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Anti-melanogenic properties of FBCC-EP850 derived from Carex pumila Thunb
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作者 Mirissa Hewage Dumindu Kavinda Jinkuk Park +2 位作者 Nayeong Kim Yung Hyun Choi Gi-Young Kim 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第11期477-485,共9页
Objective:To elucidate the anti-melanogenic potential of Carex pumila Thunb.extract(FBCC-EP850).Methods:A collection of 180 plant extracts was tested for inhibition of mushroom tyrosinase activity using an in vitro as... Objective:To elucidate the anti-melanogenic potential of Carex pumila Thunb.extract(FBCC-EP850).Methods:A collection of 180 plant extracts was tested for inhibition of mushroom tyrosinase activity using an in vitro assay.Among them,FBCC-EP850 exhibited the most promising inhibitory activity.Further analysis was conducted to investigate its mechanisms and therapeutic potential in reducing melanogenesis in B16F10 melanoma cells and zebrafish larvae.Results:FBCC-EP850 inhibited mushroom tyrosinase activity in a dose-dependent manner,with a half-maximal inhibitory concentration of 45.83μg/mL.FBCC-EP850 at concentrations up to 50μg/mL demonstrated minimal cytotoxicity against B16F10 melanoma cells and no adverse effects on zebrafish larvae.Treatment with 50μg/mL of FBCC-EP850 significantly reducedα-melanocyte stimulating hormone-induced melanin production and suppressed cellular tyrosinase activity in B16F10 melanoma cells.Additionally,FBCC-EP850 at 25 and 50μg/mL effectively diminished hyperpigmentation inα-melanocyte stimulating hormone-stimulated zebrafish larvae.Its anti-melanogenic action could be attributed to modulation of the cAMP-CREB-MITF signaling pathway.Conclusions:Carex pumila extract can inhibit melanogenesis by modulating the cAMP-CREB-MITF signaling pathway,which can be used as a promising candidate for treating hyperpigmentation disorders. 展开更多
关键词 Carex pumila Thunb. MELANOGENESIS TYROSINASE cAMP-CREB-MITF signaling
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新疆短命植物小拟南芥(Arabidopsis pumila)种子萌发特性及其生态适应性 被引量:20
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作者 张海波 刘彭 +2 位作者 刘立鸿 兰海燕 张富春 《生态学报》 CAS CSCD 北大核心 2007年第10期4310-4316,共7页
通过显微结构及不同处理条件下种子萌发率的观察,对早春短命植物小拟南芥(Arabidopsis pumila)种子萌发特性及影响因素进行了研究,并对其生态适应性进行了讨论。结果表明:(1)温度和光照变化对自然生境和温室收获种子的萌发率影响均不显... 通过显微结构及不同处理条件下种子萌发率的观察,对早春短命植物小拟南芥(Arabidopsis pumila)种子萌发特性及影响因素进行了研究,并对其生态适应性进行了讨论。结果表明:(1)温度和光照变化对自然生境和温室收获种子的萌发率影响均不显著,说明此种群在前期萌发阶段对光、温不敏感;(2)自然生境中采收的小拟南芥种子萌发率显著低于温室收获种子,说明环境条件的变化对短命植物种子的发育具有重要作用,可显著改变种子的萌发行为;(3)赤霉素使自然生境收获种子胚活性增强从而对萌发有较大促进作用,可使萌发率增加50%以上;(4)对种皮进行各种机械损伤处理使得种皮松弛或透气,可以显著提高自然生境种子的萌发率(超过70%);(5)盐和干旱胁迫对种子萌发均具有明显的抑制作用,但复水后部分被抑制种子可重新萌发,显示盐和干旱胁迫可导致种子产生浅度休眠。结合小拟南芥自然生存环境及本研究的结果,显示其种子萌发特性与生境具有高度适应性。 展开更多
关键词 短命植物 小拟南芥(Arabidopsis pumila) 生态适应性 盐胁迫 干旱胁迫
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薜荔(Ficus pumila L.)传粉的代价 被引量:13
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作者 李宏庆 陈勇 +1 位作者 鲁心安 马炜梁 《生态学杂志》 CAS CSCD 北大核心 1999年第3期66-69,共4页
种间关系中一方以自身生长过程中的一部分物质和能量为对方所利用的现象便是一个物种为对方付出的代价。在中性的种间关系中,两个物种彼此不受影响,无所谓代价;在偏性的种间关系中,受害者付出无谓的代价,受益者得到无偿的利益(如... 种间关系中一方以自身生长过程中的一部分物质和能量为对方所利用的现象便是一个物种为对方付出的代价。在中性的种间关系中,两个物种彼此不受影响,无所谓代价;在偏性的种间关系中,受害者付出无谓的代价,受益者得到无偿的利益(如寄主与寄生物、被捕食者与捕食者之间... 展开更多
