• Journal of the Korean Society of Tobacco Science
• /
• v.18 no.1
• /
• pp.76-84
• /
• 1996

Flue-cured tobaccos(cv. NC82, grade AB3O-1) expanded by super steam, volatile organic solvents(tricuorofluoromethane, propane), carbon dioxide, nitrogen, and by freeze-drying were examined for their physico-chemical properties. The expanding rate by using the organic solvents or carbon dioxide at the impregnated pressure was 70% or more, whereas the rate by super steam and freeze-drying was 49.4 and 42.9%, respectively. The contents of total sugar, alkaloid and ether extracts of the expanded tobacco by organic solvents or carbondioxide were decreased to 27.6, 20% or more, and 13%, respectively, when compared to non-expanded one. The contents of citric acid of the tobacco expanded by using trichlorofluoromethane and carbon dioxide were increased to 19.1, 14.0%, respectively. Linoleic acid in the tobacco expanded by super steam or trichlorofluoromethane was also increased to 17.3%, but malonic acid in the tobacco expanded by super steam was 18.5% less than that in the non-expanded one. Nineteen essential oil among 22 assayed in this experiment were decreased in the expanded tobaccos. Key words : expanding method, tobacco, physico-chemical properties.

• Journal of the Korean Society of Tobacco Science
• /
• v.22 no.2
• /
• pp.143-150
• /
• 2000

This study was carried out to investigate the effect of storage period on the physico-chemical properties of tobacco leaves expanded by $CO_2$. The flue-cured and burley tobacco leaves produced from 1996 to 1999 were processed, and stored for that year or 3 years in processing plant. As compared with 1996 crop, the expanded rate of flue-cured tobacco leaves in 1999 crop was higher approximately 18%, while that of burley was higher about 10%. The filling capacity of cigarettes was decreased as storage time became shorter, but the combustibility was improved. The rate of large particles (over 3.36mm) of expanded tobacco showed decreasing tendency as the storage period became longer. The change rate of chemical contents in tobacco leaves between before and after expansion had no significant difference among corp years. The tar and CO contents of cigarettes smoke were reduced in the case of flue-cured tobacco leaves as storage time became shorter, while they were slightly increased in the case of burley tobacco leaves. The ammonia content of burley leaves was decreased remarkably in 1996 and 1999 crop.

• Journal of the Korean Society of Tobacco Science
• /
• v.21 no.2
• /
• pp.144-151
• /
• 1999

This study was carried out to compare the change physico-chemical properties in the 10 grades of Burley leaf tobacco expanded by $CO_2$. The filling capacity of AB3T was increased from 5.44cc/g to 9.52cc/g with the expansion rate 75.0% and that of CD3W was increased from 5.57cc/g to 10.16cc/g with the expansion rate 82.4%. But the rate of cut tobacco longer than 3.36 mm decreased from 77.2% to 49.9% and from 67.3% to 41.2% in grade B1T and C1W, respectively. The contents of nicotine and total volatile base in the of expanded cut tobacco decreased 11.9% and 10.4% respectively. The contents of onganic acids, except oxalic and palmitic acid, essential oil, amino acids, nicotine, tar and ammonia contents in the cigarette smoke decreased by expansion procecs. These results suggest that expanded tobacco was very useful to make less irritative cigarettes.

• Journal of Microbiology and Biotechnology
• /
• v.4 no.4
• /
• pp.349-353
• /
• 1994

An isolate 90-GT-302, identified as Kitasatosporia kimorexae, was found to produce antibiotics that induce mycelial swelling in Magnaporthe grisea, and Fusarium solani. The strain produced at least 5 antibiotics. Among them, the main active compound designated as kimorexin A was isolated and its physico-chemical properties and biological activities were examined, and as a result was found to be of the thiopeptide antibiotic. A comparison between the properties of kimorexin A and those of the known thiopeptide antibiotics led us to conclude that kimorexin A was a new thiopeptide polythiazolyl antibiotic. Kimorexin A showed a narrow antimicrobial spectrum against very limited genus of phytopathogenic fungi. It prevented host plants from infections of Rhizoctonia solani and absolute parasitic fungi, such as Sphaerotheca fuliginea and Puccinia recondita, almost completely at the treatment concentration of approximately 20 ppm.

