In this work, chemically treated microcrystalline cellulose (MCC-C) was extracted from coconut husk fiber. In order to extract hemicellulose, the sieved coconut husk fiber was treated with sodium hydroxide (NaOH) for dewaxing and acidified using sodium chlorite (NaClO2) to extract the residual lignin (bleaching process). The obtained lignin-free cellulose was then treated with potassium hydroxide (KOH). The characterizations used to equate the MCC-C with commercial grade microcrystalline cellulose (MCC) are solubility test, X-ray diffractogram (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The XRD showed that the crystallinity of MCC and MCC-C increased significantly by 80.15% and 71.8% by chemical treatments. TGA found that the active removal of lignin-hemicelluloses and the thermal stability of the material were about 350–500°C and 300–500°C. The morphology of the fiber confirmed that there is an irregular cross-section, non-uniform surface, a large amount of short microfibrils and some impurities on the surface of the coconut husk fiber. The findings showed that microcrystalline cellulose has been successfully extracted from coconut husk fiber and that it can be used further.
Riparian areas hold vast number of flora and fauna with exceptional contributions to the ecosystem. A study was conducted in Sungai Sepetang, Sungai Rembau and Sungai Chukai to identify the insect community in a riparian zone of Peninsular Malaysia. Sampling was conducted in six consecutive months from December 2017 to May 2018 during both day and night using sweep nets. Twenty sampling stations (S1-S20) had been assembled along the riverbanks with an average distance of 200 m between each station. The 17,530 collected insects were from 11 orders and consisted of Diptera, Coleoptera, Hemiptera, Hymenoptera, Lepidoptera, Neuroptera, Orthoptera, Blattodea, Thysanoptera, Mantodea and Odonata. The three most abundant orders were Diptera (33.84%; 5933 individuals), Coleoptera (28.82%; 5053 individuals) and Hemiptera (25.62%: 4491 individuals). The collected insect community consisted of different guilds such as the scavenger, predator, herbivore, pollinator and parasitoid. Sungai Sepetang and Sungai Rembau were dominated by mangrove flora,Sonneratia caseolaris(Myrtales: Lythraceae), while Sungai Chukai was dominated byBarringtonia racemosa. There was a significant difference (p < 0.05) in the composition of insects between the three rivers though clustering analysis showed that the insect communities in Sungai Sepetang and Sungai Rembau were 100% similar compared to Sungai Chukai which consisted of a totally different community. There is a significant negative correlation between abundance of insects with salinity and wind speed at Sungai Chukai and Sungai Sepetang.
7 September 2021 in Environmental Monitoring and Assessment
The synchronous-flashing firefly, Pteroptyx tener Olivier, 1907 is a congregating firefly with high economic value for the ecotourism industry. However, the populations of P. tener are increasingly being threatened due to habitat destruction. The assessment of genetic variation within and among populations of the species from Malaysia might play a major role in conservation and management programs. Objectives of this study were to investigate the relationships among P. tener from five populations in Malaysia (Peninsular Malaysia and Borneo (Sabah) using cytochrome oxidase subunit I (COI), and to obtain its haplotype information. A total of 50 sequences of P. tener were used in the Neighbour-Joining (NJ), Maximum Parsimony (MP), and Bayesian Inference (BI) phylogenetic analyses and successfully formed several distinct clades of West and East Malaysia (East Coast and West Coast of Peninsular Malaysia) with moderately to highly supported bootstrap values and posterior probabilities. Several haplotype analysis parameters are presented; low nucleotide diversity (PiT, 0.01893), haplotype number (Hn, 19), and high haplotype diversity (Hd, 0.89469). Our findings assumed that the geographical isolation due to the inability for flying long distances without help by the wind and flooding in tidal rivers. The data presented here are important genetic information on the P. tener populations and are important for the conservation programme in Malaysia by conducting the breeding program among populations that have similar genetic information.
This checklist serves as a basic information based on compilation from published literatures, internet database and from specimens’ collection stored at Center of Insect Systematics Universiti Kebangsaan Malaysia. To date, this study compiled smaller arachnids (28 species) and Pseudoscorpiones (41 species) that had been recorded in Malaysia. Although smaller arachnid orders were concentrated at localities with average rainfall and humidity, Pseudoscorpiones can be found at both wet and dry environments. More work is needed to determine the species diversity and distribution of these cryptic group.