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971.
    
This is the first attempt to evaluate the impact of four salinity levels on the color parameters, pigments, polyphenols, flavonoids, and antioxidant capacities of four promising A. lividus genotypes. The color parameters, such as the yellowness/blueness (b*) and the chroma (C*); the antioxidant components, such as the polyphenols and flavonoids; and the antioxidant capacities of the leaves were remarkably increased by 39, 1, 5, 10 and 43%, respectively, at 50 mM of NaCl, and by 55, 5, 60, 34, 58 and 82%, respectively, at 100 mM NaCl concentrations. The green tower and SA6 genotypes were identified as tolerant varieties. The total phenolic content (TPC) and the total flavonoid content (TFC) played vital roles in scavenging reactive oxygen species (ROS), and they would be beneficial for the human diet and would serve as good antioxidants for the prevention of aging, and they are also essential to human health. A correlation study revealed the strong antioxidant capacities of the pigments and antioxidant components that were studied. It was revealed that A. lividus could tolerate a certain level of salinity stress without compromising the antioxidant quality of the final product. Taken together, our results suggest that A. lividus could be a promising alternative crop for farmers, especially in saline-prone areas in the tropical and subtropical regions.  相似文献   
972.
    
Thrombocytopenia is a clinical manifestation that refers to the low platelet count, i.e., <150 × 103/μL, of blood, resulting in imbalanced hemostasis, which leads to several fatal complications. The causative factors vary greatly, but, as a consequence, they interfere with platelet production and promote destruction, leading to death. Carica papaya leaf has unique therapeutic and medicinal characteristics against thrombocytopenia, and this is supported by scientific studies. Secondary metabolites and minerals in the leaf, such as carpaine and quercetin, promote platelet production, inhibit platelet destruction, and maintain platelet membrane through gene expression activity and the ceasing of viral proteases, respectively. This review explores the scientific studies that support the role of papaya leaf in the form of juice, extract, or powder against thrombocytopenia through animal modeling and clinical trials. Phytochemical profiles of C. papaya leaf revealed the presence of flavonoids, alkaloids, phenols, cardiac glycosides, tannins, terpenes, and saponins, which impart therapeutic potential to the leaf. The therapeutic benefits of the leaf include immunomodulatory, antiviral, antidiabetic, anticancer, antimalarial, antiangiogenic, antibacterial, and antioxidant activities. Several conducted scientific research studies have proved the efficacy of C. papaya leaf against thrombocytopenia, expanding the implication of natural sources to eradicate numerous ailments.  相似文献   
973.
    
In this study, rosemary leaf extract was effectively used to synthesize cobalt oxide nanoparticles (Co3O4 NPs) using a rapid, low-cost, and environmentally friendly approach. The prepared Co3O4 NPs were examined using various analytical techniques. However, UV spectrum analysis displayed two sharp absorption peaks at ~350 and 745 nm. The dynamic light scattering and zeta potential measurements were used to evaluate the particle size and the effective stabilization of the synthetic nanoparticles in the suspensions. A semi-triangular pyramidal shape of the Co3O4 NPs with a wide particle-size distribution could be observed in the scanning electron microscopy images. The energy-dispersive X-ray spectrum confirmed their successful synthesis, as the experimental atomic percentages agreed with the theoretical values. Moreover, X-ray diffraction analysis revealed that the synthesized Co3O4 NPs had a cubic crystalline structure corroborating that of theoretical Co3O4. Additionally, the Co3O4 NPs were not toxic at ≤62.5 µg/mL for Hep G2 and at ≤31.25 µg/mL for Mcf7. Therefore, these unique environmentally friendly Co3O4 NPs at this safe concentration could be studied in the future for their therapeutic activity.  相似文献   
974.
