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PurposeTraditional Malaysian vegetables, also known as ulam, are believed to have healing properties among the local community. Ulam is commonly reported to have high antioxidant content which makes it a popular food. The purpose of this paper is to determine the teratogenic potential of eight ulam, using zebrafish model. The tested ulam were Cosmos caudatus, Gynura procumbens, Labisia pumila var. alata, Phaleria macrocarpa, Polygonum minus, Piper sarmentosum, Premna foetida and Sauropus androgynous.Design/methodology/approachMethanol extract of ulam was prepared using the maceration method. Various concentrations of extracts were tested against fish embryo short-term toxicity test. The lethal concentration (LC50) and teratogenic effect of the ulam were determined.FindingsAmong all tested species, L. pumila, P. foetida and S. androgynous showed 100% lethal effect towards zebrafish embryos at concentrations of 10 µg/mL, 1,000 µg/mL and 100 µg/mL, respectively. The three ulam have exhibited teratogenic effect on zebrafish embryos after 72 h post-fertilization. L. pumila had induced yolk sac edema at 1.0 µg/mL for normalized measurement of 108.3 ± 2.0% (which is higher than negative control, p P. foetida had induced pericardial edema at 100 µg/mL for normalized measurement of 124.0 ± 4.6% (which is higher than negative control, p S. androgynus induced curve trunk at 30 µg/mL for the presence of 70.9 ± 4.2%.Originality/valueThe teratogenic effect of L. pumila, P. foetida and S. androgynous suggests the possible disruption in the embryogenesis in zebrafish, namely Notch, vascular endothelial growth factor (VEGF) and retinoic acid pathways. The results of ulam gave possible implications and insights on the cancer pathways involved, which could be a useful target for cancer research. This is the first report on teratogenicity evaluation of Malaysian ulam showing relationship to cancer pathways by using zebrafish embryo model.

Objective To investigate the larvicidal activity, inhibition effect on development, histopathological alteration and morphological aberration induced by the extracts derived from seaweeds Bryopsis pennata ( B. pennata ) , Sargassum binderi ( S. binderi ) and Padina australis in Aedes aegypti ( Ae. aegypti ) larvae and to characterize the phytochemical components of the three seaweeds. Methods Larvicidal activity of the seaweeds towards the larvae of Ae. aegypti was determined according to WHO. The inhibition effect of seaweeds was assessed by determining the mortality, adult emergence rate, larval and pupa duration of the treated larvae. Histopathological effect on midgut epithelium of larvae and morphological aberration induced by the methanol extracts were examined. Phytochemical analysis was done to determine the presence of alkaloids, saponins, steroids and terpenoids in the seaweeds. Results Chloroform partition of B. pennata extract exhibited the strongest larvicidal activity (LC 50 = 82.55 μg/mL), followed by methanol extract of B. pennata (LC 50 = 160.07 μg/mL) and chloroform partition of S. binderi extract (LC 50 = 192.43 μg/mL). The methanol extract of S. binderi exhibited the strongest effect on prolongation of larval period (1.5-fold longer as compared to control) and resulted in strongest inhibition effect in adult emergence (98.67%). The histopathological study showed that larvae treated with seaweed extracts had cytopathological alteration of the midgut epithelium. The morphological observation revealed that the anal papillae and terminal spiracles of larvae were the common sites of aberrations. Conclusions The study provided information on various effects of seaweed extracts on Ae. aegypti . Further investigation on identifying the active compounds and their mechanisms of action is recommended.

