{"id":26425,"date":"2025-11-05T16:54:02","date_gmt":"2025-11-05T09:54:02","guid":{"rendered":"https:\/\/nhathuocngocanh.com\/bp\/?p=26425"},"modified":"2025-11-05T16:54:02","modified_gmt":"2025-11-05T09:54:02","slug":"pepsin","status":"publish","type":"post","link":"https:\/\/nhathuocngocanh.com\/bp\/pepsin\/","title":{"rendered":"Pepsin"},"content":{"rendered":"

(Pepsin Powder, Ph. Eur. monograph 0682)<\/em><\/p>\n

9001-75-6<\/p>\n

Action and use<\/strong><\/p>\n

Proteolytic enzyme.<\/p>\n

DEFINITION<\/h2>\n

Powder prepared from the gastric mucosa of pigs, cattle or sheep. It contains gastric proteinases, active in acid medium (pH 1 to 5).<\/p>\n

Activity: Not less than 0.5 Ph. Eur. U.\/mg (dried substance).<\/p>\n

PRODUCTION<\/h2>\n

The animals from which pepsin powder is derived must fulfil the requirements for the health of animals suitable for human consumption.<\/p>\n

CHARACTERS<\/h2>\n

Appearance<\/h3>\n

White or slightly yellow, crystalline or amorphous powder, hygroscopic.<\/p>\n

Solubility<\/h3>\n

Soluble in water, practically insoluble in ethanol (96 per cent).
\nThe solution in water may be slightly opalescent with a weak acidic reaction.<\/p>\n

IDENTIFICATION<\/h2>\n

In a mortar, pound 30 mg of fibrin blue R. Suspend in 20 mL of dilute hydrochloric acid R2. Filter the suspension on a filter paper and wash with dilute hydrochloric acid R2 until a colourless filtrate is obtained. Perforate the filter paper and wash the fibrin blue R through it into a conical flask using 20 mL of dilute hydrochloric acid R2.<\/p>\n

Shake before use. Dissolve a quantity of the substance to be examined, equivalent to not less than 20 Ph. Eur. U., in 2 mL of dilute hydrochloric acid R2 and adjust to pH 1.6 \u00b1 0.1. Add 1 mL of this solution to a test-tube containing 4 mL of the fibrin blue suspension, mix and place in a water-bath at 25 \u00b0C with gentle shaking. Prepare a blank solution at the same time and in the same manner using 1 mL of water R. After 15 min of incubation the blank solution is colourless and the test solution is blue.<\/p>\n

TESTS<\/h2>\n

Loss on drying (2.2.32)<\/h3>\n

Maximum 5.0 per cent, determined on 0.500 g by drying at 60 \u00b0C over diphosphorus pentoxide R at a pressure not exceeding 670 Pa for 4 h.<\/p>\n

Microbial contamination<\/h3>\n

TAMC: acceptance criterion 104<\/sup> CFU\/g (2.6.12).<\/p>\n

TYMC: acceptance criterion 102<\/sup> CFU\/g (2.6.12).<\/p>\n

Absence of Escherichia coli (2.6.13).<\/p>\n

Absence of Salmonella (2.6.13).<\/p>\n

ASSAY<\/h2>\n

The activity of pepsin powder is determined by comparing the quantity of peptides, non-precipitable by trichloroacetic acid solution R and assayed using the phosphomolybdotungstic reagent R, which are released per minute from a substrate of haemoglobin solution R, with the quantity of such peptides released by pepsin powder BRP from the same substrate in the same conditions.<\/p>\n

For the test solution and the reference solution, prepare the solution and carry out the dilution at 0 \u00b0C to 4 \u00b0C.<\/p>\n

Avoid shaking and foaming during preparation of the test and reference solutions.<\/p>\n

Test solution: Immediately before use, prepare a solution of the substance to be examined expected to contain 0.5 Ph. Eur. U.\/mL in dilute hydrochloric acid R2; before dilution to volume, adjust to pH 1.6 \u00b1 0.1, if necessary, using 1 M hydrochloric acid.<\/p>\n

