共查询到20条相似文献,搜索用时 155 毫秒
1.
为进一步研究淀粉分支酶(Starch branching enzyme,SBE)在青稞叶片淀粉代谢中的作用,以青稞品种喜马拉雅2号和康青1号为材料,通过同源克隆技术分离 SBEⅡa基因,并对分离得到的 SBEⅡa基因进行生物信息学分析,同时利用实时荧光定量PCR(qRT-PCR)技术和淀粉分支酶活性测定试剂盒分析了在高温、低温和盐胁迫条件下 SBEⅡa基因的表达情况和SBEⅡa蛋白酶活性的变化情况。结果表明,从喜马拉雅2号和康青1号克隆得到的 SBEⅡa基因ORF区为2466 bp,编码821个氨基酸。生物信息学分析表明,该基因编码的蛋白质分子量为92.09 kDa,预测等电点(pI)为5.4,是酸性蛋白;该蛋白酶的不稳定系数为38.03,属于稳定蛋白;参试材料与大麦的亲缘关系最近,与细江蓠的亲缘关系最远。qRT-PCR和蛋白酶活性测定结果表明, SBEⅡa基因在不同环境下表达水平和SBEⅡa蛋白酶活性变异具有高度的正相关性,在不同环境和不同材料之间没有明显差异。 相似文献
2.
正八、殖民地时代的茶叶庄园生活柯科斯沃尔德茶叶庄园(Kirkoswald Bungalow)斯里兰卡以其旖旎的海滨风光、历史悠久的古城、丰富的自然遗产、独特的民族文化吸引世界各地游客;而中部高地山区,则以陡峭险峻的山川峡谷、漫山翠绿的茶园、云雾缭绕的原始丛林、奔腾流淌的小河、飞流直下的瀑布、凉爽宜人的气候、丰富多彩和多样化的植物和动物群落等美丽的自然景色成为斯里兰卡最吸引人的观光景点。同时,参观茶园和茶厂、了解红茶加工过程、品尝国际知名的红茶成为在中央高地山区旅游时必不可少的内容。从首都科伦坡前往中部山区的公路和19世纪修筑的铁路线也穿越在翠绿的茶园中,使游客更增添了许多新的体验。参观游览茶园,不仅使游客更多了解锡兰红茶的生产、加工和品质。同时 相似文献
3.
4.
农户对水稻品种的采用和认知——来自三省农户的调查 总被引:7,自引:0,他引:7
本文在实地调查资料的基础上对中国南方稻农对水稻品种的采用现状和对水稻品种的认识进行了描述,并分析了对农户水稻品种采用的影响因素,主要得出了如下结论:1、不同地区的农户对品种性状的要求是不同的;2、边缘地区农户的品种的需求在一定程度上被忽视;3、农户对品种性状的认知是有限的,这种有限的认知影响了农户对品种的最终采用。政府手应该加强对这种信息传播渠道的建设,育种单位应该根据农户的需求来培育适合当地种植的品种,这一点在被边缘化的山区尤为必要, 相似文献
5.
小麦籽粒发育时期Puroindolines蛋白与硬度的关系 总被引:1,自引:0,他引:1
为探讨Puroindolines蛋白的表达特点与籽粒硬度的关系,采用改进的SDS-PAGE凝胶分析了不同硬度小麦品种的籽粒在各个发育时期Puroindolines蛋白的表达.结果表明,不同硬度的小麦籽粒中总Puroindolines(PinA和PinB)蛋白的表达量差异不大,但与胚乳淀粉颗粒结合的Puroindolines蛋白量差异非常明显:在籽粒发育的不同时期,软质小麦籽粒淀粉粒表面结合的Puroindolines蛋白量显著高于硬质小麦;基因型同为野生型但硬度有差异的品种,籽粒较软的材料其淀粉粒表面结合的Puroindolines蛋白量也明显高于较硬的材料,说明该蛋白的结合特性是决定籽粒硬度的直接原因.结果还表明,胚乳中水溶性戊聚糖与籽粒硬度关系密切. 相似文献
6.
实践证明,棉农是国家实施棉花良种补贴的最大受益者,实现了棉花良种补贴的主要目的.有人对棉花良种补贴持有不同的态度,是因为棉农、种子企业和基层农技推广部门等相对独立的利益主体,均以从项目实施中获利多少来评价政策的优劣.棉种市场混乱是制约项目实施的关键因素,要提高项目实施水平,必须采取综合措施,重点是整治棉种市场,简化补贴操作程序. 相似文献
7.
8.
新年伊始,万象更新。评茶实验室专栏已经走过了一个春秋。在这蹒跚学步的一年,我们得到了行业内外广大读者的大力支持和帮助。结合大家提出的宝贵意见和栏目一年的自身实践,评茶实验室将在新的一年以全新的形式——茗茶尚品和大家一同识茶、品茶。在这寒冷的冬季,让我们从红茶的阵阵暖香开始…… 相似文献
9.
