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The present study was carried in the Department of Soil Science and Agricultural Chemistry, College of Agriculture, Rajendranagar. The humic and fulvic acids were extracted, isolated and purified from manures and characterise the physico – chemical properties of humic fractions. It has been found that the total acidity in humic acids of farmyard manure and vermicompost was 8.3 and 7.3 respectively, carboxylic groups 5.08 and 3.44 and phenolic- OH groups 3.05 and 3.86 while that of fulvic acids were 9.61 and 8.7, 6.4 and 5.1 and 3.21 and 3.6 me g-1 respectively. Among the humic fractions fulvic acid had higher total acidity, carboxylic and phenolic-OH groups than the corresponding humic acid obtained from farmyard manure and vermicompost. The ratio of optical densities at 465 and 665 nm i.e. E4/E6 ratio was higher in case of fulvic acids are ranging 8.4 and 6.2 and humic acids were narrow ranging 4.9 and 4.4, respectively.

Key words: Farmyard manure (FYM), Vermicompost (VC), Humic acid (HA), Fulvic acid (FA), total acidity, carboxyl groups, E4/E6 ratio and UV-Spectra.