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1.
Dissolving pulps are the raw materials for the production of many different end-products. Jute is a very good source of cellulose. In this investigation, jute fiber was subjected to pulping in soda process in order to produce dissolving pulp under different prehydrolysis conditions and compared with prehydrolysed kraft pulp from jute. An increase of the prehydrolysis temperature or H2SO4 in prehydrolysis liquor increased the α-cellulose content and decreased the viscosity of pulp. The effect of ethylenediamine in soda liquor was also investigated when producing dissolving pulp. Jute fiber produced pulp having 90–97% α-cellulose. Ethylenediamine in soda liquor produced pulp of higher yield, viscosity and higher α-cellulose content than that of prehydrolysis soda or kraft pulp. The α-cellulose content and viscosity were increased with the increase of amine in soda liquor. The kappa number of dissolving pulp from jute was very low (9–5), which indicated that less bleaching chemicals are required for bleaching. The bleachability of soda-ethylenediamine pulp was lower than prehydrolysed soda and kraft pulp in ECF bleaching sequences. The bleachability of soda-ethylenediamine pulp was improved at the sacrifice of pulp yield when prehydrolysis was done prior to pulping. The alkali solubility S 10 and S 18 were 4–9 and 2–4%, respectively.  相似文献   

2.
Marasmius palmivorus is a marasmioid fungal species that exhibits parasitic behaviour, although most marasmioids are rarely parasitic. The fungus has been reported to cause fruit bunch rot disease of oil palm and coconut, but only a few studies on its pathogenic behaviour are available, particularly on oil palm. Hence, there is a need to assess the ability of the fungus to act as a pathogen and to study its molecular evolution and taxonomy. Nine isolates of M. palmivorus were successfully isolated from basidiocarps and diseased fruitlets of oil palm collected from oil palm plantations and were morphologically characterized on potato dextrose agar (PDA) followed by molecular identification based on nucleotide sequence alignments of internal transcribed spacer (ITS) regions of ribosomal RNA (rRNA) gene clusters with sequences from GenBank. Koch's Postulates confirmed that M. palmivorus could infect oil palm fruitlets with symptoms similar to those observed for bunch rot disease. Molecular phylogenetic studies using nucleotide sequences of ITS and the nuclear ribosomal large subunit (nLSU) showed that isolates sharing the same phenotypic characteristics of Marasmius palmivorus and Marasmiellus palmivorus are monophyletic and share a common ancestor. The fungus has also been shown to be more closely related to the genus Marasmius than Marasmiellus; therefore, we support retention of the taxon name of the pathogen causing bunch rot disease of oil palm as Marasmius palmivorus.  相似文献   

3.
The methanol extract of the fruit pulp of Bromelia pinguin was evaluated for its antifungal activity. The extract showed a significant activity against some Trichophyton strains, although Candida strains were generally insensitive.  相似文献   

4.
The methanol extract of the fruit pulp of Psidium sartorianum was evaluated against seven Candida spp. and nine other fungal strains that are human pathogens. The extract showed a significant activity against seven Trichophyton species. Candida species were insensitive.  相似文献   

5.
Binderless boards were prepared from steam-exploded fiber of oil palm(Elaeis guineensis Jacq.) frond at six levels of explosion conditions. Their properties were investigated and evaluated. The mechanical properties (i.e., modulus of rupture, modulus of elasticity, and internal bonding strength) of the boards increased linearly with increasing board density as the usual hardboard. The boards made from fibers treated under a steam explosion condition of 25 kgf/cm2 (steam pressure) and 5 min (digestion period) exhibited the maximum strength. These boards at a density of 1.2 g/cm3 met the requirement of S-20 grade of JIS A 5905 — 1994 (fiberboard). Thickness swelling of the boards ranged from 6% to 14% under the JIS A 5908 — 1994 (particleboard) test condition and showed no significant changes with increasing board density. The main bonding strength of the board is believed to be due to a ligninfurfural linkage. Considering the chemical components of oil palm frond, which is rich in hemicellulose, there seems to be a good possibility for producing binderless boards using steam-exploded fibers of oil palm frond.This study was presented in part at the 2nd International Wood Science Seminar, Serpong, Indonesia, November 1998  相似文献   

