Objective:Gut-derived serotonin strongly inhibits bone formation by inhibiting osteoblast proliferation.Our previous study demonstrated that the lignan-rich fraction prepared from Sambucus willimasii Hance,a folk herb...Objective:Gut-derived serotonin strongly inhibits bone formation by inhibiting osteoblast proliferation.Our previous study demonstrated that the lignan-rich fraction prepared from Sambucus willimasii Hance,a folk herbal medicine used to treat bone fractures and joint diseases in China,exerted bone-protective effects,and its actions were modulated by suppressing the synthesis of gut-derived serotonin via the inhibition of intestinal tryptophan hydroxylase 1(TPH-1).However,there is no direct evidence for the action of lignans on TPH-1.This study aimed to verify the direct action of lignans on the TPH-1 and its influence on serotonin synthesis and bone properties.Methods:Molecular docking and surface plasmon resonance were performed to determine the affinities of lignans to TPH-1.The cell viability and the protein activity and expression of TPH-1 were measured in RBL2H3 cells.The serum serotonin level and bone mineral density upon lignan treatment in ovariectomized mice were determined.Result:The lignans showed high binding scores and binding affinities to TPH-1,inhibited the activity and protein expression of TPH-1,suppressed the serum serotonin levels in ovariectomized mice as well as promoted bone mineral density.Conclusion:This is the first study to report that lignans are novel TPH-1 inhibitors and that these lignans could be potential agents for the management of serotonin-related diseases,including osteoporosis.展开更多
[Objectives] To explore the antioxidant activity of Sambucus williamsii seed oil. [Methods]DPPH scavenging method and Prussian blue method( total reducing power) were used. S. williamsii seed oil has antioxidant activ...[Objectives] To explore the antioxidant activity of Sambucus williamsii seed oil. [Methods]DPPH scavenging method and Prussian blue method( total reducing power) were used. S. williamsii seed oil has antioxidant activity. In the DPPH scavenging free radical experiment,S. williamsii oil showed the ability to scavenge free radicals,and its scavenging ability had linear relationship with oil concentration( R =0. 999 6). Besides,the IC_(50) value of S. williamsii seed oil scavenging DPPH free radicals was 61. 30 ± 0. 88 mg/mL. In the total reducing power measurement experiment,the S. williamsii seed oil has a reducing ability,and its reducing ability is proportional to the oil concentration,and has the concentration dependence. Through studying the inhibitory effect of S. williamsii seed oil on α-glucosidase,the hypoglycemic activity of S. williamsii seed oil was determined. The ability of samples to inhibit α-glucosidase was judged through measuring the absorbance at 400 nm of the reaction system. [Results]In the concentration range of 1. 56-25. 00 mg/mL,the S. williamsii seed oil can effectively inhibit α-glucosidase,and the inhibition rate was 62. 66%-85. 22%. The animal in vivo experiment was used to determine the hypolipidemic activity of the S. williamsii seed oil. First,a high fat modelwas established,S. williamsii seed oil was given through intragastric administration. Then,total cholesterol( TC),triglyceride( TG),high-density lipoprotein cholesterol( HDL-C),and low density lipoprotein cholesterol( LDL-C) were measured. Through comparison of high,medium and low dose groups of S. williamsii seed oil with the high fat modelcontrol group,it was found that the TC,TG,LDL-C levels were significantly decreased( P < 0. 01) and the HDL-C levels were significantly increased( P < 0. 05),indicating that S. williamsii seed oil can effectively reduce the levels of TC,TG,LDL-C in the serum of hyperlipidemic mice,and effectively inhibit the decrease of HDL-C level,thus S. williamsii seed oil can reduce blood lipids in mice,namely,has hypolipidemic effects. In addition,the greater the dose of S. williamsii seed oil,the more obvious the effect of blood lipid levels in mice,indicating that the hypolipidemic effect of S. williamsii seed oil was dose dependent. [Conclusions] S. williamsii seed oil has reducing ability,and there is a significant dose-effect relationship in the concentration range of 2-10 mg/mL. As natural plant oil,S. williamsii seed oil has the advantages of good stability,small toxic and side effects,and strong effect,and has high value of developing new antioxidants.展开更多
