PH9424 | SM固体培养基（黏菌专用） SM Solid Culture Medium Specific for Myxomycetes

SM培养基（粘菌培养基），外文名为SM medium，是一种用于培养粘菌的培养基。其主要成分为葡萄糖、蛋白胨、酵母膏、硫酸镁、磷酸盐、琼脂组成。

SM 固体培养基是专为细胞性黏菌（如盘基网柄菌 Dictyostelium discoideum 等）设计的标准化营养培养基，广泛应用于黏菌的常规培养、菌种保藏及相关科研实验，是 SCI 论文及专业菌种保藏中心常用的标准培养基配方。该培养基富含蛋白胨、酵母提取物等营养成分，可有效支持黏菌伴生菌（如大肠杆菌）的生长，为黏菌提供充足食物来源；搭配科学配比的磷酸盐缓冲体系和镁盐，能维持培养基 pH 稳定在 6.0–6.5，为黏菌生长、聚集及子实体形成提供适宜的渗透压和营养环境，且无需额外调整 pH，配制便捷、稳定性强，可满足黏菌基础培养及科研实验的严格要求，同时适配黏菌二员培养（与细菌共培养）的常规需求，助力黏菌生长状态的稳定观察与研究。

组分（g/L）

蛋白胨 10.0 g

酵母提取物 1.0 g

D-葡萄糖 10.0 g

磷酸二氢钾 1.9 g

磷酸三钾十二水合物 1.3 g

无水硫酸镁 0.49 g

琼脂 17.0 g

pH：6.0–6.5@25℃

配制方法（1L的用量，实验前建议小样本做预实验）：

1. 称取上述全部成分共 41.69 g，加入约 800 mL 蒸馏水，加热搅拌至完全溶解。

2. 加蒸馏水定容至 1000 mL，测定 pH。此配方磷酸盐缓冲体系合理，通常无需额外调 pH，自然 pH 即落在 6.0–6.5 范围内；若偏差较大再用稀酸/稀碱微调。

3. 将培养基分装至锥形瓶，121 ℃高压蒸汽灭菌 15 分钟。

4. 灭菌后冷却至 50–55 ℃，在超净工作台内倾注平板，静置凝固。

5. 将 SM 平板在超净台内吹干表面水分，均匀涂布活化的大肠杆菌菌液作为黏菌食物源。

6. 在平板中央接种黏菌孢子或原质团，封口后置于 20–24 ℃ 避光培养，每日观察生长及子实体形成情况。

7. 用于菌种保藏时，培养至生长稳定后密封，4 ℃ 短期保存。

SM medium, also known as slime mold medium, is a type of culture medium used for cultivating slime molds. Its main components include glucose, peptone, yeast extract, magnesium sulfate, phosphate, and agar.

SM solid medium is a standardized nutrient medium specifically designed for cellular slime molds such as Dictyostelium discoideum. It is widely used in the routine culture, strain preservation, and related scientific research experiments of slime molds and is a commonly used standard medium formula in SCI papers and professional strain preservation centers. This medium is rich in nutrients such as peptone and yeast extract, which can effectively support the growth of symbiotic bacteria of slime molds (such as Escherichia coli), providing a sufficient food source for slime molds. The scientific ratio of phosphate buffer system and magnesium salts maintains the pH of the medium stable at 6.0–6.5, providing an appropriate osmotic pressure and nutritional environment for the growth, aggregation, and fruiting body formation of slime molds. It does not require additional pH adjustment, is convenient to prepare, and has strong stability, meeting the strict requirements of basic slime mold culture and scientific research experiments. At the same time, it is suitable for the routine needs of slime mold binary culture (co-culture with bacteria), facilitating the stable observation and research of slime mold growth states.

Component (g/L)

Peptone 10.0 g

Yeast extract 1.0 g

D-glucose 10.0 g

Potassium dihydrogen phosphate 1.9 g

Potassium trihydrogen phosphate dodecahydrate 1.3 g

Magnesium sulfate anhydrous 0.49 g

Agar 17.0 g

pH: 6.0–6.5 @ 25℃

Preparation method (for 1L, it is recommended to conduct a pre-experiment with a small sample before the experiment):

Weigh out all the above components totaling 41.69 g, add approximately 800 mL of distilled water, and heat and stir until completely dissolved.

Add distilled water to make up to 1000 mL and measure the pH. This formula for the phosphate buffer system is reasonable and usually does not require additional pH adjustment, as the natural pH typically falls within the range of 6.0–6.5; if the deviation is significant, use dilute acid or dilute alkali for fine-tuning.

3. Pour the culture medium into conical flasks and sterilize at 121 ℃ under high pressure for 15 minutes.

After sterilization, cool to 50–55 ℃ and pour the plates in a laminar flow hood, then let them solidify.

5. Dry the surface moisture of the SM plate in a laminar flow hood and evenly apply the activated Escherichia coli culture as the food source for the slime mold.

6. Inoculate the spores or protoplasts of the slime mold in the center of the plate, seal it, and then place it in the dark at 20–24 ℃ for cultivation. Observe the growth and the formation of fruiting bodies daily.

When used for strain preservation, the culture should be sealed after growth stabilizes and stored at 4 ℃ for short-term preservation.