| 摘要: | 本研究目的在探討產孢性乳酸菌－菊糖有孢子乳桿菌Sporolactobacillus inulinus BCRC 14647對模擬人體腸道中不良環境因子之抵抗性以及其在腸道中定殖與拮抗病原菌腸炎沙門氏菌Salmonella enteritidis BCRC 10744之能力，同時探討該菌株對人體腸道細胞之安全性，並與Lactobacillus acidophilus、L. bulgaricus、Bifidobacterium bifidum、B. longum等市售益生菌產品常添加之乳酸菌就上述試驗性質進行比較。酸與膽鹽耐受性，分別是以pH 2～4之酸液及0.1～0.4%之膽鹽溶液試驗之，而模擬腸道吸附性則是利用Caco-2 cells作為吸附試驗模式，另外抑菌試驗方面包含了乳酸菌培養基上清液抑制S. enteritidis生長之抑菌圈試驗以及上清液或其菌體拮抗S. enteritidis對模擬腸道細胞之吸附試驗。結果顯示在耐酸性方面，孢子形態的S. inulinus存活率顯著高於營養細胞形態的S. inulinus及Bifidobacterium spp. (p < 0.05)，而其中以Lactobacillus spp.的存活率最佳(p < 0.05)，此情形於耐膽鹽試驗中亦可看到類似的結果。而在模擬腸道細胞吸附試驗，則發現營養細胞形態的S. inulinus (65.1%)、L. bulgaricus (78.7%)和Bifidobacterium spp. (74.9%, 52.7%)皆具有良好的吸附性，其中以L. acidophilus對Caco-2 cells呈現出強力的吸附性(92.3%)，而孢子形態的S. inulinus則是低吸附性的(10.5%)。另外在抑菌圈之抑菌試驗方面，發現S. inulinus的培養基上清液可顯著地抑制S. enteritidis的生長，且其營養細胞或上清液亦具有干擾S. enteritidis吸附於模擬腸道細胞的能力，同時預先以S. inulinus吸附於模擬腸道細胞亦可預防S. enteritidis的吸附。此外，侵入性試驗也顯示了S. inulinus具有高度的安全性。本研究顯示，營養細胞形態之S. inulinus因能夠吸附於模擬人類腸道細胞並拮抗腸炎沙門氏菌而具有潛在之益生功效。
The basic characteristics of the spore-forming lactic acid bacterium (SFLAB), Sporolactobacillus inulinus BCRC 14647, associated with its potential probiotic effects were evaluated in vitro. Assessments including acid and bile salt tolerance, adhesiveness, and antagonistic effects on pathogenic Salmonella enteritidis BCRC 10744, and an invasion assay were conducted using lactic acid bacteria (LAB) Lactobacillus spp. (Lactobacillus acidophilus BCRC 10695, L. bulgaricus BCRC 14009) and Bifidobacterium spp. (Bifidobacterium bifidum BCRC 14615, B. longum BCRC 11847) as a reference. For the acid and bile tolerance test, the samples were treated with pH 2~4 acid solutions and 0.1~0.4% oxgall bile solutions, respectively. The adhesion test was conducted using Caco-2 cells as the assay model. For the antagonistic activity of LAB toward pathogen S. enteritidis, the well diffusion assay method was used, the inhibition effect of LAB cells or their spent culture supernatants (SCS) on the binding of the pathogen to the Caco-2 cells was explored. In the results, S. inulinus spores presented significant higher survival rates than the vegetative cell form in acidic conditions as well as than the reference Bifidobacterium spp. However, Lactobacillus spp. showed the highest viability among all tested strains. Similar results were found in the bile tolerance test. Compared to the reference strains, the vegetative cell form of S. inulinus possessed a proper adhesive characteristic (65.1% for S. inulinus, 78.7% for L. bulgaricus and 74.9% and 52.7% for B. bifidum and B. longum, respectively). In the adhesion assay, the spore form of S. inulinus displayed weak adhesive traits (10.5%). On the other hand, L. acidophilus showed a strong adhesive property (92.3%). The vegetative cells of S. inulinus and its SCS both dramatically reduced the adhesion of S. enteritidis to Caco-2 cells; meanwhile, the SCS of S. inulinus vegetative cells inhibited the growth of S. enteritidis in the inhibition zone test. From the results of the invasion assay, S. inulinus showed high safety properties. Based on the results of in vitro tests, S. inulinus shows the potential probiotic effects via the adherence to simulated human intestinal epithelial cells and the antagonistic activity against S. enteritidis. The vegetative cells of S. inulinus may be considered a candidate for the probiotic use. |
