본 연구에서는 볏짚의 묽은 황산 가수분해 공정에서 발생하는 생성물을 체계적으로 평가하기 위해  HPLC 기반의 다 중 분석 체계를 구축하고, 이에 따른 가수분해 온도의 영향을 고찰하였다. 당 분석의 정확도를 높이기 위해 이온교환 수지와 비극성 흡착제를 이용한 효율적인 전처리 공정을 적용하였으며, C30 역상 컬럼을 활용하여 지방족 카르복시산, 푸란 유도체 및 페놀 화합물을 동시 정량하였다. 분석 결과, 총당 농도는 140~160℃에서 약 21g/L로 최대치에 도달 하였으나, 180℃에서는 당의 열분해로 인해 감소함과 동시에  5-hydroxymethylfurfural, furfural, vanillin 등 고부가 플랫폼 화합물의 농도가 극대화되는 것을 확인하였다. 특히, 본 분석 시스템을 통해 feruloylated arabinoxylan의 열적 거동을 명확히 규명하였으며, 이는 140℃에서 최대 농도를 보인 후 고온에서 ferulic acid로 전환됨을 알칼리 가수분해 실험을 통해 입증하였다. 본 연구는 고정밀 분석법을 기반으로 주산물과 고단가 부산물의 통합 회수 전략 수립을 위한 핵심 기초 자료를 제공한다.

This study established a comprehensive HPLC-based analytical framework to evaluate the products of dilute sulfuric acid-treated rice straw and investigated the systemic effects of hydrolysis temperature. To ensure analytical precision, a pre-treatment process involving ion-exchange resins and non-polar adsorbents was implemented for sugar analysis. Furthermore, a C30 reversed-phase column was utilized for the simultaneous quantification of aliphatic carboxylic acids, furan derivatives, and phenolic compounds. Analytical results revealed that the total sugar concentration peaked at approximately 21 g/L within 140~160℃, while higher temperatures (180℃) promoted the formation of high-value platform chemicals such as 5-hydroxymethylfurfural, furfural, and vanillin despite sugar degradation. Notably, the analytical system successfully characterized the thermal behavior of feruloylated arabinoxylan, confirming its maximal concentration at 140℃ and subsequent conversion to ferulic acid at higher temperatures through alkaline hydrolysis assays. This study provides essential analytical data for designing integrated recovery processes that balance sugar yield and high-priced chemical byproduct generation.

Rice straw hydrolysate, Sugar analysis, Secondary metabolite analysis, Hydrolysis temperature, feruloy- lated arabinoxylan

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