Abstract: By contacting a peptide derivative or a protein having a property of binding to endotoxin (ET) to inhibit the activity of ET, and at least one surfactant with a sample containing ET, the activity of ET can be inhibited, and even when an ET analogous substance having ET activity is present in the thus treated sample, it can be measured without influence of ET.

Abstract: Microorganisms in a sample can be detected easily and rapidly with high precision by a process which comprises filtering the sample through a filter, washing the filter, reacting the residue on the filter with an insect hemolymph containing inactive type factors of the pro-phenol oxidase cascade, and detecting the microorganisms in the sample on the basis of the color change thus caused.

Abstract: A process for measuring the amount of endotoxin or (1.fwdarw.3)-.beta.-D-glucan (referred to hereinafter as .beta.-glucan) contained in a sample, which comprises mixing the sample with amebocyte lysate of horseshoe crabs in the presence of at least one water-soluble polymer selected from the group consisting of a polyethylene glycol, a polyvinyl alcohol, a methyl cellulose and a hydroxypropyl cellulose, applying a light to the resulting mixture, measuring the time required until a degree of optical variation of the resulting mixture reaches a predetermined value after the mixing of the sample with the amebocyte lysate, or after the lapse of the predetermined time from the mixing of the sample with the amebocyte lysate, and determining the amount of endotoxin or .beta.-glucan contained in the sample on the basis of the relationship between the said time and the amount of endotoxin or .beta.-glucan; and also a reagent for measuring the amount of endotoxin or .beta.

Abstract: By contacting a peptide derivative or a protein having a property of binding to endotoxin (ET) to inhibit the activity of ET, and at least one surfactant with a sample containing ET, the activity of ET can be inhibited, and even when an ET analogous substance having ET activity is present in the thus treated sample, it can be measured without influence of ET.

Abstract: By contacting a peptide derivative or a protein having a property of binding to endotoxin (ET) to inhibit the activity of ET, and at least one surfactant with a sample containing ET, the activity of ET can be inhibited, and even when an ET analogous substance having ET activity is present in the thus treated sample, it can be measured without influence of ET.

Abstract: A method for assaying an activity of a prophenoloxidase activating enzyme (PPAE), comprising assaying at least X-Arg or Y produced upon contact of the PPAE with a peptide chain of the formulaX-Arg-Ywherein X is an optionally labeled amino acid residue or peptide residue, having an optionally protected .alpha.-amino group or N-terminal, provided that the amino acid residue adjoining Arg is not Gly or Ala, and Y is an organic residue capable of binding to a carboxyl group of Arg by acid amide bonding or ester bonding, or an optionally labeled amino acid residue or peptide residue, having an optionally protected .alpha.-carboxyl group or C-terminal, the peptide chain capable of being hydrolyzed into X-Arg and Y by a PPAE derived from an insect. According to the present invention, PPAE activity can be quantitatively assayed with precision and a highly precise method for determining .beta.-1,3-glucan and/or peptidoglycan, wherein said PPAE activity is used as an index, can be provided.

Abstract: A pretreating method for a sample such as plasma for endotoxin measurement which includes diluting the sample with a surfactant-containing aqueous solution, and subjecting the diluted sample to heat treatment can prevent influences of inhibitors, etc. present in the sample and gives high recovery of endotoxins.

Abstract: A solution containing at least one of albumin and globulin is effective for extracting endotoxin adhered to or adsorbed on a surface of a solid such as containers, medical devices, disposable needles, etc., and thus useful as a cleaning agent for these containers, medical devices, etc.

Abstract: Measuring of endotoxin using a reaction of a horseshoe crab hemocyte lysate with endotoxin in a solution can be carried out in the presence of a water-soluble polysaccharide containing .beta.-1,3-glucosidic linkage and/or a water-soluble polysaccharide derivative containing .beta.-1,3-glucosidic linkage.

Abstract: Measuring of endotoxin using a reaction of a horseshoe crab hemocyte lysate with endotoxin in a solution can be carried out in the presence of a water-soluble polysaccharide containing .beta.-1,3-glucosidic linkage and/or a water-soluble polysaccharide derivative containing .beta.-1,3-glucosidic linkage.

Abstract: A reagent obtained by bringing an extracted solution of horseshoe crab hemocyte lysate into temporary contact with a treating agent such as a water-insoluble polysaccharide containing .beta.-1,3-glucosidic linkage and freeing the extracted solution from said treating agent is effective for specifically measuring endotoxin.

Abstract: A reagent comprising a fraction obtained from plasma of an insect such as silkworm larvae and capable of reacting specifically with .beta.-1,3-glucan or peptidoglycan can be used for determining .beta.-1,3-glucan or peptidoglycan.