Metabolisme KarbohidratFungsi utama

Metabolisme Karbohidrat
Fungsi utama dari metabolisme karbohidrat adalah menghasilkan energy dalam bentuk senyawa yang mengandung ikatan fosfat bertenaga tinggi.
Pencernaan Karbohidrat
Karbohidrat tersimpan dalam bentuk pati, glikogen, sukrosa, dan laktosa. Karbohidrat dicerna melalui cara hidrolisis ikatan glikosida untuk membebaskan oligosakarida, disakarida, dan monosakarida. Pencernaan karbohidrat dimulai dari mulut yang memiliki α-amilase dari kalenjar saliva. Enzim α-amilase termasuk endosakaridase, menghidrolisis polisakarida pada ikatan α- 1,4 glikosidik. Utamanya perncernaan karbohidrat terjadi pada usus kecil. Enzim amylase disekresi pancreas membutuhkan ion cl¯ dan ph optimum 7 untuk menghidrolisis amilosa menjadi maltosa dan glukosa. Amilopektin dan glikogen juga dihidrolisis menjadi glukosa, maltosa, maltotriosa dan oligosakaridase. Hasil utama hidrolisis disakarida adalah glukosa, galaktosa, dan fruktosa. Monosakarida diserap masuk ke dalam vena porta setelah melewati hepar untuk diedarkan ke seluruh tubuh.
Glukosa, galaktosa, dan fruktosa masuk ke dalam sel melalui dua mekanisme, yaitu:
1. Absorpsi glukosa dan galaktosa melalui sistem kotranspor Naᶧ monosakarida yang dikhususkan untuk D-glukosa dan D-galaktosa, yang akan dibawa oleh protein transportasi (SGLT1) ke dalam sel, kemudian bergabung dengan pompa Naᶧ, Kᶧ sehingga aktif melawan gradient konsentrasi. Glukosa dialirkan secara pasif karena konsentrasi glukosa intraseluler lebih tinggi dalam darah.
2. Absorpsi fruktosa melalui sistem difusi dan tidak bergantung Naᶧ, akan dibawa oleh protein transportasi (GLUT5) kemudian diserap secara difusi dengan penyerapan melalui gradient konsentrasi yang rendah. Fruktosa dan gula alcohol akan tetap berada dalam lumen usus. Tetapi D-fruktosa akan mengalami difusi pasif untuk meninggalkan usus.

Metabolisme dikategorikan menjadi dua yaitu, anabolisme dan katabolisme. Anabolisme adalah proses yang membuat molekul sederhana menjadi molekul yang lebih kompleks. Proses ini termasuk reaksi endothermic karena membutuhkan energy. Sedangkan, katabolisme merupakan proses pemecahan molekul yang kompleks menjadi molekul yang lebih sederhana. Proses ini termasuk reaksi esothermik karena mengeluarkan energy.
Pembagian metabolism karbohidrat sebagai berikut:
1. Glikolisis
2. Oksidasi asam piruvat
3. Glukoneogenesis
4. Glikogen
5. Jalur alternative metabolism karbohidrat

Glikolisis
Glikolisis adalah proses reaksi yang memecah 1 mlekul glukosa menjadi 2 molekul asam piruvat dan 2 molekul asam laktat. Proses ini bisa terjadi dalam suasana aerobic dan anaerobic. Glikolisis aerobic menghasilkan energy 7 mol ATP. Glikolisis anaerobic menghasilkan energy 2 mol ATP.
Jalur glikolisis ada 3 tahap :
1. Tahap pertama melibatkan penggunaan 2 molekul ATP
D-glukosa + 2 ATP⁴¯ → D-fruktosa 1,6 bifosfat⁴¯ + 2 ADP³¯ + 2Hᶧ
2. Tahap kedua adalah perubahan heksosa (C6) menjadi triosa (C3)
D-fruktosa 1,6 bifosfat⁴¯→2 D-gliseraldehida 3 fosfat²¯
3. Tahap ketiga adalah fosforilasi oksidoreduktase. Tiap molekul heksosa menghasilkan 4 molekul ATP.
Oksidasi Asam Piruvat
Asam piruvat hasil glikolisis akan akan masuk ke dalam mitokondria dan akan mengalami oksidasi-dekarboksilasi oleh piruvat dehidrogenase kompleks. Enzim kompleks ini terdiri dari 3 enzim dan 5 koenzim. Reaksi ini adalah reaksi irreversible. Hasil oksidasi 1 mol piruvat adalah 1 mol asetil KoA dan NADH.
Glukoneogenesis
Glukoneogenesis merupakan mekanisme pembentukan glukosa baru saat diet karbohidrat tidak mencukupi, sehingga bukan berasal dari karbohidrat. Jalur glukoneogenesis terjadi di hepar dan ginjal. Jalur ini dicapai dengan 4 enzim kunci yaitu piruvat kinase, piruvat karboksilase, fosfofruktokinase, dan F 1,6 BP ase dan glukinase serta G6-P ase. Substrat glukoneogenesis adalah asam laktat, asam amino, gliserol, fruktosa, dan asam propianat.
Glikogen
Glikogen merupakan bentuk cadangan utama dari glukosa. Glikogen banyak terdapat di hati dan otot. Sintesis glikogen melalui jalur glikogenesis sedangkan pemecahan glikogen melalui jalur glikogenolisis. Glikogen dalam hati digunakan untuk menyediakan glukosa untuk jaringan ekstraheatk. Glikogen dalam otot digunakan sebagai sumber bahan bakar metabolic.
Jalur alternative metabolisme karbohidrat
Jalur alternative ini melalui:
1. Jalur pentose fosfat
2. Jalur asam uronat
3. Metabolism fruktosa
4. Metabolism laktosa
5. Biosintesis gula amino.

