Influence of Solvent onto Chemical Extraction of America-Type Coconut (Coco nucifera L.) Fbers: Analysis of Physicochemical, Mechanical and Morphological Properties

In this study, the natural fibers from Coconuts of the species Coco nucifera L. were Chemically extracted in different solvents such as sodium hydroxide (SH), acetone (AC) and sodium hydroxide-acetone (SHA) for their applications in the textile industries. Structural, morphological and physico-mechanical characterizations such as X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR), scanned electron microscopy (SEM), measurements of density, Young’s modulus, water absorption rate and humidity were evaluated. The XRD and FTIR results show that Coco nucifera L. fibers contains type I cellulose. Mechanical characterizations were also carried out. These results show that by varying the different solvents used, the physico-chemical, mechanical and morphological properties of the fibers change, which implies that the solvent has an influence on the properties of these fibers. The fibers extracted by the sodium hydroxide-acetone mixture have a linear density of 1.636, the percentage of water absorption is 62.428%, the percentage of moisture absorption 9.605% compared to other values in the literature shows that this solvent mixture improves the properties of coconut fibers which contain type I cellulose. The tensile stress is 0.013 GPa, the percentage strain is 49.836% and the Young’s modulus is 0.114 GPa as well as the percentage elongation show that these fibers are elasto-plastic. The values obtained mean that these fibers are suitable for use in textiles.

Construction and Characterization of a cDNA Library from the Pulp of Coconut (Cocos nucifera L.)

To investigate the gene expression profile of endosperm development, a cDNA library was constructed and characterized from the pulp of coconut at different developmental stages. The constructed cDNA library incorporated approximately 1 × 10^7 clones in total, and the size of the insertion fragments ranged from 800 to 2 000 bp. Sequencing results of 100 randomly picked clones showed that the recombination rate was 96%. In subsequent sequence analysis, 41 clones （41%） were homologous to known function proteins, and 23 clones showed high amino acid identity （more than 80%） with the corresponding genes of different plants. Semi-quantitative RT-PCR indicated that oleosin and globulin genes are pulpspecific expression, and have differential expression level in different developmental stage. Clone 29, recognized as homologous to KIAA1239 protein （Homo sapiens）, was observed to occur nine times, indicating that this gene may be over-expressed during the endosperm development stage. However, the homologous protein was found only in mammals, and the detailed function is still unknown. Elucidation of the functional characterization of these genes will be carried out immediately.

Cocos nucifera L.water as green corrosion inhibitor for acid corrosion of aluminium in HCl solution

The ability of Cocos nucifera L.water（CW） as non-toxic corrosion inhibitor for acid corrosion of aluminium in 0.5 mol/L HCl has been studied using chemical technique.CW shows significant inhibition as corrosion inhibitor,with 93%efficiency at the highest concentration of the inhibitor.The inhibitive action is attributed to the adsorption of the inhibitor molecules on metal surface following Langmuir adsorption isotherm.

Synergistic Mixture of Cyperus esculentus, Phoenix dactylifera and Cocos nucifera Aqueous Extract: Its Liver and Kidney Benefits in Male Albino Rat Model