关键词 薜荔 传粉 雄瘿株 榕小蜂
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薜荔榕小蜂(Blastophaga pumilae Hill)与薜荔(Ficus pumila L.)的共生关系 被引量:31
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作者 马炜梁 吴翔 《生态学报》 CAS CSCD 北大核心 1989年第1期9-14,共6页
榕属(Ficus)植物皆具隐头花序,我国有120种,分布很广。榕小蜂与榕树有着密切的共生关系。本文首次报道了我国此类动、植物的共生现象;发现了在同一个花序中雄花迟熟达一年的第一例植物;摸清了我国大陆新分布的薜荔榕小蜂的生活史;论述... 榕属(Ficus)植物皆具隐头花序,我国有120种,分布很广。榕小蜂与榕树有着密切的共生关系。本文首次报道了我国此类动、植物的共生现象;发现了在同一个花序中雄花迟熟达一年的第一例植物;摸清了我国大陆新分布的薜荔榕小蜂的生活史;论述了发育的同步性、结构与功能的统一性。其内容可作为了解榕属植物的隐头花序与榕小蜂特殊的形态结构、生活方式、传粉过程及体现在其中的生钫进化辩证法则的代表。因取材于分布最广的薜荔,敬为相关学科的教学、科研提供了生动易得的倒证。文末提出尚待解决的问题。 展开更多
关键词 薜荔榕小蜂 薜荔 共生
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不同光照条件下新疆小拟南芥(Arabidopsis Pumila)的表型可塑性研究 被引量:10
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作者 骆郴 刘彤 +2 位作者 魏鹏 宋红丽 赵峰侠 《石河子大学学报(自然科学版)》 CAS 2004年第2期149-153,共5页
田间观测同一区域不同光照条件下小拟南芥可塑性变化,研究表明:1)阴阳两地小拟南芥在株高和茎生叶数、叶重、花序重、茎重、莲座叶重等特征均达到显著差异,但是两地适合度差异不显著,显示出很强的可塑性;2)阴阳两地小拟南芥在叶重与茎... 田间观测同一区域不同光照条件下小拟南芥可塑性变化,研究表明:1)阴阳两地小拟南芥在株高和茎生叶数、叶重、花序重、茎重、莲座叶重等特征均达到显著差异,但是两地适合度差异不显著,显示出很强的可塑性;2)阴阳两地小拟南芥在叶重与茎生叶数、花序重与花序长、茎重与株高、地下重与主根长、角果重与角果数均表现为极显著相关,表现出很强的特征整合能力。根据现代植物可塑性研究成果,对新疆境内小拟南芥光适应性特点及进化趋势进行了分析。 展开更多
关键词 小拟南芥 适应性 可塑性 光照 表型整合
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锡盟沙地榆(Ulmus pumila L.var.sabulosa)遗传多样性的RAPD研究 被引量:4
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作者 李方祯 宛涛 +1 位作者 伊卫东 蔡萍 《中国农业科技导报》 CAS CSCD 2008年第3期71-76,共6页
应用随机扩增多态性DNA(RAPD)标记法对内蒙古浑善达克锡盟沙地榆6个居群和对照家榆4个居群的遗传多样性进行了研究,采用14条引物共获得118个位点,平均每个引物扩增条带数为8.4,个体水平上呈多态性的条带83条,占70.34%。根据遗传距离和... 应用随机扩增多态性DNA(RAPD)标记法对内蒙古浑善达克锡盟沙地榆6个居群和对照家榆4个居群的遗传多样性进行了研究,采用14条引物共获得118个位点,平均每个引物扩增条带数为8.4,个体水平上呈多态性的条带83条,占70.34%。根据遗传距离和聚类分析,锡盟沙地榆和对照家榆明显聚为两大类,表明经过漫长的进化,锡盟沙地榆产生并保留了较大的遗传变异,因此支持其作为家榆变种的结论。锡盟沙地榆各居群间遗传距离存在一定的差异,与其地理分布位置有极大的相关性,表明RAPD可用于锡盟沙地榆遗传多样性及系统学研究。 展开更多
关键词 RAPD 遗传多样性 锡盟沙地榆
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Effect of salt stress on activity of superoxide dismutase (SOD) in Ulmus pumila L. 被引量:32
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作者 SONG Fu-nan YANG Chuan-ping LIU Xue-mei LI Gong-bin 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期13-16,共4页
The injury tolerance of cell plasma membrane and the correlative enzymes activities of plasma-membrane protection system in the Ulmuspumila leaves treated by nine concentrations (0.3%, 0.6%, 0,9%, 1,2%, 1.5%, 1.8%, 2... The injury tolerance of cell plasma membrane and the correlative enzymes activities of plasma-membrane protection system in the Ulmuspumila leaves treated by nine concentrations (0.3%, 0.6%, 0,9%, 1,2%, 1.5%, 1.8%, 2,1%, 2.4%, 3.0%) of Na2CO3 and NaHCO3 mixtures were studied in a greenhouse of Northeast Forestry University, Harbin, China. The rate of electrolyte leakage (REL) and SOD (Superoxide dismutase) activity in leaves of different samples were determined. Results showed that the REL in leaves of U. pumila presented a slowly increasing trend at the salt concentrations less than 1.5%, which indicated that cell plasma membrane of U. pumila leaves had rather strong resistance to the injury of salt ion, and had a significant increase at the salt concentrations more than 1.5%. The SOD activities in leaves of U, pumila presented an increased trend at salt concentrations less than 1.5%, the growth of seedlings did not decline, and tress and leaves had no symptom of injury, while the salt concentrations exceeded 1.5%, SOD activities sharply decreased and REL increased promptly. 展开更多
