Evolutionary transitions from sexual to asexual reproduction should have significant influences on genetic divergence and polymorphism at the genome level.Plant lineages with diverse reproductive systems provide oppor...Evolutionary transitions from sexual to asexual reproduction should have significant influences on genetic divergence and polymorphism at the genome level.Plant lineages with diverse reproductive systems provide opportunities to investigate this question using comparative approaches and studies of molecular evolution.We investigated evidence for differences among the transcriptomes of 19 Dioscorea species(wild yams)with diverse reproductive systems.These included sexual species,those that propagate primarily by bulbils,and those with mixed sexual and asexual reproductive modes.We examined how transitions between these reproductive systems affected between-species divergence and within-species polymorphism.Primarily asexual species exhibited a reduced efficacy of natural selection and accumulation of deleterious mutations for both divergence and polymorphism.In contrast,species with mixed reproductive strategies involving both seed and clonal reproduction showed no evidence of an increased fixation of harmful mutations at the divergence level,while an accumulation of genetic load present in polymorphism was evident.Our study indicates that the genetic consequences of evolutionary transitions from sexual to predominantly clonal reproduction is likely to depend on both the duration and extent of asexuality occurring in populations.展开更多
Objective:To investigate the therapeutic effects and safety of Dioscorea Decoction combined with Coix Seed in treating cancer cachexia(spleen-kidney Yang deficiency syndrome)in malignant tumor patients.Methods:A total...Objective:To investigate the therapeutic effects and safety of Dioscorea Decoction combined with Coix Seed in treating cancer cachexia(spleen-kidney Yang deficiency syndrome)in malignant tumor patients.Methods:A total of 90 patients with cancer cachexia admitted between June 2024 and June 2025 were randomly divided into a control group and a study group(45 cases each)using a random number generator.Both groups received antitumor therapy,oral megestrol acetate capsules,and conventional nutritional intervention.The study group additionally received oral Dioscorea Decoction combined with Coix Seed.Differences in TCM syndrome scores,nutritional indicators(serum albumin,hemoglobin),and adverse reactions were compared before and after treatment.Results:Baseline TCM syndrome scores and nutritional indicators were comparable between the two groups before treatment.After treatment,both groups showed significant reductions in TCM syndrome scores and increases in serum albumin and hemoglobin levels.The study group exhibited lower TCM syndrome scores and higher serum albumin and hemoglobin levels than the control group,with statistically significant differences.No significant difference in adverse reaction rates was observed between the two groups.Conclusion:Dioscorea Decoction combined with Coix Seed can further improve nutritional status,alleviate clinical symptoms,and demonstrate good safety in treating cancer cachexia patients.展开更多
[Objective] This study was to explore the effect of purple yam on the nutritional and physiological functions of rats.[Method] Forty SD rats were randomly divided into four groups with ten rats in each group which wer...[Objective] This study was to explore the effect of purple yam on the nutritional and physiological functions of rats.[Method] Forty SD rats were randomly divided into four groups with ten rats in each group which were reared with artificial semisynthetic feed added with 10% steamed yam powder.The four groups,the casein（CK） group which was used as the control,the purple yam（PY） group,the Tiegun yam（TY） group and common Huai yam（HY） group,were supplied with feed of equal content of energy,protein and fat.The rats were pair-fed for 56 days to observe changes of relevant nutritional and physiological indices.[Result] There were no significant differences of body weight,food conversion rate and organ indices between rats in PY group and CK group.Mean corpuscular hemoglobin in PY group was significantly lower than that in CK group;hemoglobin showed no significant difference with that in CK group;eosnophils was lower than that in CK group.Low density lipoprotein-cholesterol,total cholesterol and atherogenic index in PY group were lower than that in the other three groups;anti-atherogenic index was the highest among the four groups,while showing no significant difference;triglyceride content was lower than that in CK group.Among the antioxidant indices,the activity of catalase and superoxide dismutase were higher than that in CK group,while malondialdehyde content was lower than that in CK group.[Conclusion] Purple yam showed the trend of reducing the content of blood glucose,total cholesterol,low density lipoprotein-cholesterol,triglyceride,malondialdehyde,and raising the activity of glutathione peroxidase,superoxide dismutase and catalase,thus having certain antioxidative function.展开更多
