改善腸胃道功能 腸道菌叢 (1) 人體腸道內約有一百兆的細菌 (10 13 ) 胃 :ph 低菌數 < 10 3 /g 小腸 :ph 逐漸升高, 菌數約可達 10 6-10 7 /ml 大腸 : 菌叢主要聚集處, 菌相複雜, 總數達 10 11-10 12 /g, 主要為厭氧菌 Bacteroides Bifidobacterium Eubacterium 1
腸道菌叢 (2) 腸道的菌叢於出生後就開始逐漸形成 兼性厭氧菌為主 隨後依個人生活習慣及健康因素而改變 ( 尤其是飲食習慣 ) 餵母乳之嬰兒 - 主要菌叢為雙歧桿菌 (Bifidobacteria) 餵食配方奶粉 - 菌相複雜, 除雙歧桿菌外有 bacteroides clostridia streptococci 斷奶食用一般食品後 - 菌叢與成人一般 腸道菌叢的作用 將小腸不能消化吸收的醣類加以發酵利用, 產生能量 纖維素 半纖維素 膠質 寡醣以及醣醇類 未被消化吸收之蛋白質及氨基酸可以供作腸內菌生長的基質 維護人體的健康 有益菌附著於腸壁細胞作為屏障 合成人體所需的維生素 (B K) 代謝外來有害物質 2
腸道菌叢與宿主之關係 什麼是 Probiotic 與 Prebiotic? Probiotic: 乳酸菌 雙叉桿菌等這些有益於腸道健康的菌類 其來源衍生自希臘語, 意思是 for life 能夠預防致病菌的腸道生長, 並能增進腸道內的消化與特殊營養素的吸收與代謝 Prebiotic: 腸道益菌所需要的某些特殊營養素 幫助益菌的生長, 如果寡糖和某些特殊的維生素礦物質等物質 3
益生菌 (probiotics) 定義 : 經由改善宿主腸道均衡而有助於宿主的活性補充物 乳酸桿菌 (lactobacilli) 雙歧桿菌 (bifidobacteria) 及鏈球菌屬 (Streptococcus) 功能 : 改善菌叢促進腸道菌群安定 改善乳糖不耐症 : 產生 β 半乳糖甘酵素 增強免疫能力 : 刺激細胞激素 γ- 干擾素 降低血中膽固醇含量 降低有害物質 : 突變物質及細菌毒素 母親攝取益生菌似乎能提高其母乳中抗發炎分子的濃度, 因而可能為嬰兒帶來較佳的抗過敏能力與預防其他疾病的侵襲 Sweden s Karolinska Institute - 補充益生菌母親分娩後兩天母乳的成分後, 發現 cytokine( 細胞訊息傳遞物質 ) ---IL-10 的濃度增加 4
俄羅斯諾貝爾生理及醫學獎得主 細菌學家梅可尼可夫 (Elie Metchnikoff), 於 1908 年提出發酵牛乳中的某些乳酸菌能抑制腸道內的有害細菌 促進人類的健康和長壽的研究報告後, 也使得益生菌的重要性漸受重視 腸道有益菌 嗜乳酸桿菌 保加利亞乳酸桿菌 雙岐雙叉桿菌 龍根菌 嗜熱性鏈球菌等 食品的應用型式, 益生菌中約有 70% 被應用在乳品中, 包括發酵乳 乳酸菌飲料 乳酪 乾酪 優酪乳 酸乳 冷凍優格 牛乳 乳飲料等 5
益生菌之特性 源自於人體之有益菌 對酸與膽鹽耐受性強 公認安全的菌株 可定殖於腸道 成為優勢菌群 促進腸道健康 活性與穩定性高 能大量生產 益生菌的種類 Bifidobacterium Lactobacillus Lactococcus Saccharomyces Streptococcus thermophilus Enterococcus 6
Bifidobacterium-I Normal inhabitants of the human and animal colon. Newborns, especially those that are breast-fed, are colonized with bifidobacteria within days after birth. The population of these bacteria appears to be relatively stable until advanced age when it appears to decline. The bifidobacteria population is influenced by a number of factors, including diet, antibiotics and stress. Gram-positive anaerobes. They are non-motile, non-spore forming and catalase-negative. Derived from the observation that they often exist in a Y- shaped. Produce acetic and lactic acids without generation of CO 2, except during degradation of gluconate( 葡萄糖酸鹽 ). Classified as lactic acid bacteria (LAB). Bifidobacterium-II To date, 30 species of bifidobacteria have been isolated. Bifidobacteria used as probiotics include Bifidobacterium adolescentis, Bifidobacterium bifidum, Bifidobacterium animalis, Bifidobacterium thermophilum, Bifidobacterium breve, Bifidobacterium longum, Bifidobacterium infantis and Bifidobacterium lactis. Specific strains of bifidobacteria used as probiotics include Bifidobacterium breve strain Yakult, Bifidobacterium breve RO7O, Bifidobacterium lactis Bb12, Bifidobacterium longum RO23, Bifidobacterium bifidum RO71, Bifidobacterium infantis RO33, Bifidobacterium longum BB536 and Bifidobacterium longum SBT-2928. 7