6.
We evaluated the antifungal and antitermite activities of wood vinegars produced from oil palm trunk. The wood vinegars were produced at three different pyrolysis temperatures, 350, 400, and 450 °C. Antifungal activities of vinegars were evaluated using a Petri dish bioassay with 0.5, 1.0, and 1.5% (v/v) against a white-rot fungus, Trametes versicolor, and a brown-rot fungus, Fomitopsis palustris. Antitermite activities were tested using a no-choice bioassay method for Coptotermes formosanus with 2.5, 5.0, 7.5, and 10.0% (v/v). All the wood vinegars exhibited antifungal activities against T. versicolor. In particular, the wood vinegar produced at 350 °C resulted in complete inhibition of T. versicolor growth at 1.0 and 1.5%. However, higher concentrations were required to obtain growth inhibition of F. palustris. All the wood vinegars exhibited antitermite activity to C. formosanus workers in the no-choice experiment at relatively high concentrations. For instance, 10% concentration was required to achieve 100% mortality against C. formosanus at all production temperatures. The lowest mass loss of the treated filter paper of 11.75% was obtained with a 350 °C—10.0% combination.  相似文献   

7.
Oil production from oil palm is adversely affected by drought and salt. Under drought and salt stress, proline content increases in oil palm; the mechanism for this is unknown. Here, an 8319-nucleotide sequence including cDNA, genomic DNA and the promoter region of proline transporter gene from oil palm Elaeis guineensis was determined. The transporter gene exhibited high similarity to Bet/ProT genes from several plants, but the highest homology was found with rice ProT1. The exon-intron structure of genomic DNA was unique, and numerous stress-response cis-elements were found in the promoter region. Expression of cDNA EgProT1 in Escherichia coli mutant exhibited uptake activities for glycinebetaine and choline as well as proline. Under salt-stressed conditions, exogenously applied glycinebetaine was taken up into the root more rapidly than the control. These data indicate that oil palm has a unique Pro/T1 gene. Nucleotide sequence data for the cDNA and genomic DNA of proline transporter gene from Elaeis guineensis are available in the DDJB database under accession numbers AB597035 and AB597036, respectively.  相似文献   

8.
Litsea cubeba (Lauraceae) is woody plant endemic to Taiwan that is traditionally used as a spice. In the current study, several behavioral analyses were performed to evaluate the neuropharmacological activity of the essential fruit oil of L. cubeba in ICR mice. Oral administration of 100, 300 and 500?mg/kg of L. cubeba fruit oil significantly prolonged pentobarbitone-induced mouse sleeping time by 20.0, 110.8, and 159.6?%, respectively. In addition, after administration of L. cubeba oil, mice significantly increased the time spent in the open arms and number of entries into the open arms of an elevated plus maze compared to saline-treated mice suggesting that L. cubeba oil has anxiolytic activity. A tail-flick test conducted after treatment of mice with 500?mg/kg L. cubeba fruit oil also suggested that this oil has potent analgetic activity. According to GC/MS analyses, the essential fruit oil of L. cubeba oil consists of 23 compounds. The main components are geranial (37.16?%), neral (28.29?%), and d-limonene (22.90?%). We conclude that L. cubeba oil has a potent effect on the central nervous system of mice.  相似文献   

9.
Bud rot disease or “Pudricion del cogollo” (PC) of oil palm is a major constraint on production in Colombia and neighbouring countries such as Brazil, Costa Rica, Ecuador, Nicaragua, Panama, Peru and Surinam. To date, there are no documented reports of Phytophthora disease of oil palm in South‐East Asia. This research, therefore, was conducted to determine the pathogenic potential of Phytophthora palmivora and Phytophthora nicotianae on oil palm using both in vitro and nursery inoculation experiments. In vitro inoculation of both Ppalmivora and P. nicotianae on immature oil palm leaflets caused discoloration within 2 days of inoculation and incubation at 25 ± 1.5°C, 100% RH. Similarly, in nursery trials, lesions formed on the buds (unopened leaflets) 3 days after inoculation with Ppalmivora or P. nicotianae zoospore suspensions. No lesions developed on untreated leaflets in either in vitro or nursery inoculation experiments. Phytophthora spp. were re‐isolated from leaflet lesions and confirmed as the inoculated pathogens.  相似文献   

