Sulphonamides are biologically important compounds with low toxicity, many bioactivities and cost-effectiveness. Eight sulphonamide derivatives were synthesised and characterised by FT-IR, 13 C NMR, 1 H NMR, LC-MS and elemental analysis. Their inhibitory effect on AChE, and carbonic anhydrase I and II enzyme activities was investigated. Their antioxidant activity was determined using different bioanalytical assays such as radical scavenging tests with ABTS þ , and DPPH þ as well as metal-reducing abilities with CUPRAC, and FRAP assays. All compounds showed satisfactory enzyme inhibitory potency in nanomolar concentrations against AChE and CA isoforms with K I values ranging from 10.14 ± 0.03 to 100.58 ± 1.90 nM. Amine group containing derivatives showed high metal reduction activity and about 70% ABTS radical scavenging activity. Due to their antioxidant activity and AChE inhibition, these novel compounds may be considered as leads for investigations in neurodegenerative diseases.

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.

pathogen for humans. 4 Steroid biotransformations by A. candidus have not been described in the literature. In this work, dehydroepiandrosterone 1, progesterone 2 and pregnenolone 3 were incubated with A. candidus MRC 200634 for 5 days.Incubation of dehydroepiandrosterone 1 with A. candidus MRC 200634 for 5 days afforded six metabolites (Table 1). The first metabolite was identified as 3β,17β-dihydroxyandrost-5-ene 4 (Fig. 1). The metabolite had a new resonance (1H, t, J = 8.5 Hz) at δ H 3.65 ppm in its 1 H NMR spectrum and showed an upfield shift (Δ 0.11 ppm) for the 18-methyl resonance of the starting material, suggesting the presence of a 17β-hydroxy group. The 13 C NMR spectrum of the metabolite lacked the C-17 resonance of 1 at δ C 221.30 ppm and had a new carbon atom resonance at δ C 81.87 ppm (Table 2), which were in accordance with the reduction at C-17.The second metabolite was identified as 6β,17βdihydroxyandrost-4-en-3-one 5. The metabolite showed characteristic resonances at δ H 4.34 ppm 5 (1H, bs) and δ C 72.56 ppm 6 , suggesting the presence of a 6β-hydroxy group. The 1 H NMR spectrum of the metabolite lacked the 3-H resonance of starting material at δ H 3.46 ppm (1H, tt, J = 5.0 and 12.0 Hz) and the double bond resonance of 1 at δ H 5.35 ppm (1H, d, J = 5.0 Hz) had an important downfield shift to δ H 5.82 ppm (∆ 0.47 ppm), suggesting that the 5-en-3β-hydroxy moiety of 1 was converted into the 4-en-3-keto moiety. The 1 H NMR spectrum of the metabolite demonstrated a significant downfield shift (∆ 0.37 ppm) for the 19-methyl group, further suggesting the presence of the 4-en-3-keto moiety. The metabolite had a new resonance (1H, t, J = 8.5 Hz) at δ H 3.65 ppm in its 1 H NMR spectrum and showed an upfield shift (Δ 0.05 ppm) for the

Fungal steroid biotransformations have been widely used for a long time in order to convert and synthesize steroids due to their remarkable regio-and stereo-selectivities. 1 Aspergillus species have been extensively studied in the context of mycotoxin production, pathogenicity, fundamental eukaryotic genetics and in biotechnology. 2 They are ubiquitous fungi found in soil, water and decaying materials. A few Aspergillus species are considered pathogenic to humans and animals. 3 The fungus Aspergillus sydowii is a mesophilic soil and marine saprophyte and it is a food contaminant and an opportunistic pathogen for humans. 4 Biotransformations of steroids by A. sydowii have not been described in the literature. In this work, testosterone 1, dehydroepiandrosterone 2, progesterone 3 and pregnenolone 4 were incubated with A. sydowii MRC 200653 for 5 days.Incubation of testosterone 1 with A. sydowii MRC 200653 for 5 days yielded three metabolites (Table 1). The first metabolite was identified as 6β,17β-dihydroxyandrost-4-en-3-one 5 (Fig. 1). The metabolite had new resonances at δ H 4.35 ppm (1H, bs) 5 and δ C 72.57 ppm 6 (Table 2), which were characteristic of a 6β-hydroxy group. The 1 H NMR spectrum of the metabolite showed a downfield shift (∆ 0.10 ppm) for the 4-H resonance of 1 at δ H 5.71 ppm (1H, s), supporting the presence of a 6β-hydroxy group. The 13 C NMR spectrum of the metabolite showed a downfield shift for C-7 (∆ 5.77 ppm), whereas it showed a γ-gauche upfield shift for C-8 (∆ 5.53 ppm), further supporting the presence of a 6β-hydroxy group.The second metabolite was identified as 14α,17βdihydroxyandrost-4-en-3-one 6. The 13 C NMR spectrum of the metabolite had a new carbon resonance at δ C 83.30 ppm, showing the presence of a hydroxy group. There was a significant downfield shift (∆ 0.70 ppm) for the 17α-H resonance suggesting a diaxial interaction with a 14α-hydroxy group. The 13 C NMR spectrum of the metabolite showed downfield shifts for C-8 (∆ 3.66 ppm) and C-15 (∆ 3.15 ppm) and there were γ-gauche upfield shifts for C-9 (∆ 6.78 ppm) and C-16 (∆ 0.12 ppm). These shifts revealed that a 14α-hydroxylation had taken place.

In this work, incubations of testosterone, dehydroepiandrosterone and pregnenolone with Mucor hiemalis MRC 70325 have been reported. Incubation of testosterone afforded androst-4-en-3,17-dione (3%), 14α-hydroxyandrost-4-en-3,17-dione (9%), 6β-hydroxyandrost-4-en-3,17-dione (2%) and 14α,17β-dihydroxyandrost-4-en-3-one (62%). Incubation of dehy droepiandrosterone afforded 3β,17β-dihydroxyandrost-5-ene (6%) and 3β,7α-dihydroxyandrost-5en-17-one (72%). Incubation of pregnenolone afforded 3β,14α-dihydroxypregn-5-en-7,20-dione (3%), 3β,7α-dihydroxypregn-5-en-20-one (64%) and 3β,7α,11α-trihydroxypregn-5-en-20-one (11%). 3β,14α-Dihydroxypregn-5-en-7,20-dione was identified as a new metabolite.

The incubation of testosterone 1 with Ulocladium chartarum MRC 72584 has been reported. U. chartarum MRC 72584 hydroxylated testosterone 1 at C-7β, C-6β, C-14α and C-12β, accompanied by a 5α-reduction and oxidations at C-6 and at C-17.

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