关键词 Ulmus pumila Salt stress Rate of electrolyte leakage (REL) SOD
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Emissions of volatile organic compounds from heated needles and twigs of Pinus pumila 被引量:8
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作者 ZHAO Feng-jun SHU Li-fu WANG Qiu-hua WANG Ming-yu TIAN Xiao-ruiInstitute of Forest Ecology,Environment and Protection,Chinese Academy of Forestry Forest Protection Laboratory of State Forestry Administration,Beijing 100091,P.R.China. 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第2期243-248,共6页
A study was conducted to explore the mechanism that emissions of volatile organic compounds(VOC) from heated needles and twigs(200°C,within 15 min) of Pinus pumila affect fire behaviours using the technology ... A study was conducted to explore the mechanism that emissions of volatile organic compounds(VOC) from heated needles and twigs(200°C,within 15 min) of Pinus pumila affect fire behaviours using the technology of Thermal Desorption-Gas Chromatography-Mass Spectrometry(TD-GC-MS).The results indicated that the main components of VOC from heated needles and twigs are terpenoids.Most of these terpenoids are monoterpenes.Terpenoids account for 72.93% for the needles and 92.40% for the twigs of the total VOC,and their emission ratios are 61.200 μg·g-1 and 217.060 μg·g-1 respectively.Heated twigs can emit more terpenoids than heated needles because twigs had more volatile oils than needles.In actual fires,these large amounts of terpenoid emissions,especially the monoterpene emissions,have strong effects on fire behaviors that are not only in the initial stage but also in the fast propagation stage of fires.These flammable gases are capable of causing violent combustion and creating crown fires.In addition,if these gases accumulate in an uneven geographical area,there will be a possible for eruptive fires and/or fires flashover to occur. 展开更多
关键词 forest fire Pinus pumila volatile oil volatile organic compounds(VOC) TERPENOIDS
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A Breakdown of Obligate Mutualism on a Small Island: An Interspecific Hybridization between Closely Related Fig Species (Ficus pumila and Ficus thunbergii) in Western Japan 被引量:4
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作者 Lum Tsai Hiroshi Hayakawa +1 位作者 Tatsuya Fukuda Jun Yokoyama 《American Journal of Plant Sciences》 2015年第1期126-131,共6页