10.
11.
Boonyakorn Boonsri Kiattawee Choowongkomon Buabarn Kuaprasert Thanvarin Thitiphatphuvanon Kittiya Supradit Apinya Sayinta Jinchutha Duangdara Tawut Rudtanatip Kanokpan Wongprasert 《Marine drugs》2021,19(5)
Sulfated galactans (SG) isolated from red alga Gracilaria fisheri have been reported to inhibit the growth of cholangiocarcinoma (CCA) cells, which was similar to the epidermal growth factor receptor (EGFR)-targeted drug, cetuximab. Herein, we studied the anti-cancer potency of SG compared to cetuximab. Biological studies demonstrated SG and cetuximab had similar inhibition mechanisms in CCA cells by down-regulating EGFR/ERK pathway, and the combined treatment induced a greater inhibition effect. The molecular docking study revealed that SG binds to the dimerization domain of EGFR, and this was confirmed by dimerization assay, which showed that SG inhibited ligand-induced EGFR dimer formation. Synchrotron FTIR microspectroscopy was employed to examine alterations in cellular macromolecules after drug treatment. The SR-FTIR-MS elicited similar spectral signatures of SG and cetuximab, pointing towards the bands of RNA/DNA, lipids, and amide I vibrations, which were inconsistent with the changes of signaling proteins in CCA cells after drug treatment. Thus, this study demonstrates the underlined anti-cancer mechanism of SG by interfering with EGFR dimerization. In addition, we reveal that FTIR signature spectra offer a useful tool for screening anti-cancer drugs’ effect. 相似文献
12.
13.
The effects of 3 different methods for removing the initial air on the properties of fermented plant beverages produced from phom-nang seaweed (Gracilaria fisheri) and wild forest noni (Morinda coreia Ham.) were investigated. Only method M which covered the space above the fermentation liquid with a water filled plastic bag produced no surface film of yeast, had the highest acidity and also antibacterial activity from both plants after 90 days of fermentation. However, the yeast count still exceeded the standard guidelines for plant beverages. The fermented beverage from wild forest noni showed more antibacterial activity against 3 of 4 pathogenic bacteria tested than that from the phomnang seaweed, probably for its higher levels of acidity and ethanol content. Lactic Acid Bacteria (LAB) isolated from the fermentation samples from days 1-5 using the method M from both fermented plant beverages were Leuconostoc mesenteroides supsp. mesenteroides and Leu. mesenteroides subsp. dextranicum while presence of Lactobacilus plantarum was only recorded at days 4-5 in the wild forest noni beverage. From days 6-14 the isolates were Lactobacillus plantarum, Lactobacillus fermentum and Lactobacillus brevis from wild forest noni beverage, whereas only L. brevis was not detected in the seaweed beverage. During days 21-45 both beverages had a similar LAB population of L. plantarum and L. brevis while L. coryniformis was only found in the wild forest noni beverage. Between days 60-90 in both plant beverages only L. plantarum and Lactobacillius sp. were detected. 相似文献
14.
Renan O. Silva Ana Paula M. Santana Nathalia S. Carvalho Talita S. Bezerra Camila B. Oliveira Samara R. B. Damasceno Luciano S. Chaves Ana Lúcia P. Freitas Pedro M. G. Soares Marcellus H. L. P. Souza André Luiz R. Barbosa Jand-Venes R. Medeiros 《Marine drugs》2012,10(12):2618-2633
Red seaweeds synthesize a great variety of sulfated galactans. Sulfated polysaccharides (PLSs) from seaweed are comprised of substances with pharmaceutical and biomedical potential. The aim of the present study was to evaluate the protective effect of the PLS fraction extracted from the seaweed Gracilaria birdiae in rats with naproxen-induced gastrointestinal damage. Male Wistar rats were pretreated with 0.5% carboxymethylcellulose (control group—vehicle) or PLS (10, 30, and 90 mg/kg, p.o.) twice daily (at 09:00 and 21:00) for 2 days. After 1 h, naproxen (80 mg/kg, p.o.) was administered. The rats were killed on day two, 4 h after naproxen treatment. The stomachs were promptly excised, opened along the greater curvature, and measured using digital calipers. Furthermore, the guts of the animals were removed, and a 5-cm portion of the small intestine (jejunum and ileum) was used for the evaluation of macroscopic scores. Samples of the stomach and the small intestine were used for histological evaluation, morphometric analysis and in assays for glutathione (GSH) levels, malonyldialdehyde (MDA) concentration, and myeloperoxidase (MPO) activity. PLS treatment reduced the macroscopic and microscopic naproxen-induced gastrointestinal damage in a dose-dependent manner. Our results suggest that the PLS fraction has a protective effect against gastrointestinal damage through mechanisms that involve the inhibition of inflammatory cell infiltration and lipid peroxidation. 相似文献
15.
