Phytochemical analysis and assessment of bioethanol production potential of <i>Cymbopogon schoenanthus</i> (camel grass) under different pH

Abstract

In this research, the phytochemical and bioethanol content of Cymbopogon schoenanthus was assessed under three different pH. The phytochemical screening and proximate analysis was carried out according to standard qualitative and quantitative methods. Where alkaloids, balsam, flavonoids, glycosides, saponin, carbohydrates, Protein, volatile oil, minerals etc. were analyzed. Bioethanol was produced using enzymatic hydrolysis after pretreatment under different pH viz: pH 6, 7 and 8 all under ambient temperature. It was then fermented using Saccharomyces cerevisiae. Each of the treatments was made in triplicates. The absorbance was determined for reducing sugar and at the end of the production it was subjected to Gas chromatography and mass spectroscopy to analyze the end product of bioethanol produced. The result for phytochemicals shows the presence of flavonoids in C. schoenanthus (13%) followed by volatile oil (6.44%). Alkaloids, saponin and tannins are all present. The result for proximate analysis shows highest percentage of carbohydrates (70.69%) followed by ash (11.66%), protein (11.14%), fibres (2.83%). The mineral analysis shows the presence of calcium (1.18 mg/L), magnesium (1.02 mg/L), phosphorous (6.37 mg/L), potassium (1933.33 mg/L) and sodium (59.17 mg/L). The absorbance of reducing sugar was higher at pH8 (0.0679). Same happened to the concentration of the bioethanol. The GC-MS analysis of the bioethanol produced shows the presence of Ethyl alcohol (bioethanol) in all the treatments at different pH. However, Hydrazine carboxamide was present in all the treatments. In addition iso-butane, 1- butanol, butanoic acid and propane were found present, all having fuel potential and are good source of gasoline. These are produced as a result of fermentation and enzymatic activities of the organic compound present in the biomass sample.

Keywords: Bioethanol, Cymbopogon schoenanthus, pH and Phytochemical screening