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1.
Foods ; 13(11)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38890888

RESUMO

The post-harvest processing of coffee beans leads to a wide range of reactions involving proteins. The formation of crosslinks between proteins and phenolic compounds present in high concentrations of coffee beans represents one of the most challenging and still not fully characterized reactions. The aim of this work was to assess the presence of products from such reactions in coffee samples, focusing on the adducts between cysteine and chlorogenic acids (CQAs). For this purpose, 19 green and 15 roasted coffee samples of the Coffea arabica, Coffea canephora, and Coffea liberica varieties were selected for this study and basically characterized. Then, targeted liquid chromatography mass spectrometry (LC-MS/MS) methods were developed to assess the formation of adducts between CQA and cysteine, glutathione, and N-acetylcysteine as the amino acid and peptide models, and quantified such adducts in coffee samples. The results of the characterization showed a heterogeneous distribution of the protein content (8.7-14.6%), caffeine (0.57-2.62 g/100 g), and antioxidant capacity (2-4.5 g ascorbic acid/100 g) in Arabica, Canephora, and Liberica samples. Glutamic acid, arginine, and proline were found to be the major amino acids, while 5-CQA (38-76%), 3-CQA (4-13%), and 4-CQA (4-13%) were the most abundant CQA derivatives of all coffee varieties. The model experiments for adduct formation demonstrated that cysteine binds to CQA via thiol groups and 5-CQA initially isomerizes to 3- and 4-CQA, depending on the conditions, allowing cysteine to bind to two different sites on 3-, 4- or 5-CQA molecules, thus, forming six different Cys-CQA adducts with m/z 476. The reaction was more favored at pH 9, and the adducts proved to be stable up to 90 °C for 10 min and up to 28 days at room temperature. The relative quantification of adducts showed peak area values ranging from 1100 to 3000 in green coffee bean samples, while no adducts were detected in roasted coffee beans. Overall, this work was the first attempt to demonstrate the presence of Cys-CQA adducts in coffee beans and paves the way for further investigations of such adduct formation at the protein level.

2.
Polymers (Basel) ; 15(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36771990

RESUMO

In this original research, biodegradable corn starch (CS) and wheat gluten (wg)-based silver nanofilms were synthesized and analyzed by using goji berry extract taurine (ta), garlic extract (GC), whey powder (wh), and montmorillonite clay nanoparticles. Antibacterial-corn-starch-based nano films were analyzed by using the methods of high-performance liquid chromatography (HPLC), Fourier Transform infrared spectroscopy (FTIR-ATR), X-ray diffraction (XRD), dynamic and mechanical (DMA) analysis, and scanning electron microscopy (SEM). In addition, the antibacterial resistances of the corn starch nano films against the bacteria Salmonella and Staphylococcus aureus (S. aureus) and Listeria monocytogenes were examined and the migration assays were carried out. The migration analysis results of CS1, CS2, and CS3 nanocomposite films were found as 0.305, 0.297, and 0.297 mg/dm2, respectively. The inhibition zone of CS1, CS2, and CS3 nanocomposite films were found as 1547, 386, and 1884 mm2 against Salmonella bacteria. The results show that silver nanofilms are suitable as packaging films for the production of packaging in milk and dairy products, liquid foods, and acidic foods.

3.
Heredity (Edinb) ; 129(6): 346-355, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36319737

RESUMO

Cat domestication likely initiated as a symbiotic relationship between wildcats (Felis silvestris subspecies) and the peoples of developing agrarian societies in the Fertile Crescent. As humans transitioned from hunter-gatherers to farmers ~12,000 years ago, bold wildcats likely capitalized on increased prey density (i.e., rodents). Humans benefited from the cats' predation on these vermin. To refine the site(s) of cat domestication, over 1000 random-bred cats of primarily Eurasian descent were genotyped for single-nucleotide variants and short tandem repeats. The overall cat population structure suggested a single worldwide population with significant isolation by the distance of peripheral subpopulations. The cat population heterozygosity decreased as genetic distance from the proposed cat progenitor's (F.s. lybica) natural habitat increased. Domestic cat origins are focused in the eastern Mediterranean Basin, spreading to nearby islands, and southernly via the Levantine coast into the Nile Valley. Cat population diversity supports the migration patterns of humans and other symbiotic species.


