significantly different. Zelkova leaf rice cakes with 20%(5.18), 25%(4.94) and 30%(4.88) added Zelkova leaves showed higher overall acceptability than 0%(4.06) added Zelkova leaves. In the textural analysis, the hardness of the Zelkova leaf rice cake increased slowly with increasing leaf content during 3 day storage. The cohesiveness of 25% and 30% Zelkova leaf rice cakes showed no variation with storage time but that of 0% Zelkova leaf rice cakes decreased with increasing storage period. The 'L' value of Zelkova leaf rice cake decreased with increasing leaf content while the 'a' value of 0% Zelkova leaf rice cake was lower than that of 20%, 25% and 30% Zelkova leaf rice cakes.

• 한국식생활문화학회지
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• 제9권2호
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• pp.137-142
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• 1994

돌산갓의 독특한 향미와 잠재된 항균성을 김치의 맛과 저장성 향상에 이용하기 위한 기초자료로서 갓의 myrosinase를 분리 정제하여 그 특성을 밝히고, 갓김치 숙성 중 myrosinase 활성도 변화를 측정하였다. 갓의 myrosinase를 DEAE Sephadex, chromatofocusing 및 Con A Sepharose column chromatography에 의해 정제한 결과 비활성은 7107배 증가하였고 수율은 18.8%였다. 정제된 효소의 최적 pH는 5.9였으며, 등전점은 4.6, 분자량은 약 129 kD, Km은 0.206 mM, Vmax는 $2.039\;{\mu}M{\cdot}min^{-1}{\cdot}mg\;protein^{-1}$로 나타났다. 또한 myrosinase의 activator인 ascorbic acid는 0.6 mM에서 최대 효소활성을 보이다가 그 이후는 점차 효소활성의 감소를 보여 2.0 mM 이상의 농도에서는 효소활성을 거의 완전히 상실시켰다. 갓김치의 저장 중 myrosinase 활성 변화를 측정한 결과 김치 제조 직후에 약 70 nmol/min/mg protein이던 것이 $20^{\circ}C$에서 3일 이상 저장으로 급격히 그 활성을 잃어 4일 후에는 50% 이상의 활성을 손실하고 10일 후에는 거의 활성이 없었다.

• Preventive Nutrition and Food Science
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• 제22권3호
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• pp.191-194
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• 2017

Ocimum gratissimum is a common plant in the tropics and has been used in food and medicine. Its usage in food and medicine could be attributed to its phtyochemical and antimicrobial properties. In this study we investigated the proximate, phytochemical, and antimicrobial attributes of air dried leaves of O. gratissimum. The aqueous extract was found to contain phtyochemicals with alkaloid and saponin present in appreciable amounts. The proximate analysis (crude protein and crude fibre content were 15.075% and 17.365%, respectively) showed that the leaf could be a good source of protein and fibre. The aqueous ethanolic extract of the leaf exhibited activity against a wider range of organisms when compared to the aqueous extract at the investigated concentrations. Aqueous ethanolic extracts of O. gratissimum leaf was active against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus cereus and the aqueous extract of the leaf was active against P. aeruginosa.

• Journal of Plant Biology
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• 제36권4호
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• pp.307-312
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• 1993

In germinating pea, contents of enodgenous polyamine in the leaf and stem were determined, and protein content, peroxidase activity and pattern of isozymes were examined in the leaf treated with polyamines. During growth of the pea for 14 days in light condition, the polyamines in leaf and stem showed the highest level at the 5th day, and were decreased rapidly at the 7th day, kept almost constant level since then. The putrescine level was relatively higher than those of spermidine and spermine, and cadaverine was also detected. On the other hand, in the leaf treated with spermine (0.01 mM) protein content increased about 250% than that of the control, the peroxidase activity increased ore than 100% in spermine of 0.01 mM and 0.1 mM. In treating with putrescine of 0.1 mM the pattern of peroxidase isozyme appeared 4 new cathodic bands (pI 4.8, 5.6, 5.9 and 6.8) compared with the control, the clear cathodic bands (pI 5.6, 5.9, 6.4 and 6.6) were also observed in spermine of 0.1 mM. These results suggest that polyamines were important factor in the differentiation of pea at the early stage of germination.