Antibiotic Resistance, Virulence Gene Detection, and Biofilm Formation in Aeromonas spp. Isolated from Fish and Humans in Egypt.

The genus Aeromonas is widely distributed in aquatic environments and is recognized as a potential human pathogen. Some Aeromonas species are able to cause a wide spectrum of diseases, mainly gastroenteritis, skin and soft-tissue infections, bacteremia, and sepsis. The aim of the current study was to determine the prevalence of Aeromonas spp. in raw fish markets and humans in Zagazig, Egypt; identify the factors that contribute to virulence; determine the isolates' profile of antibiotic resistance; and to elucidate the ability of Aeromonas spp. to form biofilms. The examined samples included fish tissues and organs from tilapia (Oreochromis niloticus, n = 160) and mugil (Mugil cephalus, n = 105), and human skin swabs (n = 51) and fecal samples (n = 27). Based on biochemical and PCR assays, 11 isolates (3.2%) were confirmed as Aeromonas spp. and four isolates (1.2%) were confirmed as A. hydrophila. The virulence genes including haemolysin (hyl A) and aerolysin (aer) were detected using PCR in A. hydrophila in percentages of 25% and 50%, respectively. The antimicrobial resistance of Aeromonas spp. was assessed against 14 antibiotics comprising six classes. The resistance to cefixime (81.8%) and tobramycin (45.4%) was observed. The multiple antibiotic resistance (MAR) index ranged between 0.142-0.642 with 64.2% of the isolates having MAR values equal to 0.642. Biofilm formation capacity was assessed using a microtiter plate assay, and two isolates (18.1%) were classified as biofilm producers. This study establishes a baseline for monitoring and controlling the multidrug-resistant Aeromonas spp. and especially A. hydrophila in marine foods consumed in our country to protect humans and animals.

Anti-proliferative, c-Met Inhibitions, and PAINS Evaluations of New Thiophene, Thiazole, Coumarin, Pyran, and Pyridine Derivatives.

BACKGROUND: 1,3-Diones are versatile reagents used for many heterocyclic transformations. Among such groups of compounds, cyclohexane-1,3-dione is widely used in organic synthesis to produce biologically active compounds. OBJECTIVE: In this work, target molecules were synthesized from tetrahydrobenzo[b]thiophen-3- carboxamide derivative with different substituents, and their structure-activity relationships were discussed in detail. METHODS: Cyclohexane-1,3-dione underwent different multi-component reactions to produce fused thiophene, thiazole, coumarin, pyran, and pyridine derivatives. The anti-proliferative activity of the newly synthesized compounds toward the six cancer cell lines, namely A549, H460, HT-29, MKN-45, U87MG, and SMMC-7721 was studied. In addition, inhibitions of the most active compounds toward cancer cell lines classified according to the disease were also studied. Furthermore, Pan Assay Interference compounds (PAINS) of the selected compounds were analyzed, along with the c- Met inhibitions. RESULTS: Anti-proliferative evaluations were performed for all of the synthesized compounds, in which the varieties of substituents through the aryl ring and the heterocyclic ring afforded compounds with high activities. Inhibition activity against the cancer cell lines classified according to the disease, c-Met, and PAINS of the synthesized compounds were measured. CONCLUSION: Compounds 3, 13a, 13b, 14a, 16f, 17a, 28, 30a, and 31were the most cytotoxic compounds toward the six cancer cell lines. Inhibition toward cancer cell lines classified according to the disease showed that, in most cases, the presence of the electronegative CN and or Cl groups within the molecule was responsible for its high activity.

Chemical Constitution and Antimicrobial Activity of Kombucha Fermented Beverage.

Kombucha is a traditional beverage of sweetened black tea fermented with a symbiotic association of acetic acid bacteria and yeasts. In this study, kombucha fermented beverage (KFB) appeared to include nine chemical groups (alcohols, acids, lactones, condensed heterocyclic compounds, antibiotics, esters, aldehydes, fatty acids, and alkaloids) of many bioactive metabolites, as elucidated by gas chromatography-mass spectrometry (GC-MS) and IR spectra. The fermented metabolic components of KFB seem collectively to act in a synergistic action giving rise to the antimicrobial activity. Four types of kombucha preparations (fermented, neutralized, heat-treated and unfermented) were demonstrated with respect to their antimicrobial activity against some pathogenic bacterial and fungal strains using agar well diffusion assay. KFB exerted the strongest antimicrobial activities when compared with neutralized and heat-treated kombucha beverages (NKB and HKB). Staphylococcus aureus ATCC6538 (S. aureus) and Escherichia coli ATCC11229 (E. coli) were the organisms most susceptible to the antimicrobial activity of kombucha beverage preparations. Finally, the KFB preparation showed remarkable inhibitory activity against S. aureus and E. coli bacteria in a brain heart infusion broth and in some Egyptian fruit juices (apple, guava, strawberry, and tomato). These data reveal that kombucha is not only a prophylactic agent, but also appears to be promising as a safe alternative biopreservative, offering protection against pathogenic bacteria and fungi.

Chemical Constitution and Antimicrobial Activity of Kefir Fermented Beverage.

Kefir beverage (KB) is a fermented milk initiated by kefir grains rich with starter probiotics. The KB produced in this study seemed to contain many chemical compounds elucidated by gas chromatography-mass spectrometry (GC-MS) and IR spectra. These compounds could be classified into different chemical groups such as alcohols, phenols, esters, fatty esters, unsaturated fatty esters, steroids, polyalkenes, heterocyclic compounds and aromatic aldehydes. Both KB and neutralized kefir beverage (NKB) inhibited some pathogenic bacteria including Escherichia coli ATCC11229 (E. coli), Listeria monocytogenes ATCC 4957 (L. monocytogenes), Bacillus cereus ATCC 14579 (B. cereus), Salmonella typhimurium ATCC 14028 (Sal. typhimurium) as well as some tested fungal strains such as Aspergillus flavus ATCC 16872 (A. flavus) and Aspergillus niger ATCC 20611 (A. niger), but the inhibitory activity of KB was more powerful than that obtained by NKB. It also appeared to contain four lactic acid bacteria species, one acetic acid bacterium and two yeast species. Finally, the KB inhibited distinctively both S. aureus and Sal. typhimurium bacteria in a brain heart infusion broth and in some Egyptian fruit juices, including those made with apples, guava, strawberries and tomatoes.

New approaches for the synthesis of thiophene derivatives with anti-tumor activities.

The reaction of either cyclohexanone or cyclopentanone with cyanoacetylhydrazine and elemental sulfur gave the 2-aminocycloalkeno[b]thiophene derivatives 3a and 3b, respectively. The latter compounds reacted with either aromatic benzaldehydes or active methylene reagents to give the Schiff's bases 5a-d and the pyrazole derivatives 7a-d and 9a-d, respectively. On the other hand, the reaction of 3-oxo-N-p-tolylbutanamide (10) with either of malononitrile or ethyl cyanoacetate gave the thiophene derivatives 13a and 13b, respectively. Compounds 13a,b were subjected to a series of heterocyclization reactions to give heterocyclic derivatives. Their cytotoxicity against the three human tumor cells lines, namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) together against the normal human cell line namely the normal fibroblast cells WI 38 were measured.