Background: The synergistic mixture of Cyperus esculentus, Phoenix dactylifera and Cocos nucifera (STCD) aqueous extract is a common drink in Port Harcourt, Nigeria. It is assumed to have various health benefits. However, the synergistic mixture of the content has not been studied scientifically, hence the need to evaluate its effect on the liver and kidney being part of the body’s metabolic organs. Aim: This study evaluated the synergistic mixture of Cyperus esculentus, Phoenix dactylifera and Cocos nucifera (STCD) aqueous extract in male albino rats. Methods: Acute toxicity LD50 of STCD was carried out, afterwards, fifteen male albino rats were grouped into three groups with 5 rats in each group;Control, 200 mg/kg, 400 mg/kg STCD. The rats were administered STCD orally 24 hourly, for 21 days, with feed and water ad libitum. At the end of the experiment, blood samples were collected for biochemical analysis of the liver and kidney biomarkers, while the liver and kidney tissues were harvested for histopathological examination using standard laboratory methods. Descriptive statistics were computed and expressed as Mean ± SD. One-way ANOVA and Turkeys test was performed. P value ≤0.05 was considered statistically significant. Results: Acute toxicity LD50 of STCD was observed to be ≥2404.2 mg/kg body weight. An increase in the percentage body weight difference of 8.39% and 2.86% was observed for 200 and 400 mg/kg STCD groups. Also, the liver weight was observed to increase in 400 mg/kg (3.92 ± 1.42) in comparison to the control group (3.48 ± 1.61), a decrease in the kidney weight was observed in all groups administered STCD in comparison to the control group. Administration of STCD at both 200 and 400 mg/kg revealed a decrease in the concentration of the hepatic biomarkers AST, ALT, ALP, TP, Albumin, Total and conjugated bilirubin. The kidney biomarker Urea was observed to decrease in concentration for 200 mg/kg STCD (4.60 ± 1.83) and 400 mg/kg STCD (4.76 ± 0.74) when compared to the control group (6.32 ± 2.74). A decrease in Creatinine was observed in 200 mg/kg (91.80 ± 34.69) and 400 mg/kg (98.60 ± 15.53) in comparison to the control group (117.60 ± 42.88). The histological examination of the liver of rats administered STCD revealed structural normal central vein, hepatocytes and portal tract. The kidney examination revealed normal glomeruli and normal tubule. Conclusion: The findings of this study opine that STCD improved the health of both the liver and kidney as evidenced via the biomarkers and histological examinations of the liver and kidney. This study therefore recommends the intake of STCD at moderate doses for improved liver and kidney function due to its bioactive compounds and nutritional content.

Evaluation of the Antimicrobial Activity of Endophytic Fungus Isolated from <i>Cocos nucifera</i>(L.) Cotyledon against Medically-Important Pathogens

The study aimed to evaluate the endophytic fungi isolated from Cocos nucifera (L.) cotyledon for their possible antimicrobial activity. A total of twelve endophytic fungal species were successfully isolated, from which five were selected and presumptively identified, including Aspergillus niger, Raffaelea sp., Aspergillus flavus, Cladosporium sp. and Pseudallescheria spp. based on their macro and microscopic characters. The agar blocks of actively growing pure culture were assessed for antibacterial activity against five human pathogenic bacterial and fungal strains: Escherichia coli (BIOTECH 1634), Bacillus subtilis (BIOTECH 1697), Staphylococcus aureus (BIOTECH 1592), Serratia marcescens (BIOTECH 1748), and Candida tropicalis (BIOTECH 2085). Among the selected five endophytic used for antimicrobial activity screening, the Raffaelea sp. (CN-EF 2) has shown a high zone of inhibition of 11 mm against Bacillus subtilis, 18 mm against Escherichia coli, 15 mm against Staphylococcus aureus, and 11 mm against Candida tropicalis. Correspondingly, Aspergillus niger (CN-EF 1) has shown a zone of inhibition of 16 mm against C. tropicalis. The endophytic fungus Raffaelea sp. was effective against all test organisms except for Serratia marcescens, while Aspergillus niger was only effective for pathogenic fungi C. albicans. Hence, further in-depth studies of the isolated endophytic fungi are needed to determine the mechanisms behind the endophytes’ inhibitory effects.

Genetic Diversity and Structure of East African Tall Coconuts in Tanzania Using RAPD Markers

RAPD markers were used to estimate levels of genetic diversity and structure among twelve East African Tall (EAT) coconut (Cocos nucifera L.) accessions that are maintained at Chambezi station. Ten primers were used in the analysis of 120 accessions. Cluster analysis was performed based on Jaccard’s coefficient and Nei genetic distances. Further analyses included principal coordinate analysis (PCA) and finally bootstrap analysis. The cluster analysis revealed two main clusters. One cluster contained provenances from Lindi and Mtwara regions (south) and those from Coast and Dar es Salaam regions (central);the second had provenances from Tanga region, which is the northern part of the coastal belt. A similar distribution of provenances was shown by the results of the principal coordinate analysis, whose first three coordinates explained 56% of the total variation. The results were able to discriminate between the different provenances and provide evidence of the different origins for the coconut palms in the northern and southern parts of coastal coconut-growing belt. The two major clusters concur well with the history and distribution of coconuts in the coastal belt of Tanzania.

