Effect of glucose and nitrogen source on caffeine degradation by four filamentous fungi

Abstract

A time bound study of caffeine degradation by fungi, <i style="mso-bidi-font-style:normal">viz.</i>, <i style="mso-bidi-font-style: normal">Chrysosporium keratinophilum</i>,<i style="mso-bidi-font-style:normal"> Gliocladium roseum</i>,<i style="mso-bidi-font-style:normal"> Fusarium solani </i>and <i style="mso-bidi-font-style:normal">Aspergillus restrictus</i>,<i style="mso-bidi-font-style:normal"> </i>isolated from the coffee pulp was undertaken. The degradation was studied at 1 g/L concentration of caffeine with 1-8 g/L glucose, and with or without nitrogen (NH₄Cl) source at 2 g/L in minimal liquid medium by subjecting to shake flask culture at 120 rpm and 30<span style="mso-bidi-font-family:" times="" new="" roman""="" lang="EN-GB">°C. The caffeine degradation was analyzed up to 7 d at 24 h interval by HPLC. It is evident from the present study that varying concentrations of glucose did not affect the caffeine degradation by all the four test fungi. Over all, <i style="mso-bidi-font-style:normal">C. keratinophilum </i>showed significantly<i style="mso-bidi-font-style:normal"> </i>higher rate of caffeine degradation compared to other test fungi, irrespective of presence or absence of nitrogen source in the medium. However, the caffeine degradation by <i style="mso-bidi-font-style:normal">C. keratinophilum </i>was on the higher side in the absence of nitrogen source. In contrast,<i style="mso-bidi-font-style: normal"> G. roseum, F. solani</i> and <i style="mso-bidi-font-style:normal">A. restrictus</i> showed better rate of caffeine degradation in the presence of nitrogen source in the medium.

</span>