AIM: To investigate the chemical constituents of Dioscorea zingiberensis C. H. Wright. METHODS: The compounds were isolated by various chromatographic techniques, and the structures of the new steroidal saponins were ...AIM: To investigate the chemical constituents of Dioscorea zingiberensis C. H. Wright. METHODS: The compounds were isolated by various chromatographic techniques, and the structures of the new steroidal saponins were elucidated by extensive 1D- and 2D-NMR, MS, and IR spectral analysis. RESULTS: The 70% EtOH extract of the rhizomes of Dioscorea zingiberensis afforded two new steroidal saponins, zingiberenosides A(1) and B(2), along with eight known analogues, 3β, 26-dihydroxy-25(R)-furosta-△5, 20(22)-diene-3-O-α-Lrhamnopyranosyl-(1→2)-O-β-D-glucopyranoside(3), methyl parvifloside(4), deltoside(5), methyl deltoside(6), zingiberensis new saponin(7), deltonin(8), progenin III(9) and diosgenin-diglucoside(10). CONCLUSION: Two new steroidal saponins were isolated from Dioscorea zingiberensis and their structures determined.展开更多
The aim of this study is to evaluate the efficacy of total saponins of Dioscorea（TSD）, an extract of the Chinese herbal Bi Xie, on hyperuricemia and to elucidate the underlying mechanisms. The rat hyperuricemia mode...The aim of this study is to evaluate the efficacy of total saponins of Dioscorea（TSD）, an extract of the Chinese herbal Bi Xie, on hyperuricemia and to elucidate the underlying mechanisms. The rat hyperuricemia model was established by administration of adenine. Thirty-two rats were randomly allocated into 4 groups： model group, low/high-dose TSD-treated groups, and allopurinol-treated group. Meanwhile, 8 rats were used as normal controls. Serum uric acid（UA）, blood urea nitrogen（BUN）, serum creatinine（Scr）, and organic anion transporting polypeptide 1A1（OATP1A1） levels were measured. Comparison between the model group and treatment（allopurinol and TSD） groups showed the serum UA levels were significantly decreased in treatment groups. TSD had similar effects to allopurinol. It was found that the OATP1A1 protein expression levels in treatment groups were higher than in model group and normal controls. And different from the allopurinol-treated groups, TSD-treated group had elevated OATP1A1 expression levels in the stomach, liver, small intestine and large intestine tissues. It was suggested that TSD may facilitate the excretion of UA and lower UA levels by up-regulating OATP1A1 expression.展开更多
Two novel 27-norergostanol steroids, panthogenins A （1） and B （2）, possessing unusual rings E and F featuring a ketal moiety at C-25 were isolated from rhizomes ofDioscorea panthaica. Their structures and relative...Two novel 27-norergostanol steroids, panthogenins A （1） and B （2）, possessing unusual rings E and F featuring a ketal moiety at C-25 were isolated from rhizomes ofDioscorea panthaica. Their structures and relative configurations were elucidated by extensive spectroscopic methods including 1D and 2D NMR techniques, and the structure of panthogenin A was further confirmed by X-ray crystallography. Both compounds showed potent in vitro insulin sensitizing activity.展开更多
O-a-D-Glucopyranosyl-furost-5(6),20(22)-dien-3a,26-diol 1, a new furostanol saponin, was isolated from the water-extract of Dioscorea nipponica Mak., the raw material of a traditional Chinese herbal medicine Wei Ao Xi...O-a-D-Glucopyranosyl-furost-5(6),20(22)-dien-3a,26-diol 1, a new furostanol saponin, was isolated from the water-extract of Dioscorea nipponica Mak., the raw material of a traditional Chinese herbal medicine Wei Ao Xin. The structure of 1 was determined on the basis of its spectral data especially by NMR spectroscopy. The result provides the first example of naturally occurring furostanol saponins with a single saccharide chain at the C-26 position.展开更多
In the present study, in vitro ovule culture technique was used to obtain interspecific cross combination of Dioscorea rotundata ufenyi and Dioscorea bulbifera wild. Ten days after pollination, ovules were excised and...In the present study, in vitro ovule culture technique was used to obtain interspecific cross combination of Dioscorea rotundata ufenyi and Dioscorea bulbifera wild. Ten days after pollination, ovules were excised and cultured onto 1/2 strength Murashige and Skoog (MS) medium (Basal salt mixture + Vitamins) supplemented with 6% sucrose, 0.7% agar and plant growth hormones such as GA3, BAP, Picrolam and TDZ. Cultured ovules were transferred on 1/2 MS medium with 3% sucrose and 0.7% agar after three weeks. 40 days after pollination, germination was observed from 7 months cultured ovule between D. rotundata ufenyi x D. bulbifera wild. Hybridity of the regenerated plant was checked by flow cytometric method. A close relation was observed between the fluorescence intensity of the obtained progeny with one of the parents’ fluorescence. The observed progeny can be closely correlated with an apomictic tissue from an ovule parent of D. rotundata ufenyi. Plantlets derived from ovule culture were proliferated through in vitro shoot multiplication with hormonal concentration (0.5 mg/l BAP) supplemented with 1/2 strength MS medium. Obtained ovule culture derived in vitro plantlets were successfully hardened, acclimatized and transferred to the field, where they survived and grew normally. In plant breeding, interspecific crossing is very important technique, enabling the time needed to produce homozygous lines to be shortened as compared to the conventional plant breeding techniques.展开更多
