Related Experiment Videos
Amine production by Streptococcus lactis under different growth conditions
H Chander1, V K Batish, S Babu
1Dairy Bacteriology Division, National Dairy Research Institute, Haryana, India.
Acta Microbiologica Polonica
|January 1, 1988
Summary
Streptococcus lactis produces the most histamine, tyramine, and tryptamine at 30°C, pH 5.0, and without NaCl. Salt addition, even at low concentrations, inhibits amine synthesis.
Area of Science:
- Microbiology
- Food Science
- Biochemistry
Background:
- Biogenic amines, such as histamine, tyramine, and tryptamine, are nitrogenous compounds found in various foods.
- Their production by microorganisms can impact food quality and safety.
- Lactic acid bacteria (LAB), including Streptococcus lactis, are known producers of these amines.
Purpose of the Study:
- To investigate the optimal conditions for the production of histamine, tyramine, and tryptamine by Streptococcus lactis.
- To determine the effect of sodium chloride (NaCl) concentration on the synthesis of these biogenic amines.
Main Methods:
- Culturing Streptococcus lactis under varying temperature and pH conditions.
- Analyzing the concentration of histamine, tyramine, and tryptamine using appropriate analytical techniques.
- Evaluating the impact of different NaCl concentrations on amine production.
Main Results:
- The highest production of histamine, tyramine, and tryptamine by S. lactis occurred at 30°C, pH 5.0, and within 24 hours.
- Maximum amine levels were observed in a growth medium devoid of NaCl.
- Even a low concentration of 0.5% NaCl exhibited a slight inhibitory effect on the synthesis of these amines.
Conclusions:
- Optimal conditions for S. lactis amine production involve moderate temperatures and acidic pH, with a complete absence of NaCl.
- Sodium chloride plays an inhibitory role in the biosynthesis of these key biogenic amines by S. lactis.
- Understanding these factors is crucial for controlling amine formation in fermented foods.