• Energy Research
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AbstractAreca nut husk (ANH) holds promise as a viable biomass source for xylose production. Xylose is a precursor for various biochemicals. However, the recalcitrant nature of ANH makes saccharification more complex. To address this, lime and acid pretreatments were carried out to enhance the susceptibility of biomass to saccharification. Before this, a compositional analysis was conducted to determine the initial constituents of the feedstock. Saccharification was conducted under the following conditions: 2% (wV−1) substrate loading, 100 rpm agitation, and 30 °C hydrolysis temperature for 12 h hydrolysis time at pH 4.5 to 5.0. However, parameters like xylanase enzyme loading were varied to enhance the saccharification of the ANH. The results demonstrated that acid‐treated husk (ATH), lime‐treated husk (LTH), and raw husk (RH) achieved the highest yield (gg−1) of reducing sugar, approximately 90, 83, and 15%, respectively, at an enzyme loading of 15.0 IUg−1. Various analytical techniques, including Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), zeta potential, thermogravimetric analysis (TGA), X‐ray diffraction (XRD), and field emission scanning electron microscopy (FESEM) were used to examine structural changes in the native, pretreated, and saccharified residues of ANH. The analysis revealed that a significant amount of partial crystalline and amorphous cellulose in the ANH biomass was hydrolyzed during the saccharification process. However, saccharification also led to the removal of amorphous substances, disruption of the crystalline structure, and conversion of crystalline regions into amorphous domains.

Abstract In this work, potato and sweet lime peels otherwise considered as waste were used as substrates for producing glucose. Different pre-treatment processes were carried out and the best conditions yielding higher amount of glucose concentration were further hydrolysed by enzyme. The pre-treated extract at 80 min in case of dilute acid hydrolysis with autoclaving conditions gave higher glucose concentration amongst all the pre-treatment processes for both the peels and hence considered for further analysis. Rationale for the next step of the experiment was designed based on a central composite statistical design (CCD). To obtain high glucose yield, response surface methodology (RSM) was used to optimize the hydrolysis conditions. The three parameters chosen for the study were; time (h), temperature (oC) and the rotation frequency of the incubator (revolutions per minute i.e. RPM). The optimum conditions in case of potato peel were found to be 56 h, 68 °C and 144 RPM and in case of sweet lime peel, 56 h, 68 °C and 167 RPM. Under these conditions, 46.17 (±0.77) gL−1 and 35.90 (±0.43) gL−1 of glucose were obtained for potato and sweet lime peels respectively. The optimum factors acquired from the statistical model were further confirmed using the experimental results.