Yam （Dioscorea spp.）, has been aptly described as an orphan crop. It has suffered institutional neglect from time immemorial. Until this study there were no formally released yam varieties in Ghana. The farmer parti...Yam （Dioscorea spp.）, has been aptly described as an orphan crop. It has suffered institutional neglect from time immemorial. Until this study there were no formally released yam varieties in Ghana. The farmer participatory breeding approach was adapted to fast-track the development and release of three new yam varieties in Ghana. This paper uses the breeding process as a case study and conducts a SWOT analysis to provide guidelines for breeding for crops in Low External Input Agriculture. It was faster than conventional breeding in varietal development. Scientific quality of Farmer Participatory Breeding is as good as conventional breeding. Farmer Participatory Breeding is a must for breeding yam in Ghana. Ultimately, three genotypes 2000/001, KUP2000/001 and TDr89/02665 were accepted and released as new varieties ＂CRIKukrupa＂, ＂CRIPona＂ and ＂Mankrong Pona＂ respectively in March 2005. Danger of omission of some promising genotypes in the course of varietal development and danger of opinion group cabalizing the group discussions were identified as potential threats to the approach. Effective research-extension-farmer linkage was identified as extremely vital to the success of the approach. Farmer participatory breeding process was also sustainable and more efficient than conventional breeding in varietal selection in yam breeding.展开更多
The author made innovation on cultivation technology of Dioscorea oppo- site based on orientation tuberization. According to large furrow, big tuber, and lots of soils, a tuber bed is established suitable for yam grow...The author made innovation on cultivation technology of Dioscorea oppo- site based on orientation tuberization. According to large furrow, big tuber, and lots of soils, a tuber bed is established suitable for yam growth, and a vertically band- based orientation is introduced. Specifically, soils are ground and colored bands are paved in bottom of furrows where tubers can be cultivated. At harvest, band soils can be removed to collect tubers. It is simple and easy. The yield can be as high as 75 000 kg/hm2. It is applicable in a variety of lands, especially for arid areas, mountains areas or under-forest lands with slopes from 10°to 25°. Semi-mechanical or mechanical planting and harvest can be applied with promising prospects.展开更多
Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-com...Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-compressed water extraction(HCW)and enzyme-assisted extraction(EAE),on the yields,physicochemical properties,hypoglycemic and antioxidant activities of polysaccharides from DTTP were studied and compared.Among these DTTP polysaccharides,DTTP-HA was outstanding in several respects.DTTP-HA was the most water soluble;it had the highest total carbohydrate content(85.08%),the highest uronic acid(13.20%)and the highest thermal stability.DTTP-HA and DTTP-W possessed a triple-helix structure.These 4 kinds of polysaccharides have the same types of monosaccharides,but in different molar percentages.Extraction method had a significant impact on the microstructures of the extracted polysaccharides.DTT-HA exhibited irregular structure with many holes.Among the 4 extracted methods,the DTTP-HA and DTTP-W initially exhibited higher hypoglycemic and antioxidant activities.The better bioactivities of DTTP-HA may be related to the above factors.The findings indicated that acid extraction is an effective method to extract polysaccharides with high biological activities from DTTP.展开更多
Bioactivity-guided fractionation led to the isolation of a new steroidal saponin, orbiculatoside B, together with a pair of furostanol saponins, protobioside and methyl protobioside, from the fresh rhizomes of Dioscor...Bioactivity-guided fractionation led to the isolation of a new steroidal saponin, orbiculatoside B, together with a pair of furostanol saponins, protobioside and methyl protobioside, from the fresh rhizomes of Dioscorea deltoidea Wall var. orbiculata. The new compound was identified to be isonarthogenin 3 O - a - L - rhamnopyranosyl (12) - [ a - L - rhamnopyranosyl - ( 1 4 ) ] - b - D - glucopyranoside by various NMR techniques in combination with chemical methods. The three saponins showed strong activity against Pyricularia oryzae, and were cytotoxic to cancer cell line K562, HCT-15, A549, and A2780a in vitro.展开更多
基金supported by the Top-notch Young Talents Project of Yunnan Province(YNWR-QNBJ-2019-203)the National Natural Science Foundation of China(32470394)the Key Basic Research Programof Yunnan Province(202201AS070057,202101BC070003,and 202103AC100003).
