ISO 23753-1:2019 土壌の質 — 土壌中のデヒドロゲナーゼ活性の測定 — Part 1: トリフェニルテトラゾリウムクロライド（TTC）を使用する方法 | ページ 2

Foreword

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This document was prepared by Technical Committee ISO/TC 190, Soil quality, Subcommittee SC 4, Biological characterization.

This second edition cancels and replaces the first edition (ISO 23753-1:2005), which has been technically revised. The main changes compared to the previous edition are as follows:

• a new Clause 5 “Limitations” has been added;
• Clause 6, reagents and their preparation have been updated to new results [e.g. use of less toxic solvent (ethanol), substrate concentration of 60 mmol/l of TTC, concentration of Tris buffer of 100 mmol/l at pH 7,6, incubation time of 6 h];
• Tables 1 and 2 have been added;
• Clause 10"Validity criteria" has been added;
• a new Annex A “Results of modified parameters” has been added;
• Clause 2 “Normative references” and the Bibliography have been updated.

A list of all the parts in the ISO 23753 series can be found on the ISO website.

Introduction

The soil microflora is responsible for the decomposition and conversion of organic substances, carbon, nitrogen, sulfur and phosphorus cycles, soil aggregates stability and as a food source for microbivores. Dehydrogenases, as intracellular enzymes and respiratory chain components of the microbial cells, play a major role in the production of energy by organisms. They oxidize organic compounds by transferring electrons to an acceptor (e.g. NAD⁺). Dehydrogenases are essential components of the enzyme system of microorganisms. Dehydrogenases activity can therefore be used as an indicator of biological redox systems and as a measure of the viable and physiologically active soil microbial community.

Microbial oxidative activity in soil is linked to respiratory activity, which could be approached with the determination of dehydrogenases activity. Basal and induced respiration in soil could be affected by soil management, practices and contamination.

1 Scope

This document specifies a method for determining the activity of dehydrogenases enzymes in soil using 2,3,5-triphenyltetrazolium chloride (TTC).

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

3 Terms and definitions

No terms and definitions are listed in this document.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

Bibliography