• Journal of the Korean Society of Tobacco Science
• /
• v.29 no.2
• /
• pp.74-79
• /
• 2007

This study was conducted to evaluate the prediction of sensory property of smoke from leaf chemical property and characterize leaf chemical components for the best tobacco taste's leaves in flue-cured tobacco. For analytical and sensory evaluations, one hundred and forty grades were used. The major leaf chemical components to predict the sensory property of smoke were nicotine for impact, irritation and off taste & odor, and total sugar/nicotine ratio for tobacco taste. Within ${\pm}20%$ range of difference, the predictable probabilities of sensory property of smoke form leaf chemical property were 80.0% for off taste & odor and $91.4{\sim}96.4%$ for impact, irritation and tobacco taste. As a result of K-means cluster analysis on the basis of tobacco taste, the desirable leaf chemical component contents were $2.77{\sim}3.55%$ in nicotine and $5.1{\sim}6.9$ in total sugar/nicotine ratio. This study suggest that the some regression equations may be useful to predict the sensory property of tobacco smoke from a few selected leaf chemical components in flue-cured tobacco and to select the flue-cured tobacco leaves for enhance the tobacco taste of cigarette.

• 한국생물공학회:학술대회논문집
• /
• 2003.10a
• /
• pp.563-566
• /
• 2003

This study was proposed to measure total polyphenols and antioxidant activities from leaves of Stachys sieboldii MIQ. Solvents such as acetone 60%, petroleum ether, ethylacetate, and water were used for this purpose The fraction by ethyl acetate fraction showed the strongest activity by DPPH method and contained much more polyphenols than those by other solvents.

• Natural Product Sciences
• /
• v.12 no.3
• /
• pp.119-121
• /
• 2006

Four 3,4-seco-lupane trierpenoids were isolated from the MeOH extract of the leaves of Acanthopanax divaricatus forma flavi-flos Yook by using various column chromatography. The chemical structures of isolates were identified as chiisanogenin, chiisanoside, isochiisanoside and 11-deoxyisochiisanoside on the basis of physico-chemical and spectroscopic date($^1H-NMR,\;^{13}C-NMR$M$, 2D-NMR and FAB-MS). These compounds were isolated for the first time from A. divaricatus forma flavi-flos.

• Korean Journal of Pharmacognosy
• /
• v.47 no.2
• /
• pp.117-121
• /
• 2016

Two flavonoid glycosides and three secoiridoide glycosides were isolated from the leaves of Lonicera maackii. On the basis of spectral and physico-chemical data, the structures of isolated compounds were identified as hesperetin-7-O-glucoside (1), luteolin-7-O-${\beta}$-D-glucopyranoside (2), secologanin dimethylacetal (3), epi-vogeloside (4), and vogeloside (5), respectively. Hesperetin-7-O-glucoside (1) was isolated for the first time from this plant.

• Journal of the Korean Society of Tobacco Science
• /
• v.5 no.1
• /
• pp.35-42
• /
• 1983

This study was conducted to know changes in chemical components and some enzyme activity on tobacco leaves of NC2326 and Hyangchio (Nicotiana tabacum L. ) by different curing methods. The activity of $\alpha$, $\beta$-amylase and invertase of flue-cured tobacco variety NC2326 were higher than that of sun-cured variety Hyangchio. And the peak of all of enzyme activity in both varieties showed at about 60 hours (at color fixing stage) and 6 days (yellowing stage) after start of flue-curing and sun-curing, respectively. The peak time of reducing sugar content were same with the maximum enzyme activity during curing process in both varieties. During both curing process, the content of starch was greatly reduced and there was a corresponding increase in reducing sugars. Increase in total alkaloids content continued during flue-curing process in both varieties, but during sun-curing process total alkaloids content of NC 2326 were Increased whereas those of Hyangchio were decreased markedly.

• Journal of the Korean Society of Tobacco Science
• /
• v.8 no.1
• /
• pp.41-48
• /
• 1986

This experiment was carries out to study on the effect of temperature raising rate to chemical composition of tobacco leaves during the midrib drying stage of flue-curing. The results were as follows : In the case of the temperature raising rate became more rapidly during midrib drying stage. It had a tendency to increase in oxailic acid, succinlc acid, ammonia, polyphenol; there was a large loss of total sugar, reducing sugar, malic acid, palmitic acid and linolenic acid; leaf color became more reddish; the leaf quality index value decreased, thereby the quality of external appearance deteriorated. It is desirable that the temperature raising rate had to be more slowly.

• Archives of Pharmacal Research
• /
• v.25 no.4
• /
• pp.438-440
• /
• 2002

A new unsaturated hydroxy fatty acid was isolated from the leaves of Cucurbita moschata through repeated silica gel column chromatography and chemical methods. The structure of the new fatty acid was determined as 13-hydroxy-9, 11, 15-octadecatrienoic acid on the basis of several spectral data including 2D-NMR. The stererostructures of double bonds were determined to be 9Z, 11 E and 15E by coupling patterns of related proton signals in the $^1H-NMR$ and NOESY experiments.

• Journal of the Korean Society of Tobacco Science
• /
• v.3 no.1
• /
• pp.66-74
• /
• 1981

This study was conducted to investigate the interaction between chemical compositions and agronomic characteristics of perique tobacco leaf. At the topping stage, the thickness of leaf was positively correlated with total sugar($\textrm{0.975}^{**}$), reducing sugar($\textrm{0.975}^{**}$), alkaloid($\textrm{0.518}^{*}$) and petroleum ether extract($\textrm{0.801}^{**}$) contents. The length of upper leaf was negatively correlated with its chemical contents. Total sugar contents of the harvested leaf showed a sigmoid pattern of distribution along the leaf stalk positions.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.7
• /
• pp.2151-2154
• /
• 2014

• Korean journal of applied entomology
• /
• v.41 no.1
• /
• pp.67-73
• /
• 2002

Studies were conducted to investigate the control effects of several insecticides on Apolygus(=Lygocoris) spinolae(Meyer-Dur) and to develop its management strategies in grapevine yards. Of insecticides which were applied by farmers in commercial grapevine yards, chlorpyrifos, parathion, fenvalerate, and esfenvalerate$.$fenitrothion showed good control effects against A. spinolae. In designed field experiments of fenitrothion and chlorpyrifos for the evaluation of A. spinolae control, both insecticides showed high control efficacy of 94.8 and 91.6%, respectively. The damage of A. spinolae was examined in a grapevine yard, where five different combinations of application timing and number were treated with fenitrothion to assess yield losses (average cluster weight) by A. spinolae. There were no significant differences among average cluster weights of sprayed vines; 466.0 g in sprayed vines on 2 to 3 leaves unfolded stage, 460.7g in sprayed vines on flower separating stage, 465.0 g in sprayed vines each on 2 to 3 leaves unfolded and flowers separating stage, and 487.4 g in sprayed vines each on 2 to 3 leaves unfolded, flowers separating and fruit set stage. Weights of fruit clusters of unsprayed vines was significantly lower than those of sprayed vines. Based on yield and spray cost, chemical control on 2 to 3 leaves unfolded stage produced higher net income than each spray on 2 to 3 leaves unfolded and flower separating stage (i.e., two times of spray), and produced similar net income as each spray on 2 to 3 leaves unfolded, flowers separating and fruit set stage (i.e., three times of spray). Thus, the 2 to 3 leaves unfolded stage was economical spray timing to controlA. spinolae in grapevine yards. Also, management strategies for A. spinolae were discussed.