Potential antitumor and anti-inflammatory activities of an extracellular polymeric substance (EPS) from Bacillus subtilis isolated from a housefly

• Published in: Scientific reports Vol. 12; no. 1; p. 1383
• Main Authors: Zhang, Lingxiu, Yi, Huilan
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 26.01.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 631/154; 631/154/1435; 631/250; 631/250/251; 631/326; 692/308; 692/4017; Animals; Animals, Outbred Strains; Anti-inflammatory agents; Anti-Inflammatory Agents - administration & dosage; Anti-Inflammatory Agents - chemistry; Anti-Inflammatory Agents - metabolism; Antineoplastic Agents - administration & dosage; Antineoplastic Agents - chemistry; Antineoplastic Agents - metabolism; Antioxidants; Antioxidants - administration & dosage; Antioxidants - chemistry; Antioxidants - metabolism; Bacillus subtilis; Bacillus subtilis - isolation & purification; Bacillus subtilis - metabolism; Cell Proliferation - drug effects; Extracellular Polymeric Substance Matrix - chemistry; Extracellular Polymeric Substance Matrix - metabolism; Feed industry; Food industry; Fourier transforms; Free radicals; HeLa Cells; Houseflies - microbiology; Humanities and Social Sciences; Humans; Hydroxyl radicals; Immune system; Inflammation; Infrared spectroscopy; Interleukin 2; Interleukin-2 - metabolism; Lysozyme; Macrophages; Macrophages - drug effects; Macrophages - enzymology; Male; Mice; multidisciplinary; Muramidase - metabolism; Phagocytosis; Phagocytosis - drug effects; Pharmaceutical industry; Polysaccharides, Bacterial - administration & dosage; Polysaccharides, Bacterial - biosynthesis; Probiotics; Probiotics - administration & dosage; Probiotics - metabolism; Reactive oxygen species; Science; Science (multidisciplinary); Signal Transduction - drug effects; Spectroscopy, Fourier Transform Infrared - methods; Spectrum analysis; Ultraviolet spectroscopy
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-022-05143-9

Bacillus subtilis , a probiotic, has been applied in the medical, food, and feed industries among others. However, the mechanisms of its benefits to hosts are not yet fully understood. Here the characterization and bioactivities of an extracellular polymeric substance (EPS) from Bacillus subtilis were investigated to reveal its partial mechanisms and provide the theoretical basics for further development and utilization of Bacillus subtilis . In this study, the novel strain Bacillus subtilis xztubd1 (GenBank: MG458322.1) was isolated from a housefly’s body, identified according to phenotypical and genotypical analyses, and found to produce large amounts of an EPS. Through ultraviolet spectroscopy and Fourier transform infrared spectroscopy (FTIR spectroscopy), the EPS was found to contain a variety of chemical functional groups, such as O–H groups, C=C, C=O, CH 3 , C–O–H and C–O–C bonds, and alpha-type pyranose. Furthermore, the in vitro antioxidant activity of the EPS on DPPH radicals at a concentration of 90 μg/ml was 62%; on the superoxide radical at a concentration of 90 μg/ml, this value was 75%; and on hydroxyl radicals at a concentration of 90 μg/ml, the activity was 54%. EPS also enhanced significantly phagocytosis, lysozyme activity in macrophages, IL-2 content in mice and inhibited dramatically the growth of HeLa cells. These results showed that the EPS with reductive groups have the strong capacity to scavenge reactive oxygen species (ROS), reinforce the immune system and inhibit the growth of cancer cell, which helps theirs hosts defence against many diseases, including inflammation and cancer. The EPS from Bacillus subtilis has the potential to be an anticancer and anti-inflammatory drug candidate in the pharmaceutical industries, which provide scientific evidence for the development and utilization of probiotic-derived medicines.