Lactobacillus-I normal inhabitants of the human intestine and vagina. Gram-positive facultative anaerobes( 兼性厭氧菌為主 ). non-spore forming and non-flagellated rod or coccobacilli. either aerotolerant or anaerobic and strictly fermentative. classified as lactic acid bacteria (LAB). Lactobacillus-II To date, 56 species of the genus Lactobacillus have been identified. Lactobacilli used as probiotics include Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus bulgaricus, Lactobacillus casei, Lactobacillus cellobiosus, Lactobacillus crispatus, Lactobacillus curvatus, Lactobacillus fermentum, Lactobacillus GG (Lactobacillus rhamnosus or Lactobacillus casei subspecies rhamnosus), Lactobacillus gasseri, Lactobacillus johnsonii, Lactobacillus plantarum and Lactobacillus salivarus. Lactobacillus plantarum 299v strain originates from sour dough. Lactobacillus plantarum itself is of human origin. Other probiotic strains of Lactobacillus are Lactobacillus acidophilus BG2FO4, Lactobacillus acidophilus INT- 9, Lactobacillus plantarum ST31, Lactobacillus reuteri, Lactobacillus johnsonii LA1, Lactobacillus acidophilus NCFB 1748, Lactobacillus casei Shirota, Lactobacillus acidophilus NCFM, Lactobacillus acidophilus DDS-1, Lactobacillus delbrueckii subspecies delbrueckii, Lactobacillus delbrueckii subspecies bulgaricus type 2038, Lactobacillus acidophilus SBT-2062, Lactobacillus brevis, Lactobacillus salivarius UCC 118 and Lactobacillus paracasei subsp paracasei F19. 8
Lactococcus Gram-positive facultative anaerobes ( 兼性厭氧菌為主 ). Classified as lactic acid bacteria (LAB). Lactococcus lactis (formerly known as Streptococcus lactis) is found in dairy products and is commonly responsible for the souring of milk. Used or developed as probiotics include Lactococcus lactis, Lactococcus lactis subspecies cremoris (Streptococcus cremoris), Lactococcus lactis subspecies lactis NCDO 712, Lactococcus lactis subspecies lactis NIAI 527, Lactococcus lactis subspecies lactis NIAI 1061, Lactococcus lactis subspecies lactis biovar diacetylactis NIAI 8 W and Lactococcus lactis subspecies lactis biovar diacetylactis ATCC 13675. Saccharomyces Belongs to the yeast family. The principal probiotic yeast is Saccharomyces boulardii. Saccharomyces boulardii is also known as Saccharomyces cerevisiae Hansen CBS 5296 and S. boulardii. S. boulardii is normally a nonpathogenic yeast. S. boulardii has been used to treat diarrhea associated with antibiotic use. 9
