Institute of Biotechnology, National Taiwan University, Taipei 10617, Taiwan.
Graduate Institute of Food Science Technology, National Taiwan University, Taipei 10617, Taiwan.
J Food Drug Anal. 2017 Oct;25(4):804-811. doi: 10.1016/j.jfda.2016.12.006. Epub 2017 Feb 16.
Extracellular polysaccharide (EPS) is one of the major bioactive ingredients contributing to the health benefits of Ganoderma spp. In this study, response surface methodology was applied to determine the optimal culture conditions for EPS production of Ganoderma formosanum. The optimum medium composition was found to be at initial pH 5.3, 49.2 g/L of glucose, and 4.9 g/L of yeast extract by implementing a three-factor-three-level Box-Behnken design. Under this condition, the predicted yield of EPS was up to 830.2 mg/L, which was 1.4-fold higher than the one from basic medium (604.5 mg/L). Furthermore, validating the experimental value of EPS production depicted a high correlation (100.4%) with the computational prediction response model. In addition, the percentage of β-glucan, a well-recognized bioactive polysaccharide, in EPS was 53±5.5%, which was higher than that from Ganoderma lucidum in a previous study. Moreover, results of monosaccharide composition analysis indicated that glucose was the major component of G. formosanum EPS, supporting a high β-glucan percentage in EPS. Taken together, this is the first study to investigate the influence of medium composition for G. formosanum EPS production as well as its β-glucan composition.
胞外多糖（EPS）是灵芝属发挥健康功效的主要活性成分之一。本研究采用响应面法确定了灵芝胞外多糖生产的最佳培养条件。通过三因素三水平 Box-Behnken 设计，发现最佳培养基组成为初始 pH 5.3、葡萄糖 49.2 g/L 和酵母提取物 4.9 g/L。在此条件下，EPS 的预测产量高达 830.2 mg/L，是基础培养基（604.5 mg/L）的 1.4 倍。此外，验证实验的 EPS 产量与计算预测响应模型高度相关（100.4%）。此外，EPS 中公认的生物活性多糖β-葡聚糖的百分比为 53±5.5%，高于之前研究中灵芝的含量。此外，单糖组成分析结果表明，葡萄糖是灵芝 EPS 的主要成分，这支持了 EPS 中高β-葡聚糖百分比的说法。综上所述，这是首次研究灵芝胞外多糖生产及其β-葡聚糖组成的培养基组成的影响。
