ABSTRACT
Common primers which amplify the 3' terminal genomic RNAs of Allium carlaviruses were designed based on the nucleotide sequence of shallot latent virus (SLV), garlic latent virus (GLV) and garlic common latent virus (GCLV). A total of fifteen cDNAs encoding the coat protein (CP) of the carlaviruses, including the biologically identified isolates SLV, GLV and GCLV as well as viruses from infected Allium plants cultivated in different parts of the world, were amplified by RT-PCR with the common primers. The cDNAs were then cloned and sequenced. The predicted viral CP amino acid sequence as well as the nucleotide sequence revealed that SLV and GLV, previously considered as separate viruses on the basis of their biological and physical properties, belong to the same species of the genus Carlavirus. Both viruses are clearly differentiated from GCLV. In addition, every SLV and GLV isolate from the Allium plants in Taiwan showed characteristic and common variations in their CP sequences, suggesting the possible presence of geographical variants. However, no apparent sequence variations of SLV and GLV related to their host plant species, including A. sativum, A. wakegi, A. chinense, A. fistulosum, A. cepa and A. ampeloprasum, were observed. These findings suggested that the sequence variations observed in the respective virus isolates do not correlate with the specificity of their infectivities for Allium species.
Subject(s)
Allium/virology , Capsid/chemistry , Carlavirus/classification , Amino Acid Sequence , Carlavirus/chemistry , Molecular Sequence Data , Polymerase Chain ReactionABSTRACT
The pharmacological properties of seven pure saponins isolated from Panax ginseng C. A. Meyer were studied. 1. The ginseng saponins showed weak toxicities in mice. Especially, Rg1, Rf and Rb 1, which contained glucose as a sugar component, were weaker in their toxicities than the rest, which contained arabinose and/or rhamnose. It was also noted that the saponins containing protopanaxadiol as sapogenin were more toxic than those containing protopanaxatriol. 2. All the saponins diminished ACh-induced contraction of the isolated ileum of the guinea pig. On the other hand high concentrations of Rb 2 caused contraction of the ileum by itself. 3. All of the saponins induced a decrease in heart rate and showed biphasic actions on the blood pressure in rats, while they little affected respiration. They caused blood pressure fall preceded by slight rise. Among them, Rg 1 showed the most prominent action and it produced a blood pressure rise with doses of 30 to 100 mg/kg. The pressor as well as depressor action was not influenced by the pretreatment with any of atropine, diphenhydramine, phentolamine and propranolol. 4. Rg 1 and Re showed vasodilator action in dogs, the potencies of which were 1/20 and 1/50 of that of papaverine, respectively. Rc and Rb 2 showed very weak vasodilator actions but Rb 1 did not. 5. Among the 7 saponins, Rd, Re and Rb 2 showed more potent hemolytic actions than those of the rest and the potencies were proportional to their toxicities. 6. Whereas single administration of Rf, Re and Rd significantly suppressed the conditioned avoidance response, repeated administration of them caused facilitation of the response. On the other hand, Rb 2 always showed very weak suppressant action. 7. Rg 1, Rf, Re and Rd significantly suppressed the fighting of mice induced by foot shock, while Rb 1, Rb 2 and Re little affected the fighting. 8. All the saponins showed antifatigue action. They markedly increased the movement after compulsory gait and the action was consistent and independent of their action on the movement before compulsory gait. 9. The saponins showed moderate depressant actions on the EEG and the behavior in cats. They were qualitatively similar in their actions, although Rg 1, Re and Rb 2 were more potent than the rest. They also suppressed EEG arousal response induced by electrical stimulation of the mid brain in cats.
Subject(s)
Panax , Plants, Medicinal , Saponins/pharmacology , Acetylcholine/antagonists & inhibitors , Aggression/drug effects , Animals , Arousal/drug effects , Avoidance Learning/drug effects , Blood Pressure/drug effects , Cats , Conditioning, Psychological/drug effects , Dogs , Electroencephalography , Female , Femoral Artery/drug effects , Guinea Pigs , Heart Rate/drug effects , Hemolysis/drug effects , Histamine H1 Antagonists/pharmacology , Humans , Ileum/drug effects , Lethal Dose 50 , Male , Mice , Mice, Inbred Strains , Motor Activity/drug effects , Muscle Contraction/drug effects , Muscle, Smooth/drug effects , Rats , Regional Blood Flow/drug effects , Respiration/drug effects , Saponins/toxicityABSTRACT
For the purpose of clarification of pharmacological actions of ginseng saponins we tried the isolation of ginseng saponins on a larger scale and succeeded in the isolation of eight saponins in a pure state and in sufficient amounts for the pharmacological assay. These eight saponins agreed all completely with the authentic samples of Shibata-Shoji and co-workers in molecular formula of saponins and sapogenins, sugars and TLC. The physical properties of saponins were shown. As other components of ginseng, there were isolated small amounts of panaxadiol, panaxatriol, daucosterol from the first running of column chromatography and mannitol, sucrose and glucose from the ethanol insoluble aqueous extract.
