<span style="font-size:11.0pt;font-family: "Times New Roman";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;mso-ansi-language:EN-GB;mso-fareast-language:EN-US;mso-bidi-language: HI" lang="EN-GB">Optimization of microwave pretreatment and enzymatic hydrolysis of pith bagasse with <i><span style="font-size:11.0pt; font-family:"Times New Roman";mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:Mangal;mso-ansi-language:EN-GB;mso-fareast-language:EN-US; mso-bidi-language:AR-EG" lang="EN-GB">Trichoderma</span></i><span style="font-size:11.0pt;font-family:"Times New Roman";mso-fareast-font-family: "Times New Roman";mso-bidi-font-family:Mangal;mso-ansi-language:EN-GB; mso-fareast-language:EN-US;mso-bidi-language:AR-EG" lang="EN-GB"> cellulase</span></span>

Abstract

Pith bagasse was subjected to microwave/chemical pretreatments at 900 W under atmospheric pressure for a short time (2-6 min) through several cycles (30 sec/cycle).<span style="mso-bidi-language:AR-EG" lang="EN-GB"> The pith bagasse lost about 48, 21 and 40% of its wt after treatment with microwave/NaOH, microwave/H₂SO₄and microwave/H₂O₂/acetic acid, respectively. Enzymatic hydrolysis of pretreated substrates with <i>Trichoderma</i> cellulase<span style="mso-bidi-language:AR-EG" lang="EN-GB"> indicated that pith bagasse pretreated with microwave/H₂O₂/acetic acid and microwave/NaOH had the highest hydrolysis rate and sugar yield. The mean value for the total reducing sugars (TRS) and glucose yields from both treatments are approx 4 to 5 times than microwave/H₂SO₄ pretreated sample.<span style="mso-bidi-language:AR-EG" lang="EN-GB"> Optimization of treatment process using Box-Behnken design at 6 and 24 h showed that the linear and quadratic terms of the 3 variables tested [H₂O₂/acetic acid treatment time (X₁), solid:liquid ratio (X₂) and microwave treatment time (X₃)]<span style="mso-bidi-language:AR-EG" lang="EN-GB"> had significant effects. Maximal concentrations of TRS and glucose (22 and 18.33 mg/mL, respectively) could be obtained after 24 h hydrolysis time when X_1, X₂andX₃<span style="mso-bidi-language:AR-EG" lang="EN-GB"> were set at 60 min, 1:20 (w/v) and 4 min, respectively. The yield of TRS reached about 99% (g/g total dry matter).

</span></span></span></span></span>