樟芝(Antrodia camphorata)是台灣發現的特有物種，已知它是一種藥用菇類，廣泛應用於傳統中藥上。它的生理活性物質尚在分析中，目前已知主要的有效成分為多醣體及三萜類。本研究的目的在探討以樟芝菌絲體深層培養所獲得的胞外多醣體，應用於抑制3T3纖維母細胞所分泌基質金屬蛋白酶(matrix metalloproteinases, MMP)的活性；經由gelatin-based zymography進行 MMP-2及MMP-9的活性分析，我們發現樟芝胞外多醣體於0.5 mg/ml的處理劑量下，可以抑制MMP-2及MMP-9的活性，於48小時最為顯著。另一方面，利用不同的酒精濃度沉澱樟芝胞外多醣體，經由膠體過濾層析法(gel permeation chromatography)分析，證實不同的酒精濃度可分離得到不同分子量的多醣體；這些不同分子量的多醣體中，以33% 酒精濃度沉澱分離的多醣體抑制MMP-9的活性最顯著，而50~75% 沉澱酒精濃度所分離的多醣體抑制MMP-2活性的效果最佳。令人驚訝的是50~75%酒精濃度沉澱所得到的多醣體，於0.5 mg/ml的劑量，處理纖維母細胞4~8小時，在與控制組比較之下，發現膠原蛋白的累積量可增加38%。因此，我們認為樟芝胞外多醣體可應用於抗老化化妝品的成份。 Antrodia camphorata, an endemic species in Taiwan, is known as a medicinal mushroom and currently used as a traditional Chinese medicine. The constituent and bioactivity of A. camphorata is still in the analysis. For the present it is well known that polysaccharides and triterpenoids are major effective components in this medicinal fungus. The purpose of this study was to investigate the capacities of exopolysaccharides extracted from mycelium culture of A. camphorata in inhibiting the activities of matrix metalloproteinases (MMPs) secreted from fibroblasts. The analyses of gelatin-based zymography reveal that A. camphorata exopolysaccharides do suppress the activities of MMP-2 (gelatinase A, EC 3.4.24.24) and MMP-9 (gelatinase B, EC 3.4.24.35) at the treated concentration of 0.5 mg/ml. On the other hand, we undertook various concentrations of ethanol precipitation with A. camphorata exopolysaccharides to obtain several fractions of polysaccharides with different molecular weights determined by gel permeation chromatography. The different fractions of polysaccharides were also applied to evaluate the inhibitory ability on the activities of MMP-2 and MMP-9. The results presented here show that 33% ethanol-precipitated exopolysaccharides exhibit the markedly repressive ability on the activity of MMP-9, whereas 50~75% ethanol-precipitated exopolysaccharides significantly inhibit MMP-2 activity. Surprisingly, we also found that 50~75% ethanol-precipitated exopolysaccharides could give rise to collagen accumulation by 38% in the culture medium of fibroblasts when concentration was set at 0.5 mg/ml. Therefore, we suggest that exopolysaccharides from A. camphorata may show the antiaging capacities and will be an effective ingredient for utilization in antiaging cosmetic formulations.
