An Evaluation of the Antibacterial and Antiviral Activities of Some Bryophytes

Document Type : Original Article

Authors

Department of Botany & Microbiology, Faculty of Science, Zagazig University, Zagazig, Egypt.

Abstract

T HIS STUDY screen the antibacterial and antiviral activities of some bryophytes extracts. The pathogenic bacteria Listeria monocytogenes LMG 10470 (L. monocytogenes), Escherichia coli LMG 8223 (E. coli), Bacillus cereus ATCC 14579 (B. cereus) and Pseudomonas aeruginosa LMG 8029 (P. aeruginosa) were inhibited by the aqueous methanolic extracts (ME) of Imbibryum sp., Barbula convoluta and Trichostomum sp.. The mixture of Imbibryum sp.extract and tetracycline have synergistic effect against P. aeruginosa while the mixing of Trichostomum sp. extract with tetracycline has antagonistic effect against P. aeruginosa.Scanning Electron Microscopy (SEM) of P. aeruginosa, treated with ME of Barbula convolute, Imbibryum sp. and Trichostomum sp.indicated sheath surrounded the bacteria, signs of irregular wrinkled outer surface, adhesion and aggregation of damaged cells, malformations in bacterial shape compared to untreated bacterial control. The bryophyte species screened exhibiting considerable antiviral activity against zucchini yellow mosaic virus (ZYMV), so the bryophytes have been identified as a new source of antiviral activity. The highest degree of antiviral activity was shown ME of Barbula convoluta, Imbibryum sp. and Trichostomum sp.against ZYMV (94, 92 and 90%, respectively). The tested cucumber plants which mechanically infected by ZYMV and treated with different extracts of the most potent bryophytes (Imbibryum sp), contain high amount of phenolic compounds. The highest contents of total phenol are detected in infected cucumber plant, which treated with benzene extract of Imbibryum sp.,(3.48 mg/g fresh wt) followed by methanol extract (3.19 mg/g fresh wt). The bryophytes extracts have no toxic effect in Wistar Albino rats.

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