A high throughput method for total alcohol determination in fermentation broths.

Area of Science:

• Biotechnology
• Analytical Chemistry

Background:

• Traditional potassium dichromate method for alcohol determination is unsuitable for raw fermentation broths due to interfering reducing sugars.
• The dichromate method poses environmental and health risks due to the carcinogenicity of hexavalent chromium (Cr (VI)).

Purpose of the Study:

• To develop a new, accurate, and environmentally friendly method for determining total alcohol concentration in raw fermentation broths.
• To overcome the limitations of existing methods that cannot analyze complex fermentation samples directly.

Main Methods:

• Developed a method involving pretreatment of fermentation broth to remove interfering substances like proteins and organic acids.
• Utilized potassium permanganate oxidation to measure colorimetric changes from both total alcohols and reducing sugars.
• Employed the DNS test to quantify reducing sugars and subtracted this value to isolate the colorimetric change attributed to total alcohols.

Main Results:

• Successfully determined total alcohol concentration in both distilled and raw fermentation broth samples.
• The new method demonstrated accuracy and ease of use for complex biological matrices.
• Achieved a faster and more environmentally friendly analytical process compared to the dichromate method.

Conclusions:

• The developed method provides a reliable way to measure total alcohol content in raw fermentation broths.
• This approach is a significant improvement, offering speed, accuracy, and environmental benefits.
• Enables direct analysis of fermentation samples without extensive purification steps.