**8. Conclusion**

*Fusarium oxysporum* cultures were grown on *B. vulgaris* waste to facilitate the biodegradation of cyanide, with the initial concentration of the cyanide being 500 mg CN- /L. The wastewater used was similar to the effluent discharged into ponds by goldmines having metals such as arsenic, copper, lead, iron and zinc.

The response surface plot identified temperature as a more significant factor affecting both the cyanide degradation and ammonium-nitrogen formation. The ammonium-nitrogen produced can be used as a nitrogen source by the fungus.

The optimum condition for maximum cyanide degradation and minimum ammoniumnitrogen formation was found at temperature 30o C and pH of 11 where cyanide of 250.436 mg F-CN/L was degraded and ammonium-nitrogen of 74.285 mg NH4 + -N/L was formed.
