Introduction

Clostridium thermocellum is a type of gram–positive, thermophilic, cellulolytic microorganisms in the Clostridaceae family [1]. This bacterium cell body possesses a solitary lipid bilayer, giving it rod–shaped morphology [2]. G+C content in their genome accounts for approximately 21 to 54 percent [3]. These bacteria reproduce by forming spores and can break down cellobiose and cellulose into ethanol through anaerobic fermentation [4,5]. Clostridium thermocellum offers industrial benefits, as its cellulolytic and ethanologenic potential to transform the cellulosic substrate into ethanol, i.e., to convert biomass into a usable energy source [6,7]. The breakdown of cellulose is achieved within the bacterium using an extracellular cellulase framework called cellulosome [8]. The cellulase framework of the bacterium varies from fungal cellulases because of its capability to solubilize translucent cellulose, e.g., cotton [9]. However, it produces low ethanol yield, due to extended fermentation pathways that produce acetic acid derivatives, formate, and lactate with ethanol [10,11]. New studies have been coordinated to enhance the ethanol–producing metabolic pathway to make more effective biomass transformation [12].

Application of Clostridium thermocellum in Biotechnology

• Renewable resources can be transformed into biofuels and bio–solvents by utilizing Clostridium thermocellum bacterial cultures or cocultures which provide functional factors more effectively than single cultures. For instance, in the co–culture of C. thermocellum JN4 and Thermoanaerobacterium thermosaccharolyticum GD17, the cellulase complex of C. thermocellum JN4 can hydrolyze xylan to xylobiose and xylose yet can't use xylobiose or xylose, however T. thermosaccharolyticum GD17 can use these substrates to produce hydrogen, natural acids and ethanol [13].
• Bioprocesses, in food manufacturing including cheese/yogurt manufacture, Belgian beer production, etc. [14].
• Biodegradation in wastewater treatment and soil bioremediation [15].
• Biofuel production using cellulose or lignin–based feedstock, including rice/wheat straw, corn/sorghum stalk, crude glycerol, banana agro–waste, etc [16].
• Biosynthesis of organic acids, including acetic acid, butyric acid, alcohols, etc [17].

Bacillus coagulans is a bacterium also known as "helpful" bacteria but sometimes is misclassified as lactobacillus since it produces lactic acid [18]. Bacillus coagulans are presented as Lactobacillus sporogenes in a few commercial products [19]. However, it can be easily distinguished from other species from its spores [20].

Application of Bacillus coagulans in Biotechnology

• Bacillus coagulans exhibit a probiotic activity that is impervious to high temperatures [21]. In addition, Bacillus coagulans proteins have been used in food production or incorporated as probiotics in food products [22].
• Bacillus coagulans are incorporated into the food matrix including probiotic yogurt and juice products [23].
• Production of biohydrogen biofuels from agricultural wastewater and molasses using Bacillus coagulans [24].
• Bacillus coagulans are incorporated into medicines for the treatment of diarrhea, constipation, stomach pain, etc [25].

Conclusion

Thus, both the bacterial species, i.e., Clostridium thermocellum and Bacillus coagulans, hold commercial importance in the industrial sector for producing a diversity of products.

Conflict of interest

None

Source of Funding

None.

References

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