Ficus (Moraceae) is a well-known group with specific pollination mutualisms, and hybridization is considered to be rare. Here, we report the presence of interspecific hybrids between Ficus pumila L. and F. thunbergii ... Ficus (Moraceae) is a well-known group with specific pollination mutualisms, and hybridization is considered to be rare. Here, we report the presence of interspecific hybrids between Ficus pumila L. and F. thunbergii Maxim. on Okinoshima, a small island offshore of Shikoku, western Japan. AFLP (amplified fragment length polymorphism of genomic DNA) data suggested that more than one-fourth of individuals of morphological F. pumila were assigned as intermediate genotypes, suggesting hybrids. The hybridization between the two species was introgressive and unidirectional from F. thunbergii to F. pumila. The findings of this study, combined with other previous reports, suggest that the breakdown of mutualistic systems can occur in isolated populations such as those on islands. 展开更多
关键词 AFLP ISLAND HYBRIDIZATION FICUS pumila FICUS thunbergii WESTERN JAPAN
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重金属镍对白榆(Ulmus pumila L.)种子萌发及幼苗生长的影响 被引量:1
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作者 苗秀莲 刘传栋 吕艳伟 《种子》 北大核心 2015年第10期4-7,共4页
以我国常见的树木白榆种子为材料,在实验室内研究了不同浓度镍对种子萌发及幼苗生长的污染效应。结果表明:1mg/L浓度的Ni 2+能提升白榆种子的活力,但5,10mg/L浓度的Ni 2+已经对胚根生长有了显著抑制。50,100mg/L浓度的Ni 2+则对白... 以我国常见的树木白榆种子为材料,在实验室内研究了不同浓度镍对种子萌发及幼苗生长的污染效应。结果表明:1mg/L浓度的Ni 2+能提升白榆种子的活力,但5,10mg/L浓度的Ni 2+已经对胚根生长有了显著抑制。50,100mg/L浓度的Ni 2+则对白榆种子中后期的发芽和生长明显产生了伤害,导致成苗率极低或无法成苗。表明低浓度的Ni 2+促进白榆种子的萌发和生长,而高浓度的Ni 2+则有抑制作用。发芽抑制的阈值范围在10mg/L左右,胚根伸长抑制的阈值在0~5mg/L范围内,胚轴伸长抑制的阈值在5~50mg/L范围内。白榆施肥后土壤镍浓度应不超过5mg/kg。 展开更多
关键词 白榆 发芽
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Experimental Study on the Anti-inflammatory Effect of Ficus pumila L. 被引量:2
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作者 Chao ZENG Meiyuan LU +2 位作者 Tingting MO Bing WU Qingtong LAN 《Medicinal Plant》 CAS 2020年第4期26-29,共4页
[Objectives]To study the anti-inflammatory effects of extracts from different parts of Ficus pumila L.[Methods]Inflammatory models of xylene-induced ear swelling,glacial acetic acid-induced celiac capillary permeabili... [Objectives]To study the anti-inflammatory effects of extracts from different parts of Ficus pumila L.[Methods]Inflammatory models of xylene-induced ear swelling,glacial acetic acid-induced celiac capillary permeability and carrageenan-induced toe swelling were established to evaluate the effects of extracts from different parts of F.pumila L.on inflammation.The inflammatory model of ear swelling in mice with bilateral adrenalectomy induced by xylene was established to determine whether its anti-inflammatory effect depends on hypothalamus-pituitary-adrenal axis(HPAA)system.[Results]Compared with the blank control group,except that there was no statistical significance in the low dose group(P>0.05),the high and middle dose groups of extracts from different parts of F.pumila L.had significant inhibitory effects on xylene-induced ear swelling in mice.The high,middle and low dose groups of F.pumila L.extract could significantly increase the celiac capillary permeability of mice induced by glacial acetic acid,and significantly inhibit the toe swelling induced by carrageenan.Compared with the blank control group,the high and middle dose groups of extracts from different parts of F.pumila L.could significantly inhibit xylene-induced ear swelling and carrageenan-induced toe swelling in bilateral adrenalectomy mice.[Conclusions]The extracts from different parts of F.pumila L.had anti-inflammatory activity,and its anti-inflammatory effect was independent of hypothalamus-pituitary-adrenal axis(HPAA)system. 展开更多
