This study assessed Sabah Mangrove, Rhizophora mucronata leave extract (RMLE) non-clinical safety and pharmacokinetic. APC/YMC count and AMES test, Acute Oral Toxicity, Sub-acute Toxicity, and RMLE Reproductive Toxicity Profiling are evaluated. RMLE's agar plate and heavy metal assay showed that bacteria andfungi, were below the National Pharmaceutical Control Bureau (NPCB) limit. RMLE's antimutagenic properties were tested in AMES experiment employing S. typhimurium TA98. Dose finding test (DFT) plates show no toxicity (growth suppression) for all dosages from 5000 to 313 μg/plate, with and without metabolic activation, for all five tester strains

In acute toxicity study in Sprague dawley rats, single oral dosages of RMLE (2,000 mg/kg) did not cause mortality or behavioural abnormalities. In subacute toxicity trials, RMLE (1,000 mg/kg) for 28 days did not affect body weight increase or behaviour. Hematological and biochemical markers remained unchanged. Histopathology indicated no morphological abnormalities. These findings show that RMLE is safe for medical use.