Novel functionality of fermentation products obtained using Bifidobacterium bacteria and lactic acid bacteria was discovered, resulting in a bindability enhancer for collagen fibers in ligaments, tendons, cartilage, skin, periodontal tissue, and other such living tissues, the bindability enhancer having fermentation products of microorganisms selected from Bifidobacterium bacteria and/or lactic acid bacteria as active ingredients and being intended to provide a preparation for utilizing this functionality, as well as a method for repairing living tissues containing collagen, a method for preventing loss of strength of living tissues containing collagen, and a method for enhancing the strength of regenerated tissues using this bindability enhancer for collagen fibers.本發明係發現經使用雙歧桿菌屬細菌與乳酸菌之發酵生成物具有新穎的功能，並以提供利用該功能之製劑為目的，本發明係一種利用藉由選自雙歧桿菌屬細菌以及/或乳酸菌之微生物之發酵生成物為有效成分，作為韌帶、肌腱、軟骨、皮膚、牙周組織等生體組織等之膠原纖維的集束能增強劑，以及該軟骨纖維之集束能增強劑的含有膠原之生體組織的修復方法，本發明係含有膠原之生體組織的強度降低之預防方法以及再生組織的強度增強方法。
