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MICROBIOLOGY AND VIROLOGY / CLINICAL RESEARCH
Investigating the multi-targeted pharmacological profile of an exopolysaccharide from Bacillus rugosus SYG20 via in vitro evaluation of its antioxidant, anti-inflammatory, antidiabetic, wound healing, and antimicrobial properties
1
Department of Biology, College of Science, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
2
Medical Lab Technology Department, Faculty of Medical Technology, Wadi-Al-Shatii University, Brack, Libya
3
Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
4
Laboratory and Blood Bank Department, Prince Sultan Military Armed Forces, Madinah, Saudi Arabia
5
College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
6
Faculty of Nursing, Port Said University, Port Said, Egypt
7
Department of Basic Medical Sciences, College of Medicine, AlMaarefa University, Riyadh, Saudi Arabia
8
Department of Medical Biochemistry, Faculty of Medicine, Mansoura University, Mansoura, Egypt
9
Department of Medical Microbiology, Faculty of Medicine, University of Tabuk, Tabuk, Saudi Arabia
10
Microbiology and Immunology Department, Faculty of Pharmacy, Egyptian Russian University, Cairo, Egypt
11
Department of Clinical Microbiology and Immunology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
12
Botany and Microbiology Department, Faculty of Science, Suez Canal University, Ismailia, Egypt
Submission date: 2024-02-10
Final revision date: 2024-05-22
Acceptance date: 2024-06-13
Online publication date: 2024-07-03
Corresponding author
Ahmed Ghareeb
Botany and Microbiology Department Faculty of Science Suez Canal University Ismailia 41522, Egypt
Botany and Microbiology Department Faculty of Science Suez Canal University Ismailia 41522, Egypt
Arch Med Sci 2025;21(6):2389-2405
KEYWORDS
TOPICS
ABSTRACT
Introduction:
Exopolysaccharides (EPSs) derived from marine microorganisms are a newly recognized reservoir of bioactive therapeutic compounds.
Material and methods:
We isolated a high EPS-yielding bacterial strain from the Red Sea, identified as Bacillus rugosus SYG20. Its purified EPS (EPSR9) contains 45.33% uronic acid, 9.98% sulfate groups, and 5.40% N-acetyl glucosamine. The HPLC chromatogram revealed four monosaccharides – glucose, xylose, galacturonic acid, and arabinose, in a distinct molar ratio of 2 : 3 : 1 : 1. EPSR9 showed a wide array of bioactivities.
Results:
It displayed antioxidant activity with an IC50 of 25.6 µg/ml in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and a total antioxidant capacity (TAC) of 417.77 µg/ml ascorbic acid equivalent (AAE) and 62.67 µg/ml AAE in ferric reducing antioxidant power (FRAP) assays. It exhibited substantial anti-inflammatory properties by inhibiting 81.8–99% of hypotonic solution-induced hemolysis of human red blood cells (HRBCs) at 100–1000 µg/ml. The anticoagulant effect of the EPS was demonstrated by a dose-dependent increase in prothrombin time from 18.7 to 49.3 s and partial thromboplastin time from 33.5 to 60.3 s at 25–75 µg/ml. The scratch assay resulted in a 72.66% increase in wound closure, promoting in vitro wound healing after 48 h. Anti-obesity activity was evidenced by 83.8% lipase inhibition at 1000 µg/ml with IC50 of 107.73 µg/ml. EPSR9 demonstrated inhibitory effects on -amylase with an IC50 value of 14.37 µg/ml and -glucosidase with an IC50 value of 26.73 µg/ml, highlighting its potential as an antidiabetic agent. Then, EPS showed bactericidal properties with MBC/MIC ≤ 2 against both Gram-positive (G+ve) and Gram-negative (G-ve) bacteria, Staphylococcus aureus (MIC = 62.5 µg/ml), Enterococcus faecalis (MIC = 3.9 µg/ml), Salmonella typhi (MIC = 31.25 µg/ml), and Helicobacter pylori (MIC = 31.25 µg/ml). Additionally, it showed concentration-dependent anti-biofilm activity, achieving up to 88% for Salmonella typhi, 86.08% for Klebsiella pneumoniae, and remarkable antibiofilm activity at 95.60 % for H. pylori at 75% MBC.
Conclusions:
The marine EPSR9 exhibited considerable potential for pharmaceutical applications as a multi-bioactive microbial metabolite. Its in vivo potency and mechanisms of action warrant further investigation.
Exopolysaccharides (EPSs) derived from marine microorganisms are a newly recognized reservoir of bioactive therapeutic compounds.
Material and methods:
We isolated a high EPS-yielding bacterial strain from the Red Sea, identified as Bacillus rugosus SYG20. Its purified EPS (EPSR9) contains 45.33% uronic acid, 9.98% sulfate groups, and 5.40% N-acetyl glucosamine. The HPLC chromatogram revealed four monosaccharides – glucose, xylose, galacturonic acid, and arabinose, in a distinct molar ratio of 2 : 3 : 1 : 1. EPSR9 showed a wide array of bioactivities.
Results:
It displayed antioxidant activity with an IC50 of 25.6 µg/ml in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and a total antioxidant capacity (TAC) of 417.77 µg/ml ascorbic acid equivalent (AAE) and 62.67 µg/ml AAE in ferric reducing antioxidant power (FRAP) assays. It exhibited substantial anti-inflammatory properties by inhibiting 81.8–99% of hypotonic solution-induced hemolysis of human red blood cells (HRBCs) at 100–1000 µg/ml. The anticoagulant effect of the EPS was demonstrated by a dose-dependent increase in prothrombin time from 18.7 to 49.3 s and partial thromboplastin time from 33.5 to 60.3 s at 25–75 µg/ml. The scratch assay resulted in a 72.66% increase in wound closure, promoting in vitro wound healing after 48 h. Anti-obesity activity was evidenced by 83.8% lipase inhibition at 1000 µg/ml with IC50 of 107.73 µg/ml. EPSR9 demonstrated inhibitory effects on -amylase with an IC50 value of 14.37 µg/ml and -glucosidase with an IC50 value of 26.73 µg/ml, highlighting its potential as an antidiabetic agent. Then, EPS showed bactericidal properties with MBC/MIC ≤ 2 against both Gram-positive (G+ve) and Gram-negative (G-ve) bacteria, Staphylococcus aureus (MIC = 62.5 µg/ml), Enterococcus faecalis (MIC = 3.9 µg/ml), Salmonella typhi (MIC = 31.25 µg/ml), and Helicobacter pylori (MIC = 31.25 µg/ml). Additionally, it showed concentration-dependent anti-biofilm activity, achieving up to 88% for Salmonella typhi, 86.08% for Klebsiella pneumoniae, and remarkable antibiofilm activity at 95.60 % for H. pylori at 75% MBC.
Conclusions:
The marine EPSR9 exhibited considerable potential for pharmaceutical applications as a multi-bioactive microbial metabolite. Its in vivo potency and mechanisms of action warrant further investigation.
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| ISSN: | 1734-1922 |
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