Hasil (Inggris) 1:

Carbohydrate MetabolismThe main function of carbohydrate metabolism are generating energy in the form of compounds containing phosphate bonds high-powered.Digestion Of CarbohydratesCarbohydrates stored in the form of glycogen, starch, sucrose, and lactose. Carbohydrate is digested through the hydrolysis of Glycoside bonds to free oligosakarida, disaccharides, and monosaccharide. Carbohydrate digestion begins from the mouth that have α-amylase of saliva kalenjar. Α-amylase enzyme include the endosakaridase, the hydrolysis of polysaccharides on bonds of α-1,4 glycosidic linkage. The main perncernaan of carbohydrates occurred in the small intestine. The enzyme amylase secreted the pancreas needs cl ¯ ions and ph optimum for hydrolysis of amylose 7 into maltose and glucose. Amylopectin and glycogen also hydrolysed into glucose, maltose, maltotriosa and oligosakaridase. The main products of the hydrolysis of disaccharides are glucose, Galactose, and fructose. Monosaccharides absorbed into venous port after passing hepar for circulated throughout the body.Glucose, Galactose, and fructose goes into the cells via two mechanisms, namely:1. Absorption of glucose and galactose via the system kotranspor Na ᶧ monosaccharide that is devoted to D-glucose and D-galactose, which will be carried by transport proteins (SGLT1) into a cell, then joined ᶧ Na, K pump ᶧ so active against concentration gradient. Glucose streamed passively due to intracellular glucose concentration was higher in the blood.2. fructose Absorption through the diffusion system and not dependent Na ᶧ, will be carried by transport proteins (GLUT5) is then absorbed in the diffusion with absorption of low concentration gradient through. Fructose and sugar alcohol will remain in the intestinal lumen. But D-fructose will go through passive diffusion to leave the intestines.Categorized into two metabolism, anabolism and catabolism. Anabolism is the process that makes simple molecules into more complex molecules. This process is endothermic reactions including because it requires energy. Whereas, catabolism is the process of solving complex molecules into simpler molecules. This process includes the reaction of esothermik due to removing energy.Division of metabolism of carbohydrates as follows:1. Glycolysis2. Oxidation of pyruvic acid3. Gluconeogenesis4. Glycogen5. Line alternative metabolism of carbohydratesGlycolysisGlycolysis is the process reactions that break down the glucose mlekul 1 into 2 molecules of pyruvic acid and two molecules of lactic acid. This process can take place in an atmosphere of aerobic and anaerobic. Aerobic Glycolysis produces energy 7 moles of ATP. Anaerobic Glycolysis yields 2 mol ATP energy.There are 3 stages of Glycolysis pathway:1. The first stage involves the use of 2 molecules of ATPD-glucose + 2 ATP ⁴ ¯ → D-fructose 1,6 bifosfat ⁴ ¯ + 2 ADP + ¯ ³ 2 h ᶧ2. The second stage is the change heksosa (C6) becomes triosa (C3) D-fructose 1,6 bifosfat ⁴ ¯ → 2 D gliseraldehida 3-phosphate ² ¯3. The third stage is the phosphorylation of Oxidoreductase. Each molecule of ATP molecules produces a heksosa 4.Oxidation Of Pyruvic AcidPyruvate Glycolysis results will be entered into the mitochondrion and undergo oxidation-decarboxylation by the pyruvate dehydrogenase complex. The enzyme complex consists of 3 enzymes and coenzymes 5. This reaction is the reaction of such. The results of the oxidation of 1 mole of Pyruvate is 1 mole of acetyl Coa and NADH.GluconeogenesisGluconeogenesis glucose formation mechanism is new when insufficient carbs diet, so it is not derived from carbohydrates. The path of gluconeogenesis occurs in the kidney and hepar. The line is achieved with 4 key enzyme pyruvate pyruvate kinase, namely karboksilase, fosfofruktokinase, and F 1.6 BP ase and glukinase as well as the G6-P ase. Substrate gluconeogenesis is lactic acid, amino acids, glycerol, fructose, and propianat acid.GlycogenGlycogen is the main backup form of glucose. There are lots of glycogen in the liver and muscles. Glycogen synthesis via the glikogenesis while the breakdown of glycogen is via the glikogenolisis. Glycogen in the liver is used to provide glucose for the network ekstraheatk. Glycogen in the muscles is used as a source of metabolic fuel.Line alternative carbohydrate metabolismThis alternative path through:pentose phosphate Pathway 1.2. The path of uronat acid3. fructose Metabolism4. Metabolism of lactose5. the amino sugar Biosynthesis.