Objective:To investigate the healing effects of two herbal preparations.Methods:For this purpose,106 wistar rats were divided into 9 groups including a control,eucerine,phenytoin,Urtica dioica(U.dioica)(2%),U.dioica(5...Objective:To investigate the healing effects of two herbal preparations.Methods:For this purpose,106 wistar rats were divided into 9 groups including a control,eucerine,phenytoin,Urtica dioica(U.dioica)(2%),U.dioica(5%),Sambucus ebulus(S.ebulus)(2%),S.ebulus(5%),combination(2%),and combination(5%)groups.The control group remained untreated,the eucerin and phenytoin groups were considered as the negative and positive controls respectively,and the remaining groups received different concentrations of the ointments.Full thickness wounds were made.The healing process of the wounds was investigated on day 7,14 and 21 of the experiment.Several factors including the number of fibroblasts,new vessel formation(angiogenesis),thickness of the granulomatous tissues(GT),and the overlying epithelium were analyzed.Results:Among the studied groups,all of the treatment groups were significantly different from the control,eucerin,and phenytoin groups in a positive manner with regard to all studied factors(P 0.05).However,the best results were observed with the S.ebulus(2%) and the combination 2% groups(P 0.05).Conclusions:Topical ointments prepared from the extracts of U.dioica and S.ebulus and their combination possess strong wound healing properties.It is postulated that a synergistic effect may exist between the two extracts since the combination 2% showed better results than the sole extracts.展开更多
Effects of different media,pH values,temperatures,carbon and nitrogen sources on mycelial growth and sporulation of root rot pathogen on Sambucus chinensis was determined in the paper.The results showed that root rot ...Effects of different media,pH values,temperatures,carbon and nitrogen sources on mycelial growth and sporulation of root rot pathogen on Sambucus chinensis was determined in the paper.The results showed that root rot pathogen on S.chinensis was identified as Fusariumsp.The mycelial growth and sporulation of Fusariumsp.in PSA medium was the best;the optimal temperature for mycelial growth and sporulation was from 25℃ to 30℃ and the optimal temperature was 28℃;the suitable pH values for mycelial growth and sporulation was from 5 to 7,and the optimum pH value was 6;the absence or presence of carbon sources had significant effect on growth of Fusariumsp.;sucrose was the best carbon source utilized in mycelial growth,while lactose was the worst; KNO3 was the best nitrogen source utilized in mycelial growth,while(NH4) 2 SO4 was the worst one.展开更多
[Objective] This study was conducted to develop potential natural plant products for controlling walnut blight pathogen and other bacteria. [Method] Inhibitory effects of extracts obtained from 15 plants with 3 solven...[Objective] This study was conducted to develop potential natural plant products for controlling walnut blight pathogen and other bacteria. [Method] Inhibitory effects of extracts obtained from 15 plants with 3 solvents on bacteria were investi- gated by disk diffusion method. [Results] Except the extracts from Magnolia grandi- flora and Typha orientalis, extracts of 13 plant leaves presented inhibitory effects on 5 bacteria strains to certain degrees. Among them, the effect of water extract of Aesculu schinensis on Bacillus sp. XHE8 was the strongest, with inhibition zone di- ameter reaching (31.3+3.9) mm and the ratio to control above 5.0. Four of the 5 tested strains were sensitive to the extracts of Sambucus chinensis, and 3 of them were inhibited by Ophiopegon japonicas extracts and Reineckia camea extracts, with ratios of treatment to control large than 1.5 in all. Leaf extract of A. chinensis had significant anti-bacteria ability, and could be used as a potential plant source for bactericide. [Conclusion] The results laid a foundation for exploring active com- pounds and elucidating the mechanism in it.展开更多
