Lactobacillus taiwanensis-Erakina

Lactobacillus taiwanensis is a novel bacterial species isolated from silage cattle feed. Through phenotypic and genotypic studies, it was found to belong to the genus Lactobacillus.

What are probiotics?

Probiotics refer to useful bacteria and yeasts that maintain the balance of the gut microbiome and improve digestion. Probiotic bacteria form a symbiotic relationship with the host organism and provide a multitude of benefits to the host. These benefits include-

• Improving gut health
• Maintaining the balance of the gastrointestinal tract.
• Boosting metabolism and supporting the immune system.

Lactobacillus and Bifidobacteria comprise most of the bacteria in the gut microbiome. Food sources of these bacteria include-

• Yoghurt 
• Kimchi 
• Cheese 
• Buttermilk 
• Most fermented foods

SEM image of a species of Bifidobacterium

Probiotics and disease mitigation

Research has proved that probiotics play a major role in mitigating both acute and chronic diseases. Some of the common ailments that can be mitigated via the consumption of probiotics include-

• Diarrhoea 
• Irritable bowel syndrome 
• High cholesterol
• High blood pressure
• Psoriasis 
• Chronic fatigue syndrome

It is important to note that probiotics are different from prebiotics. Prebiotics are present in the food we consume and act as a source of nutrition that supports the growth of bacteria that are part of the gut’s microflora. Some common examples of prebiotics include- bananas, artichokes, soybeans, onions and whole grains.

Genus Lactobacillus: An overview

Lactobacillus bacteria are the most commonly consumed probiotics. These bacteria are also a major component of the microflora of the human body as they are extensively present in the gastrointestinal tract and the female genital system. Lactobacillus bacteria have formed a mutualistic relationship with humans through the course of evolution. These bacteria prevent the entry of pathogens into the human body while the host provides these bacteria with a source of nutrition.

Physiological and morphological characteristics

Lactobacillus bacteria have the following characteristics that make them distinct from other Lactic Acid Bacteria-

• Rod-shaped 
• Non-motile
• Non-spore-forming
• Gram-positive in nature
• Aerotolerant bacteria
• Facultatively anaerobic
• Catalase-negative; such organisms do not respire using oxygen as the terminal electron acceptor.
• Produce lactic acid as a by-product of glucose fermentation.

SEM image of Lactobacillus acidophilus

Lactobacillus taiwanenis: An introduction

Lactobacillus taiwanenis is a novel species of bacteria that was initially isolated from silage cattle feed. Through phylogenetic studies, it was established that this species belongs to the Lactobacillus acidophilus group. 

Physiological and morphological characteristics

Some of the important physiological and morphological characteristics of this bacterial species that make it distinct from other bacterial species and similar to other species that belong to the genus Lactobacillus are as follows-

• Heterofermentative
• Rod-shaped bacteria
• Facultatively anaerobic
• Non-spore forming
• Non-motile
• Catalase negative; these bacteria do not respire using oxygen as the terminal electron acceptor.
• Gram-positive; such bacteria possess a thick outer peptidoglycan layer and no outer lipid membrane, unlike gram-negative bacteria.

In a recent study of Lactobacillus taiwanensis derived from the Peyer’s patches of mice, the following was established-

• This bacterial species could be used as a potential probiotic.
• It is heat-resistant.
• It is resistant to low pH conditions.
• It is resistant to certain bile salts present in the gastrointestinal tract.
• It also improves the efficiency of the immune response in mice.
• This bacterial strain also exhibited antibacterial activity.

What is silage?

Silage refers to a type of feed or fodder provided to ruminant animals such as cattle, sheep and goats. This fodder is usually prepared from green foliage that is fermented to the point of acid production or acidification. The process of fermentation and storage of this fodder is termed ensilage. Some of the most commonly used crops for the purpose of silage production include-

• Grass crops
• Maize
• Sorghums
• Cereals
• Corn 

Several of the bacteria present in the fodder (including Lactobacillus bacteria) produce Volatile Fatty Acids (VFAs) that increase the palatability of the fodder and act as a natural preservative.

Corn silage

Conclusion 

Lactobacillus taiwanenis is a novel bacterial species that exhibit the potential to be used as a probiotic. It maintains gut pH and health in ruminant animals. Phylogenetic studies have established the position of this bacterial strain in the Lactobacillus genus. Studies on mice have also proved that these bacteria are probiotic in nature and also exhibit antibacterial activity.

Deepika Thilakan

13/06/2022