Hasil (Inggris) 2:

Carbohydrate Metabolism
The main function of the metabolism of carbohydrates is to produce energy in the form of compounds containing phosphate bonds of high-powered.
Digestion Carbohydrates
Carbohydrates are stored in the form of starch, glycogen, sucrose, and lactose. Digestible carbohydrates by glycoside bond hydrolysis to liberate oligosaccharides, disaccharides, and monosaccharides. Digestion of carbohydrates starts from the mouth that has α-amylase of the salivary gland. Enzyme α-amylase including endosakaridase, hydrolyzing polysaccharides on α- 1,4 glycosidic bond. The main carbohydrate digestive occurs in the small intestine. Amylase enzyme secreted from the pancreas requires optimum ion Cl and pH 7 to hydrolyze amylose into maltose and glucose. Amylopectin and glycogen also hydrolyzed to glucose, maltose, maltotriosa and oligosakaridase. The main results of hydrolysis of the disaccharide is glucose, galactose and fructose. Monosaccharides are absorbed into the portal vein after passing through the liver to be circulated throughout the body.
Glucose, galactose and fructose into the cell by two mechanisms, namely:
1. Glucose and galactose absorption through the system kotranspor Naᶧ monosaccharide devoted to D-glucose and D-galactose, which will be carried by the transport protein (SGLT1) into the cell, then join the pump Naᶧ, Kᶧ so active against a concentration gradient. Glucose flows passively through higher intracellular concentration of glucose in the blood.
2. Fructose absorption through diffusion system and does not rely Naᶧ, will be carried by transport proteins (GLUT5) then absorbed by absorption through the diffusion gradient low concentrations. Fructose and sugar alcohol will remain in the intestinal lumen. But D-fructose will have to abandon the passive diffusion intestine. Metabolism categorized into two, namely, anabolism and catabolism. Anabolism is the process that makes the simple molecules into more complex molecules. This process includes endothermic reaction because it takes energy. Meanwhile, catabolism is the breakdown of complex molecules into simpler molecules. This process includes esothermik reaction by releasing energy. The division of metabolism of carbohydrates as follows: 1. Glycolysis 2. Pyruvic acid oxidation 3. Gluconeogenesis 4. Glycogen 5. Alternative pathways of carbohydrate metabolism Glycolysis Glycolysis is a process that breaks 1 mlekul reaction of glucose into two molecules of pyruvic acid and 2 molecules of lactic acid. This process can take place in an atmosphere of aerobic and anaerobic. Aerobic glycolysis produces 7 moles of ATP energy. Anaerobic glycolysis produces 2 moles of ATP energy. Line glycolysis there are 3 stages: 1. The first stage involves the use of two molecules of ATP D-glucose + 2 ATP⁴¯ → D-fructose 1,6 bifosfat⁴¯ + 2 ADP³¯ + 2Hᶧ 2. The second stage is the change hexose (C6) into triose (C3) D-fructose 1,6 bifosfat⁴¯ → 2 D-glyceraldehyde 3 fosfat²¯ 3. The third stage is the phosphorylation oxidoreductase. Each molecule hexose produces 4 molecules of ATP. Oxidation Acid Pyruvate pyruvic acid glycolysis results will be entered into the mitochondria and will undergo oxidation-decarboxylation by pyruvate dehydrogenase complex. This enzyme complex consists of three enzymes and five coenzymes. This reaction is irreversible reactions. Results 1 mol pyruvate oxidation is 1 mole of acetyl CoA and NADH. Gluconeogenesis Gluconeogenesis is a new glucose formation mechanism currently insufficient carbohydrate diet, so it is not derived from carbohydrates. Gluconeogenesis pathway occurs in the liver and kidneys. This path is achieved with four key enzyme is pyruvate kinase, pyruvate carboxylase, phosphofructokinase and F 1.6 BP ase and glukinase and G6-P ase. Gluconeogenesis substrate is lactic acid, amino acids, glycerol, fructose, and acid propianat. Glycogen Glycogen is the primary backup form of glucose. There are a lot of glycogen in the liver and muscles. Glycogen synthesis through glikogenesis while the breakdown of glycogen through glycogenolysis. Glycogen in the liver are used to provide glucose for ekstraheatk network. Glycogen in the muscles is used as a source of metabolic fuel. Track alternative carbohydrate metabolism Strip this alternative through: 1. Pentose phosphate pathway 2. Uronat acid pathway 3. Metabolism of fructose 4. Metabolism of lactose 5. Amino sugar biosynthesis.