Reference solution: Less than 15 min before use, prepare a solution of pepsin powder BRP containing 0.5 Ph. Eur. U.\/mL in dilute hydrochloric acid R2; before dilution to volume, adjust to pH 1.6 \u00b1 0.1, if necessary, using 1 M hydrochloric acid.<\/p>\n

Table 0682.-1<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Tubes<\/strong><\/td>\n<\/tr>\n
<\/td>\nS1<\/sub><\/strong><\/td>\nS1b<\/sub><\/strong><\/td>\nS2<\/sub><\/strong><\/td>\nS2b<\/sub><\/strong><\/td>\nS3<\/sub><\/strong><\/td>\nS3b<\/sub><\/strong><\/td>\nT<\/strong><\/td>\nTb<\/sub><\/strong><\/td>\nB<\/strong><\/td>\n<\/tr>\n
Dilute hydrochloric acid R2 (mL)<\/td>\n0.5<\/td>\n0.5<\/td>\n0.25<\/td>\n0.25<\/td>\n<\/td>\n<\/td>\n0.25<\/td>\n0.25<\/td>\n1.0<\/td>\n<\/tr>\n
Reference solution (mL)<\/td>\n0.5<\/td>\n0.5<\/td>\n0.75<\/td>\n0.75<\/td>\n1.0<\/td>\n1.0<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/tr>\n
Test solution (mL)<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/td>\n0.75<\/td>\n0.75<\/td>\n<\/td>\n<\/tr>\n
Trichloroacetic acid solution R (mL)<\/td>\n<\/td>\n10.0<\/td>\n<\/td>\n10.0<\/td>\n<\/td>\n10.0<\/td>\n<\/td>\n10.0<\/td>\n10.0<\/td>\n<\/tr>\n
Mix<\/td>\n<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n+<\/td>\n<\/tr>\n
Water bath at 25 \u00b0C<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n<\/tr>\n
Haemoglobin solution R (mL)<\/td>\n<\/td>\n5.0<\/td>\n<\/td>\n5.0<\/td>\n<\/td>\n5.0<\/td>\n<\/td>\n5.0<\/td>\n5.0<\/td>\n<\/tr>\n
Mix<\/td>\n<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n+<\/td>\n<\/tr>\n
Haemoglobin solution R (mL)<\/td>\n5.0<\/td>\n<\/td>\n5.0<\/td>\n<\/td>\n5.0<\/td>\n<\/td>\n5.0<\/td>\n<\/td>\n<\/td>\n<\/tr>\n
Mix<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n<\/td>\n<\/td>\n<\/tr>\n
Water bath at 25 \u00b0C, 10 min<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n<\/tr>\n
Trichloroacetic acid solution R (mL)<\/td>\n10.0<\/td>\n<\/td>\n\u00a010.0<\/td>\n<\/td>\n\u00a010.0<\/td>\n<\/td>\n\u00a010.0<\/td>\n<\/td>\n<\/td>\n<\/tr>\n
Mix<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n<\/td>\n+<\/td>\n<\/td>\n<\/td>\n<\/tr>\n
Filter<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n+<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Designate tubes in duplicate T, Tb<\/sub>, S1<\/sub>, S1b<\/sub>, S2<\/sub>, S2b<\/sub>, S3<\/sub>, S3b<\/sub>; designate a tube B.<\/p>\n

Add dilute hydrochloric acid R2 to the tubes as follows:<\/p>\n

B: 1.0 mL<\/p>\n

S1<\/sub> and S1b<\/sub>: 0.5 mL<\/p>\n

S2<\/sub>, S2b<\/sub> and T and Tb<\/sub>: 0.25 mL<\/p>\n

Add the reference solution to the tubes as follows:<\/p>\n

S1<\/sub> and S1b<\/sub>: 0.5 mL<\/p>\n

S2<\/sub> and S2b<\/sub>: 0.75 mL<\/p>\n

S3<\/sub> and S3b<\/sub>: 1.0 mL<\/p>\n

Add 0.75 mL of the test solution to tubes T and Tb<\/sub>.<\/p>\n

Add 10.0 mL of trichloroacetic acid solution R to tubes S1b<\/sub>, S2b<\/sub>, S3b<\/sub>, Tb<\/sub> and B. Mix by shaking.<\/p>\n