文摘Evolutionary transitions from sexual to asexual reproduction should have significant influences on genetic divergence and polymorphism at the genome level.Plant lineages with diverse reproductive systems provide opportunities to investigate this question using comparative approaches and studies of molecular evolution.We investigated evidence for differences among the transcriptomes of 19 Dioscorea species(wild yams)with diverse reproductive systems.These included sexual species,those that propagate primarily by bulbils,and those with mixed sexual and asexual reproductive modes.We examined how transitions between these reproductive systems affected between-species divergence and within-species polymorphism.Primarily asexual species exhibited a reduced efficacy of natural selection and accumulation of deleterious mutations for both divergence and polymorphism.In contrast,species with mixed reproductive strategies involving both seed and clonal reproduction showed no evidence of an increased fixation of harmful mutations at the divergence level,while an accumulation of genetic load present in polymorphism was evident.Our study indicates that the genetic consequences of evolutionary transitions from sexual to predominantly clonal reproduction is likely to depend on both the duration and extent of asexuality occurring in populations.
文摘Objective:To investigate the therapeutic effects and safety of Dioscorea Decoction combined with Coix Seed in treating cancer cachexia(spleen-kidney Yang deficiency syndrome)in malignant tumor patients.Methods:A total of 90 patients with cancer cachexia admitted between June 2024 and June 2025 were randomly divided into a control group and a study group(45 cases each)using a random number generator.Both groups received antitumor therapy,oral megestrol acetate capsules,and conventional nutritional intervention.The study group additionally received oral Dioscorea Decoction combined with Coix Seed.Differences in TCM syndrome scores,nutritional indicators(serum albumin,hemoglobin),and adverse reactions were compared before and after treatment.Results:Baseline TCM syndrome scores and nutritional indicators were comparable between the two groups before treatment.After treatment,both groups showed significant reductions in TCM syndrome scores and increases in serum albumin and hemoglobin levels.The study group exhibited lower TCM syndrome scores and higher serum albumin and hemoglobin levels than the control group,with statistically significant differences.No significant difference in adverse reaction rates was observed between the two groups.Conclusion:Dioscorea Decoction combined with Coix Seed can further improve nutritional status,alleviate clinical symptoms,and demonstrate good safety in treating cancer cachexia patients.
基金Supported by the Special Fund for Construction of Scientific and Technological Innovation Ability of BAAFS(KJCX201101010-22)~~
文摘[Objective] This study was to explore the effect of purple yam on the nutritional and physiological functions of rats.[Method] Forty SD rats were randomly divided into four groups with ten rats in each group which were reared with artificial semisynthetic feed added with 10% steamed yam powder.The four groups,the casein（CK） group which was used as the control,the purple yam（PY） group,the Tiegun yam（TY） group and common Huai yam（HY） group,were supplied with feed of equal content of energy,protein and fat.The rats were pair-fed for 56 days to observe changes of relevant nutritional and physiological indices.[Result] There were no significant differences of body weight,food conversion rate and organ indices between rats in PY group and CK group.Mean corpuscular hemoglobin in PY group was significantly lower than that in CK group;hemoglobin showed no significant difference with that in CK group;eosnophils was lower than that in CK group.Low density lipoprotein-cholesterol,total cholesterol and atherogenic index in PY group were lower than that in the other three groups;anti-atherogenic index was the highest among the four groups,while showing no significant difference;triglyceride content was lower than that in CK group.Among the antioxidant indices,the activity of catalase and superoxide dismutase were higher than that in CK group,while malondialdehyde content was lower than that in CK group.[Conclusion] Purple yam showed the trend of reducing the content of blood glucose,total cholesterol,low density lipoprotein-cholesterol,triglyceride,malondialdehyde,and raising the activity of glutathione peroxidase,superoxide dismutase and catalase,thus having certain antioxidative function.
