Abstract: The present invention provides Streptomyces coelicolor strain A3(2)_M22-2C43 obtained by inducing a point mutation in the base sequence of the DagB gene in a wild-type Streptomyces coelicolor strain A3(2) by UV radiation. Since the Streptomyces coelicolor strain A3(2)_M22-2C43 according to the present invention expresses a DagB mutant enzyme expressing little or no DagB beta-agarase or exhibiting little or no beta-agarase activity, there is no need for separate isolation and purification of DagA enzymes from culture fluid, and the culture fluid of the Streptomyces coelicolor strain A3(2)_M22-2C43 or supernatant thereof may be used to produce, from agar or agarose, neoagarose oligosaccharides with a higher content of neoagarotetraose or neoagarohexaose than that of neoagarobiose.

Abstract: Provided in the present invention is a novel use of composition containing a neoagarooligosaccharide mixture as an active ingredient. The neoagarooligosaccharide mixture and the like as an active ingredient of the composition according to the present invention can reduce the expression of RANKL, an osteoclast inducer, or IL-6, an inflammatory cytokine, and effectively inhibit differentiation of monocytes into osteoclasts. Thus, the composition according to the present invention may be used as a medicine or functional food for preventing, alleviating, or treating arthritis (especially rheumatoid arthritis). Further, the active ingredient of the composition according to the present invention can be obtained by an enzyme reaction between a readily available substrate such as agar or agarose and DagA as a beta-agarase derived from Streptomyces coelicolor. Thus, it can be produced at a relatively low cost and can easily be ingested by anyone because it has no side effects.

Abstract: The present invention provides Streptomyces coelicolor strain A3(2)_M22-2C43 obtained by inducing a point mutation in the base sequence of the DagB gene in a wild-type Streptomyces coelicolor strain A3(2) by UV radiation. Since the Streptomyces coelicolor strain A3(2)_M22-2C43 according to the present invention expresses a DagB mutant enzyme expressing little or no DagB beta-agarase or exhibiting little or no beta-agarase activity, there is no need for separate isolation and purification of DagA enzymes from culture fluid, and the culture fluid of the Streptomyces coelicolor strain A3(2)_M22-2C43 or supernatant thereof may be used to produce, from agar or agarose, neoagarose oligosaccharides with a higher content of neoagarotetraose or neoagarohexaose than that of neoagarobiose.

Abstract: The present invention relates to a composition for prevention or treatment of sepsis or septic shock, in which the composition includes neoagarooligosaccharide as an active ingredient, and the neoagarooligosaccharide according to the present invention has an excellent effect in terms of immune enhancement by effectively suppressing inflammation, and also exhibits a good effect in preventing sepsis, and therefore can be effectively used in pharmaceuticals and functional foods for prevention or treatment of sepsis or septic shock and immune enhancement.

Abstract: Provided in the present invention is a composition having a novel use and containing a neoagarooligosaccharide mixture as an active ingredient. According to the present invention, a neoagarooligosaccharide mixture, which is the active ingredient of the composition according to the present invention, and the like can reduce the expression of RANKL, which is an osteoclast inducer, and effectively inhibit the differentiation of mononuclear cells into osteoclasts. Therefore, the composition according to the present invention can be used as a medicine or functional food for preventing, alleviating, or treating arthritis (especially rheumatoid arthritis) or osteoporosis.