用于质谱检测的芝麻过敏原高效提取方法比较

Comparison of Efficient Extraction Methods for Sesame Allergens for Mass Spectrometry Detection

摘要:

芝麻是八大类过敏原食物之一，近年来随着芝麻及其衍生产品销量的持续增长，芝麻过敏病例逐渐上升，因此对芝麻过敏原的检测尤为重要。质谱法可以实现过敏原精准检测，而过敏原蛋白的高效提取是其有效识别的前提和基础。目前，主要以芝麻榨油副产物或生芝麻为研究对象进行芝麻蛋白提取优化研究。为了深入探究加工食品中芝麻过敏原蛋白的提取方法，以生芝麻、熟芝麻及芝麻加工制品为靶标，优化芝麻蛋白提取条件。根据蛋白粗提液中质谱鉴定等结果，确定加工制品中芝麻蛋白的最佳提取方法。结果表明，使用尿素缓冲溶液（50 mmol•L-1 Tris-HCl+7 mol•L-1尿素+2 mol•L-1硫脲+质量分数4% CHAPS，pH值8.5），在振荡结合超声提取40 min的条件下，可有效提取加工制品中芝麻蛋白。即使是经过加工的熟芝麻，蛋白提取质量浓度也可达到20 mg•mL-1以上。使用该蛋白提取条件能高效提取加工制品中芝麻蛋白，为质谱法痕量检测芝麻过敏原提供技术支撑，有助于芝麻过敏原标签标识的建立。

Abstract:

Sesame is one of the eight major allergenic foods, and with the increasing consumption of sesame-based products in recent years, the incidence of sesame allergy has risen accordingly. Accurate detection of sesame allergens is therefore of crucial importance for food safety. Mass spectrometry provides a reliable approach for allergen identification; however, efficient extraction of allergenic proteins is a critical prerequisite for successful detection. Most existing studies on sesame protein extraction focus on raw sesame seeds or sesame oil by-products. To optimize extraction methods for sesame allergens in processed foods, both raw sesame and processed sesame products were used as test samples. Based on mass spectrometric identification of proteins in crude extracts, an optimal extraction method for sesame allergen proteins in processed products was established. The results showed that sesame proteins from processed products could be effectively extracted using a urea-based buffer system (50 mmol•L-1 Tris-HCl, 7 mol•L-1 urea, 2 mol•L-1 thiourea, and 4 wt.% CHAPS, pH value 8.5) combined with shaking and ultrasonic treatment for 40 min. Under these conditions, protein concentrations exceeding 20 mg•mL-1 were obtained, even from processed sesame samples. Efficient extraction of sesame proteins under these conditions provides technical support for trace detection of sesame allergens using mass spectrometry and contributes to the establishment of accurate sesame allergen labelling.