基金Natural Science Foundation of Guangxi Academy of Agricultural Sciences(No.2003014 and 2009014)The Project ofSpecial Funds for the Employment of Outstanding Experts in Guangxi
基金supported by the Science and Technology Achievement Transformation Project of Jiangsu Province(No.BA2010144)the scientific and technological major special project for "Significant Creation of New Drugs"(No.2012ZX09101231)
文摘AIM: To investigate the chemical constituents of Dioscorea zingiberensis C. H. Wright. METHODS: The compounds were isolated by various chromatographic techniques, and the structures of the new steroidal saponins were elucidated by extensive 1D- and 2D-NMR, MS, and IR spectral analysis. RESULTS: The 70% EtOH extract of the rhizomes of Dioscorea zingiberensis afforded two new steroidal saponins, zingiberenosides A(1) and B(2), along with eight known analogues, 3β, 26-dihydroxy-25(R)-furosta-△5, 20(22)-diene-3-O-α-Lrhamnopyranosyl-(1→2)-O-β-D-glucopyranoside(3), methyl parvifloside(4), deltoside(5), methyl deltoside(6), zingiberensis new saponin(7), deltonin(8), progenin III(9) and diosgenin-diglucoside(10). CONCLUSION: Two new steroidal saponins were isolated from Dioscorea zingiberensis and their structures determined.
基金supported by grants from the National Natural Science Foundation of China(No.81072806,and No.81373500)Natural Science Foundation of Guangdong Province(No.S2012010009277)Traditional Chinese Medicine Bureau of Guangdong Province(No.20141046)
文摘The aim of this study is to evaluate the efficacy of total saponins of Dioscorea（TSD）, an extract of the Chinese herbal Bi Xie, on hyperuricemia and to elucidate the underlying mechanisms. The rat hyperuricemia model was established by administration of adenine. Thirty-two rats were randomly allocated into 4 groups： model group, low/high-dose TSD-treated groups, and allopurinol-treated group. Meanwhile, 8 rats were used as normal controls. Serum uric acid（UA）, blood urea nitrogen（BUN）, serum creatinine（Scr）, and organic anion transporting polypeptide 1A1（OATP1A1） levels were measured. Comparison between the model group and treatment（allopurinol and TSD） groups showed the serum UA levels were significantly decreased in treatment groups. TSD had similar effects to allopurinol. It was found that the OATP1A1 protein expression levels in treatment groups were higher than in model group and normal controls. And different from the allopurinol-treated groups, TSD-treated group had elevated OATP1A1 expression levels in the stomach, liver, small intestine and large intestine tissues. It was suggested that TSD may facilitate the excretion of UA and lower UA levels by up-regulating OATP1A1 expression.
基金Financial support from the National Natural Science Foundation of China (Nos.21072184,30973634 and 81173536)
文摘Two novel 27-norergostanol steroids, panthogenins A （1） and B （2）, possessing unusual rings E and F featuring a ketal moiety at C-25 were isolated from rhizomes ofDioscorea panthaica. Their structures and relative configurations were elucidated by extensive spectroscopic methods including 1D and 2D NMR techniques, and the structure of panthogenin A was further confirmed by X-ray crystallography. Both compounds showed potent in vitro insulin sensitizing activity.
文摘O-a-D-Glucopyranosyl-furost-5(6),20(22)-dien-3a,26-diol 1, a new furostanol saponin, was isolated from the water-extract of Dioscorea nipponica Mak., the raw material of a traditional Chinese herbal medicine Wei Ao Xin. The structure of 1 was determined on the basis of its spectral data especially by NMR spectroscopy. The result provides the first example of naturally occurring furostanol saponins with a single saccharide chain at the C-26 position.