关键词 Ficus pumila L. Anti-inflammatory effect Preliminary study
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Vegetation and Community Changes of Elm (Ulmus pumila) Woodlands in Northeastern China in 1983-2011 被引量:1
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作者 LIU Li WANG He +1 位作者 LIN Changcun WANG Deli 《Chinese Geographical Science》 SCIE CSCD 2013年第3期321-330,共10页
Elm (Ulmus pumila), widely distributed in the north temperate zone, contributes to a special savanna-like woodland in typical grassland region in the northeastern China. This woodland performs a variety of ecologica... Elm (Ulmus pumila), widely distributed in the north temperate zone, contributes to a special savanna-like woodland in typical grassland region in the northeastern China. This woodland performs a variety of ecological functions and environmental signifi- cance, such as decreasing soil erosion, stabilizing sand dunes, preserving species diversity. However, in the last approximate 30 years, the species composition, productivity and distribution area of elm woodland has decreased severely. A series of studies have been carried out to find out whether the climate changes or human disturbances caused the degradation of elm woodland and how these factors af- fected elm woodland. In this study, undisturbed, plowing and grazing elm woodland were investigated in 1983 and 2011 by using Point-Centered Quarter method. The relationship between vegetation changes and environmental factors was analyzed by Bray-Curtis ordination. The results show that in 2011, species diversity and understory productivity of undisturbed elm woodland decrease slightly compared to those of undisturbed elm woodland in 1983. However, nearly 60% of the species is lost in the plowing and grazing elm woodland relative to the species undisturbed elm woodland in 1983. Interestingly, plowing stimulates the growth of elm and certain understory species through furrowing soil and accelerating soil nutrient turnover rate. Grazing disturbance not only leads to species loss and productivity decrease, but also induces changes in elm growth (small, short and twisted). The mean age of the elm was 29 -4- 2 yr in undisturbed and plowing elm woodland, while only 15 yr in the grazing elm woodland. The results of Bray-Curtis ordination analysis show that all sample stands clustered to three groups: Group I including the undisturbed sample stands of 83UE (undisturbed elm wood- land in 1983) and l lUE (undisturbed elm woodland in 2011); Group II including sample stands of PE (elm woodland disturbed by plowing); Group III including samples stands of GE (elm woodland disturbed by grazing). The results indicate that the long time distur- bance of the plowing and grazing have converted elm woodland to different community types. Climate change is not the primary reason causing the degradation of elm woodland, but plowing and grazing disturbance. Both plowing and grazing decrease the vegetation composition and species diversity. Grazing further decreases vegetation productivity and inhibits the growth of elm tree. Therefore, we suggest that reasonable plowing and exclusive grazing would be favorable for future regeneration of degraded elm woodland. 展开更多