Long-term consumption of virgin coconut (Cocos nucifera) oil diet impairs learning and memory in CD1 mice

Objective:Virgin coconut oil(VCO)has been used in the management of dementia in Alzheimer’s disease(AD).Therefore,this research investigated the effect of long-term consumption of VCO diet on learning and memory in CD1 mice.Methods:Thirty male CD1 mice(divided into three groups,n=10)were fed with standard rodent chow(control),5%and 20%VCO diets(respectively)for 28 d.The Morris Water Maze(MWM)test was used to test the effect of VCO on visuo-spatial learning and memory,while the Novel Object Recognition Test(NORT)was used to measure short-and long-term recognition memory.Results:Learning performance of mice did not differ in the MWM.During the probe trial,duration in the retention quadrant and annulus crossings were lower(P<0.05)in the 5%and 20%VCO diet groups compared to the control diet group,showing that VCO impaired visuo-spatial memory.During the NORT,mice showed more total approaches in the 20%VCO diet group(P<0.05)compared to control and the 5%VCO diet groups during the short-term memory test.During the long-term memory retention test,the total approaches were also higher in the 20%VCO group compared to control and 5%VCO group(P>0.05).The discrimination index was also lower in the 20%VCO group compared to control and 5%VCO diet groups indicating impaired long-term cognitive memory in mice given 20%VCO diet.Histological examination of brains showed damage within the CA1 pyramidal cell layer of the hippocampus in the 20%VCO diet group,in line with the behavioural observations.Conclusion:Long-term consumption of virgin coconut oil diet impairs memory in mice.

基于Open Modeller-GARP的椰子在中国的适生区预测

【目的】研究椰子在我国的适生区,为椰子的推广种植提供技术支持。【方法】通过实地调查和已公开发表的科技论文,获取椰子在我国的已知分布点,结合环境数据,使用Open Modeller-GARP模型预测椰子在我国的可能适生区域。【结果】椰子在中国的潜在适生区为:广东的湛江市、徐闻县、雷州市、遂溪县、廉江市、化州市、吴川市、高州市、茂名市、阳江市、阳春市、江门市(南部)、开平市、中山市、珠海市、深圳市、惠州市(南部)、汕尾市、汕头市;广西的北海市、防城港市、东兴市、靖西县、那坡县;云南的勐腊县、景洪市、普洱市、江城县、绿春县、金平县、屏边县、河口县;西藏的聂拉木县、普兰县;海南、香港、澳门及台湾全省。【结论】在我国除了海南、台湾、云南的西双版纳州、广东的雷州半岛、广西的北海外,尚有广西、广东、云南、西藏、香港、澳门等6省区的28个市(县)适合椰子栽培,可在这些地区进行适应性栽培后发展椰子生产。

鲜食加工兼用型椰子种质鉴定和综合评价

为了筛选鲜食加工兼用椰子种质,为椰子种质资源鉴定和兼用型新品种选育提供参考,对44份椰子种质8月龄及12月龄果的33个果实性状指标进行测定和变异分析、聚类分析,对其中18个性状进行相关性分析,对9个主要性状开展主成分分析,并对种质进行综合评价。变异分析结果表明,8月龄果性状的变异系数为9.97%~37.16%,12月龄果性状的变异系数为8.90%~41.28%;聚类分析表明,根据8月龄及12月龄果性状均可将44份种质分成三大类,分别为椰水糖度高、中、低3类及椰肉占比高、中、低3类;相关性分析结果表明,18个性状之间存在不同程度的相关性,其中12月龄果椰肉占比与椰果质量、椰果长、椰果宽存在显著负相关,但是8月龄、12月龄果的椰水糖度与其他性状间均无显著相关性;主成分分析表明,9个性状可以简化为3个主成分,累积贡献率达到83.896%;通过综合评价筛选出10份鲜食加工综合性状优良的椰子种质。分析结果说明44份椰子种质在果实性状方面具有丰富的多样性,聚类分析为选择不同特点的种质提供了选择范围,果实性状之间存在大量的显著相关性,筛选出V405、Y224、Y261等10份综合表现较好的种质,为兼用型种质创制和新品种培育提供了基础材料。

海南椰子栽培品种的SSR标记分析

应用简单重复序列（SSR）标记方法，对海南的11个椰子（Cocos nucifera L．）栽培品种进行了遗传多样性分析。选取30对引物用于PCR扩增，有23对引物扩增出有效多态性片段136条，平均多态性百分率为95．77％，每对引物扩增出的带数2-12条不等，平均为6．17条，每个SSR位点的多态信息量（PIC）在0．173～0．896之间，平均为0．561。11份材料之间遗传相似系数变化范围0．061—0．861，说明海南椰子栽培品种之间存在丰富的遗传多样性。UPGMA聚类分析结果表明，11个椰子栽培品种分为4个类群和两个亚群。SSR标记反映出的品种问亲缘关系与形态学研究的分类结果并不完全吻合。

