Biological Characterization and Inhibition of <i>Streptococcus pyogenes</i> ZUH1 Causing Chronic Cystitis by <i>Crocus sativus</i> Methanol Extract, Bee Honey Alone or in Combination with Antibiotics: An In Vitro Study

• Main Authors: Seham Abdel-Shafi, Abdul-Raouf Al-Mohammadi, Sara Hamdi, Ahmed H. Moustafa, Gamal Enan
• Format: Article
• Language: English
• Published: MDPI AG 2019-08-01
• Series: Molecules
• Subjects: Group A streptococci (GAS); <i>S. pyogenes</i> ZUH1; virulence factors; <i>Crocus sativus</i>; CSME; GC-MS; IR analysis; transmission electron microscopy (TEM)
• Online Access: https://www.mdpi.com/1420-3049/24/16/2903

<i>Streptococcus pyogenes</i> (<i>S. pyogenes</i>) ZUH1 was isolated and characterized using morphological, cultural and biochemical methods. The results showed that the marker genes (namely spyCEP, ssa, sic, sdaB and speG) indicating group A streptococci (GAS) were detected in the <i>S. pyogenes</i> genome. The results showed that the <i>S. pyogenes</i> strain was inhibited by <i>Crocus sativus</i> methanol extract (CSME), bee honey (BH) and catfish glycoprotein (CFG). The inhibitory activity of these natural agents were compared with standard antibiotics such as Ceftazidime (30 &#956;g/mL), Cefoperazone (75 &#956;g/mL), Cefoxitin (30 &#956;g/mL) and Imipenem (10 &#956;g/mL). There was a synergistic effect between certain antibiotics and CSME. GC-MS and IR analysis of CSME showed different cyclic ketones, aldehydes, esters, alcohols and acids. The main compounds were tetradecanoic acid, safranal and isophorone. Transmission electron microscopy (TEM) images of <i>S. pyogenes</i> cells treated with CSME showed signs of an irregular wrinkled outer surface, fragmentation, adhesion and aggregation of damaged bacterial cells or cellular debris. The marker genes (spyCEP, ssa, sic, sdaB and speG) could be used as a rapid diagnostic tool for GAS. CSME, BH and CFG showed distinctive anti-streptococcal activity either alone or in combinations with antibiotics; their action on <i>S. pyogenes</i> cells was studied by TEM. There was a synergistic effect between antibiotics and <i>Crocus sativus</i>, bee honey, and glycoprotein against<i> S. pyogenes</i> ZUH1. The action of natural agents on the pathogenic cells was shown using TEM.