关键词 Elm (Ulmus pumila woodland species diversity plant distribution Bray-Curtis ordination
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Multiple Shoots Propagation with Bioreactor Culture of Labisia pumila(Bl.) F. Vill.
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作者 QI Wen-wen JIANG Yin-ji +3 位作者 LI Yong-yi MURTHY Hosakatte-niranjana CUI Xi-hua ZHANG Ji-de 《Agricultural Science & Technology》 CAS 2018年第3期31-39,共9页
This study was to establish the micropropagation system of Labisia pumila (Bl.) F. Vill. and explore the feasibility of mass production of its multiple shoots by bioreactor culture. [Method] The effects of cytokini... This study was to establish the micropropagation system of Labisia pumila (Bl.) F. Vill. and explore the feasibility of mass production of its multiple shoots by bioreactor culture. [Method] The effects of cytokinin or cytokinin/auxin mixture solution at different concentrations on its shoot growth and propagation by nodal segment culture were tested. In order to mass-proliferate its shoots, multiple shoots were suspension-cultured on Murashige and Skoog (MS) liquid medium in the bioreactor. [Results] Thidiazuron (TDZ) showed the highest cytokinin-like activity and the number of its shoots at the TDZ concentration of 0.1 mg/L was the maximum up to 21.5 shoots per explant, without the TDZ effect on shoot elongation, but zeatin signifcantly promoted the shoot elongation and each explant grew 6.8 relatively long shoots at 5.0 mg/L of zeatin. There was no signifcant effect on shoot propagation on induction medium supplemented with auxin. By inoculating 10 g/L (260 shoots) of multiple shoots into 3 L airlift bioreactor containing 2 L MS liquid medium supplemented with 0.1 mg/L TDZ for solution culture, 6 100 multiple shoots with a fresh weight of 183.13 g were harvested. After explant regeneration was conducted in MS solid medium, the regenerated plants were transplanted into flowerpot and the morphologically normal and healthy plants were obtained. [Conclusion] The development of bioreactor technology was conducive to the high efficiency propagation of L. pumila shoot. 展开更多
关键词 Labisia pumila Multiple shoot AUXIN BIOREACTOR CYTOKININ PROPAGATION
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红肉苹果(Malus pumila var.niedzwetzkyana)MpMYB30基因的克隆及表达载体的构建
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作者 展蔷 张计育 +3 位作者 佟兆国 董畅 章镇 渠慎春 《果树学报》 CAS CSCD 北大核心 2010年第4期483-489,共7页
MYB转录因子是植物转录因子中最大的家族之一,在转录调节中起着多方面的重要作用。实验利用RACE技术从野生红肉苹果(Malus pumila var.niedzwetzkyana Schneid.)中获得了MpMYB30的全长序列,利用生物信息学的方法对其蛋白进行了分析和预... MYB转录因子是植物转录因子中最大的家族之一,在转录调节中起着多方面的重要作用。实验利用RACE技术从野生红肉苹果(Malus pumila var.niedzwetzkyana Schneid.)中获得了MpMYB30的全长序列,利用生物信息学的方法对其蛋白进行了分析和预测并将其连接到pCAMBIA-S1300+植物表达载体中。结果表明,该基因全长为1661bp,推导的氨基酸序列经系统发育分析与葡萄MYB30及蓖麻MYB基因相似性最高,命名为MpMYB30,其N端含有2个约55个氨基酸组成的MYB特征结构域。该基因推导的MpMYB30蛋白的分子式为C1790H2794N538O584S12,相对分子质量为41579.8ku,等电点为6.30,不存在信号肽和跨膜区域,蛋白质结构以α螺旋为主。利用XbalⅠ和SacⅠ对重组质粒进行酶切,并将其连接到pCAMBIA-S1300+载体上,通过抗性筛选和PCR酶切检测,证实了MpMYB30基因已经构建到植物表达载体pCAMBIA-S1300+上。 展开更多