10.
11.
It has been reported that icariin and icariside II, two flavonoid glycosides coming from herba epimedii, which have a closely structural relationship, show some pharmacological effects such as preventing osteoporosis, cancer and depression. The content of natural icariside II is very low in herba epimedii, but it is the main component in vivo after the administration of herba epimedii. More icariside II can be obtained from icariin by enzymatic hydrolysis method than by traditional isolation method. This study focuses on finding a simple and feasible method to prepare icariside II from icariin by enzymatic hydrolysis, so as to meet the request for further pharmacologic actions study. Icariin was obtained successively with 90% ethanol extraction, isolation on macroporous resin and purification on silica gel chromatography. Enzymatic hydrolysis conditions were tested for the bioconversion of icariin into icariside II by orthogonal array design. The structures of isolated icariin and produced icariside II were identified by UV, IR, ESIMS, 1H NMR, 13C NMR, and DEPT spectroscope. Enzymatic hydrolysis experiment showed that icariin could be transformed into icariside II with the action of β-glucosidase and the optimum reaction conditions were determined as follows: 50 °C, 0.2 M disodium hydrogen phosphate and citric acid buffer system (pH6.0), the ratio of icariin/enzyme is 1:1 and reaction time 5 h. By using this enzymatic condition, 95.5 mg icariside II (with the purity of 99.1%) was obtained eventually by transforming 200 mg icariin.  相似文献   

12.
酶制剂对沙棘果汁出油率的试验研究   总被引:1,自引:0,他引:1  
李长春  张久红  邢洁 《沙棘》2006,19(1):17-19
通过试验研究介绍了一种新型的沙棘果汁出油技术:酶制剂在沙棘果汁出油率中的作用效果及其加工工艺。该工艺采用加入一定量的酶制剂(含果胶酶),它是在沙棘果经过压榨后对果汁组织细胞壁以及蛋白质大分子链进行有控制的破坏和降解,能在提高果汁出油率的同时,改善产品的色泽和品质。  相似文献   

13.
刘金江 《沙棘》2006,19(4):7-9
通过对浸制大果沙棘果实标本的最佳时期、桔黄色、桔红色沙棘果实的固定液及保存液的筛选试验,筛选出浸制大果沙棘果实标本的最佳时期和方法。  相似文献   

14.
In order to investigate the potential for efficient utilization of oil palm (Elaeis guineensis), supercritical water treatment (at 380°C and 100 MPa for 8 s) was applied to fractionate extractives-free samples into water-soluble portion and water-insoluble portion. The water-insoluble portion was further fractionated into methanol-soluble portion and methanol-insoluble residue. Samples were prepared from various parts of oil palm, i.e., trunks, fronds, mesocarp fibers, shells, empty fruit bunches, and kernel cake. These fractionated products were then characterized analytically. The water-soluble and methanol-soluble portions were determined to be mainly composed of carbohydrate-derived products and lignin-derived products, respectively. The methanol-insoluble residue was mainly composed of lignin (more than 84 wt%) and the phenolic hydroxyl contents determined by the aminolysis method was higher than for untreated oil palm samples. In addition, an alkaline nitrobenzene oxidation analysis indicated that the methanol-insoluble residue contained fewer oxidation products than untreated samples did. These findings imply that the water-soluble portion could be utilized for organic acid production, whereas the methanol-soluble portion and the insoluble residue could be used for the production of phenolic chemicals.  相似文献   

15.
Asekun OT  Adeniyi BA 《Fitoterapia》2004,75(3-4):368-370
The fruits essential oil of Xylopia aethiopica showed activity against four microorganisms and cytotoxicity to carcinoma cells (Hep-2 cell line) at 5 mg/ml concentration.  相似文献   

