Conclusion
In conclusion, H. polyrhizus fruit extract is relatively safe when
given orally. Oral administration of a methanol extract of H. polyrhizus
fruit at 1250, 2500 and 5000 mg/kg per day to both male
and female rats for 28 days did not result in mortality and was
not associated with adverse effects on the general condition,
growth, organ weights, or hematological and biochemical parameters,
nor did it show abnormalities in macroscopic or histopathological
findings. Thus, its lethal oral dose for male and female rats
exceeds 5000 mg/kg. According to Faustman and Omenn (2001),
the no-observed-adverse-effect level (NOAEL) is the highest exposure
level at which there is no statistically or biologically significant
increase in the frequency or severity of adverse effects
between exposed and control groups. Some effects may be produced
but they are not considered adverse or precursors to adverse
effects. The NOAEL for rats in the present study was 5000 mg/kg
per day. This study provides valuable preliminary data on the toxicity
profile of H. polyrhizus fruit. Further investigations involving
pre-clinical and clinical studies of the extract will be necessary to
determine the safe dose before it is prescribed as a drug, in order
to protect the population from the possible toxic effects of this
fruit.