Oxidative stress contributes to the pathogenesis of neurodegenerative diseases.With the aim to find reagents that reduce oxidative stress,a phage display library was screened for peptides mimicking a2,6-sialyllactose(...Oxidative stress contributes to the pathogenesis of neurodegenerative diseases.With the aim to find reagents that reduce oxidative stress,a phage display library was screened for peptides mimicking a2,6-sialyllactose(6'-SL),which is known to beneficially influence neural functions.Using Sambucus nigra lectin,which specifically binds to 6'-SL,we screened a phage display library and found a peptide comprising identical sequences of 12 amino acids.Mimetic peptide,reverse peptide and scrambled peptide were tested for inhibition of 6'-SL binding to the lectin.Indeed,lectin binding to 6'-SL was inhibited by the most frequently identified mimetic peptide,but not by the reverse or scrambled peptides,showing that this peptide mimics 6'-SL.Functionally,mimetic peptide,but not the reverse or scrambled peptides,increased viability and expression of neural cell adhesion molecule L1 in SK-N-SH human neuroblastoma cells,and promoted survival and neurite outgrowth of cultured mouse cerebellar granule neurons challenged by H_20_2-induced oxidative stress.The combined results indicate that the 6'-SL mimetic peptide promotes neuronal survival and neuritogenesis,thus raising hopes for the treatment of neurodegenerative diseases.This study was approved by the Medical Ethics Committee of Shantou University Medical College,China(approval No.SUMC 2014-004)on February 20,2014.展开更多
Chemically based rodent models are used to assess the positive effects promoted by foods and gut microbiota on gut health. Lectins with enzymatic activity, such as type 2 ribosome-inactivating proteins, might also pro...Chemically based rodent models are used to assess the positive effects promoted by foods and gut microbiota on gut health. Lectins with enzymatic activity, such as type 2 ribosome-inactivating proteins, might also prove useful for exploring these issues. Sub-lethal doses of the lectin nigrin from Sambucus nigra L. to mice promoted reversible derangement of gut epithelium by induction of apoptosis of transit amplifying cells of the small intestine crypts in a time-dependent course. The present work seeks to study vitamin B6 accumulation in plasma from an oral bolus in a mouse nigrin model. 24 h after sub-lethal nigrin b treatment, there was clear body weight reduction associated to a notable increase in Evan’s blue stain accumulation in excised small intestine, an increase in myeloperoxidase activity, and a near 50% reduction in plasma accumulation of vitamin B6. Histological analysis of small intestine sections of nigrin b-treated animals also revealed significant derangement of intestinal crypts. Seventy two hours after nigrin b treatment, stain uptake decreased and vitamin B6 accumulation was almost restored despite villi derangement. Large intestine crypts were scarcely or not at all affected. Eight days after nigrin b treatment, vitamin B6 uptake and intestinal crypt structure had fully recovered. The nigrin b mice model supports the view that, under these conditions, the carrier-mediated vitamin B6 uptake component of the small intestine crypts is probably the most active when the vitamin is administered orally as a bolus. The findings provide insights into the suitability of the present mice model for nutritional or drug absorption studies in conditions of partially altered or injured intestinal mucosa.展开更多
Wildfire bears a close relationship with vegetation as its fuel source.The southeastern margin of the Tibetan Plateau witnesses frequent wildfires among various types of vegetation,whereas such wide in-teractions betw...Wildfire bears a close relationship with vegetation as its fuel source.The southeastern margin of the Tibetan Plateau witnesses frequent wildfires among various types of vegetation,whereas such wide in-teractions between wildfire and vegetation remain poorly studied from geological times.In this study,we reported a local fire using sedimentary macroscopic charcoals from the latest Miocene to early Pliocene of the Baoshan Basin in this region,and then inferred the local vegetation at the time of the fire event based chiefly on the coexistent fruit and seed fossil assemblage.Our taxonomic results show that the charcoal assemblage is probably dominated by broadleaved plants and the fruit and seed fossil assemblage is apparently