文摘In the present study, in vitro ovule culture technique was used to obtain interspecific cross combination of Dioscorea rotundata ufenyi and Dioscorea bulbifera wild. Ten days after pollination, ovules were excised and cultured onto 1/2 strength Murashige and Skoog (MS) medium (Basal salt mixture + Vitamins) supplemented with 6% sucrose, 0.7% agar and plant growth hormones such as GA3, BAP, Picrolam and TDZ. Cultured ovules were transferred on 1/2 MS medium with 3% sucrose and 0.7% agar after three weeks. 40 days after pollination, germination was observed from 7 months cultured ovule between D. rotundata ufenyi x D. bulbifera wild. Hybridity of the regenerated plant was checked by flow cytometric method. A close relation was observed between the fluorescence intensity of the obtained progeny with one of the parents’ fluorescence. The observed progeny can be closely correlated with an apomictic tissue from an ovule parent of D. rotundata ufenyi. Plantlets derived from ovule culture were proliferated through in vitro shoot multiplication with hormonal concentration (0.5 mg/l BAP) supplemented with 1/2 strength MS medium. Obtained ovule culture derived in vitro plantlets were successfully hardened, acclimatized and transferred to the field, where they survived and grew normally. In plant breeding, interspecific crossing is very important technique, enabling the time needed to produce homozygous lines to be shortened as compared to the conventional plant breeding techniques.
文摘Yam （Dioscorea spp.）, has been aptly described as an orphan crop. It has suffered institutional neglect from time immemorial. Until this study there were no formally released yam varieties in Ghana. The farmer participatory breeding approach was adapted to fast-track the development and release of three new yam varieties in Ghana. This paper uses the breeding process as a case study and conducts a SWOT analysis to provide guidelines for breeding for crops in Low External Input Agriculture. It was faster than conventional breeding in varietal development. Scientific quality of Farmer Participatory Breeding is as good as conventional breeding. Farmer Participatory Breeding is a must for breeding yam in Ghana. Ultimately, three genotypes 2000/001, KUP2000/001 and TDr89/02665 were accepted and released as new varieties ＂CRIKukrupa＂, ＂CRIPona＂ and ＂Mankrong Pona＂ respectively in March 2005. Danger of omission of some promising genotypes in the course of varietal development and danger of opinion group cabalizing the group discussions were identified as potential threats to the approach. Effective research-extension-farmer linkage was identified as extremely vital to the success of the approach. Farmer participatory breeding process was also sustainable and more efficient than conventional breeding in varietal selection in yam breeding.
基金Supported by Guangxi Academy of Agricultural Sciences Team Program(2016YT60)~~
文摘The author made innovation on cultivation technology of Dioscorea oppo- site based on orientation tuberization. According to large furrow, big tuber, and lots of soils, a tuber bed is established suitable for yam growth, and a vertically band- based orientation is introduced. Specifically, soils are ground and colored bands are paved in bottom of furrows where tubers can be cultivated. At harvest, band soils can be removed to collect tubers. It is simple and easy. The yield can be as high as 75 000 kg/hm2. It is applicable in a variety of lands, especially for arid areas, mountains areas or under-forest lands with slopes from 10°to 25°. Semi-mechanical or mechanical planting and harvest can be applied with promising prospects.
基金the financial support provided by Zhengzhou 1125 Talents Gathering Project (2018)the Doctor startup fund of Henan Agricultural University (30500431)
文摘Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-compressed water extraction(HCW)and enzyme-assisted extraction(EAE),on the yields,physicochemical properties,hypoglycemic and antioxidant activities of polysaccharides from DTTP were studied and compared.Among these DTTP polysaccharides,DTTP-HA was outstanding in several respects.DTTP-HA was the most water soluble;it had the highest total carbohydrate content(85.08%),the highest uronic acid(13.20%)and the highest thermal stability.DTTP-HA and DTTP-W possessed a triple-helix structure.These 4 kinds of polysaccharides have the same types of monosaccharides,but in different molar percentages.Extraction method had a significant impact on the microstructures of the extracted polysaccharides.DTT-HA exhibited irregular structure with many holes.Among the 4 extracted methods,the DTTP-HA and DTTP-W initially exhibited higher hypoglycemic and antioxidant activities.The better bioactivities of DTTP-HA may be related to the above factors.The findings indicated that acid extraction is an effective method to extract polysaccharides with high biological activities from DTTP.
文摘Bioactivity-guided fractionation led to the isolation of a new steroidal saponin, orbiculatoside B, together with a pair of furostanol saponins, protobioside and methyl protobioside, from the fresh rhizomes of Dioscorea deltoidea Wall var. orbiculata. The new compound was identified to be isonarthogenin 3 O - a - L - rhamnopyranosyl (12) - [ a - L - rhamnopyranosyl - ( 1 4 ) ] - b - D - glucopyranoside by various NMR techniques in combination with chemical methods. The three saponins showed strong activity against Pyricularia oryzae, and were cytotoxic to cancer cell line K562, HCT-15, A549, and A2780a in vitro.
