Production and Optimization Techniques of Bioethanol from Withered Flowers of Allamanda schottii L. by Activated Dry Yeast

Validation of pre-treatments for cost effective production of bioethanol from floral wastes

The present study has focused on validating pre-treatment methods for cost effective production of bioethanol from discarded and otherwise waste flowers which are renewable, abundantly available and eco-friendly. Floral waste was collected from various dumpsites and banquet halls and subjected to physical, chemical and biological pre-treatments. Biological pre-treatment by enzymatic hydrolysis using crude cellulase enzyme (5%) yielded 39.4 ± 0.03 g/L of alcohol which is 24.20 and 31.60% more than the alcohol obtained by physical pre-treatment (thermal hydrolysis) and chemical pre-treatment (1% KOH), therefore simultaneous saccharification and fermentation was optimised. A maximum of 396 ± 6.48 g/L bioethanol was obtained after 96 h of fermentation with the isolated yeast, Pichia kudriavzevii CY 902 at pH 5.5 and 37 °C. The minimum ethanol selling price (MESP) of bioethanol produced in our study was enumerated to be 30.43 Rs/L which is 68.31% lesser than the market price of ethanol in India today, making our methodology for production of bioethanol from mixed floral wastes very competitive and cost effective to the existing methodologies.