dominated by Salix(Salicaceae)followed by Sambucus(Adoxaceae),suggesting a deciduous broadleaved forest in which the fire likely occurred.Under a seasonally dry climate associated with the Asian monsoon,this type of vegetation might be prone to natural fire,because in the wet rainy season the plants grew well to accumulate biofuel and in the dry season abundant ground litter resulting from leaf decay would be desiccated to become highly flammable.Due to the fire-tolerant habit of Salix as the dominant plant,the forest might be in return adapted to the fire event or even more fires that potentially followed.All these may suggest a close relationship between the fire event and the reconstructed vegetation.Our finding documents a new type of wildfire—vegetation interaction,namely the interaction between wildfire and deciduous broadleaved forest,from the geological past at the southeastern margin of the Tibetan Plateau.It therefore sheds new light on the wildfire history coupling vegetation change in the region.展开更多
Objective: To investigate the antifungal activities of the extracts and sub-fractions of Phlomis olivieri, Verbascum speciosum, Sambucus ebulus and Erigeron hyrcanicus, four Persian medicinal plants used in Iranian f...Objective: To investigate the antifungal activities of the extracts and sub-fractions of Phlomis olivieri, Verbascum speciosum, Sambucus ebulus and Erigeron hyrcanicus, four Persian medicinal plants used in Iranian folk medicine. Methods: Evaluation of the antifungal activity was performed on the clinical isolates of pathogenic fungi including Aspergillus fumigatus, A. flavus, Trichophyton mentagrophytes, T. rubrum, 7. verrucosum, Microsporum canis, M. gypseum and Epidermophyton floccosum, and the yeast Candida albicans. The susceptibility tests were done by agar well diffusion method. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of active extracts and sub-fractions were measured using method of National Committee for Clinical Laboratory Standards (NCCLS). Results: Only P. olivieri sub-fractions were found to have fungicidal activity among the other investigated plants. The MIC and MFC was found to be high in petroleum ether, chloroform and ethyl acetate fractions (100 and 200 mg/mL) against the studied pathogenic fungi and the yeast Candida albicans. P. olivieri sub-fractions significantly inhibited the growth of all pathogenic fungi and the yeast studied. Conclusion: If the antifungal activity of P. olivieri is confirmed by in vivo studies and if the responsible compound (s) is isolated and identified, it could be a good remedy for mycotic infections.展开更多
基金supported by the Natural Science Foundation of Guangdong Province(2021A1515010648)the National Natural Science Foundation of China(81903616)+1 种基金The Hong Kong Polytechnic University Start-up Funding(A0038607)The Mainland-Hong Kong Joint Funding Scheme(ITFMOST:MHX/002/20).
文摘Objective:Gut-derived serotonin strongly inhibits bone formation by inhibiting osteoblast proliferation.Our previous study demonstrated that the lignan-rich fraction prepared from Sambucus willimasii Hance,a folk herbal medicine used to treat bone fractures and joint diseases in China,exerted bone-protective effects,and its actions were modulated by suppressing the synthesis of gut-derived serotonin via the inhibition of intestinal tryptophan hydroxylase 1(TPH-1).However,there is no direct evidence for the action of lignans on TPH-1.This study aimed to verify the direct action of lignans on the TPH-1 and its influence on serotonin synthesis and bone properties.Methods:Molecular docking and surface plasmon resonance were performed to determine the affinities of lignans to TPH-1.The cell viability and the protein activity and expression of TPH-1 were measured in RBL2H3 cells.The serum serotonin level and bone mineral density upon lignan treatment in ovariectomized mice were determined.Result:The lignans showed high binding scores and binding affinities to TPH-1,inhibited the activity and protein expression of TPH-1,suppressed the serum serotonin levels in ovariectomized mice as well as promoted bone mineral density.Conclusion:This is the first study to report that lignans are novel TPH-1 inhibitors and that these lignans could be potential agents for the management of serotonin-related diseases,including osteoporosis.
