Limits...
Flavone Biotransformation by Aspergillus niger and the Characterization of Two Newly Formed Metabolites.

Mahmoud YA, Assawah SW, El-Sharkawy SH, Abdel-Salam A - Mycobiology (2008)

Bottom Line: Antioxidant activities of the two isolated metabolites were tested compared with ascorbic acid.Antioxidant activity of metabolite (1) was recorded 64.58% which represented 79% of the antioxidant activity of ascorbic acid, and metabolite (2) was recorded 54.16% (67% of ascorbic acid activity).However, the antioxidant activity of flavone was recorded 37.50% which represented 46% of ascorbic acid activity.

View Article: PubMed Central - PubMed

Affiliation: Tanta University, Faculty of Science, Botany Department, Mycology Research Lab., Tanta 31527, Egypt.

ABSTRACT
Aspergillus niger isolated from Allium sativum was used at large scale fermentation (150 mg flavone/200 ml medium) to obtain suitable amounts of the products, efficient for identification. Then spectral analysis (UV, IR, (1)H-NMR, (13)C-NMR) and mass spectrometry were performed for the two products, which contributed to the identification process. The metabolite (1) was identified as 2'-hydroxydihydrochalcone, and the metabolite (2) was identified as 2'-hydroxyphenylmethylketone, which were more active than flavone itself. Antioxidant activities of the two isolated metabolites were tested compared with ascorbic acid. Antioxidant activity of metabolite (1) was recorded 64.58% which represented 79% of the antioxidant activity of ascorbic acid, and metabolite (2) was recorded 54.16% (67% of ascorbic acid activity). However, the antioxidant activity of flavone was recorded 37.50% which represented 46% of ascorbic acid activity. The transformed products of flavone have antimicrobial activity against Pseudomonas aeruginosa, Aspergillus flavus and Candida albicans, with MIC was recorded 250 µg/ml for metabolite (2) against all three organism and 500, 300, and 300 µg/ml for metabolite (1) against tested microorganisms (P. aeruginosa, Escherichia coli, Bacillus subtilis, and Klebsiella pneumonia, Fusarium moniliforme, A. flavus, Saccharomyces cerviceae, Kluveromyces lactis and C. albicans) at this order.

No MeSH data available.


Related in: MedlinePlus

13C-NMR spectrum of metabolite (1).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3755235&req=5

Figure 4: 13C-NMR spectrum of metabolite (1).

Mentions: Metabolite (1) was produced from transformation of flavone by A. niger. Its UV spectrum λ-max is 305.4, 278.7, 250.2 nm (Fig. 1). Infrared (KBr) showed absorption at 3665, 2852, 1692, 1553, 1535, 1518, 1483, 1448, 1333, 875, 679 cm-1 (Fig. 2). 1H-NMR (DMSO): 4.10 (C-2), 3.68 (2H, C-3), 8.07 (C-5), 7.57 (C-6), 7.67 (C-7), 7.67 (C-8), 8.37 (OH proton) (Fig. 3). 13C-NMR (DMSO): 195.0 (C-4), 163.33 (C-9), 156.28 (C-4'), 132.40 (C-6'), 132.40 (C-2'), 132.10 (C-1'), 129.76(C-7), 129.73 (C-5), 129.70 (C-6), 126.92 (C-10), 119.12(C-3'), 119.12(C-5'), 67.97(O-CH3), 63.50 (C-3), 39.71 (C-2) (Fig. 4). Mass spectrum (direct probe): m/e 272 (M+), 141, 116, 113, 102, 93, 66, 51 (Fig. 5).


Flavone Biotransformation by Aspergillus niger and the Characterization of Two Newly Formed Metabolites.

Mahmoud YA, Assawah SW, El-Sharkawy SH, Abdel-Salam A - Mycobiology (2008)

13C-NMR spectrum of metabolite (1).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3755235&req=5

Figure 4: 13C-NMR spectrum of metabolite (1).
Mentions: Metabolite (1) was produced from transformation of flavone by A. niger. Its UV spectrum λ-max is 305.4, 278.7, 250.2 nm (Fig. 1). Infrared (KBr) showed absorption at 3665, 2852, 1692, 1553, 1535, 1518, 1483, 1448, 1333, 875, 679 cm-1 (Fig. 2). 1H-NMR (DMSO): 4.10 (C-2), 3.68 (2H, C-3), 8.07 (C-5), 7.57 (C-6), 7.67 (C-7), 7.67 (C-8), 8.37 (OH proton) (Fig. 3). 13C-NMR (DMSO): 195.0 (C-4), 163.33 (C-9), 156.28 (C-4'), 132.40 (C-6'), 132.40 (C-2'), 132.10 (C-1'), 129.76(C-7), 129.73 (C-5), 129.70 (C-6), 126.92 (C-10), 119.12(C-3'), 119.12(C-5'), 67.97(O-CH3), 63.50 (C-3), 39.71 (C-2) (Fig. 4). Mass spectrum (direct probe): m/e 272 (M+), 141, 116, 113, 102, 93, 66, 51 (Fig. 5).

Bottom Line: Antioxidant activities of the two isolated metabolites were tested compared with ascorbic acid.Antioxidant activity of metabolite (1) was recorded 64.58% which represented 79% of the antioxidant activity of ascorbic acid, and metabolite (2) was recorded 54.16% (67% of ascorbic acid activity).However, the antioxidant activity of flavone was recorded 37.50% which represented 46% of ascorbic acid activity.

View Article: PubMed Central - PubMed

Affiliation: Tanta University, Faculty of Science, Botany Department, Mycology Research Lab., Tanta 31527, Egypt.

ABSTRACT
Aspergillus niger isolated from Allium sativum was used at large scale fermentation (150 mg flavone/200 ml medium) to obtain suitable amounts of the products, efficient for identification. Then spectral analysis (UV, IR, (1)H-NMR, (13)C-NMR) and mass spectrometry were performed for the two products, which contributed to the identification process. The metabolite (1) was identified as 2'-hydroxydihydrochalcone, and the metabolite (2) was identified as 2'-hydroxyphenylmethylketone, which were more active than flavone itself. Antioxidant activities of the two isolated metabolites were tested compared with ascorbic acid. Antioxidant activity of metabolite (1) was recorded 64.58% which represented 79% of the antioxidant activity of ascorbic acid, and metabolite (2) was recorded 54.16% (67% of ascorbic acid activity). However, the antioxidant activity of flavone was recorded 37.50% which represented 46% of ascorbic acid activity. The transformed products of flavone have antimicrobial activity against Pseudomonas aeruginosa, Aspergillus flavus and Candida albicans, with MIC was recorded 250 µg/ml for metabolite (2) against all three organism and 500, 300, and 300 µg/ml for metabolite (1) against tested microorganisms (P. aeruginosa, Escherichia coli, Bacillus subtilis, and Klebsiella pneumonia, Fusarium moniliforme, A. flavus, Saccharomyces cerviceae, Kluveromyces lactis and C. albicans) at this order.

No MeSH data available.


Related in: MedlinePlus