椰子ISSR遗传多样性分析

应用ISSR技术分析了来自多个国家的30份椰子品种或类型的遗传多样性。用29条多态性较好的引物共扩增出了157条条带,其中多态性条带110条,多态性比率70%;用NTSYS软件计算出这30份材料的DICE相似系数在0.548～0.962,平均值为0.788。其中相似系数最高的是红矮(14号)和杂交种(16号)为0.962,最低的是海南高种(29号)和斐济高种(5号)仅0.548。用UPGMA方法构建聚类树,所有材料在相似系数0.79处被划分为三大类(类群A,B,C)。A类群包括所有引进的高种、矮种和杂交种,B类群包含了除雄树以外的所有特殊变异类型椰子,而来自海南的所有高种单独聚为C类。综合研究结果表明我国海南的椰子种质资源多样性水平不高,需要进一步引进国外优良种质。

椰子的开发利用

介绍了热带资源椰子的结构与组成,概述了国内外椰肉、椰子水、椰衣、椰壳、椰木、椰花等开发利用产品的生产工艺及其用途,并展望了我国椰子的广阔开发利用前景,针对国内椰子开发利用的现状,提出了开发利用椰子的建议.

云南椰子种质资源遗传多样性的ISSR分析

为摸清云南椰子种质资源遗传多样性现状,促进资源的有效利用,以在云南收集的60份椰子种质为试材,利用ISSR分子标记技术对其遗传多样性进行了分析。结果表明:27条ISSR引物共扩增出272个位点,其中230个为多态性位点,多态性比率为84.56%,引物多态性指数为0.85,SM遗传相似系数平均值为0.664。根据各种质的SM,运用NTSYSpc2.10e软件的UPGMA方法构建了种质的系统聚类图,60份椰子被聚为3个类群(A、B、C)。其中,A类群为全部由本地种质组成的一个独立类群;C类群既包括部分本地种质,也包括来源于本地以外的其他种质。研究结果显示出云南椰子种质具有较高的遗传多样性;这些种质与外地种质具有独立性和关联性的特点。该研究结果可为云南椰子种质资源的进一步研究和利用提供参考。

海南椰子2种新类型

调查了海南省南部地区的椰子种质资源,发现了2种中果皮为粉红色的新椰子类型。根据外果皮和中果皮颜色,将它们分别暂命名为青皮红衣椰子和红皮红衣椰子。

椰子植物叶基因组DNA提取

采用改良CTAB法和SDS法提取椰子基因组DNA,并通过琼脂糖凝胶电泳、分光光度计进行紫外检测.结果表明使用改良的CTAB法较SDS法抽提椰子属植物中总DNA纯度和含量要高,适合分子生物学操作的要求,为后续椰子遗传多样性分析、遗传图谱构建等研究奠定基础.

外源水杨酸对低温胁迫椰子幼苗生理特性的影响

【目的】研究外源水杨酸(SA)对低温胁迫下不同品种椰子幼苗抗寒生理指标的影响,为提高椰子幼苗抗寒能力及选育抗寒椰子新品种提供参考依据。【方法】以1年生文椰78F1、文椰2号、文椰3号和文椰4号幼苗为研究材料,分别喷施100.0、150.0、200.0和250.0 mg/L外源SA,测定分析其4℃低温胁迫1~5 d叶片的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性及丙二醛(MDA)和脯氨酸(Pro)含量。【结果】4个外源SA处理的椰子幼苗在4℃低温胁迫5 d内,叶片的SOD、CAT和POD活性及Pro含量均高于相应的清水对照(CK),且总体上均呈先上升后下降的变化趋势;MDA含量均低于CK,且呈先下降后上升的变化趋势;4℃胁迫第2 d,喷施150.0 mg/L SA的文椰78F1、文椰2号、文椰3号和文椰4号幼苗叶片SOD、CAT和POD活性及Pro含量最高,均显著高于相应的CK和其他浓度处理(P<0.05,下同),MDA含量最低,均显著低于相应的CK和其他浓度处理,其中以文椰78F1幼苗的SOD、CAT和POD活性及Pro含量更高,MDA含量更低。同一低温胁迫时间不同浓度SA处理中,总体上也以150.0 mg/L SA处理各椰子品种幼苗的SOD、CAT和POD活性及Pro含量最高,MDA含量最低,在4个椰子品种中,以文椰78F1幼苗的SOD、CAT和POD活性及Pro含量更高,MDA含量更低,其次为200.0和250.0 mg/L SA处理,100.0 mg/L SA处理的5个抗寒指标变化不明显。【结论】喷施150.0 mg/L外源SA能提高椰子幼苗的抗寒性,尤其对文椰78F1幼苗的抗寒效果更佳,可在椰子抗寒育苗及抗寒椰子新品种选育中推广应用。