基金Supported by Fundamental Research Funds for Research Institutes of Heilongjiang Province(2014-02)Key Project of Longjiang Forest Industry(sgzj Y2014021)
文摘[Objectives] To explore the antioxidant activity of Sambucus williamsii seed oil. [Methods]DPPH scavenging method and Prussian blue method( total reducing power) were used. S. williamsii seed oil has antioxidant activity. In the DPPH scavenging free radical experiment,S. williamsii oil showed the ability to scavenge free radicals,and its scavenging ability had linear relationship with oil concentration( R =0. 999 6). Besides,the IC_(50) value of S. williamsii seed oil scavenging DPPH free radicals was 61. 30 ± 0. 88 mg/mL. In the total reducing power measurement experiment,the S. williamsii seed oil has a reducing ability,and its reducing ability is proportional to the oil concentration,and has the concentration dependence. Through studying the inhibitory effect of S. williamsii seed oil on α-glucosidase,the hypoglycemic activity of S. williamsii seed oil was determined. The ability of samples to inhibit α-glucosidase was judged through measuring the absorbance at 400 nm of the reaction system. [Results]In the concentration range of 1. 56-25. 00 mg/mL,the S. williamsii seed oil can effectively inhibit α-glucosidase,and the inhibition rate was 62. 66%-85. 22%. The animal in vivo experiment was used to determine the hypolipidemic activity of the S. williamsii seed oil. First,a high fat modelwas established,S. williamsii seed oil was given through intragastric administration. Then,total cholesterol( TC),triglyceride( TG),high-density lipoprotein cholesterol( HDL-C),and low density lipoprotein cholesterol( LDL-C) were measured. Through comparison of high,medium and low dose groups of S. williamsii seed oil with the high fat modelcontrol group,it was found that the TC,TG,LDL-C levels were significantly decreased( P < 0. 01) and the HDL-C levels were significantly increased( P < 0. 05),indicating that S. williamsii seed oil can effectively reduce the levels of TC,TG,LDL-C in the serum of hyperlipidemic mice,and effectively inhibit the decrease of HDL-C level,thus S. williamsii seed oil can reduce blood lipids in mice,namely,has hypolipidemic effects. In addition,the greater the dose of S. williamsii seed oil,the more obvious the effect of blood lipid levels in mice,indicating that the hypolipidemic effect of S. williamsii seed oil was dose dependent. [Conclusions] S. williamsii seed oil has reducing ability,and there is a significant dose-effect relationship in the concentration range of 2-10 mg/mL. As natural plant oil,S. williamsii seed oil has the advantages of good stability,small toxic and side effects,and strong effect,and has high value of developing new antioxidants.
基金supported by the Faculty of Veterinary Medicine,Urmia University,Urmia,Iran
文摘Objective:To investigate the healing effects of two herbal preparations.Methods:For this purpose,106 wistar rats were divided into 9 groups including a control,eucerine,phenytoin,Urtica dioica(U.dioica)(2%),U.dioica(5%),Sambucus ebulus(S.ebulus)(2%),S.ebulus(5%),combination(2%),and combination(5%)groups.The control group remained untreated,the eucerin and phenytoin groups were considered as the negative and positive controls respectively,and the remaining groups received different concentrations of the ointments.Full thickness wounds were made.The healing process of the wounds was investigated on day 7,14 and 21 of the experiment.Several factors including the number of fibroblasts,new vessel formation(angiogenesis),thickness of the granulomatous tissues(GT),and the overlying epithelium were analyzed.Results:Among the studied groups,all of the treatment groups were significantly different from the control,eucerin,and phenytoin groups in a positive manner with regard to all studied factors(P 0.05).However,the best results were observed with the S.ebulus(2%) and the combination 2% groups(P 0.05).Conclusions:Topical ointments prepared from the extracts of U.dioica and S.ebulus and their combination possess strong wound healing properties.It is postulated that a synergistic effect may exist between the two extracts since the combination 2% showed better results than the sole extracts.