Assuntos
Domesticação , Repetições de Microssatélites , Animais , Gatos/genética , Genótipo , Oriente Médio
4.
J Biomater Sci Polym Ed ; 33(8): 995-1011, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35044283

RESUMO

In this study, the chitosan, a polysaccharide, was encapsulated with the bee pollen and the apple cider vinegar. The freeze-drying method was used in the encapsulation process. The freeze cooling temperature was determined as -80 °C. The obtained encapsulated chitosan compounds were analyzed by Fourier Transform Infrared Spectroscopy (FTIR) and their molecular weights were determined by the cryoscopy method. The total amount of the phenol compounds and % the antioxidant activity of the synthesized compounds were measured by UV spectrophotometer and, the loading capacity of the polyphenol compounds in encapsulation was determined. The success of encapsulation was calculated based on the % encapsulation efficiency (%EE) calculation. The antibacterial and the surface activity properties of the obtained CSx and CSy compounds were analyzed against Listeria monocytogenes, Staphylococcus aureus, E. coli and Salmonella bacteria using the well diffusion method and the Zeiss microscope.


Assuntos
Quitosana , Malus , Ácido Acético , Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Abelhas , Quitosana/química , Escherichia coli , Malus/microbiologia , Pólen
5.
Foods ; 9(10)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066015

RESUMO

The α-amylase/trypsin inhibitors (ATIs) are discussed as being responsible for non-celiac wheat sensitivity (NCWS), besides being known as allergenic components for baker's asthma. Different approaches for characterization and quantification including proteomics-based methods for wheat ATIs have been documented. In these studies generally the major ATIs have been addressed. The challenge of current study was then to develop a more comprehensive workflow encompassing all reviewed wheat-ATI entries in UniProt database. To substantially test proof of concept, 46 German and Turkish wheat samples were used. Two extractions systems based on chloroform/methanol mixture (CM) and under buffered denaturing conditions were evaluated. Three aspects were optimized, tryptic digestion, chromatographic separation, and targeted tandem mass spectrometric analysis (HPLC-MS/MS). Preliminary characterization with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) documented the purity of the extracted ATIs with CM mixture and the amylase (60-80%)/trypsin (10-20%) inhibition demonstrated the bifunctional activity of ATIs. Thirteen (individual/common) biomarkers were established. Major ATIs (7-34%) were differently represented in samples. Finally, to our knowledge, the proposed HPLC-MS/MS method allowed for the first time so far the analysis of all 14 reviewed wheat ATI entries reported.

6.
Turk J Gastroenterol ; 30(3): 242-253, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30662004

RESUMO

BACKGROUND/AIMS: Kefir is a kind of fermented probiotic dairy product. The objective of the present study was to investigate the effects of kefir consumption on the fecal microflora and symptoms of patients with inflammatory bowel disease (IBD). MATERIALS AND METHODS: Kefir was serially diluted and inoculated into de Man, Rogosa, and Sharpe agar and incubated at 37°C for 48 to 72 h under anaerobic conditions. This was a single-center, prospective, open-label randomized controlled trial. Forty-five patients with IBD were classified into two groups: 25 for treatment and 20 for control. A 400 mL/day kefir was administered to the patients for 4 weeks day and night. Their stool Lactobacillus, Lactobacillus kefiri, content was quantitated by real-time quantitative polymerase chain reaction before and after consumption. Abdominal pain, bloating, stool frequency, stool consistency, and feeling good scores were recorded in diaries daily by the patients. RESULTS: A 5×107 CFU/mL count of lactic acid bacteria colony forming units was found in a kefir sample as the total average count. Lactobacillus bacterial load of feces of all subjects in the treatment group was between 104 and 109 CFU/g, and the first and last measurements were statistically significant (p=0.001 in ulcerative colitis and p=0.005 in Crohn's disease (CD)). The L. kefiri bacterial load in the stool of 17 subjects was measured as between 104 and 106 CFU/g. For patients with CD, there was a significant decrease in erythrocyte sedimentation rate and C-reactive protein, whereas hemoglobin increased, and for the last 2 weeks, bloating scores were significantly reduced (p=0.012), and feeling good scores increased (p=0.032). CONCLUSION: According to our data, kefir consumption may modulate gut microbiota, and regular consumption of kefir may improve the patient's quality of life in the short term.


