山茶籽多肽的发酵制备及其抗氧化和透明质酸酶抑制活性

Fermentation Preparation of Camellia Seed Peptides and Their Antioxidant and Hyaluronidase Inhibitory Activities

摘要:

山茶籽饼是茶油炼制过程的副产物,富含植物蛋白,但尚未被充分开发利用。以山茶籽饼为原料,采用微生物发酵法制备山茶籽多肽,基于多肽得率及抗氧化活性对发酵菌种进行评估,筛选出枯草芽孢杆菌CGMCC NO.29154作为山茶籽多肽发酵菌种。采用正交试验优化了5L反应器发酵工艺参数。结果表明,在基质质量浓度为山茶籽饼粉30g/L(60目)、蔗糖4g/L,发酵转速180r/min、装液量50%、通气量0.30vvm(即1min通气量为发酵液体积的0.30倍)和接种量19%时,发酵22h的多肽得率最高,达到12.15%。此外,发酵所得山茶籽多肽具有良好的抗氧化及透明质酸酶抑制能力。摇瓶和反应器发酵山茶籽多肽清除DPPH自由基的IC₅₀分别为1.18、0.72mg/mL,清除ABTS⁺自由基的IC₅₀分别为0.65、0.52mg/mL,清除羟基自由基的IC₅₀分别为1.18、0.85mg/mL；抑制透明质酸酶活性的IC₅₀分别为4.58、4.17mg/mL,均显著优于未发酵山茶籽饼(P<0.05)。研究结果表明,枯草芽孢杆菌CGMCC NO.29154在发酵山茶籽饼制备生物活性多肽方面具有较好的应用潜力,且该工艺具备放大可行性,希望研究可为山茶籽饼的高值化利用和山茶籽多肽的工业化生产奠定科学基础。

Abstract:

i>Camellia seed cake is an underutilized by-product derived from the Camellia oil refining process, which is a rich source of plant proteins that has not yet been fully exploited. In this study, Camellia seed cake was employed as the raw material for the production of Camellia seed peptides through microbial fermentation. The Bacillus subtilis CGMCC NO.29154 strain was identified as the optimum fermentation strain for Camellia seed peptides by evaluating the peptide yield and antioxidant activity of the fermentation products. An orthogonal experiment was conducted to optimize the fermentation parameters of the peptides in a 5 L bioreactor. The results demonstrated that the highest peptide yield of 12.15% was achieved following 22h of fermentation at a substrate concentration of 30g/L Camellia seed cake powder (60 mesh), 4g/L sucrose, a fermentation rotational speed of 180r/min, a liquid loading rate of 50%, an aeration volume of 0.30vvm (the aeration rate for 1min was 0.30 times the volume of the fermentation broth), and an inoculum volume of 19%. Furthermore, the fermented Camellia seed peptides demonstrated notable antioxidant and hyaluronidase inhibitory activities. The IC₅₀ values for DPPH, ABTS⁺ and hydroxyl radical scavenging were 1.18,0.65 and 1.18mg/mL for shake flask culture and 0.72,0.52 and 0.85mg/mL for bioreactor culture, respectively. The IC₅₀ values for hyaluronidase inhibition were 4.58mg/mL for shake flask culture and 4.17mg/mL for bioreactor culture. All of these values were significantly (P<0.05) superior to those of unfermented Camellia seed cake. The present study indicated that Bacillus subtilis CGMCC NO.29154 had good application potential for preparing bioactive peptides from fermented Camellia seed cake. Further optimization of the fermentation process, including scale-up, could enhance the yield and quality of these peptides, which could in turn lay a scientific foundation for the high-value utilization of Camellia seed cake and the industrial production of Camellia seed peptides.