• Korean Journal of Pharmacognosy
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• v.17 no.1
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• pp.78-84
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• 1986

Among the Araliaceae plants indigenous to Korea, those whose medicinal usage are comparatively high have been selected in this serial studies. Chiisanoside and acanthoside D were isolated and identified from the Acanthopanax chinensis leaves and root bark. Chiisanoside and acanthoside D have been found to have the lowering S-GPT, S-GOT value and BSP-retention rate and survival rate, anti-histaminic effect in the toxic state through the bio-pharmacological experiments. ${\alpha}-hederin$, hederagenin pentaglycoside were isolated both stem bark of Kalopanax pictum Nakai var. magnificum and Kalopanax pictum Nakai var. Max. respectively. Syringoside, acanthoside D were also isolated from the root bark of Acanthopanax koreanum. The biological activity of ginsenoside $Rb_1$, $Rg_1$, Re were examined. Ginsenoside $Rb_1$, $Rg_1$, Re promotes the antileaking effect in X-ray (Co 60) irradiated toxic state.

• BMB Reports
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• v.35 no.3
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• pp.291-296
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• 2002

Thanatin, a 21-residue peptide, is an inducible insect peptide with a broad range of activity against bacteria and fungi. It has a C-terminal disulfide loop, like the frog skin secretion antimicrobial peptides of the brevinin family. In this study, we tried to find the effect of a number of amino acids between the disulfide bond. Thanatin showed stronger antibacterial activity to Gram negative bacteria than other mutants, except Th1; whereas, the mutant peptides with deletion had higher activity to Gram positive bacteria than thanatin. An increase in the number of amino acid(s) using the alanine residue decreased the antibacterial activity in all of the bacteria. Th1 with deletion of threonine at position 15 ($Thr^{15}$) showed similar antibacterial activity against Gram-negative bacteria, but had higher activity against the Gram positive bacteria. In order to study the structure-function relationship, we measured liposome disruption by the peptides and CD spectra of the peptides. Th1 also showed the highest liposome leaking activity and α-helical propensity in the sodium dodecyl sulfate solution, compared with other peptides. Liposome disruption activity was closely correlated with the anti-Gram positive bacterial activity. All of the peptides showed no hemolytic activity. Th1 was considered to be useful as an antimicrobial peptide with broad spectrum without toxicity.