Changes of Some Organic Acids in the Hydrolysates of Decomposing Litters of Wild Grasses and Tree Leaves

부숙과정중(腐熟過程中) 낙엽류(落葉類) 가수분해물(加水分解物)의 유기산함량(有機酸含量) 변화(變化)

Changes in the concentrations of six low-molecular-weight organic acids extracted from hydrolysates of plant residues undergoing decomposition for 90 days under the laboratory condition were investigated. 1. Litters of deciduous and coniferous trees and wild grass cuttings were sampled for the study and concentrations of formic, acetic, succinic, tartaric, malic and citric acids were determined. The concentration of malic acid were negligible. 2. In the wild grass cuttings, the total concentration of low-molecular-weight organic acids decreased with the passage of decomposition. Monocarboxylic acids, I. e., formic and acetic acids, predominated over dicarboxylic and tricarboxylic acids. Formic and acetic acids appeared to be compensatory for each other. Concentration of citric acid increased at a remarkable rate. 3. The total concentration of organic acids in the hydrolysates of deciduous litter was shown to increase. The concentration of monocarboxylic acids was significantly higher in the end of the period of decomposition. Here again a compensatory relationship was observed between concentrations of formic and acetic acids. 4. There was comparatively little change exhibited during the period of experiment concerning the concentrations of organic acids from hydrolysates of decomposing coniferous litter. In contrast with the others, however, the concentration of succinic acid, a dicarboxylic acid, maintained the highest level.

산야초(山野草), 활엽수(闊葉樹)와 침엽수낙엽(針葉樹落葉)을 실험실조건하(實驗室條件下)에서 90일간(日間) 부숙(腐熟)시키면서 경시적(經時的)으로 시료(試料)를 채취(採取)하여 산가수분해(酸加水分解)시킨후 6개(個)의 저분자량(低分子量)의 유기산(有機酸)을 분석(分析)한 결과(結果)는 다음과 같다. 1. Formic, acetic, succinic, malic, tartaric와 citric acid가 검출(檢出)되었으며 이중(中) malic acid는 전시료중(全試料中)에서 극(極)히 미량(微量)으로 함유(含有)되어 있었다. 2. 산야초(山野草)의 경우 저분자량(低分子量) 유기산(有機酸)의 농도(濃度)는 부숙기간(腐熟期間)이 경과(經過)함에 따라 감소(減少)했으며 formic acid와 acetic acid등(等) monocarboxylic acid는 dicarboxylic acid와 tricarboxylic acid에 비(比)해 훨씬 높은 농도(濃度)를 보였고 formic acid와 acetic acid는 상호보충(相互補充) 관계(關係)가 있었다. Citric acid는 부숙기간(腐熟期間)이 경과(經過)함에 따라 농도(濃度)가 증가(增加)하였다. 3. 활엽수낙엽(闊葉樹落葉)의 경우 부숙기간(腐熟期間)이 경과(經過)함에 따라 monocarboxylic acid농도(濃度)가 상대적(相對的)으로 높았다. Formic acid와 acetic acid사이는 상호보충(相互補充) 관계(關係)가 있음이 구명(究明)되었다. 4. 침엽수낙엽(針葉樹落葉)의 경우 부숙기간(腐熟期間)이 경과(經過)함에 따라 유기함유량(有機含有量)의 변화(變化)가 별(別)로 나타나지 않았다. 산야초(山野草)와 활엽수낙엽(闊葉樹落葉)과는 대조적(對照的)으로 dicarboxylic acid인 succinic acid농도(濃度)가 가장 높았다.