椰子平脐蠕孢叶斑病病原鉴定及生物学特性测定

2012年10月，在海南省文昌市的椰子苗圃中，发现了一种新的叶斑病。显微观察表明，病原菌分生孢子稍弯曲，浅褐色，纺锤状或梭状，具有5-9个假隔膜、分生孢子梗多单生，直立或稍弯曲，表明其为平脐蠕孢属（Bipolari．sp）。ITS序列分析表明其和4株狗尾草平脐蠕孢的序列同源性（HE792936．1，JX462256，GU073108．1，FJ606786．1）的同源性为99％。生物学特性研究结果表明：该菌菌丝适宜生长温度为20～30℃，菌丝生长和孢子最适萌发温度分别是25℃和30℃；最适pH值为4～11；玉米粉培养基（CAM）及马铃薯葡萄糖琼脂培养基（PDA）最适合菌丝生长．最佳碳源为蔗糖。甘油不适合菌丝生长；最佳氮源为蛋白胨，其次是磷酸氢二铵：完全光照有利于菌丝生长。菌丝及分生孢子的致死温度和时间分别是56℃，15min。

5个椰子品种植株叶片解剖结构的观察

采用石蜡切片技术,对5个椰子品种的成年植株叶片进行观察和比较。结果表明:各品种叶片的基本组成相同,但叶片各组成部分的厚度存在差异,其中栅栏组织厚度和叶片厚度的差异灵敏度较高,在总次数为10次的多重比较中,差异极显著次数分别为7次和6次。结合供试材料的田间抗寒性观察发现,抗寒性最强的海南本地高种具有最厚的栅栏组织和叶片,抗寒性最弱的文椰4号的栅栏组织和叶片厚度最小。因此,叶片的栅栏组织厚度和叶片厚度可能从一定程度上反映了椰子品种的抗寒性,可以作为抗寒指标。

椰子不同组织基因组DNA的提取及质量分析

以椰子植物的叶片和花序组织为材料,探索了应用CTAB微量法分离高质量椰子基因组DNA的方法.结果表明,采用CTAB的缓冲液裂解材料,以及在提取过程中用φ=4%的β-巯基乙醇的改良CTAB法,可有效地控制椰子这种高纤维、易褐变材料和多糖在DNA提取过程中的污染和影响.应用本研究建立的分离方法,可从椰子的叶片和花序2种不同材料中分离得到高质量的基因组DNA,产量分别达0.75 g.L-1和0.65 g.L-1.通过Hind III酶切实验证明,分离出的基因组DNA适用于限制性酶切反应的分析和操作;该方法的建立可有效地应用于椰子和其他棕榈科植物基于DNA的分子生物学研究.

椰子胚的离体培养研究

以椰子成熟胚为外植体,得出其胚培养和植株再生的最适培养条件如下:①胚的启动培养最适培养基为Y3+6-BA0.5mg·L-1+NAA0.5mg·L-1+蔗糖60g·L-1+活性炭2.5g·L-1的液体培养基;②继代培养最适培养基为Y3+6-BA1.0mg·L-1+NAA1.0mg·L-1+蔗糖60g·L-1+活性炭2.5g·L-1+琼脂7.0g·L-1;③最适生根培养基为Y3+IBA2.0mg·L-1+NAA2.0mg·L-1+6-BA1.0mg·L-1+蔗糖45.0g·L-1+活性炭2.5g·L-1+琼脂7.0g·L-1。试管苗经练苗移栽后,成活率达90%以上。