Silva RO dos Santos GM Nicolau LA Lucetti LT Santana AP Chaves Lde S Barros FC Freitas AL Souza MH Medeiros JV 《Marine drugs》2011,9(11):2188-2200
The aim of the present study was to investigate the gastroprotective activity of a sulfated-polysaccharide (PLS) fraction extracted from the marine red algae Gracilaria caudata and the mechanism underlying the gastroprotective activity. Male Swiss mice were treated with PLS (3, 10, 30 and 90 mg·kg(-1), p.o.), and after 30 min, they were administered 50% ethanol (0.5 mL/25 g(-1), p.o.). One hour later, gastric damage was measured using a planimeter. Samples of the stomach tissue were also obtained for histopathological assessment and for assays of glutathione (GSH) and malondialdehyde (MDA). Other groups were pretreated with l-NAME (10 mg·kg(-1), i.p.), dl-propargylglycine (PAG, 50 mg·kg(-1), p.o.) or glibenclamide (5 mg·kg(-1), i.p.). After 1 h, PLS (30 mg·kg(-1), p.o.) was administered. After 30 min, ethanol 50% was administered (0.5 mL/25 g(-1), p.o.), followed by sacrifice after 60 min. PLS prevented-ethanol-induced macroscopic and microscopic gastric injury in a dose-dependent manner. However, treatment with l-NAME or glibenclamide reversed this gastroprotective effect. Administration of propargylglycine did not influence the effect of PLS. Our results suggest that PLS has a protective effect against ethanol-induced gastric damage in mice via activation of the NO/K(ATP) pathway. 相似文献
16.
Zahira Belattmania Sanaa Bhaby Amal Nadri Khaoulaa Khaya Fouad Bentiss Charafeddine Jama Abdeltif Reani Vitor Vasconcelos Brahim Sabour 《Marine drugs》2021,19(12)
Agar is a sulfated polysaccharide extracted from certain marine red algae, and its gel properties depend on the seaweed source and extraction conditions. In the present study, the seaweed Gracilaria gracilis (Gracilariales, Rhodophyta) from Dakhla (Moroccan Atlantic Coast) was investigated for its agar content, structure, and gel properties. The agar yields of G. gracilis were 20.5% and 15.6% from alkaline pretreatment and native extraction, respectively. Agar with alkaline pretreatment showed a better gelling property supported by higher gel strength (377 g·cm−2), gelling (35.4 °C), and melting (82.1 °C) temperatures with a notable increase in 3,6-anhydro-galactose (11.85%) and decrease in sulphate (0.32%) contents. The sulfate falling subsequent to alkaline pretreatment was verified through FT-IR spectroscopy. The 13C NMR spectroscopy showed that alkaline-pretreated agar has a typical unsubstituted agar pattern. However, native agar had a partially methylated agarose structure. Overall, this study suggested the possibility of the exploitation of G. gracilis to produce a fine-quality agar. Yet, further investigation may need to determine the seasonal variability of this biopolymer according to the life cycle of G. gracilis. 相似文献
17.
Joo Cotas Diana Pacheco Glacio Souza Araujo Ana Valado Alan T. Critchley Leonel Pereira 《Marine drugs》2021,19(3)
To exploit the nutraceutical and biomedical potential of selected seaweed-derived polymers in an economically viable way, it is necessary to analyze and understand their quality and yield fluctuations throughout the seasons. In this study, the seasonal polysaccharide yield and respective quality were evaluated in three selected seaweeds, namely the agarophyte Gracilaria gracilis, the carrageenophyte Calliblepharis jubata (both red seaweeds) and the alginophyte Sargassum muticum (brown seaweed). It was found that the agar synthesis of G. gracilis did not significantly differ with the seasons (27.04% seaweed dry weight (DW)). In contrast, the carrageenan content in C. jubata varied seasonally, being synthesized in higher concentrations during the summer (18.73% DW). Meanwhile, the alginate synthesis of S. muticum exhibited a higher concentration (36.88% DW) during the winter. Therefore, there is a need to assess the threshold at which seaweed-derived polymers may have positive effects or negative impacts on human nutrition. Furthermore, this study highlights the three polymers, along with their known thresholds, at which they can have positive and/or negative health impacts. Such knowledge is key to recognizing the paradigm governing their successful deployment and related beneficial applications in humans. 相似文献
18.
