1. はじめに
This manual provides essential instructions for the proper preparation, use, and storage of Merck Yeast Extract Agar Medium, Model 113116. This product is designed for microbiological applications, specifically for the enumeration of microorganisms in water samples and other materials, in compliance with ISO 6222 and Swedish Standard SS 028171.
2. 製品の説明
Merck Yeast Extract Agar Medium (Catalog Number 1.13116.0500, 500G) is a dehydrated culture medium used for the general enumeration of heterotrophic microorganisms. Its formulation supports the growth of a wide range of bacteria and yeasts, making it suitable for various microbiological analyses, particularly in water quality testing. The medium is supplied as a fine, homogeneous powder.
図1: Merck Yeast Extract Agar Medium in its original packaging. This image shows the powdered medium within a typical laboratory container, indicating its physical form as supplied.
3. 安全情報
Handle all microbiological media and cultures with appropriate laboratory safety precautions. Wear personal protective equipment (PPE) including lab coats, gloves, and eye protection. Avoid inhalation of the powdered medium. In case of contact with skin or eyes, rinse immediately with plenty of water. Dispose of all contaminated materials and cultures according to local regulations for biohazardous waste.
4. セットアップと準備
- 重量: Accurately weigh the required amount of Yeast Extract Agar Medium powder according to the manufacturer's instructions for the desired volume. Typically, 28 grams of powder are used per liter of distilled water.
- Dissolving: Suspend the weighed powder in the appropriate volume of distilled or deionized water in a suitable flask. Stir thoroughly to ensure the powder is evenly dispersed.
- 加熱： Heat the suspension gently with frequent agitation. Bring to a boil for approximately one minute to completely dissolve the agar. Avoid overheating.
- 殺菌： Autoclave the dissolved medium at 121°C (15 psi) for 15 minutes. Ensure the autoclave cycle is validated and effective.
- 冷却： After sterilization, allow the medium to cool to 45-50°C in a water bath. This temperature is suitable for pouring plates and minimizes condensation.
- 注ぐ： Pour the cooled, sterile medium into sterile Petri dishes on a level surface. Allow the agar to solidify completely before use.
5. 操作手順（使用方法）
- Sampル準備： Prepare your water sample or other material according to standard microbiological methods. This may involve serial dilutions to achieve countable colonies.
- 接種： Inoculate the prepared Yeast Extract Agar plates using appropriate techniques, such as spread plating or pour plating, depending on the specific enumeration method.
- インキュベーション： Incubate the inoculated plates inverted at the specified temperature and duration according to the relevant standard (e.g., 22°C for 72 hours or 37°C for 24-48 hours as per ISO 6222).
- Colony Counting: After incubation, count the visible colonies using a colony counter. Record the results and calculate the microbial count per unit of sampル。
- 解釈： Interpret results in accordance with the applicable microbiological standards and guidelines.
6.メンテナンスと保管
- Dehydrated Medium: Store the dehydrated Merck Yeast Extract Agar Medium powder in its original tightly sealed container in a cool, dry place (e.g., 15-25°C), away from direct light and moisture. Ensure the container is sealed immediately after use to prevent hydration and contamination.
- Prepared Medium: Prepared agar plates can be stored in a refrigerator (2-8°C) for up to 2-4 weeks, provided they are protected from dehydration and contamination. Store plates inverted to minimize condensation on the agar surface.
- 貯蔵寿命： Refer to the product label for the specific expiration date of the dehydrated medium. Do not use expired medium.
7。 トラブルシューティング
| 問題 | 考えられる原因 | 解決 |
|---|---|---|
| Poor or no growth | Incorrect preparation (e.g., wrong concentration, insufficient heating), expired medium, improper incubation conditions, non-viable sampル。 | Verify preparation steps, check expiration date, confirm incubator temperature and time, re-evaluate sample viability. |
| 汚染 | Non-sterile equipment, improper aseptic technique during pouring or inoculation, contaminated water source for medium preparation. | Ensure all equipment is sterile, practice strict aseptic technique, use sterile distilled/deionized water. |
| Agar not solidifying | Insufficient agar concentration, insufficient heating to dissolve agar, incorrect pH. | Check formulation, ensure complete dissolution by boiling, verify pH after preparation. |
8. 仕様
- 製品名: Yeast Extract Agar Medium
- ブランド： メルク
- モデル番号: 113116
- 量： 500G
- カタログ番号: 1.13116.0500
- コンプライアンス： ISO 6222, Swedish Standard SS 028171
- 形状： Dehydrated powder
- ASIN: B0D7ZWHGGZ
- 初回利用可能日: 2024年06月25日
9. 保証とサポート
For detailed warranty information, technical support, or further inquiries regarding Merck Yeast Extract Agar Medium, please refer to the official Merck website or contact your local Merck representative. Product specifications and performance are subject to the manufacturer's terms and conditions.