The ever-increasing threat from infectious diseases and the development of insecticide resistance in mosquito populations drive the global search for new natural insecticides. The aims of this study were to evaluate the mosquitocidal activity of the extracts of seaweed Bryopsis pennata against dengue vectors Aedes aegypti and Aedes albopictus, and determine the seaweed’s toxic effect on brine shrimp nauplii (as a non-target organism). In addition, the chemical compositions of the active larvicidal extract and fraction were analyzed by using liquid chromatography-mass spectrometry (LC-MS). Chloroform extract exhibited strong ovicidal activity (with LC50 values of 229.3 and 250.5 µg/mL) and larvicidal activity against Ae. aegypti and Ae. albopictus. The larvicidal potential of chloroform extract was further ascertained when its A7 fraction exhibited strong toxic effect against Ae. aegypti (LC50 = 4.7 µg/mL) and Ae. albopictus (LC50 = 5.3 µg/mL). LC-MS analysis of the chloroform extract gave a tentative identification of 13 compounds, Bis-(3-oxoundecyl) tetrasulfide was identified as the major compound in A7 fraction. Methanol extract showed strong repellent effect against female oviposition, along with weak adulticidal activity against mosquito and weak toxicity against brine shrimp nauplii. The mosquitocidal results of B. pennata suggest further investigation for the development of effective insecticide.

Despite the extensive work on anticancer drug discovery, the number of potent lead compounds that enter the preclinical and clinical trials thus far is still low due to the poor selectivity and understanding in pharmacodynamics. In view of the homology between zebrafish embryogenesis and carcinogenesis in human, zebrafish embryos can be used in the screening platform to elucidate the molecular targets of potential anticancer compounds. In the present study, the possible targets modulating the potential anticancer effects of selected brown seaweed-derived compounds (ie alginate, fucoidan, phloroglucinol, fucosterol, and fucoxanthin) were examined. Teratogenic effects induced by the compounds were observed after 72 hours post-fertilization. Fucoidan, phloroglucinol, and fucosterol were observed to significantly reduce the pigmentation of the zebrafish in a dose-dependent manner at low concentrations (fucoidan

Objective: To assess the insecticide susceptibility status of Anopheles cracens (An. cracens) and Anopheles maculatus (An. maculatus) from knowlesi malaria endemic areas in Peninsular Malaysia towards DDT, malathion and deltamethrin and to determine the resistance mechanism involved. Methods: Adult and larval mosquitos were collected for surveillance. Susceptibility status of Anopheles was determined using the standard WHO adult bioassay, larval bioassay and biochemical enzyme assay. Results: WHO adult bioassay results indicated An. cracens collected from Kampung Sungai Ular, Pahang was resistant towards 4% DDT, while An. maculatus collected from Kampung Sokor, Kelantan and Kampung Sungai Lui, Selangor exhibited resistance towards 4% DDT. However, the enzyme activity profiles varied according to strains and species. The resistance ratio of larval bioassay, showed that all strains and species tested were susceptible to malathion and temephos. Conclusions: Since only a few anopheline strains exhibited low level of insecticide resistance towards malathion, DDT and temephos. These insecticides are still considered effective for vector control program towards An. cracens and An. maculatus.

Urbanization results in the increment of construction waste, which eventually contaminate the surrounding environment and affects the ecosystem. This study aimed to investigate the potential toxic effects of construction waste runoff collected from an illegal construction waste dumping site, Kampung Sungai Pelong, Malaysia by using brine shrimp (Artemia sp.) and zebrqfish (Danio rerio). The runoff sample collected in January 2018 proceeded with the physicochemical test, heavy metal analysis and bio-toxicity study. Several physicochemical properties (BOD, TSS, NH3JV and NO3-) and heavy metal content (Cu>Cd>Ni>As>Pb>Cr>Hg) of runoff had values significantly exceeding the respective Class IIA Malaysia National Water Quality Standards. No mortality and abnormal swimming behaviour were observed for brine shrimp acute assay, but severely damage appendages and pigmentation were evident. In the zebrqfish sub-acute assay, no constant trend of mortality was observed, but abnormal swimming pattern and alterations in gill tissue (cell vacuolation and clubbed tips). The results signify the potential eco-toxicity caused by construction waste runoff and urge the need for long-term toxicity study and strict legislative actions by the local authority.