• Journal of the Korean Society of Tobacco Science
• /
• v.22 no.2
• /
• pp.133-137
• /
• 2000

The bulk curing experiment to improve the quality of flue-cured leaves were carried out to evaluate relationship between the modified(3 step-up) drying and conventional drying method in bulk curing process. Modified drying method was somewhat higher values in yellowing color index of cured leaves, and less brittle than those in conventional drying program. As to the chemical properties, there was no difference in chemical component levels in cured leaves between the modified and the conventional methods, while the major chemical compounds in relation to aromatic essential oil of cured leaves showed mostly higher level in the modified method than that in conventional drying method. Additionally 3 step-up drying method increased the tobacco quality by 2 % in price per kg compared with conventional drying method.

• Proceedings of the Korean Society of Tobacco Science Conference
• /
• 1998.05a
• /
• pp.27-27
• /
• 1998

• Proceedings of the Korean Society of Tobacco Science Conference
• /
• 2000.05a
• /
• pp.27-27
• /
• 2000

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.2
• /
• pp.200-206
• /
• 1996

Experiment was conducted to get the information about physico-chemical properties of flue-cured tobacco on the degree of maturity cultivated in paddy-upland rotated field, and compared to upland ones. For the samples of this experiment, 3~4 leaves at each stalk position were harvested from the bottom of plants. Physico-chemical properties of cured leaves were determined from the samples collected at weekly intervals, and of obtained from 4 stalk positions. For the degree of maturity, harvested leaves were separated with visual characters into four classes such as immature, mature, ripe, and mellow. Regardless of stalk position, the order of shrinkage rate with length and width of leaves was mellow> immature> ripe> mature, and ripe leaves from paddy field showed higher shrinkage rate than those of upland. Nicotine and total nitrogen contents were decreased with the degree of maturity while reducing sugar content were showed a reverse tendency. Ripe leaves from paddy field had lower reducing sugar contents, comparing with upland tobacco. Filling capacity of cured leaves from paddy field was decreased with degree of maturity, but there was no difference between upland and paddy tobacco. Shatter index was increased in the oeder of immature > mellow > mature > ripe. Chemical components of cigarette smoke from paddy field tobacco were little higher in $CO_2$ total particulate matter and tar contents, while combustibility was little lower than that of upland tobacco. It was also evaluated that paddy field tobacco was unfavorable for the non-volatile organic and higher fatty acids contents comparing with upland tobacco.

• Journal of the Korean Society of Tobacco Science
• /
• v.17 no.2
• /
• pp.103-108
• /
• 1995

Antibiotic and physico-chemical properties of an active compound from actinomycetes isolate G-37, of which the culture filtrate had an inhibitory effect against tobacco mosaic virus(W) infection, were examined. The active compound, which was purified by ethylacetate extraction, silica gel column chromatography, preparative thin layer chromatography, and high performance liquid chromatography, showed strong antibacterial activities especially against Gram-positive bacteria including Bacillus subtillis, Sarcina lutea and Staphylococcus aureus. From the IH-NMR, FAB/RfS, UV spectral data, and physicochemical properties, the active compound of G-37 appears to belong to a peptide antibiotic group. Among the known peptide antibiotics in the antibiotic group, No. 280, A-30912, and Taitomycin showed molecular weights and ultra violet spectrum similar to those of the active compound from G-37, but was not identical to the compound, which suggests that it may be a new peptide antibiotics.

• Journal of the Korean Society of Tobacco Science
• /
• v.20 no.2
• /
• pp.139-143
• /
• 1998

The occurrence and physico-chemical properties of flat leaves found in 1997 curing trial related to the prevention of occurrence of flat leaves at bulk curing of flue-cured tobacco were investigated and compared with those of normal leaves. Cured leaves of NC82 were separated into 4 classes of none, slight, fair and severe symptoms of flat leaf by the percentage of flattened parts to whole leaf area. The flat leaves were mostly found among the leaves of lower stalk position, and it was estimated that growth rate of lower leaves also influenced on the occurrence of flat leaves. In chromatic aberration of cured leaf, flat leaves showed remarkably lower b and L values than in those of normals but there was no difference in a value. On the other hand, in chemical analyses of flat leaf samples, nicotine, total sugar, ether extract and total nitrogen contents were decreased with the degree of flat symptoms. In physical properties, filling capacity of cured leaves was decreased with the degree of flat symptoms comparing with those of normal leaves, while shatter index was showed a reverse tendency, and then within the same leaf, flat parts were decreased in total sugar, ether extract and filling capacity compared with those of normal ones, but remarkably increased in shatter index, and there was no difference in nicotine and total nitrogen contents.