Monsuang Yangthong Nongporn Hutadilok-Towatana Wutiporn Phromkunthong 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(3):218-223
The aqueous extracts of four marine algae, Caulerpa racemosa var. macrophysa, Gracilaria tenuistipitata var. tenuistipitata, Sargassum sp., and Ulva lactuca, from the coastal areas in Southern Thailand, were prepared by boiling dried seaweed powder in water for 3 h, and by autoclaving
each sample at 120 °C for 3 h. They were then freeze-dried and evaluated for their antioxidant activities using DPPH (1, 1-diphenyl-2-picrylhydrazyl),
hydroxyl radical (OH•) and superoxide anion (O2•−) scavenging assays. Boiling extracts of the seaweeds, except C. racemosa, were found to have higher total phenolic contents (TPC) than those obtained from the autoclave method. The antioxidant results
also showed that O2•− scavenging activity existed only in the boiling extracts of C. racemosa, G. tenuistipitata, and U. lactuca. In DPPH and OH• assays, however, almost all the boiling extracts were less active than the autoclave ones. Among the four alga species, Sargassum sp. was the most active. Both extracts of this seaweed had the highest TPC and also displayed the strongest DPPH• and OH• inhibitory activities. A strong positive-correlation between the antioxidant potency and TPC of the autoclave extracts was
found, while for the boiling extracts such relation was very weak. This result thus reflected that in addition to the phenolic
compounds, there might be some other active components present in these extracts involved in the antioxidant activity. 相似文献
19.
Xiaoshan Long Xiao Hu Shaobo Zhou Huan Xiang Shengjun Chen Laihao Li Shucheng Liu Xianqing Yang 《Marine drugs》2022,20(1)
Gracilaria lemaneiformis polysaccharide (GLP) exhibits good physiological activities, and it is more beneficial as it is degraded. After its degradation by hydrogen peroxide combined with vitamin C (H2O2-Vc) and optimized by Box–Behnken Design (BBD), a new product of GLP-HV will be generated. While using GLP as control, two products of GLP-H (H2O2-treated) and GLP-V (Vc-treated) were also produced. These products chemical characteristics (total sugar content, molecular weight, monosaccharide composition, UV spectrum, morphological structure, and hypolipidemic activity in vitro) were assessed. The results showed that the optimal conditions for H2O2-Vc degradation were as follows: H2O2-Vc concentration was 18.7 mM, reaction time was 0.5 h, and reaction temperature was 56 °C. The total sugar content of GLP and its degradation products (GLP-HV, GLP-H and GLP-V) were more than 97%, and their monosaccharides are mainly glucose and galactose. The SEM analysis demonstrated that H2O2-Vc made the structure loose and broken. Moreover, GLP, GLP-HV, GLP-H, and GLP-V had significantly inhibition effect on α-glucosidase, and their IC50 value were 3.957, 0.265, 1.651, and 1.923 mg/mL, respectively. GLP-HV had the best inhibition effect on α-glucosidase in a dose-dependent manner, which was the mixed type of competitive and non-competitive. It had a certain quenching effect on fluorescence of α-glucosidase, which may be dynamic quenching. 相似文献
20.
Camila Lehnhardt Pires Selma Dzimidas Rodrigues Daniel Bristot Henrique Hessel Gaeta Daniela de Oliveira Toyama Wladimir Ronald Lobo Farias Marcos Hikari Toyama 《Marine drugs》2013,11(3):934-943
The sulfated polysaccharides from Solieria filiformis (Sf), Botryocladia occidentalis (Bo), Caulerpa racemosa (Cr) and Gracilaria caudata (Gc) were extracted and extensively purified. These compounds were then subjected to in vitro assays to evaluate the inhibition of these polysaccharides on the growth of Leishmania (L.) amazonensis promastigotes. Under the same assay conditions, only three of the four sulfated polysaccharides were active against L. amazonensis, and the polysaccharide purified from Cr was the most potent (EC50 value: 34.5 μg/mL). The polysaccharides derived from Bo and Sf demonstrated moderate anti-leishmanial activity (EC50 values of 63.7 μg/mL and 137.4 μg/mL). In addition, we also performed in vitro cytotoxic assays toward peritoneal macrophages and J774 macrophages. For the in vitro cytotoxicity assay employing J774 cells, all of the sulfated polysaccharides decreased cell survival, with CC50 values of 27.3 μg/mL, 49.3 μg/mL, 73.2 μg/mL, and 99.8 μg/mL for Bo, Cr, Gc, and Sf, respectively. However, none of the sulfated polysaccharides reduced the cell growth rate of the peritoneal macrophages. These results suggest that macroalgae contain compounds with various chemical properties that can control specific pathogens. According to our results, the assayed sulfated polysaccharides were able to modulate the growth rate and cell survival of Leishmania (L.) amazonensis promastigotes in in vitro assays, and these effects involved the interaction of the sulfated polysaccharides on the cell membrane of the parasites. 相似文献