• Proceedings of the Plant Resources Society of Korea Conference
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• 1999.10a
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• pp.46-57
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• 1999

Ginseng(Panax ginseng C.A. Meyer) is important medicinal plant but requires 4-year cultivation for root harvest because of slow growth. In contrast, ginseng callus and hairy roots grow vigorously and may Produce the same or more biologically active compounds for human health than natural ginseng roots. Therefore, ginseng callus and hairy roots can be used for commercial purposes. Polyacetylene, one of anti-cancer compounds in ginseng, was not detected in the callus cultured on the medium containing 2, 4-B, but cells derived from the callus growth was excellent, The ginseng calli cultured on the medium containing 2mg11 CPA and 0.05mg/1 BA was grown vigorously and produced panaxydol, one of ginseng polyacetylene. The biosynthesis of polyacetylene in callus was not affected by addition of NAA and sucrose in media. The SH medium was better than the MS medium for ginseng callus growth and biosynthesis of panaxydol. Another ginseng anti-cancer compounds, ginsenoside-Rg$_3$, Rh$_1$and Rh$_2$ were detected in ginseng hairy roots by heat treatment. Those of Panax ginseng were obtained after root disks of three-year old roots were infected with Agrobacterium rhizogenes Rl000 $A_4$T in dark condition after one month of culture. The optimum growth of hairy roots was achieved in the culture of 1/2 MS liquid medium in dark(22$^{\circ}C$) under 60 rpm gyratory shaking. Hairy roots grew well in 5 ι Erlenmeyer flasks, 1ι roller drums, 10ι jar-fermenters, and especially in 20ι air-lift .culture vessels. All heat treatments had remarkably different ginsenoside contents. Eleven ginsenosides were determined in heat treatment, eight in freeze dried hairy roots. Contents of ginsenoside-Rbl , Rb2, Rc, Rd. Re, Rf, and Rg$_1$tested in all heat treatments were less than those of freeze dried hairy roots. Contents of glnsenoside-Rg$_2$ in heat treatment for 1 hour at 105$^{\circ}C$ was 4.92mg/g dry wt, 3.9 times higher than 1.27 mg/g dry wt of freeze dried hairy roots. The optimum condition of heat treatment for the production of ginsenoside-Rg$_3$and Rhl was 2 hours at 105$^{\circ}C$, and ginsenoside content was 2.58mg/g dry wt and 3.62mg/g dry wt, respectively. The production of ginsenoside-Rh2 was the highest in heat treatment for 2 hours at 105$^{\circ}C$ among treatments examined, and ginsenoside-Rh$_2$content was 1.08mg/g dry wt.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.10a
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• pp.111-124
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• 2003

Processes that cause immobilization of contaminants in soil are of great environmental importance because they may lead to a considerable reduction in the bioavailability of contaminants and they may restrict their leaching into groundwater. Previous investigations demonstrated that pollutants can be bound to soil constituents by either chemical or physical interactions. From an environmental point of view, chemical interactions are preferred, because they frequently lead to the formation of strong covalent bonds that are difficult to disrupt by microbial activity or chemical treatments. Humic substances resulting from lignin decomposition appear to be the major binding ligands involved in the incorporation of contaminants into the soil matrix through stable chemical linkages. Chemical bonds may be formed through oxidative coupling reactions catalyzed either biologically by polyphenol oxidases and peroxidases, or abiotically by certain clays and metal oxides. These naturally occurring processes are believed to result in the detoxification of contaminants. While indigenous enzymes are usually not likely to provide satisfactory decontamination of polluted sites, amending soil with enzymes derived from specific microbial cultures or plant materials may enhance incorporation processes. The catalytic effect of enzymes was evaluated by determining the extent of contaminants binding to humic material, and - whenever possible - by structural analyses of the resulting complexes. Previous research on xenobiotic immobilization was mostly based on the application of $^{14}$ C-labeled contaminants and radiocounting. Several recent studies demonstrated, however, that the evaluation of binding can be better achieved by applying $^{13}$ C-, $^{15}$ N- or $^{19}$ F-labeled xenobiotics in combination with $^{13}$ C-, $^{15}$ N- or $^{19}$ F-NMR spectroscopy. The rationale behind the NMR approach was that any binding-related modification in the initial arrangement of the labeled atoms automatically induced changes in the position of the corresponding signals in the NMR spectra. The delocalization of the signals exhibited a high degree of specificity, indicating whether or not covalent binding had occurred and, if so, what type of covalent bond had been formed. The results obtained confirmed the view that binding of contaminants to soil organic matter has important environmental consequences. In particular, now it is more evident than ever that as a result of binding, (a) the amount of contaminants available to interact with the biota is reduced; (b) the complexed products are less toxic than their parent compounds; and (c) groundwater pollution is reduced because of restricted contaminant mobility.