关键词 红肉苹果 MpMYB30 生物信息学 表达载体构建
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薜荔(Ficus Pumila L.)生物学及其开发利用的研究 被引量:2
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作者 赵运林 刘享平 +1 位作者 刘春元 曹晨忠 《湘潭师范学院学报(社会科学版)》 1991年第6期37-42,共6页
薜荔是分布于我国长江流域以南各省、区的一种常见植物。它既是一种常用的中药材,也是民间制作“凉份”的正宗原料,同时,还是重要的工业原料。本文就薜荔的生物学特性、物候学以及开发利用等方面进行阐述。
关键词 薜荔 生物学特性 物候学 开发利用
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OpNAC1 transcription factor regulates the biosynthesis of the anticancer drug camptothecin by targeting loganic acid O-methyltransferase in Ophiorrhiza pumila 被引量:3
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作者 Xiaolong Hao Can Wang +10 位作者 Wei Zhou Qingyan Ruan Chenhong Xie Yinkai Yang Chengyu Xiao Yan Cai Jingyi Wang Yao Wang Xuebin Zhang Itay Maoz Guoyin Kai 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2023年第1期133-149,共17页
Camptothecin(CPT) is an anticancer pentacyclic quinoline alkaloid widely used to treat cancer patients worldwide. However, the biosynthetic pathway and transcriptional regulation of camptothecin are largely unknown. O... Camptothecin(CPT) is an anticancer pentacyclic quinoline alkaloid widely used to treat cancer patients worldwide. However, the biosynthetic pathway and transcriptional regulation of camptothecin are largely unknown. Ophiorrhiza pumila, the herbaceous plant from the Rubiaceae family, has emerged as a model plant for studying camptothecin biosynthesis and regulation. In this study, a high-quality reference genome of O. pumila with estimated size of ~456.90Mb was reported, and the accumulation level of camptothecin in roots was higher than that in stems and leaves. Based on its spatial distribution in the plant, we examined gene functions and expression by combining genomics with transcriptomic analysis.Two loganic acid O-methyltransferase(OpLAMTs)were identified in strictosidine-producing plant O.pumila, and enzyme catalysis assays showed that OpLAMT1 and not OpLAMT2 could convert loganic acid into loganin. Further knock-out of OpL AMT1expression led to the elimination of loganin and camptothecin accumulation in O. pumila hairy roots.Four key residues were identified in OpLAMT1 protein crucial for the catalytic activity of loganic acid to loganin. By co-expression network, we identified a NAC transcription factor, OpNAC1, as a candidate gene for regulating camptothecin biosynthesis.Transgenic hairy roots and biochemical assays demonstrated that OpNAC1 suppressed OpLAMT1 expression. Here, we reported on two camptothecin metabolic engineering strategies paving the road for industrial-scale production of camptothecin in CPT-producing plants. 展开更多
关键词 camptothecin biosynthesis metabolic engineering strategies Ophiorrhiza pumila plant secondary metabolism transcriptional regulation
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白榆(Ulmus pumila L.)光驯化后的快速光曲线变化特征 被引量:16
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作者 韩炜 徐新文 +4 位作者 李利 李生宇 罗玉新 周艺 郭灵丽 《干旱区研究》 CSCD 北大核心 2010年第5期738-744,共7页