Assuntos
Fezes/microbiologia , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/terapia , Kefir/microbiologia , Probióticos/uso terapêutico , Adulto , Carga Bacteriana , Sedimentação Sanguínea , Proteína C-Reativa/análise , Colite Ulcerativa/sangue , Colite Ulcerativa/microbiologia , Colite Ulcerativa/terapia , Doença de Crohn/sangue , Doença de Crohn/microbiologia , Doença de Crohn/terapia , Feminino , Humanos , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/microbiologia , Lactobacillus/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
7.
Braz J Microbiol ; 47(2): 444-51, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26991276

RESUMO

Presence of extended spectrum beta-lactamases (ESBL) in bacteria is a growing health concern of global significance. The local, regional, national, and international epidemiological studies for extended spectrum beta-lactamases-producing Enterobacteriaceae and their encoding genes in foods are still incomplete. The objective of this study was to determine the occurrence of extended spectrum beta-lactamases-producing Enterobacteriaceae and the characteristics of their encoding genes from a total of 250 samples of various foods of animal-origin (100 raw chicken meat, 100 raw cow milk, and 50 raw cow milk cheese) sold in Turkey. Overall, 55 isolates were positive as extended spectrum beta-lactamases-producing Enterobacteriaceae. The most prevalent extended spectrum beta-lactamases-producing strain were identified as Escherichia coli (80%), followed by Enterobacter cloacae (9.1%), Citrobacter braakii (5.5%), Klebsiella pneumoniae (3.6%), and Citrobacter werkmanii (1.8%) by Vitek(®) MS. The simultaneous production of extended spectrum beta-lactamases and AmpC was detected in five isolates (9.1%) in E. coli (80%) and E. cloacae (20%). The frequency rates of blaTEM, blaCTX-M, and blaSHV were 96.4%, 53.7%, and 34.5%, respectively. The co-existence of bla-genes was observed in 82% of extended spectrum beta-lactamases producers with a distribution of blaTEM &blaCTX-M (52.7%), blaTEM &blaSHV (20%), blaTEM &blaCTX-M &blaSHV (12.7%), and blaSHV &blaCTX-M (1.8%). The most prevalent variant of blaCTX-M clusters was defined as blaCTX-M-1 (97.2%), followed by blaCTX-M-8 (2.8%). In summary, the analysed foods were found to be posing a health risk for Turkish consumers due to contamination by Enterobacteriaceae with a diversity of extended spectrum beta-lactamases encoding genes.


Assuntos
Proteínas de Bactérias/metabolismo , Queijo/microbiologia , Enterobacteriaceae/isolamento & purificação , Carne/microbiologia , Leite/microbiologia , beta-Lactamases/metabolismo , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Bovinos , Galinhas , Farmacorresistência Bacteriana Múltipla , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Microbiologia de Alimentos , Turquia , beta-Lactamases/genética
8.
Genomics ; 91(1): 12-21, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18060738

RESUMO

The diaspora of the modern cat was traced with microsatellite markers from the presumed site of domestication to distant regions of the world. Genetic data were derived from over 1100 individuals, representing 17 random-bred populations from five continents and 22 breeds. The Mediterranean was reconfirmed to be the probable site of domestication. Genetic diversity has remained broad throughout the world, with distinct genetic clustering in the Mediterranean basin, Europe/America, Asia and Africa. However, Asian cats appeared to have separated early and expanded in relative isolation. Most breeds were derived from indigenous cats of their purported regions of origin. However, the Persian and Japanese bobtail were more aligned with European/American than with Mediterranean basin or Asian clusters. Three recently derived breeds were not distinct from their parental breeds of origin. Pure breeding was associated with a loss of genetic diversity; however, this loss did not correlate with breed popularity or age.


Assuntos
Cruzamento , Gatos/genética , Repetições de Microssatélites/genética , Filogenia , Animais , Genética Populacional
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