文摘Effects of different media,pH values,temperatures,carbon and nitrogen sources on mycelial growth and sporulation of root rot pathogen on Sambucus chinensis was determined in the paper.The results showed that root rot pathogen on S.chinensis was identified as Fusariumsp.The mycelial growth and sporulation of Fusariumsp.in PSA medium was the best;the optimal temperature for mycelial growth and sporulation was from 25℃ to 30℃ and the optimal temperature was 28℃;the suitable pH values for mycelial growth and sporulation was from 5 to 7,and the optimum pH value was 6;the absence or presence of carbon sources had significant effect on growth of Fusariumsp.;sucrose was the best carbon source utilized in mycelial growth,while lactose was the worst; KNO3 was the best nitrogen source utilized in mycelial growth,while(NH4) 2 SO4 was the worst one.
基金Supported by National Natural Science Foundation(31200488,31370692)Surface Project of Natural Science Foundation of Hubei Province(2014CFB573)~~
文摘[Objective] This study was conducted to develop potential natural plant products for controlling walnut blight pathogen and other bacteria. [Method] Inhibitory effects of extracts obtained from 15 plants with 3 solvents on bacteria were investi- gated by disk diffusion method. [Results] Except the extracts from Magnolia grandi- flora and Typha orientalis, extracts of 13 plant leaves presented inhibitory effects on 5 bacteria strains to certain degrees. Among them, the effect of water extract of Aesculu schinensis on Bacillus sp. XHE8 was the strongest, with inhibition zone di- ameter reaching (31.3+3.9) mm and the ratio to control above 5.0. Four of the 5 tested strains were sensitive to the extracts of Sambucus chinensis, and 3 of them were inhibited by Ophiopegon japonicas extracts and Reineckia camea extracts, with ratios of treatment to control large than 1.5 in all. Leaf extract of A. chinensis had significant anti-bacteria ability, and could be used as a potential plant source for bactericide. [Conclusion] The results laid a foundation for exploring active com- pounds and elucidating the mechanism in it.
基金supported by the National Natural Science Foundation of China,No.81471279 and No.81171138(to WJZ)Talent Support Grant from Shantou University Medical College,China,No.2501220118(to WJZ)the Li Kashing Foundation,No.LD030302(to MS)
文摘Oxidative stress contributes to the pathogenesis of neurodegenerative diseases.With the aim to find reagents that reduce oxidative stress,a phage display library was screened for peptides mimicking a2,6-sialyllactose(6'-SL),which is known to beneficially influence neural functions.Using Sambucus nigra lectin,which specifically binds to 6'-SL,we screened a phage display library and found a peptide comprising identical sequences of 12 amino acids.Mimetic peptide,reverse peptide and scrambled peptide were tested for inhibition of 6'-SL binding to the lectin.Indeed,lectin binding to 6'-SL was inhibited by the most frequently identified mimetic peptide,but not by the reverse or scrambled peptides,showing that this peptide mimics 6'-SL.Functionally,mimetic peptide,but not the reverse or scrambled peptides,increased viability and expression of neural cell adhesion molecule L1 in SK-N-SH human neuroblastoma cells,and promoted survival and neurite outgrowth of cultured mouse cerebellar granule neurons challenged by H_20_2-induced oxidative stress.The combined results indicate that the 6'-SL mimetic peptide promotes neuronal survival and neuritogenesis,thus raising hopes for the treatment of neurodegenerative diseases.This study was approved by the Medical Ethics Committee of Shantou University Medical College,China(approval No.SUMC 2014-004)on February 20,2014.