16.
The availability of undergrowth is essential for integrating ruminant animals into oil palm plantations. This is because undergrowth can be used as a feed resource for ruminants. This type of production system has the advantage of diversifying income and controlling weeds in the plantation. At least fve botanical groups of herbage can be found in oil palm plantations, namely, grasses, broad leaved plants, legumes, ferns and palms. Grasses were found in abundant through all palm ages. Most grasses are tolerant to higher light intensity and some are shade-tolerant. This study showed that in the early stages of oil palm crop development, sun-loving species tend to dominate the field, mostly broad leaves and legumes, but they will gradually be replaced by shade-tolerant plants when the canopies close. Concentration of metabolizable energy in herbage on offer was 4.6 to 7.0 MJ/kg dry matter. Crude protein content of grasses, broad leaves, legumes, ferns and palms are 11.5%, 15.4%, 16.3%, 12.5% and 12.0%, respectively. Ruminant animals preferred broad leaved plants more than other botanical groups found in oil palm plantation. This paper showed that metabolizable energy available (MEA) models can be used for predicting available energy (MJ/ha/day) from the system for grazing ruminants. This is because MEA model was developed based on both quality and quantity of herbage present in the ecosystem.  相似文献   

17.
The fertiliser industry faces a continuing challenge to improve the efficiency of their products, particularly of nitrogenous fertilisers, and to minimise adverse impacts. Therefore, a new slow release fertilizer, ureaimpregnated woodchips from tropical plant biomass(oil palm frond and rubberwood), was developed. The morphology of the impregnated woodchips was investigated by scanning electron microscopy and the success of impregnation of urea and nitrogen deposition into the woodchips was confirmed by energy dispersive X-ray spectrometry.When nitrogen release patterns from impregnated woodchips fertiliser were simulated using a soil solution and distilled water as leaching solutions in a static condition for 768 h, release was slow and steady, although the release rate was lower in distilled water than in the soil solution.  相似文献   

18.
王岳 《沙棘》2005,18(2):27-28
采用1L超临界萃取实验装置,对超临界CO2流体萃取沙棘全果油进行实验研究,分别考察了萃取压力、温度以及萃取时间等条件对萃取率的影响。结果表明:流量为20L/h时,萃取压力为30Mpa,温度为40℃,萃取时间为3h条件下,萃取率可达18%以上。化学成分分析结果表明:沙棘全果油中富含胡萝卜素、甾醇等多种生物活性成分.  相似文献   

19.
沉香籽在南方资源量大,内含油脂丰富,其中C18组分高达80.4%,在我国能源短缺的大背景下具有重要的开发意义。本研究自制负载型固体碱催化剂KF/CaO用于催化沉香籽油进行酯交换反应制备脂肪酸甲酯类生物柴油。通过表征发现催化剂KF/CaO微观呈多层片状结构,比表面积为107±0.5 m2/g,碱强度H_=15.0~18.4。通过酯交换反应发现KF/Ca O催化剂具有较好的催化效果,酯交换转化率达到98.7%,能够保持高转化率重复使用3次。生物柴油产品主要指标符合GB/T 20828-2014的要求,红外谱图显示符合脂肪酸甲酯官能团的特征。  相似文献   

20.
Oil palm plantations have been touted as one of the main drivers of deforestation in Indonesia. This paper aims to explain how oil palm companies accumulate power that enables them to control forestland and convert it into oil palm. Specifically, this paper identifies empirical evidence pointing to why oil palm companies emerge as powerful actors in land use conflicts. This paper uses the case of forest lands claimed by different actors – i.e. a timber plantation company, an oil palm company, and local communities – in West Kalimantan, Indonesia. Before the decentralisation policy, the interests of timber plantations were principally safeguarded by coercion from the forest ministry. The timber company was also supported by local communities by promising financial incentives to them. Following the decentralisation policy, additional actors get involved in the land use conflicts leading to more complex power interplays. In fact, some forestlands licensed for timber plantations are used by the oil palm company. Oil palm interests resonate with the economic interests of local governments, who use their legal mandates on land use allocation to facilitate the establishment of oil palm. The power of the oil palm company is also enhanced by the support from local communities, to which it handed more financial incentives than those of the timber plantation. It also used dominant information of customary claims and land appropriation by the ministry of forestry, with which it persuades local communities to pressurize government institutions to support oil palm operations.  相似文献   

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