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Chemicals are used widely as insecticides causing adverse effects to human health and the environment. Natural insecticides derived from plants which is eco-friendly. This study is to assess the efficacy of Ipomoea cairica extract against two different mosquito larvae. Lethal Concentrations (LC 50 ) of petal, leaves and root extract against Ae. albopictus larvae were 20.5, 27.9 and 34.3 mg/L respectively. Lethal concentration (LC 50 ) were found to be lower in Ae. aegypti which were 12.7, 13.6 and 31.9 mg/L respectively. In conclusion, these extracts can be utilized as an option in vector control program.

This study aimed to identify the Acanthamoeba genotypes and their pathogenic potential in five recreational hot springs in Peninsular Malaysia. Fifty water samples were collected between April and September 2018. Physical parameters of water quality were measured in situ while chemical and microbiological analyses were performed in the laboratory. All samples were filtered through the nitrocellulose membrane and tested for Acanthamoeba using both cultivation and polymerase chain reaction (PCR) by targeting the 18S ribosomal RNA gene. The pathogenic potential of all positive isolates was identified using thermo- and osmotolerance tests. Thirty-eight (76.0%) samples were positive for Acanthamoeba. Water temperature (P = 0.035), chemical oxygen demand (P = 0.026), sulphate (P = 0.002) and Escherichia coli (P < 0.001) were found to be significantly correlated with the presence of Acanthamoeba. Phylogenetic analysis revealed that 24 samples belonged to genotype T4, nine (T15), two (T3) and one from each genotype T5, T11 and T17. Thermo- and osmotolerance tests showed that 6 (15.79%) of the Acanthamoeba strains were highly pathogenic. The existence of Acanthamoeba in recreational hot springs should be considered as a health threat among the public especially for high-risk people. Periodic surveillance of hot spring waters and posting warning signs by health authorities is recommended to prevent disease related to pathogenic Acanthamoeba.

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This study intends to deal with the environmental consequences of the COVID-19 pandemic in Malaysia, by providing a summary of the effects of COVID-19 on municipal solid waste (MSW). In this analysis, the data on domestic waste collection were collected from the Solid Waste Management and Public Cleaning Corporation (SWCorp) from 1 January 2020 to 31 December 2020 to evaluate the relative changes in MSW percentage via a waste weighing method. The data consisted of the cumulative tonnage of MSW for every local authority in Peninsular Malaysia and was classified according to MCO phases; before the MCO, during the MCO, during the conditional MCO (CMCO) and during the recovery MCO (RMCO) phases. The results indicated that the enforcement of the early MCO showed a positive effect by decreasing the volume of MSW. This decrease was noted across 41 local authorities, which accounts for 87.23% of Peninsular Malaysia. However, the amount of MSW began to increase again when the MCO reached the conditional and recovery stages. From this, it can be concluded that the implementation of the MCO, in its various incarnations, has shown us that our lifestyles can have a harmful impact on our environment. While the pandemic was still spreading and limitations were still in place in Malaysia, local governments and waste management companies had to quickly alter their waste management systems and procedures. The current circumstance allows us to rethink our social and economic structures while improving environmental and social inclusion.

Increased resistance of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter sp. (ESKAPE) pathogens against various drugs has enhanced the urge for the development of alternate therapeutics. Quorum sensing (QS) is a density dependent cell-to-cell communication mechanism responsible for controlling pathogenicity with the regulation of gene expression. Thus, QS is considered a potential target for the development of newer anti-biofilm agents that do not depend on the utilization of antibiotics. Compounds with anti-QS effects are known as QS inhibitors (QSIs), and they can inhibit the QS mechanism that forms the major form in the development of bacterial pathogenesis. A diverse array of natural compounds provides a plethora of anti-QS effects. Over recent years, these natural compounds have gained importance as new strategies for combating the ESKAPE pathogens and inhibiting the genes involved in QS. Different pharmacognostical and pharmacological studies have been carried out so far for identification of novel drugs or for the discovery of their unique structures that may help in developing more effective anti-biofilm therapies. The main objective of this review is to discuss the various natural compounds, so far identified and their employed mechanisms in hindering the genes responsible for QS leading to bacterial pathogenesis.

The treatment of stabilized landfill leachate (SLL) by conventional biological treatment is often inefficient due to the presence of bio-recalcitrant substances. In this study, the feasibility of coagulation-flocculation coupled with the Fenton reaction in the treatment of SLL was evaluated. The efficiency of the selected treatment methods was evaluated through total organic carbon (TOC) removal from SLL. With ferric chloride as the coagulant, coagulation-flocculation was found to achieve the highest TOC removal of 71% at pH 6. Then, the pretreated SLL was subjected to the Fenton reaction. Nearly 50% of TOC removal was achieved when the reaction was carried out at pH 3, HO:Fe ratio of 20:1, HO dosage of 240 mM and 1 h of reaction time. By coupling the coagulation-flocculation with the Fenton reaction, the removal of TOC, COD (chemical oxygen demand) and turbidity of SLL were 85%, 84% and 100%, respectively. The ecotoxicity study performed using zebrafish revealed that 96 h LC for raw SLL was 1.40% (v/v). After coagulation-flocculation, the LC of the pretreated SLL was increased to 25.44%. However, after the Fenton reaction, the LC of the treated SLL was found to decrease to 10.96% due to the presence of HO residue. In this study, HO residue was removed using powdered activated charcoal. This method increased the LC of treated effluent to 34.48% and the removal of TOC and COD was further increased to 90%. This finding demonstrated that the combination of the selected treatment methods can be an efficient treatment method for SLL.