文摘Chemically based rodent models are used to assess the positive effects promoted by foods and gut microbiota on gut health. Lectins with enzymatic activity, such as type 2 ribosome-inactivating proteins, might also prove useful for exploring these issues. Sub-lethal doses of the lectin nigrin from Sambucus nigra L. to mice promoted reversible derangement of gut epithelium by induction of apoptosis of transit amplifying cells of the small intestine crypts in a time-dependent course. The present work seeks to study vitamin B6 accumulation in plasma from an oral bolus in a mouse nigrin model. 24 h after sub-lethal nigrin b treatment, there was clear body weight reduction associated to a notable increase in Evan’s blue stain accumulation in excised small intestine, an increase in myeloperoxidase activity, and a near 50% reduction in plasma accumulation of vitamin B6. Histological analysis of small intestine sections of nigrin b-treated animals also revealed significant derangement of intestinal crypts. Seventy two hours after nigrin b treatment, stain uptake decreased and vitamin B6 accumulation was almost restored despite villi derangement. Large intestine crypts were scarcely or not at all affected. Eight days after nigrin b treatment, vitamin B6 uptake and intestinal crypt structure had fully recovered. The nigrin b mice model supports the view that, under these conditions, the carrier-mediated vitamin B6 uptake component of the small intestine crypts is probably the most active when the vitamin is administered orally as a bolus. The findings provide insights into the suitability of the present mice model for nutritional or drug absorption studies in conditions of partially altered or injured intestinal mucosa.
基金supported by the National Natural Science Foundation of China(No.41972023)the Natural Science Foundation of Yunnan Province(No.202301AT070374)+1 种基金the Ten-thousand Talents Program of Yunnan Province(No.YNWR-QNBJ-2019-261)the West Light Foundation of the Chinese Academy of Sciences to Y.-J.Huang.
文摘Wildfire bears a close relationship with vegetation as its fuel source.The southeastern margin of the Tibetan Plateau witnesses frequent wildfires among various types of vegetation,whereas such wide in-teractions between wildfire and vegetation remain poorly studied from geological times.In this study,we reported a local fire using sedimentary macroscopic charcoals from the latest Miocene to early Pliocene of the Baoshan Basin in this region,and then inferred the local vegetation at the time of the fire event based chiefly on the coexistent fruit and seed fossil assemblage.Our taxonomic results show that the charcoal assemblage is probably dominated by broadleaved plants and the fruit and seed fossil assemblage is apparently dominated by Salix(Salicaceae)followed by Sambucus(Adoxaceae),suggesting a deciduous broadleaved forest in which the fire likely occurred.Under a seasonally dry climate associated with the Asian monsoon,this type of vegetation might be prone to natural fire,because in the wet rainy season the plants grew well to accumulate biofuel and in the dry season abundant ground litter resulting from leaf decay would be desiccated to become highly flammable.Due to the fire-tolerant habit of Salix as the dominant plant,the forest might be in return adapted to the fire event or even more fires that potentially followed.All these may suggest a close relationship between the fire event and the reconstructed vegetation.Our finding documents a new type of wildfire—vegetation interaction,namely the interaction between wildfire and deciduous broadleaved forest,from the geological past at the southeastern margin of the Tibetan Plateau.It therefore sheds new light on the wildfire history coupling vegetation change in the region.
基金Supports from the Pharmaceutical Sciences Branch,Islamic Azad University(IAU)
文摘Objective: To investigate the antifungal activities of the extracts and sub-fractions of Phlomis olivieri, Verbascum speciosum, Sambucus ebulus and Erigeron hyrcanicus, four Persian medicinal plants used in Iranian folk medicine. Methods: Evaluation of the antifungal activity was performed on the clinical isolates of pathogenic fungi including Aspergillus fumigatus, A. flavus, Trichophyton mentagrophytes, T. rubrum, 7. verrucosum, Microsporum canis, M. gypseum and Epidermophyton floccosum, and the yeast Candida albicans. The susceptibility tests were done by agar well diffusion method. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of active extracts and sub-fractions were measured using method of National Committee for Clinical Laboratory Standards (NCCLS). Results: Only P. olivieri sub-fractions were found to have fungicidal activity among the other investigated plants. The MIC and MFC was found to be high in petroleum ether, chloroform and ethyl acetate fractions (100 and 200 mg/mL) against the studied pathogenic fungi and the yeast Candida albicans. P. olivieri sub-fractions significantly inhibited the growth of all pathogenic fungi and the yeast studied. Conclusion: If the antifungal activity of P. olivieri is confirmed by in vivo studies and if the responsible compound (s) is isolated and identified, it could be a good remedy for mycotic infections.