Aims:  To determine the effect of environmental conditions on the production of extracellular lignocellulose‐degrading enzymes by Streptomyces sp. F2621 and to assess the potential use of these enzymes in the hydrolysis of lignocellulose material. Methods and Results:  The production of extracellular lignocellulose‐degrading enzymes, endoxylanase, endoglucanase and peroxidase during the growth of Streptomyces sp. F2621 in basal salts‐yeast extract medium containing different carbon sources and the effect of a number of environmental parameters (e.g. carbon sources and concentrations, pH and temperature) were investigated. The highest endoxylanase (22·41 U ml−1) and peroxidase (0·58 U ml−1) activities were obtained after 2–4 days of incubation at 30°C in a basal salts medium containing 0·4% (w/v) oat spelt xylan and 0·6% (w/v) yeast extract, corresponding to C : N ratio of 6 : 1. Cell‐free extracellular enzyme preparations from the strain were capable of releasing both sugar and aromatic compounds during incubation with eucalyptus paper pulp, straw and xylan. Overall, 9·3% hydrolysis of xylan occurred after 24‐h incubation. However the rates of hydrolysis of paper pulp and straw were approximately twofold less than xylan hydrolysis, although the total percentage hydrolysis of available substrate (24·5% and 16·3%, respectively) was greater than xylan hydrolysis. Conclusions:  The high levels of enzyme production achieved under batch cultivation conditions, coupled with no significant production of endoglucanase during the growth phase of organism and the release of both sugar and aromatic compounds from paper pulp and straw signify the suitability for these enzymes for industrial applications such as pulp and paper production. Significance and Impact of the Study:  The results highlight the environmental conditions for the production of extracellular lignocellulose‐degrading enzymes by Streptomyces sp. F2621 and suggest the use of streptomycetes and/or their enzymes in industrial processes.

-Streptomyces sp. F6616 was found to produce higher levels of extracellular peroxidase activity (0.535 U/ mL) without any inducers than other actinobacteria which are previously reported. Maximum specific peroxidase activity (6.21 U/mg of protein) was obtained after 72 h of incubation at 30 °C in a minimal salt medium (pH 8.0) containing (in wt/v) 0.6% yeast extract and 0.8% ball-milled wheat straw corresponding to a C:N ratio of 4.6:1. Characterization of the peroxidase revealed that the optimal temperature for the enzyme activity, using the standard 2,4-dichlorophenol (2,4-DCP) assay was 50 °C, when the enzyme reaction was performed at pH 8.0. A study of the effect of temperature on the stability of peroxidase over time, showed that the enzyme was stable at 50 °C, with a half-life of 145 min, while at higher temperature the stability and activity was reduced such that at 60 °C the half-life of the enzyme was 30 min. The optimum pH for the activity of the enzyme occurred between pH 9.0 and 10.0. The apparent K m and V max values for the peroxidase preparations were determined to be 1.52 mmol/L and 1.84 U/mg protein, respectively using 2,4-DCP as a substrate. Characterization of the peroxidase activity revealed activity against 2,4-DCP, L-3,4-dihydroxyphenylalanine (L-DOPA), 2,4,5-trichlorophenol and other chlorophenols in the presence of hydrogen peroxide. However, inhibition of peroxidase activity with the addition of potassium cyanide and sodium azide, suggested the presence of heme component in the tertiary structure of the enzyme.