Streptococcus thermophilus Gram-positive facultative anaerobe. It is a cytochrome-, oxidase- and catalase-negative organism that is nonmotile, non-spore forming and homofermentative. Streptococcus thermophilus is an alpha-hemolytic species of the viridans group. It is also classified as a lactic acid bacteria (LAB). Steptococcus thermophilus is found in milk and milk products. It is a probiotic and used in the production of yogurt. Streptococcus salivarus subspecies thermophilus type 1131 is another probiotic strain. Enterococcus Gram-positive, facultative anaerobic cocci of the Streptococcaceae family. Spherical to ovoid Non-spore forming and usually nonmotile. The intestinal microflora of humans and animals. Enterococcus faecium SF68 is a probiotic strain that has been used in the management of diarrheal illnesses. 10
腸道有害菌 E. coli Clostridia 為發酵氨基酸的菌株 產生毒素 侵入腸壁 活化致癌物質 腸內菌的醣代謝產物 氣體 :H 2 CO 2 CH 4 酸 : 醋酸 : 上皮細胞吸收, 運送至肌肉代謝產能 丙酸 : 降血低膽固醇的作用 ( 動物 ) 丁酸 : 腸上皮細胞主要能量的來源 11
免疫細胞 吞噬細胞 : 單核球 巨噬細胞 多形核嗜中性球 - 對抗感染第一線 淋巴細胞 B 細胞 : 分泌抗體 T 細胞 : 幫助 B 細胞分裂 分化及製造抗體 與單核吞噬細胞交互作用幫助消滅病源菌 破壞病毒或其他胞內病源感染的宿主細胞 自然殺手細胞 - 辨認並殺死腫瘤細胞 人體免疫力區分 非特異性免疫力 體表屏障 化學酵素 體液分泌系統 細胞巨噬作用以及血液中特殊蛋白質 特異性免疫力 藉由 B 與 T 淋巴細胞製造之抗體 有效因子 (effectors) 調節因子(regulators) 補體系統 (complement system) 12
免疫反應之區分 主動 (active) 免疫反應 可區分敵我細胞, 經由體液 ( 如血液 ) 與細胞防衛單位 ( 如白血球 ), 製造出特定之生化武器, 並透過循環系統運送至外來入侵因子場所 被動 (passive) 免疫反應 如施打疫苗 腸胃道免疫系統 (1) 黏膜免疫系統 經年累月接觸環境中的抗原, 演化出獨特的免疫構造與機制 - 有效區別病源菌與食物抗原 小腸是體內最多淋巴細胞的組織 10 6 個 /g 60% 的免疫球蛋白分泌於腸胃道中 IgA Ig D Ig E Ig G and Ig M 13
腸胃道免疫系統 (2) 上皮細胞層 : 抑制及毒殺的 CD8+ 型 T 細胞 固有層 : 輔助及誘導作用的 CD+4 型 T 細胞以及製造 Ig A 的 B 細胞 Peyer s Patch( 白氏囊淋巴結 ): 具有特殊不具纖毛構造的傳遞細胞 --M 細胞, 可輕易吞噬抗原及微生物 腸胃道免疫系統圖 白氏囊淋巴結 14
腸胃道免疫測定法 胃腸道功能改善之評估 促進消化吸收 消化酵素活性測定 : 雙醣酵素活性測定 改善胃腸道功能指標 : 脂肪之吸收判定 改善場內細菌菌相 有益菌 :Bifidobacterium 或 Lactobacillus 有害菌 :Clostridium perfringens 胃腸蠕動測試 15
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益生源 (Prebiotics) Such as inulin, short chain fructooligosaccharides (scfos) and oligofructose (the enzymatic hydrolysis product of inulin) They are vital to maintaining a healthy level of probiotic bacteria in the gut because they create a hospitable atmosphere for probiotic bacteria to grow and thrive. However, they are also known to impart other health benefits. 17
Prebiotics cannot be digested or absorbed by the body and thus pass through to the colon where they stimulate the growth and activity of friendly bacteria, as well as promote bowel regularity 18