Teratogenic potential of traditional Malaysian vegetables (ulam) in the zebrafish model

Abstract

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 < 0.05, median = 110.7%), while 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 < 0.05, median = 124.3%). On the other hand, 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.