用饱和脉冲调幅式叶绿素荧光测定仪PAM-2100,分别测定了驯化于强光和弱光下的白榆(Ulmus pumila L.)叶片的快速光曲线。结果表明,驯化后的白榆叶片样品,其光合特征值发生明显改变。①强光驯化使得瞬时荧光Ft值升高,弱光驯化下非光化学... 用饱和脉冲调幅式叶绿素荧光测定仪PAM-2100,分别测定了驯化于强光和弱光下的白榆(Ulmus pumila L.)叶片的快速光曲线。结果表明,驯化后的白榆叶片样品,其光合特征值发生明显改变。①强光驯化使得瞬时荧光Ft值升高,弱光驯化下非光化学淬灭系数NPQ高于强光驯化值;②弱光驯化后,吸收能量的比例参数Y(Ⅱ)大大减小,主动散失能量的能力参数Y(NPQ)增加,但是对于结构性保护能力参数Y(NO)影响不大;③强光驯化后的白榆叶片的最大电子传递速率rETRmax远大于弱光驯化后的相应值,相应的初始斜率α和半饱和光强Ik也具有类似的规律。市内环境的光合有效辐射不会对白榆造成光合机构的损伤,强光驯化更有利于白榆的光合作用;在干旱区植物中,白榆具有较强抗性和竞争力;市内绿化规划时,建议将白榆种植在阳光直射处,既可以充分发挥白榆的强光抗性,又可以为一些阴生绿化植物减少阳光直射伤害。 展开更多
关键词 白榆(Ulmus pumila L.) 叶绿素荧光 光驯化 快速光曲线 拟合 能量 分配策略
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浑善达克沙地榆树(Ulmus pumila)种群结构和动态特征 被引量:10
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作者 张志永 杨晓晖 +2 位作者 张晓 刘艳书 时忠杰 《中国沙漠》 CSCD 北大核心 2018年第3期524-534,共11页
榆树(Ulmus pumila)疏林是一种以榆树为优势种的疏林草地类型,榆树的存在对于维持区域生态稳定性具有重要意义。采用空间代替时间的方法,通过编制静态生命表,绘制存活、死亡率和消失率曲线,同时应用生存函数、积累死亡率函数、死亡密度... 榆树(Ulmus pumila)疏林是一种以榆树为优势种的疏林草地类型,榆树的存在对于维持区域生态稳定性具有重要意义。采用空间代替时间的方法,通过编制静态生命表,绘制存活、死亡率和消失率曲线,同时应用生存函数、积累死亡率函数、死亡密度函数和危险率函数分析了浑善达克沙地榆树的种群结构和发展动态。结果表明:在4个区域中,榆树的种群密度、胸径、树高、冠幅具有一定的差异性,东部区域的种群密度最大,胸径、树高、冠幅最小。榆树种群的年龄结构呈现2个峰值,存在断层问题。榆树种群整体呈现前期锐减、中期稳定、后期衰退的动态特征。前期数量锐减可能是自然灾害、土地沙化、牲畜啃食以及人为破坏等干扰活动综合作用的结果,后期衰退可能是榆树个体间对水分、光照、养分等生存因子相互竞争的结果。本研究区域存在数量较多的榆树幼苗,在合理的经营管理措施下,榆树可以实现种群的自主更新。该过程可能需要至少30a的时间,需要长期稳定的政策支持。 展开更多
关键词 榆树(Ulmus pumila) 年龄结构 静态生命表 存活曲线 种群更新
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HPS生物有机肥显著提升阿克苏地区苹果园土壤和叶片养分含量及果实品质
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作者 魏智博 周高兴 +1 位作者 李欣 王新建 《湖北农业科学》 2024年第9期47-51,88,共6页
以苹果(Malus pumila Mill.)为试验材料,以HPS生物有机肥为研究对象,设置2个HPS生物有机肥处理,施肥量分别为24、15 kg/株,并减施50%的化肥,同时以常规施肥管理为对照(CK),考察了HPS生物有机肥对苹果园土壤养分及苹果叶片养分和果实品... 以苹果(Malus pumila Mill.)为试验材料,以HPS生物有机肥为研究对象,设置2个HPS生物有机肥处理,施肥量分别为24、15 kg/株,并减施50%的化肥,同时以常规施肥管理为对照(CK),考察了HPS生物有机肥对苹果园土壤养分及苹果叶片养分和果实品质的影响。结果表明,与CK相比,2个HPS生物有机肥处理土壤养分含量、苹果叶片养分含量及果实品质均有提升,且以施用24 kg/株HPS生物有机肥处理最高,其土壤碱解氮、速效磷、速效钾含量及叶片全氮、全磷、全钾含量显著增加(P<0.05),果实单果重和纵径显著增加(P<0.05),可溶性固形物、可溶性糖含量和维生素C含量也显著增加(P<0.05)。这说明在化肥减施下施用HPS生物有机肥可提升土壤养分、叶片养分含量及果实品质,且以24 kg/株的施用量较佳。 展开更多
关键词 HPS生物有机肥 土壤养分 苹果(Malus pumila Mill.) 叶片养分 果实品质 阿克苏地区
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苹果果胶的理化特性、抗氧化及降血脂作用研究
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作者 卢泳强 周朝曦 +4 位作者 张丽丽 俞永婷 娜迪热木·肖克拉提 王新玲 丛媛媛 《食品与发酵工业》 CAS CSCD 北大核心 2024年第7期61-68,共8页
探究苹果果胶(Malus pumila pectin,MP)的理化性质、抗氧化及降血脂作用。利用高效凝胶渗透色谱法测定其分子质量分布,并测定其半乳糖醛酸含量、酯化度、单糖组成等理化性质,采用红外光谱法推测可能存在的结构;体外抗氧化实验评价其抗... 探究苹果果胶(Malus pumila pectin,MP)的理化性质、抗氧化及降血脂作用。利用高效凝胶渗透色谱法测定其分子质量分布,并测定其半乳糖醛酸含量、酯化度、单糖组成等理化性质,采用红外光谱法推测可能存在的结构;体外抗氧化实验评价其抗氧化能力。通过高脂饮食诱导建立高脂血症大鼠模型,利用MP灌胃干预,测定各组大鼠体质量、血清脂质含量、血清抗氧化指标,观察肝脏病理变化情况。结果表明,MP分子质量主要分布在2~45 kDa,糖醛酸含量为66.51%、酯化度为13.43%,主要由鼠李糖、半乳糖醛酸、葡萄糖、半乳糖和阿拉伯糖组成,摩尔比为0.60∶9.35∶0.58∶1.14∶0.96;红外光谱分析表明MP具有典型的多糖类特征吸收峰,含有吡喃糖环,且具有一定的抗氧化活性。体内降血脂实验表明,MP能抑制高脂饮食大鼠体重的增长(P<0.05),降低因高脂饮食导致的血清甘油三酯、总胆固醇和低密度脂蛋白胆固醇水平的增加(P<0.05),升高高密度脂蛋白胆固醇水平(P<0.05),提高大鼠抗氧化体系相关物质的水平(P<0.05),降低丙二醛水平(P<0.05),减轻高脂饮食导致的肝脏损伤。因此,该实验用MP是一种低酯化度的酸性多糖,抗氧化能力强,具有较好的降血脂活性。该研究结果旨在为商品化MP理化性质和生物活性的系统研究提供数据支持,对MP开发天然功能性产品提供思路。 展开更多
关键词 苹果 果胶 理化性质 抗氧化 降血脂
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