Comparative Study on the Essential Oils from Five Wild Egyptian <i>Centaurea</i> Species: Effective Extraction Techniques, Antimicrobial Activity and In-Silico Analyses

• Main Authors: Eman H. Reda (Author), Zienab T. Abdel Shakour (Author), Ali M. El-Halawany (Author), El-Sayeda (Author), Khaled A. Shams (Author), Tarik A. Mohamed (Author), Ibrahim Saleh (Author), Abdelsamed I. Elshamy (Author), Mohamed A. M. Atia (Author), Ahmed A. El-Beih (Author), Nahla S. Abdel-Azim (Author), Hesham R. El-Seedi (Author), Mohamed-Elamir F. Hegazy (Author)
• Format: Book
• Published: MDPI AG, 2021-03-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

The genus <i>Centaurea</i> is recognized in folk medicine for anti-inflammatory, anti-itch, antitussive, purgative, astringent, and tonic activities. To study the chemical determinant for antimicrobial activity essential oils (EOs), five <i>Centaurea</i> species were analyzed including: <i>C. scoparia</i>, <i>C. calcitrapa</i>, <i>C. glomerata</i>, <i>C. lipii</i> and <i>C. alexandrina</i>. Conventional hydro-distillation (HD) and microwave-assisted extraction (MAE), as new green technologies, were compared for the extraction of essential oils. GC/MS analysis identified 120 EOs including mostly terpenoid except from <i>C. lipii</i> and <i>C. alexandrina</i> in which nonterpenoids were the major constituents. Major terpenoids included spathulenol, caryophyllene oxide and alloaromadendrene oxide-2. To probe antibacterial activity, potential EO inhibitors of a bacterial type II DNA topoisomerase, DNA gyrase B were screened via an in silico molecular docking approach. Spathulenol and alloaromadendrene oxide-2 possessed the best binding affinity in the ATP- binding pocket of Gyrase B enzyme. Principal component analysis and agglomerative hierarchical clustering were used for sample classification and revealed that sesquiterpenes contributed the most for accessions classification. In vitro antimicrobial activity against <i>Staphylococcus aureus</i>, <i>Escherichia coli</i> and <i>Aspergillus niger</i> for all EOs were also evaluated. EOs from <i>C. lipii</i>, <i>C. glomerata</i> and <i>C. calcitrapa</i> exhibited significant MIC against <i>S. aureus</i> with an MIC value of 31.25 µg/mL.

Item Description

10.3390/antibiotics10030252
2079-6382