Intraluminal digestion

…Of the three major nutrients, the digestion of carbohydrates and proteins is somewhat different from the digestion of lipids. The digestion of the former can be broadly divided into two stages: intermediate digestion in the tract (intraluminal digestion) and terminal digestion by small intestinal cells. Intraluminal digestion is carried out by the action of digestive enzymes contained in the digestive juices, which mix with food secreted by the body. This process is also called intraluminal digestion, but rather than producing low molecular weight substances that can be absorbed directly from high molecular weight substances all at once, it breaks the bonds inside the polymers, gradually breaking them down into smaller molecules, and digests them to the stage just before they become absorbable low molecular weight substances. …

*Some of the terminology that refers to "intral digestion" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…三大栄養素のうち，炭水化物およびタンパク質の消化と，脂質の消化にはやや異なった様相がみられる。前者の消化は管内の中間消化(管腔内消化)と小腸細胞による終末消化の二つの段階に大別できる。管腔内消化は，食物が分泌された消化液と混和し，消化液中に含まれている消化酵素の作用で行われる消化で，管内消化ともよばれるが，この過程は高分子物質から一挙に直接吸収しうる低分子物質を産生するのではなく，高分子内部の結合を切断して逐次分子を細かくし，吸収しうる低分子の一歩手前の段階までの消化をうけもつものである。…

※「管腔内消化」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報