桂皮紫萁初生叶形态发育的观察

用腐叶土培养桂皮紫萁(Osmunda cinnamomea vat.asiatica Femald)的孢子,获得有性生殖苗.观察桂皮紫萁幼孢子体最初25枚叶片形态发生的详细过程,据此讨论了叶形态与环境适应性的关系、根茎叶之间的系统演化关系以及相关的系统学意义.     

油棕叶片干燥特性初探

为制备油棕叶片重组木,对油棕叶片干燥特性进行了分析。以油棕叶片为研究对象,采用电热鼓风干燥法进行试验,研究处理方式(未去皮、去皮、去皮碾压)、初含水率和干燥温度对油棕叶片干燥特性的影响。结果表明:处理方式、干燥温度对油棕干燥时间的影响均达极显著水平,初含水率影响达显著水平,其中去皮碾压处理和提高干燥温度更有利于缩短油棕叶片的干燥时间。油棕叶片最优的干燥工艺为去皮碾压、初含水率为50%、干燥温度为130℃,在该条件下的干燥时间为1.42 h。      

针对浮萍暴发式生长的植物源除草剂的筛选

浮萍暴发式生长给河道、湖泊、池塘等水体生态环境造成了较大困扰。探讨中草药提取液对浮萍植物的生长影响,以期为新型植物源除草剂的研制提供科学依据。通过对浮萍表观生长状态观察及对叶绿素、生物量等生长指标的检测,研究了7种常见中草药(甘草、地锦草、金钱草、泽漆、泽泻、黄连、鱼腥草)提取液对紫背浮萍(Soirodela polyrhiza)生长的影响。结果表明:黄连提取液对浮萍叶状体分蘖的抑制作用最佳,培养期间浮萍叶状体数几乎未增加;地锦草提取液对浮萍生物量增长的抑制能力最佳,培养96 h后浮萍生物量下降至对照组的69%;泽泻提取液对浮萍色素水平的影响最大,培养96 h后实验组叶绿素含量下降55%以上,杀青效果明显。因此,从中草药宝库中寻找抑制浮萍暴发的植物源除草剂是可行的。     

Compositional and structural characteristics of residual biomass from tropical plantations

Many products and abundant wastes from tropical plantations, such as latex, palm oil, and coconut production due to replantation, are waiting effective utilization. Nonutilized tropical biomass — oil palm (Elaeis guneensis Jacq.), coconut (Cocos nucifera L.) coir dust and coir fiber, and rubber (Hevea brasiliensis) wood — were analyzed for chemical and structural characteristics of wall polysaccharides and lignin. Coconut coir dust is mostly composed of middle lamella and is separated from coir fiber, which is composed of secondary walls. These were supported by lignin content, and structural characteristics of wall polysaccharides and lignin. The chemical and spectroscopic characteristics of walls of rubber xylem were similar to those of typical temperate angiosperm woods. Oil palm frond was significantly rich in arabinoxylan, and numerous acetyl groups were substituted to the arabinoxylan. Lignin of oil palm frond and wall polysaccharides of coconut coir dust are substituted with hydroxybenzoic acids with ester and ether linkages. Some p-hydroxybenzoic acid substituted to the wall polymers of coconut coir dust would contribute to the formation of associations between polysaccharides and lignin. Based on the above results it is suggested that coconut coir fiber and rubber wood are suitable resources for chemical pulp production for paper-making, but oil palm frond is not.     

Impact of different inclusion levels of oil palm (Elaeis guineensis Jacq.) fronds on fatty acid profiles of goat muscles

The effects of different inclusion levels of oil palm fronds (OPF) on the fatty acid profile of the longissimus dorsi (LD), biceps femoris (BF) and infraspinatus (IS) muscle of goats fed for 100 days are described. Twenty‐four individually housed Kacang crossbred male goats (averaged 21.7 ± 0.97 kg BW) were allocated to three groups receiving either a 100% concentrate control diet (CON), diet with 25% inclusion level of OPF (HAF) or a diet with 50% inclusion of OPF. The diets were adjusted to be isocaloric and isonitrogenous and fed at 3.0% of BW daily. Samples of LD, BF and IS muscles were taken at slaughter for the determination of fatty acid profiles. The total saturated fatty acids (SFA) in the LD and BF muscles of the OPF group were significantly (p < 0.05) lower than the CON group. For all muscles, C18:3n‐3 and total n‐3 polyunsaturated fatty acid (PUFA) were significantly higher (p < 0.05) in the OPF group than the CON group with minimal impact on the C18:2n‐6 and total n‐6PUFA. Consequently, the n‐6:n‐3 ratio significantly (p < 0.05) decreased in the OPF group compared to the CON group. The LD muscle had a significantly higher conjugated linoleic acid 18:2 c19t11 compared to other muscles. There were no interactions between muscle x diet except for total SFA. It is concluded that OPF at 25–50% inclusion levels may decrease the SFA and increase the n‐3PUFA content in chevon, with no apparent adverse effects on the growth performance of the animals, can be used as a feed ingredient to support goat farming in countries that lack grazing pasture.     

Development of boards made from oil palm frond II: properties of binderless boards from steam-exploded fibers of oil palm frond

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