Mohd Rahimi Ashraf Abd Rahman1, Chin Long Poo1, Norizah Awang1, Nik Aina Syazana Nik Zainuddin1, Nur Liana Md Nasir1, Mei Siu Lau1, Siti Khadijah Mustapha Kamal1, Siti Soleha Ab Dullah1, Maizatul Hasyima Omar1, Hussin Muhammad1*
1. Herbal Medicine Research Centre, Institute for Medical Research, Institute for Medical Research, National Institutes of Health, Ministry of Health Malaysia, 40170 Shah Alam, Selangor, Malaysia
*Corresponding author: Hussin Muhammad.
ABSTRACT
INTRODUCTION: Hibiscus sabdariffa L. has been widely consumed for its antihypertensive, antioxidant, and diuretic properties. However, its potential embryotoxic and teratogenic risks remain unclear. This study investigated the effects of Sí Roja, a product derived from Hibiscus sabdariffa L., on zebrafish embryonic development.
OBJECTIVE(S): The study aimed to assess the embryotoxic and teratogenic effects of Sí Roja using zebrafish (Danio rerio) embryos.
MATERIALS & METHODS: Zebrafish embryos (n = 40 per group) at 6 hours post-fertilisation (hpf) were exposed to Sí Roja at 5, 10, 20, 40, and 80 mg/L. 3,4-Dichloroaniline (DCA) was used as a positive control, while negative and internal controls utilised standard E3 embryo media. Embryotoxicity endpoints (mortality, coagulation, somite formation, tail detachment, and heartbeat) were assessed at 24, 48, and 72 hpf. Teratogenic parameters (head, tail, body shape, yolk deformation, scoliosis, melanin pigmentation, and hatching rate) were evaluated at 48 and 72 hpf. Data were analysed using two-way ANOVA (GraphPad Prism).
RESULTS: Embryotoxicity increased with concentration, with significantly higher mortality at 80 mg/L (p = 0.0054). Only coagulation showed a significant difference (p = 0.0370), while other embryonic endpoints remained unaffected. No structural malformations or scoliosis were observed at any concentration. However, melanin pigmentation and hatching rate were significantly affected at 80 mg/L (p = 0.0153 and p = 0.0370, respectively). DCA confirmed the assay’s sensitivity, while E3 controls showed no significant differences. The no observed effect concentration (NOEC) and lowest observed effect concentration (LOEC) were identified at 40 mg/L and 80 mg/L, respectively.
CONCLUSION: Exposure to Sí Roja at 80 mg/L resulted in significant embryotoxicity, including increased mortality and coagulation, and modest teratogenic effects such as pigmentation changes and delayed hatching. No structural malformations or scoliosis were observed across the tested concentrations. These findings suggest that Sí Roja may be considered developmentally safe at concentrations below 40 mg/L.
KEYWORDS: Sí Roja, Hibiscus sabdariffa, Zebrafish Embryo, Embryotoxicity, Teratogenicity, Herbal Medicine
