title: Kocuran, an exopolysaccharide isolated from Kocuria rosea strain BS-1 and evaluation of its in vitro immunosuppression activities.
abstract: In an ongoing survey for bioactive potential of microorganisms from different biosphere zones of India, a promising Kocuria rosea strain BS-1 was identified which produced an exopolysaccharide (designated as Kocuran) exhibiting in vitro antioxidant and immunosuppression properties. Kocuran was characterized as a heteropolysaccharide with repeating monosaccharide residues of glucose, galactose, mannose and glucuronic acid with an average molecular mass of 51.2 kDa. In RAW 264.7 macrophages, Kocuran significantly downregulated the LPS-stimulated ROS, NO, TNF-α, IL-6 and C3 complement component secretion to 4.71±0.08%, 4.11±0.06%, 11.19±0.06 pg ml⁻¹, 9.12±0.07 pg ml⁻¹ and 20.81±0.06 ng/10⁶ cells ml⁻¹, respectively. Furthermore, it inhibited the PHA-stimulated proliferation of human peripheral blood mononuclear cells with IC₅₀ of 100.13±2.1 μg ml⁻¹. In addition, the classical and alternative pathway mediated hemolysis was also inhibited with CH₅₀ and AH₅₀ of 100.96±1.75 and 98.60±1.93 μg ml⁻¹, respectively. Kocuran did not inhibit the LPS-induced LAL enzyme and the binding of FITC-LPS to macrophages suggesting that Kocuran does not neutralize the LPS activity. These results demonstrate the in vitro suppression of activation and macrophage-derived inflammatory cytokines and complement mediated hemolysis indicating its in vitro immunosuppression activity.
authors.affiliation: Academy of Scientific and Innovative Research, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad 500007, India; Medicinal Chemistry and Pharmacology Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad 500007, India. Electronic address: cgkumar@iict.res.in.
authors.forename: C Ganesh
authors.initials: CG
authors.lastname: Kumar
authors.affiliation: Academy of Scientific and Innovative Research, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad 500007, India; Medicinal Chemistry and Pharmacology Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad 500007, India.
authors.forename: Pombala
authors.initials: P
authors.lastname: Sujitha
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002240:Carbohydrate Sequence; D002460:Cell Line; D003167:Complement Activation / Q000187:drug effects; D051056:Complement Inactivating Agents / Q000302:isolation & purification / Q000494:pharmacology; D003165:Complement System Proteins / Q000187:drug effects; D016207:Cytokines / Q000378:metabolism; D004353:Drug Evaluation, Preclinical; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D007166:Immunosuppressive Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D020128:Inhibitory Concentration 50; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008835:Micrococcaceae / Q000737:chemistry*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009005:Monosaccharides / Q000032:analysis; D009569:Nitric Oxide / Q000096:biosynthesis; D010835:Phytohemagglutinins / Q000494:pharmacology; D011135:Polysaccharides, Bacterial / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000975:Antioxidants; D051056:Complement Inactivating Agents; D016207:Cytokines; D007166:Immunosuppressive Agents; C000591383:Kocuran; D008070:Lipopolysaccharides; D009005:Monosaccharides; D010835:Phytohemagglutinins; D011135:Polysaccharides, Bacterial; D017382:Reactive Oxygen Species; D009569:Nitric Oxide; D003165:Complement System Proteins
keywords: Antioxidant; Immunosuppression; Kocuran; Kocuria; Macrophages