5novel Lactobacillus ginsenosidimutans was first isolated from kimchi, a traditional Korean side dish.
Lactobacillus ginsenosidimutans: An overview
In a study to determine the ginsenoside-reducing ability of Lactobacillus species, a novel bacterial species with low sequence similarity to other Lactobacillus species was isolated. During the study, this bacterial species was referred to as EMML 3041T. The name Lactobacillus ginsenosidimutans has now been proposed for this novel bacterial species.
Bacterial culturing and isolation
Bacteria obtained from 20 samples of kimchi were cultured and analyzed via the following steps-
- The collected kimchi was first suspended in a 50mM phosphate buffer, having a pH of 7.0.
- The obtained extract was plated onto modified MRS agar plates and then kept for incubation at room temperature for 2 weeks.
- Single colonies that were obtained were then plated onto new modified MRS agar plates and then subsequently transferred to a conventional MRS agar plate.
- To determine the ginsenoside reduction by these bacteria, they were extracted and incubated in an MRS broth containing 1 mg/mL of Rb1 ginsenoside.
Commercially available conventional MRS broth.
Biochemical and morphological characteristics of the isolated strain
The newly isolated bacterial species exhibited great similarity to bacterial species belonging to the genus Lactobacillus. Some of these common characteristics include-
- Gram-positive in nature; the presence of a peptidoglycan layer and absence of an outer lipid membrane.
- Facultatively anaerobic
- Catalase-negative; such bacteria do not employ oxygen as a terminal electron receptor during the respiration process.
It is important to note that apart from just these morphological and biochemical similarities, analytical methods such as 16s RNA sequence analysis and the neighbor-joining method were used to establish the relationship between the novel isolated bacterium and the genus Lactobacillus.
Some of the distinct features of this newly isolated bacterial species are its ability to ferment L-arabinose and methyl D-glucoside.
Structure of L-Arabinose.
What is a ginsenoside?
To understand the significance of the novel species Lactobacillus ginsenosidimutans, it is imperative to understand the reason behind the desirability of ginsenoside-reducing bacteria. Ginsenosides are the predominant biochemical component of ginseng. They have important pharmacological features such as anti-inflammation.
Ginseng: Its health benefits
Ginseng is a slow-growing herb with fleshy roots and oval-shaped leaves with a stalky stem. It refers to 11 different varieties of root plants. Both Asian ginseng (Panax ginseng) and American ginseng (Panax quinquefolius) provide the following health benefits-
- Increase in energy levels- studies have shown that ginseng helps to reduce chronic fatigue and boosts energy levels.
- Improved cognitive function- studies have shown that continuous consumption of Korean red ginseng can improve frontal lobe functioning.
- Lowering of blood sugar- ginseng has been proved to lower blood sugar by increasing insulin resistance in the pancreas.
It is important to note that ginsenosides are known for their antioxidant, anticancer, and immunostimulatory properties. However, current studies are focused on the anti-inflammatory properties of ginsenosides. They possess the ability to inhibit inflammation-related cytokines. When studied using animal models, ginsenosides exhibited great promise in the mitigation of colitis and hepatitis induced by alcohol consumption. Animal models with inflammatory diseases were administered with ginsenosides and the results obtained established the strong anti-inflammatory property of the biochemical compound. Due to the aforementioned health benefits, ginsenosides are pharmacologically significant.
Roots of Asian Ginseng
Kimchi: The source of Lactobacillus ginsenosidimutans
Kimchi is a traditional Korean side dish that consists of fermented and salted vegetables such as cabbage and radish. Several spices are used in the process of kimchi preparation, including Korean chili powder, garlic, ginger, and salted seafood. Kimchi is also used in the preparation of stews and soups.
There are more than a hundred different varieties of kimchi with different vegetable and spice variants. Winter kimchi, also called kimjang, is stored in an underground earthen vessel called “onggi” to prevent it from freezing and drying up. The fermentation process is assisted majorly by fermentative bacteria such as Lactobacillus bacteria, making it a good source of these probiotic bacteria.
Traditionally-made Korean kimchi
Lactobacillus ginsenosidimutans is novel bacterial species that could be pharmacologically significant due to its ability to transform ginsenosides. It exhibits great similarity to most Lactobacillus species but also has the distinct ability to reduce L-arabinose and methyl D-glucoside, making it different from other Lactobacillus species. It was first isolated from kimchi, suggesting that it plays a major role in the fermentation of the dish, giving it its distinct sour taste and pungent odor.