- 背景資料
植酸(phytic acid)又稱肌醇六磷酸，主要存在於植物組織當中，在植物體中具有儲存磷酸與礦物質陽離子之功用。植酸為熱不敏感型抗營養因子的一種，不容易因加熱而受到破壞，因人類、豬、雞、魚...等生物，腸道中缺乏植酸酶(反芻動物除外，瘤胃的微生物可產生植酸酶)，而無法將植酸分解，因而使植酸與陽離子、澱粉/蛋白質形成難消化之複合物，進而使營養物質之消化或吸收速率下降。
➡️植酸被植酸酶(phytase)分解後，其產物可能為肌醇(inositol)、肌醇磷酸(inositol phosphate)、無機磷(Pi)
- STANDARD ASSAY PROCEDURE:
A. SAMPLE EXTRACTION:
1. Accurately weigh approx. 1 g of sample material into a 75 mL glass beaker. Add 20 mL of hydrochloric acid (0.66 M), cover the beaker with foil and stir vigorously for a minimum of 3 h at room temperature (preferably overnight for convenience).
2. Transfer 1 mL of extract to a 1.5 mL microfuge tube and centrifuge at 13,000 rpm for 10 min. Immediately transfer 0.5 mL of the resulting extract supernatant to a fresh 1.5 mL microfuge tube and neutralise by addition of 0.5 mL of sodium hydroxide solution (0.75 M). Use the neutralised sample extract in the enzymatic dephosphorylation reaction procedure described below.
B. ENZYMATIC DEPHOSPHORYLATION REACTION:
C. COLOURIMETRIC DETERMINATION OF PHOSPHORUS: MANUAL FORMAT
NOTE: For each batch of samples that is applied to the colourimetric determination of phosphorus, a phosphorus calibration curve must be performed concurrently using the same batch of colour reagent (see section D below).
D. PREPARATION OF PHOSPHORUS CALIBRATION CURVE:
Prepare the standard phosphorus solutions as described in the table below and treat as samples for the colourimetric determination of phosphorus (see section C above). Stable for 1 week at 4°C.
商品特色
商品規格
- 商品規格 50 檢測反應
Bottle 1:
Buffer (25 mL, pH 5.5) and sodium azide (0.02% w/v) as a preservative.
Stable for > 2 years at 4°C.
Bottle 2:
Phytase suspension (1.2 mL).
Stable for > 2 years at 4°C.
Bottle 3:
Buffer (25 mL, pH 10.4), plus MgCl2, ZnSO4 and sodium azide (0.02% w/v) as a preservative.
Stable for > 2 years at 4°C.
Bottle 4:
Alkaline phosphatase suspension (1.2 mL).
Stable for > 2 years at 4°C.
Bottle 5:
Phosphorus standard solution (24 mL, 50 μg/mL) and sodium azide (0.02% w/v) as a preservative.
Stable for > 2 years at 4°C.
Bottle 6:
Oat flour control powder
(5 g; Phosphorus content,see bottle).
Stable for > 5 years at room temperature.
