Bano Shaher, Sommano Sarana Rose, Leksawasdi Noppol, Taesuwan Siraphat, Rachtanapun Pornchai, Techapun Charin, Sumonsiri Nutsuda, Khemacheewakul Julaluk
Division of Food Science and Technology, School of Agro-Industry, Faculty of Agro-Industry, Chiang Mai University, Chiang Mai 50100, Thailand.
Plant Bioactive Compound Laboratory (BAC), Department of Plant and Soil Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand.
Foods. 2025 Jun 17;14(12):2118. doi: 10.3390/foods14122118.
Green soybeans, or edamame ( L. Merril), serve as a superior source of phytochemicals and other nutritive substances and are commonly used as ingredients and additives in food products due to their polyphenols' functional properties and antioxidant activity. Hence, it is very important to use a process to extract compounds with functional roles from plants as efficiently as possible. In this study, we sought to identify the optimal conditions for extracting genistein, belonging to the aglycone subgroup of isoflavones, from edamame using the cold plasma (CP) and enzyme method. Additionally, the impact of various drying techniques (spray-drying and freeze-drying) and storage conditions on the crude genistein extract powder was evaluated. The findings showed that the maximum values for the total phenolic content (TPC), total flavonoid content (TFC), and genistein (22.5 ± 0.23 mg of gallic acid equivalents (GAE)/100 g; 15.3 ± 0.13 mg of catechin equivalents (CAE)/100 g; and 12.6 ± 0.10 mg/100 g, respectively) were achieved under optimal pretreatment conditions using a CP gas flow rate of 5 L/min for 30 min, followed by enzymatic treatment at a specific enzyme concentration of 2.0% (/) for 240 min of incubation. Moreover, a scanning electron microscopy (SEM) analysis demonstrated that the CP and enzyme treatment induced significant structural changes, as evidenced by the presence of deeper pores on the surface of the powder granules. Spray-drying demonstrated a superior efficacy compared to freeze-drying for encapsulating the crude isoflavone extract. This study's results also demonstrated that storage at 4 °C significantly stabilized the TPC, TFC, and genistein content and the antioxidant activity while preserving the physical properties (solubility and color) of the crude extract powder for up to 45 days. In summary, cold plasma pretreatment and enzymatic treatments offer practical solutions by enhancing the efficiency of non-thermal extraction processes, thereby increasing the yield of bioactive compounds, maintaining quality, and diminishing reliance on traditional, harsh methods. The elevated genistein content in the crude extract powder indicates its prospective application as a functional ingredient in various food and nutraceutical contexts.
青豆，即毛豆（L. Merril），是植物化学物质和其他营养物质的优质来源，由于其多酚的功能特性和抗氧化活性，常用于食品中的成分和添加剂。因此，采用一种尽可能高效地从植物中提取具有功能作用的化合物的方法非常重要。在本研究中，我们试图确定使用冷等离子体（CP）和酶法从毛豆中提取属于异黄酮苷元亚组的染料木黄酮的最佳条件。此外，还评估了各种干燥技术（喷雾干燥和冷冻干燥）和储存条件对粗染料木黄酮提取物粉末的影响。研究结果表明，在最佳预处理条件下，使用5 L/min的CP气体流速处理30分钟，然后在特定酶浓度为2.0%（/）的条件下进行240分钟的酶处理，总酚含量（TPC）、总黄酮含量（TFC）和染料木黄酮（分别为22.5±0.23毫克没食子酸当量（GAE）/100克；15.3±0.13毫克儿茶素当量（CAE）/100克；以及12.6±0.10毫克/100克）达到最大值。此外，扫描电子显微镜（SEM）分析表明，CP和酶处理引起了显著的结构变化，粉末颗粒表面出现更深的孔隙就是证明。在包封粗异黄酮提取物方面，喷雾干燥显示出比冷冻干燥更好的效果。本研究结果还表明，在4℃下储存可显著稳定TPC、TFC和染料木黄酮含量以及抗氧化活性，同时在长达45天的时间内保持粗提取物粉末的物理性质（溶解性和颜色）。总之，冷等离子体预处理和酶处理通过提高非热提取过程的效率提供了切实可行的解决方案，从而提高了生物活性化合物的产量，保持了质量，并减少了对传统苛刻方法的依赖。粗提取物粉末中染料木黄酮含量的提高表明其在各种食品和营养保健品领域作为功能成分的潜在应用前景。
