{"product_id":"tyrosinase-enzyme-activity-tbp0090","title":"Tyrosinase, Enzyme Activity","description":"\u003cp\u003e\u003cspan style=\"font-size: 18px\"\u003e\u003cstrong\u003e\u003cu\u003eProduct Details\u003c\/u\u003e\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cu\u003eForm:\u003c\/u\u003e Freeze-dried\u003c\/p\u003e\n\u003cp\u003e\u003cu\u003eSolubility:\u003c\/u\u003e Soluble in distilled water or dilute buffer\u003c\/p\u003e\n\u003cp\u003e\u003cu\u003eStability:\u003c\/u\u003e -20° C; -4° F\u003c\/p\u003e\n\u003cp\u003e\u003cu\u003eActivity:\u003c\/u\u003e 700 U\/mg solid\u003c\/p\u003e\n\u003cp\u003e\u003cu\u003eProtein:\u003c\/u\u003e 95%\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 18px\"\u003e\u003cstrong\u003e\u003cu\u003eUnit Definition\u003c\/u\u003e\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eThat amount of enzyme which causes an increase in extinction at 280 nm of 0.001 per minute at pH 6.5 and 25¡C.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 18px\"\u003e\u003cstrong\u003e\u003cu\u003eAssay Method\u003c\/u\u003e\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eTyrosinase catalyzes the oxidation of tyrosine to O-quinone which results in an increase in the absorbance at 280 nm.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 18px\"\u003e\u003cstrong\u003e\u003cu\u003eApplications\u003c\/u\u003e\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eTyrosinase (polyphenol oxidase, catecholase) (EC 1.14.18.1) is a copper-containing oxidase which is widely distributed in plants, animals and man. It oxidizes tyrosine to the pigment melanin in mammals and causes the cut surfaces of many fruits and vegetables to darken (browning reactions). The enzyme from mushrooms has a molecular weight of 128,000. Hearing, et al, report the occurrence of four isozymes of tyrosinase in tissues of mice with malignant melanoma. This observation may have some clinical significance.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 18px\"\u003e\u003cstrong\u003e\u003cu\u003eReagents\u003c\/u\u003e\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003col\u003e\n\u003cli\u003e0.5 M Potassium phosphate buffer, pH 6.5.\u003c\/li\u003e\n\u003cli\u003e0.001 M L-Tyrosine (0.181 mg\/ml) in buffer.\u003c\/li\u003e\n\u003cli\u003eTyrosinase (enzyme) solution. Prepare in distilled water to yield a final concentration of 200-400 U\/ml. The enzyme solution must be prepared fresh immediately prior to assay.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 18px\"\u003e\u003cstrong\u003e\u003cu\u003eProcedure\u003c\/u\u003e\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003col\u003e\n\u003cli\u003eSet spectrophotometer (equipped with strip chart recorder and temperature control) at 25°C and 280 nm.\u003c\/li\u003e\n\u003cli\u003eInto a quartz cuvette, pipette the following:\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp style=\"padding-left: 40px\"\u003ePhosphate buffer 1.90 ml\u003c\/p\u003e\n\u003cp style=\"padding-left: 40px\"\u003eTyrosine 1.00 ml\u003c\/p\u003e\n\u003col start=\"3\"\u003e\n\u003cli\u003eOxygenate this reaction mixture by bubbling oxygen into the cuvette through a capillary tube for 5 minutes.\u003c\/li\u003e\n\u003cli\u003eTransfer cuvette to spectrophotometer and incubate for 5 minutes at 25°C to attain temperature equilibration. Record absorbance at 280 nm to establish the blank rate, if any.\u003c\/li\u003e\n\u003cli\u003eInitiate the reaction by adding 0.1 ml of tyrosinase solution (200-400 U\/ml) to the cuvette and record absorbance at 280 nm for 10 minutes.\u003c\/li\u003e\n\u003cli\u003eDetermine µE280nm\/min from the linear portion of the curve.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003e\u003c!--TBP0090-10KU TBP0090-50KU--\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 13px; font-weight: 700; text-transform: uppercase;\"\u003e\u003cstrong\u003eResearch use only.\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003eDocuments\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/tribioscience.com\/wp-content\/uploads\/2024\/03\/TBP0090-Tyrosinase-2.pdf\"\u003eDatasheet (PDF)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/tribioscience.com\/wp-content\/uploads\/2024\/03\/TBP0090_Tyrosinase-Safety-Data-Sheet-1.pdf\"\u003eMSDS (PDF)\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"TriBioScience","offers":[{"title":"10 KU","offer_id":45986501230671,"sku":"TBP0090-10KU","price":0.0,"currency_code":"ILS","in_stock":true},{"title":"50 KU","offer_id":45986501263439,"sku":"TBP0090-50KU","price":0.0,"currency_code":"ILS","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0712\/0748\/5519\/files\/TBP0090-10KU.jpg?v=1782812693","url":"https:\/\/www.danyel.co.il\/products\/tyrosinase-enzyme-activity-tbp0090","provider":"danyel biotech","version":"1.0","type":"link"}