Place the tubes and haemoglobin solution R in a water bath at 25 \u00b1 0.1 \u00b0C. When temperature equilibrium is reached, add 5.0 mL of haemoglobin solution R to tubes B, S1b<\/sub>, S2b<\/sub>, S3b<\/sub> and Tb<\/sub>. Mix.<\/p>\n

At time zero add 5.0 mL of haemoglobin solution R successively and at intervals of 30 s to tubes S1<\/sub>, S2<\/sub>, S3<\/sub> and T.<\/p>\n

Mix immediately after each addition.<\/p>\n

Exactly 10 min after adding the haemoglobin solution R, stop the reaction by adding, at intervals of 30 s, 10.0 mL of trichloroacetic acid solution R to tubes S1<\/sub>, S2<\/sub>, S3<\/sub> and T (the use of a fast-flowing or blow-out pipette is recommended) and mix.<\/p>\n

Filter the contents of each tube (samples and blanks) twice through the same suitable filter paper previously washed with a 50 g\/L solution of trichloroacetic acid R, then with water R and dried. Discard the first 5 mL of filtrate. Place 3.0 mL of each filtrate separately in a tube containing 20 mL of water R. Mix.<\/p>\n

A suitable filter paper complies with the following test Filter 5 mL of a 50 g\/L solution of trichloroacetic acid R through a 7 cm disc of white filter paper: the absorbance (2.2.25) of the filtrate, measured at 275 nm using unfiltered trichloroacetic acid R solution as the compensation liquid, is less than 0.04.<\/p>\n

Add to each tube 1.0 mL of sodium hydroxide solution R and 1.0 mL of phosphomolybdotungstic reagent R, beginning with the blanks and then the samples of each set, in a known order.<\/p>\n

A schematic presentation of the above operations is shown in Table 0682.-1.<\/p>\n

After 15 min measure the absorbance (2.2.25) of solutions S1<\/sub>, S2<\/sub>, S3<\/sub>, S1b<\/sub>, S2b<\/sub>, S3b<\/sub> and T at 540 nm using the filtrate obtained from tube B as the compensation liquid. Correct the average absorbance values for the filtrates obtained from tubes S1<\/sub>, S2<\/sub> and S3<\/sub> by subtracting the average values obtained for the filtrates from tubes S1b<\/sub>, S2b<\/sub>, S3b<\/sub> respectively. Draw a calibration curve of the corrected values against volume of reference solution used. Determine the activity of the substance to be examined using the corrected absorbance for the test solution (T – Tb) together with the calibration curve and taking into account the dilution factors.<\/p>\n

STORAGE<\/h2>\n

Store in an airtight container, protected from light, at a temperature of 2 \u00b0C to 8 \u00b0C.<\/p>\n

LABELLING<\/h2>\n

The label states the activity in European Pharmacopoeia Units per milligram.<\/p>\n","protected":false},"excerpt":{"rendered":"

(Pepsin Powder, Ph. Eur. monograph 0682) 9001-75-6 Action and use Proteolytic enzyme. DEFINITION Powder prepared from the gastric mucosa of pigs, cattle or sheep. It contains gastric proteinases, active in acid medium (pH 1 to 5). Activity: Not less than 0.5 Ph. Eur. U.\/mg (dried substance). PRODUCTION The animals from which pepsin powder is derived…<\/p>\n","protected":false},"author":4,"featured_media":26468,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-26425","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-medicinal-substances"],"acf":[],"_links":{"self":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26425","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/comments?post=26425"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26425\/revisions"}],"predecessor-version":[{"id":26472,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26425\/revisions\/26472"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/26468"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=26425"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=26425"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=26425"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}