    
Background: The present study investigated the antifungal activity and mode of action of four Olea europaea leaf extracts, Thymus vulgaris essential oil (EO), and Boswellia carteri EO against Fusarium oxysporum. Methods: Fusarium oxysporum lactucae was detected with the internal transcribed spacer (ITS) region. The chemical compositions of chloroform and dichloromethane extracts of O. europaea leaves and T. vulgaris EO were analyzed using GC-MS analysis. In addition, a molecular docking analysis was used to identify the expected ligands of these extracts against eleven F. oxysporum proteins. Results: The nucleotide sequence of the F. oxysporum lactucae isolate was deposited in GenBank with Accession No. {\"type\":\"entrez-nucleotide\",\"attrs\":{\"text\":\"MT249304.1\",\"term_id\":\"1824655600\",\"term_text\":\"MT249304.1\"}}MT249304.1. The T. vulgaris EO, chloroform, dichloromethane and ethanol efficiently inhibited the growth at concentrations of 75.5 and 37.75 mg/mL, whereas ethyl acetate, and B. carteri EO did not exhibit antifungal activity. The GC-MS analysis revealed that the major and most vital compounds of the T. vulgaris EO, chloroform, and dichloromethane were thymol, carvacrol, tetratriacontane, and palmitic acid. Moreover, molecular modeling revealed the activity of these compounds against F. oxysporum. Conclusions: Chloroform, dichloromethane and ethanol, olive leaf extract, and T. vulgaris EO showed a strong effect against F. oxysporum. Consequently, this represents an appropriate natural source of biological compounds for use in healthcare. In addition, homology modeling and docking analysis are the best analyses for clarifying the mechanisms of antifungal activity.  相似文献   
975.
本文对青海巴毅克拉山、阿尼玛卿山产五种柳属植物的叶片进行了解剖学研究,结果表明:五种高山柳属植物的叶均为异面叶,具较厚的角质膜,上表皮角质膜一般较下表角质膜厚0.5-μm;栅栏组织较发达,一般由2-3层细胞构成;下表皮为双层细胞组成组成的复表皮,有异染色薄壁细胞构成的维管束鞘,维管束单个,维管速近轴面有5-6层的厚角细胞,远轴面也有多层的有细胞。  相似文献   
976.
竹子发育生物学研究进展   总被引:1,自引:0,他引:1  
尽管人们利用竹子资源的历史可以追溯到7 000年以前,但直到18世纪后期人们才真正认识到竹子是禾本科植物中一个特殊的类群。现代植物分类的奠基人林奈在《植物种志》(Species Plantarum)一书中,还只是将全世界的竹子归为芦竹属的一个种Arundo arbor,直到1789年,竹子才从芦竹属(Arundo)独立出来,成立了簕竹属(Bambusa)。自竹类被认识到有别于其他禾本科植物至今,有关竹子的形态学、解剖学、系统分类学、生理学、生态学、细胞学、遗传学以及分子生物学等,已经有大量的研究报道,但对竹类植物各个器官的发生、发育和衰老过程尚缺乏系统的研究。笔者对竹类植物的根、地下茎、竹秆、竹叶和生殖器官发育生物学的研究进行了回顾与总结,分析了目前竹子发育生物学领域有待继续深入研究的问题。建议竹子发育生物学的研究应关注细胞分裂、分化和形态建成的全过程,明确整个过程中生理生化指标的变化规律,进而揭示植物发育全过程每个环节的信号转导途径和基因调控网络。  相似文献   
977.
为了深入地了解热带山地雨林原始林与次生林叶氨基酸对氮添加的响应和适应机制, 以海南尖峰岭热带山地雨林原始林和次生林的林下常见植物为研究对象, 通过设置对照CK (0 kg N/(ha·a))、中氮添加M (50kg N/(ha·a))和高氮添加H (100 kg N/(ha·a)) 3种氮添加处理的实验, 探究氮添加对林下灌木叶片氨基酸含量的影响。实验结果表明, 无氮添加时, 原始林与次生林的总氨基酸含量和水解氨基酸含量无显著差异, 原始林游离氨基酸总含量显著高于次生林; 中氮添加时, 次生林林下灌木叶氨基酸含量的响应程度高于原始林; 高氮添加时, 次生林与原始林林下灌木水解氨基酸的响应程度无显著差异, 原始林林下灌木游离氨基酸的响应程度高于次生林。  相似文献   
978.
