Wataru Sugiura

Bio: Wataru Sugiura is an academic researcher from Kindai University. The author has contributed to research in topics: Furylfuramide & Ames test. The author has an hindex of 4, co-authored 4 publications receiving 76 citations.

Moscatilin from Dendrobium nobile, a Naturally Occurring Bibenzyl Compound with Potential Antimutagenic Activity

Abstract: A bibenzyl compound that possesses antimutagenic activity was isolated from the storage stem of Dendrobium nobile. The isolated compound suppressed the expression of the umu gene following the induction of SOS response in Salmonella typhimurium TA1535/pSK1002 that have been treated with various mutagens. The suppressive compound was mainly localized in the n-hexane extract fraction of the processed D. nobile. This n-hexane fraction was further fractionated by silica gel column chromatography, which resulted in the purification and subsequent identification of the suppressive compound. EI-MS and (1)H and (13)C NMR spectroscopy were then used to delineate the structure of the compound that confers the observed antimutagenic activity. Comparison of the obtained spectrum with that found in the literature indicated that moscatilin is the secondary suppressive compound. When using 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide) as the mutagen, moscatilin suppressed 85% of the umu gene expression compared to the controls at <0.73 micromol/mL, with an ID(50) value of 0.41 micromol/mL. Additionally, moscatilin was tested for its ability to suppress the mutagenic activity of other well-known mutagens such as 4-nitroquinoline-1-oxide (4NQO), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), UV irradiation, 3-amino-1,4-dimethyl-5H-pyrido[4,3b]indole (Trp-P-1), benzo[a]pyrene (B[a]P), and aflatoxin B(1) (AFB(1)). With all of the aforementioned chemicals or treatments, moscatilin showed a dramatic reduction in their mutagenic potential. Interestingly, moscatilin almost completely suppressed (97%) the AFB(1)-induced SOS response at concentrations <0.73 micromol/mL, with an ID(50) of 0.08 micromol/mL. Finally, the antimutagenic activities of moscatilin against furylfuramide and Trp-P-1 were assayed by the Ames test using the S. typhimurium TA100 strain. The results those experiments indicated that moscatilin demonstrated a dramatic suppression of the mutagenicity of only Trp-P-1 but not furylfuramide.

Suppression of furylfuramide-induced SOS response by acetophenones using Salmonella typhimurium TA1535/pSK1002 umu test.

Abstract: The recently isolated paeonol (2-hydroxy-4-methoxyacetophenone), as one of the antimutagenic compounds from Discorea japonica, was used as a lead compound for detailed structure−activity relationship studies. Nine acetophenones (2-hydroxy-4-methoxy, 2-hydroxy-5-methoxy, 2-hydroxy-6-methoxy, 4-hydroxy-3-methoxy, o-methoxy, m-methoxy, p-methoxy, and 2,5-dimethoxyacetophenone and acetophenone) were investigated for their ability of suppression of furylfuramide-induced SOS response using Salmonella typhimurium TA1535/pSK1002 in the umu test, against the mutagen, 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide). The results showed that 2-hydroxy-6-methoxyacetophenone displayed the strongest activity (EC50 = 0.6 μmol/mL), and a hydroxyl group at C-2 is necessary feature for acetophenone derivatives to show the suppressive effects of furylfuramide-induced SOS response. Keywords: Acetophenones; suppressive effects; SOS response; umu gene; Salmonella typhimurium TA1535/pSK1002; furylfuramide

Reduction of oxazepam to desmethyldiazepam by human intestinal bacteria.

Abstract: The biotransformation of oxazepam by Bifidobacterium bifidum was studied. The major metabolite was purified by chromatographic methods and found to be desmethyldiazepam using NMR, IR and other physicochemical data.

[The SOS-inhibition activity of human urine investigated by umu-test--diurnal and daily changes of SOS-inhibition activity of urine].

Abstract: We found that human urine suppressed SOS-responses induced by furylfuramide (AF-2), as detected by the umu test using Salmonella typhimurium TA1535/pSK1002. In the present report, we studied the time stability of the SOS-inhibition activity in urine. The diurnal and daily changes of SOS-inhibition in the urine were also observed. Results obtained were as follows; 1) SOS-inhibition activity of the urine remained stable more than one month after the urine was frozen. 2) Individual variation was observed in the SOS-inhibition activity of the urine. 3) Total SOS-inhibition activity of per a day showed relatively small variation during experimental days. 4) The SOS-inhibition activity of urine was higher early in the morning than in the daytime. The activity fell gradually with time in the daytime and showed the lowest value in the evening. Then, it rose again at night. Therefore, it is necessary to collect urine at specific times to avoid the differences caused by diurnal changes in SOS-inhibition activity.

