What bacteria are responsible for smelly body odor?
Body odor
Body odor is influenced by the actions of the skin flora, including members of Corynebacterium, which manufacture enzymes called lipases that break down the lipids in sweat to create smaller molecules like butyric acid. Greater bacteria populations of Corynebacterium jeikeium are for example found more in the armpits of men whereas greater population numbers of Staphylococcus haemolyticus are found in the armpits of women. This causes male armpits to give off of a rancid/cheese-like smell whereas female armpits give off a more fruity/onion-like smell.[7] Staphylococcus hominis is also known for producing thioalcohol compounds that contribute to odors.[8] These smaller molecules smell, and give body odor its characteristic aroma.[9] Propionic acid (propanoic acid) is present in many sweat samples. This acid is a breakdown product of some amino acids by propionibacteria, which thrive in the ducts of adolescent and adult sebaceous glands. Because propionic acid is chemically similar to acetic acid with similar characteristics including odor, body odors may be identified as having a vinegar-like smell by certain people. Isovaleric acid (3-methyl butanoic acid) is the other source of body odor as a result of actions of the bacteria Staphylococcus epidermidis,[10] which is also present in several strong cheese types.
Lactobacillus fermentum
Although LABs have been associated with potential health advantages, they are also responsible for negative outcomes. They are the main organisms involved in the spoilage of tomato products. Species in the genus "Lactobacillus" have been identified to be the causative organisms. Research was carried out to observe the chemical constituents of tomato juice that stimulate the growth of bacteria that are responsible for the spoilage. These bacteria can resist high temperatures. A strain of "Lactobacillus fermentum" was extracted from a tomato juice concentrate. Meanwhile, eight different tomato juice mixtures were heated and the survival rate of "Lactobacillus fermentum" was measured. It was concluded that pectins are the main tomato juice constituents that protect the bacteria cells against destruction from heating. The breakdown of pectin from enzymic action would make the bacteria cells more susceptible to heat. However, it was found in previous research that heating had inactivated natural pectolytic enzymes and therefore "Lactobacillus fermentum " remained heat resistant. Heat resistance has also been found to correlate with the medium in which the bacteria are cultured, the better the medium used will result in a higher resistance to heat.