【目的】探究叶片喷施不同质量浓度的多效唑(PP333)、矮壮素(CCC)、烯效唑(S3307)对板栗苗枝条生长动态及叶片内非结构性碳水化合物(NSC)[可溶性糖(SS)和淀粉(ST)]含量的影响,为板栗化学调控提供理论依据。【方法】以备选砧木3年生板栗‘燕山早丰’(Castanea mollissima‘Yanshanzaofeng’)苗为试验材料,选择15%多效唑可湿性粉剂、50%矮壮素水剂、5%烯效唑可湿性粉剂配置溶液,在花芽分化期选择天气晴朗无风的早晨分别喷施多效唑(50、100、150 mg/L)、矮壮素(100、150、200 mg/L)和烯效唑(30、60、90 mg/L),以喷清水为对照(CK),各处理进行整株喷施,直至叶面布满水珠而不滴水为止。试验采用单因素完全随机区组设计,单株为1个小区,每个处理设5个重复。测定分析3种植物生长延缓剂处理下板栗苗木营养枝、标准枝的生长动态及叶片内非结构性碳水化合物的含量。【结果】①多效唑、矮壮素和烯效唑均能显著降低板栗苗木枝条长度,增加枝条直径,对于标准枝喷施30 mg/L烯效唑效果最好,处理后90 d使得标准枝长度较对照减少24.13%,直径增加26.45%;②延缓剂促进苗木枝条粗壮、长度缩短,延缓板栗砧木生长,提高嫁接成活率并有利于嫁接后生长,100 mg/L多效唑对营养枝促壮效果最好,较对照增加36.63%,长度减少17.10%。③延缓剂处理后,板栗叶片可溶性糖含量升高,其中150 mg/L矮壮素处理板栗苗木叶片内可溶性糖含量始终处于最高水平,且显著高于对照,在处理后90 d达到最高(61.95 mg/g)。④不同延缓剂处理对叶片淀粉含量有不同的影响,处理后30 d,100 mg/L矮壮素处理叶片内淀粉含量始终处于最高水平,且显著高于对照,在处理后60 d和90 d,淀粉含量分别高达1.54、1.51 mg/g;⑤3种延缓剂均能提高板栗苗木内非结构性碳水化合物含量,200 mg/L矮壮素处理对苗木非结构性碳水化合物增加效果最好,该浓度处理后的板栗苗木,其叶片内非结构性碳水化合物总量始终处于最高水平,最高达62.60 mg/g,且显著高于对照。【结论】植物生长延缓剂使得板栗苗木枝条粗壮、长度缩短,抑制砧木生长,从而提高板栗嫁接成活率并有利于嫁接后生长,其中60 mg/L烯效唑对标准枝的处理效果最好,100 mg/L多效唑对营养枝促壮效果最好;对板栗苗木喷施延缓剂有利于其叶片的碳供应,200 mg/L矮壮素处理效果最好;在植物生长延缓剂实际应用于板栗苗木培育中,应根据生产目的合理选择不同种类延缓剂及适宜的质量浓度。  相似文献   
979.
[目的]探索非结构性碳水化合物(non-structural carbohydrates,NSC)在落叶树种栓皮栎(Quercus variabilis)不同器官间的分配格局与调配机制,为进一步掌握树木生长规律并评估栓皮栎群落的固碳潜力提供参考.[方法]2016年5月-2017年6月,以秦岭东段栓皮栎为研究对象,通过旬...  相似文献   
980.
毛竹向撂荒地扩展过程中叶功能性状变化   总被引:2,自引:0,他引:2  
【目的】探索毛竹林扩展过程中叶片的适应特性和生存对策,为合理调控毛竹林的扩展提供依据。【方法】以毛竹-撂荒地扩展界面为对象,比较了不同扩展阶段毛竹比叶面积(SLA)、叶干物质含量(LDMC)及叶片主要养分元素及计量比等叶功能性状。【结果】①随着毛竹的扩展,SLA呈先上升后降低的趋势,扩展前期、中期和后期的SLA值分别为1.80、2.16和1.83 m2/kg。②不同年龄毛竹不同时期的LDMC的变化趋势不同,Ⅰ度竹LDMC随着毛竹扩展呈降低的趋势; Ⅱ和Ⅲ度竹LDMC呈升高的趋势。③随着毛竹的扩展,叶碳含量(LC)、叶氮含量(LN)、碳氮比(C/N)的变化差异不明显,叶磷含量(LP)呈降低的趋势,分别为1.70、1.53和1.15 g/kg; 碳磷比(C/P)呈升高的趋势,分别为264.06、292.33、392.03; 氮磷比(N/P)呈升高的趋势,分别为12.70、13.62和17.16。【结论】随着毛竹向撂荒地扩展,SLA 先升后降,Ⅰ度竹LDMC降低,Ⅱ和Ⅲ度竹LDMC升高,LP降低,C/P和N/P升高,毛竹主要叶功能性状随着环境的变化发生了适应性改变。毛竹通过降低SLA和N/P,增加LP含量来适应扩展前期剧烈变化的环境条件。随着毛竹的扩展和林分环境的形成,毛竹叶N/P增加,生长由受N制约变化为受P元素制约。Ⅰ、Ⅱ、Ⅲ度毛竹LDMC随着毛竹扩展的变化规律不同,使毛竹能够在扩展过程中更好地保有资源,具有 “集团”优势,能更灵活地利用资源。  相似文献   
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