Recent advances in traditional plant drugs and orchids.

Abstract: The main objective of this paper is to review recent advances in plant drug research and developments in orchid study, in an attempt to provide useful references for plant drug studies. Plants have been used as medicine for millennia. Out of estimated 250 000 to 350 000 plant species identified so far, about 35 000 are used worldwide for medicinal purposes. It has been confirmed by WHO that herbal medicines serve the health needs of about 80 percent of the world's population; especially for millions of people in the vast rural areas of developing countries. Meanwhile, consumers in developed countries are becoming disillusioned with modern healthcare and are seeking alternatives. The recent resurgence of plant remedies results from several factors: 1) the effectiveness of plant medicines; 2) the side effect of most modern drugs; and 3) the development of science and technology. It has been estimated that in the mid-1990s over 200 companies and research organizations worldwide are screening plant and animal compounds for medicinal properties. Actually, several important drugs used in modern medicine have come from medicinal plant studies, eg, taxol/paclitaxel, vinblastine, vincristine, topotecan, irinotecan, etoposide, teniposide, etc. As for drugs derived from orchids, some novel discoveries, both in phytochemical and pharmacological properties, were reported by some universities. However, studies on plants are very limited. Only about a third of the million or so species of higher plants have been identified and named by scientists. Of those named, only a tiny fraction has been studied. Nowadays the linking of the indigenous knowledge of medicinal plants to modern research activities provides a new approach, which makes the rate of discovery of drugs much more effective than with random collection.

Orchids : A review of uses in traditional medicine, its phytochemistry and pharmacology

Abstract: Many of the epiphytic orchids are used as traditional medicine. Chemical components and pharmacology have been studied in recent 15 years. Medicinal orchids, in general, are not subjected to detailed pharmacological studies. A wide range of chemical compounds are presented including alkaloids, bibenzyl derivatives, flavonoids, phenanthrenes and terpenoids which have been isolated recently from this species. Extracts and metabolites of these plants, particularly those from flowers and leaves, possess useful pharmacological activities. Particular attention has been given to diuretic, anti-rheumatic, anti-inflammatory, anti-carcinogenic, hypoglycemic activities, antimicrobial, anticonvulsive, relaxation, neuroprotective, and antivirus, activities. A comprehensive account of chemical constituents and biological activities is presented and a critical appraisal of the ethnopharmacological issues is included in view of the many recent findings of importance of these orchids. A large number of orchids have been empirically used for treatment of different diseases, thus, several studies have been undertaken to provide scientific proof to justify the medicinal use of various plants in treatment of diseases. The aim of this review is to up-date and to present a comprehensive analysis of traditional and folklore uses, pharmacological reports and phyto-constituents isolated from the orchids family. Key words: Orchids, medicinal plant, traditional uses, chemical constituents, biological activities.

Medicinal orchids and their uses: Tissue culture a potential alternative for conservation

Abstract: Orchids are nature's most extravagant group of flowering plants distributed throughout the world from tropics to high alpine. They exhibit incredible range of diversity in size, shape and color of their flowers. Though orchids are grown primarily as ornamentals, many are used as herbal medicines, food, and other have cultural value by different cultures and tribes in different parts of the world. Orchids have been used in many parts of the world in traditional healing system as well as in the treatment of a number of diseases since the ancient time. Though Orchidaceae is regarded as a largest family of plant kingdom, few studies have been done regarding their medicinal properties. Linking of the indigenous knowledge of medicinal orchids to modern research activities provides a new reliable approach, for the discovery of novel drugs much more effectively than with random collection. Many of these orchids face the extreme danger of extinction due to over-exploitation and habitat loss. Plant tissue culture could be one of the most suitable alternative tools to minimize the pressure on natural population of medicinal orchids and their sustainable utilization. Key words: Medicinal, orchids, propagation, conservation, culture.

Chemistry, bioactivity and quality control of Dendrobium, a commonly used tonic herb in traditional Chinese medicine

Abstract: The fresh or dried stems of many Dendrobium species are well known as one of the most expensive tonics in traditional Chinese medicine Documented as a “superior grade” herbal medicine in the ancient text “Shen Nong’s Herbal Classic”, Dendrobium has been used for thousands of years and is now a popular health food worldwide The main chemical components of Dendrobium are alkaloids, aromatic compounds, sesquiterpenoids and polysaccharides, with multiple biological activities, including immunomodulatory, neuroprotective and anti-tumor effects, etc Various qualitative and quantitative methods have been developed for the quality evaluation of Dendrobium In this review, the research progress since the 1930s relating to the chemistry, bioactivity and quality control of Dendrobium is summarized, existing problems and prospects are also discussed