Microwave-assisted alkali pretreatment of itchgrass for fermentable sugar production
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Abstract
Itchgrass, a relatively abundant weed in the Philippine cropland, was explored as a potential source of fermentable sugars. Microwave-assisted alkali pretreatment was used as a pretreatment method for itchgrass. The results showed that the treatment with high NaOH concentration (5% w/v), exposed to high microwave irradiation power (300 W), and subjected to a long reaction time (9 min) produced the most reducing sugar after pretreatment and saccharification. Additionally, the characterization of the pretreated itchgrass showed that 47.83% of the original lignin content and 41.02% of the original hemicellulose were removed after the pretreatment. Moreover, the microwave-assisted alkali pretreatment of itchgrass produced more reducing sugar after pretreatment and saccharification compared to the itchgrass pretreated with conventional heating alkali pretreatment. Overall results suggest that itchgrass is a good potential source of fermentable sugars, especially when pretreated using microwave-assisted alkali pretreatment.
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