a b s t r a c tIn this study, inhibition of Escherichia coli glucuronidase (GUS) by a plant extract of Pistacia terebinthus was investigated. P. terebinthus (from Karaburun region in Turkey) leaf extract exhibits various bioactivities, such as antioxidant, antimicrobial and cytotoxic property because of its flavonoid, phenolic and alkaloid contents. HPLC analyses were performed to evaluate the composition of the extract and main flavonoid compounds such as luteolin, luteolin-7-glucoside and apigenin-7-glucoside were detected in extract. GUS activity and kinetic data of the GUS were obtained by measuring rate of production of resulting fluorescent 4-methylumbelliferone (4-MU) and phenolphthalein fluorometrically and spectrophotometrically, respectively. Plant leaves showed higher antioxidant capacity as 85 TEAC (trolox equivalent antioxidant capacity) value and higher antimicrobial activity towards Staphylococcus aureus. 92.4% GUS enzyme inhibition was achieved with 8.3 g ml −1 crude extract concentration, where IC 50 value was found as 2.1 (±0.2) g ml −1 . Kinetic studies by nonlinear regression revealed that inhibition type caused by plant extract was mixed type (noncompetitive and competitive together). K m and V max values were 96.94 ± 9.68 nM and 7.81 ± 0.16 nmol min −1 mg −1 , respectively. Inhibition constant (˛K i ) was found as 7.00 ± 0.93 nM having˛value 2.17 ± 0.93. Our results may provide useful information regarding the inhibition of microbial GUS activity, preventing deglucuronidation and reducing possible cancer risk by bioactive P. terebinthus crude extract.

The aim of this study is to investigate the changes in quality characteristics of Turkish delight as influenced by different concentrations of cornelian cherry pulp. A 4.4 and 12.2% cornelian cherry pulp added Turkish delight samples were produced in industrial conditions. Samples were packaged and stored for 20 weeks. Results showed that samples preserved their microbiological stability during storage. Pulp addition resulted in a decrease in L* values (from 57.32 to 30.67) and provided intensive lokum colors. Total sugar and dry matter contents of the samples varied 76.4–83.3% and 80.33–88.84, respectively. Texture profile analysis (TPA) results showed that initial maximum hardness value was 455.02 N, and it reduced to 189.72 N at the end of 20 months storage. The fruity taste was considered as a desirable sensorial attribute in the sensory analysis. Practical applications The cornelian cherry fruits are rich in healthy constituents and natural coloring pigments. They have a considerable potential as food ingredient. In this study, cornelian cherry is successfully used in the production of the one of the oldest sweets in the world, known as “Turkish Delight.” The present study outlines that cornelian cherry can be commercially used for the enrichment of Turkish delight in terms of providing a natural color and taste as well as having high desirability and satisfactory quality attributes. In future studies, cornelian cherry fruit can be used as a food ingredient to produce various functional confectionaries.

Vegetable oils are used as milk fat replacers in cheese production to alter sensory, nutritional profile, and to produce cholesterol free or low-cost cheeses. The aim of this study is to investigate the effect of palm oil usage on kashar cheese's physicochemical, textural and sensorial quality characteristics during ripening. The results showed that replacement of milk fat with palm oil was not statistically significant in terms of moisture, salt, fat content, and titratable acidity. β-sitosterol content, which is a marker of vegetable oil addition in cheese, was found in the detectable range by chromatographic analysis for the palm oil added samples (PD). Hardness, chewiness, and gumminess values were significantly affected by the palm oil replacement and also during the ripening period of 90 days. Changes in L* values were apparent during ripening and the brightness of the PD groups was lower than that of the control group. Higher sensorial scores for PD indicated that palm oil usage may not be noticeable by the consumers. The overall results provide essential information, demonstrating that cost-saving palm oil can be successfully used in kashar cheese production where the milk fat replacement did not alter the physicochemical, textural and sensorial quality characteristics.

The use of the clinoptilolite rich natural zeolites in biomedical applications such as in anticancer therapy, drug or drug support systems and as nutritive supplement is highly dependent on their behavior in digestive conditions. Aim of this study is to investigate structural stability of clinoptilolite rich natural zeolites in simulated digestion conditions and their interactions with digestive media and with Caco-2 (human colon adenocarcinoma) cells. X-ray Diffraction (XRD), Fourier Transform InfraRed (FTIR), Scanning Electron Microscopy (SEM) and Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) analyses of the clinoptilolite rich zeolite samples showed that zeolites preserved their structural stabilities during in vitro digestion. Slight interactions were detected in UV measurements of the digestive liquid media and FTIR spectra of the intestinal digested media powders. SEM results implied that zeolites might have a role in the aggregation of the digestive enzymes. Cytotoxicity test using colon cancer cells showed that clinoptilolite rich natural zeolites have cytotoxic effect against Caco-2 cells and cytotoxicity did not significantly change with respect to simulated digestion process.

This study aimed to optimize the extraction conditions for Sorbus umbellata (Desf.) Fritsch var. umbellata leaves to maximize the phenolic content and their antioxidant activity and to investigate β-glucuronidase (GUS) enzyme inhibitory, antimicrobial and cytotoxic potentials of the extracts obtained under optimum conditions. The optimum extraction conditions were found to be 78.2 and 79.7% solvent, 73.1 and 71.5°C, and 89.9 and 88.8 min to maximize phenolic content and antioxidant activity, respectively. Low values of coefficient of variations indicate the high reliability and reproducibility of the conducted extraction experiments. Bioactivity results showed that extracts had cytotoxic effect on the MCF-7 and A549 cells where the highest cell proliferation inhibition was observed for the A549 cell line (71.8% at 150 μg/mL). Staphylococcus aureus showed highest zone of inhibition (19.3 mm) in all bacteria followed by Escherichia coli. Additionally, extracts displayed potential GUS inhibitory activity. In conclusion, Sorbus umbellata leaf extract can be obtained by optimized cost-saving extraction and has a potential bioactivity to be utilized as a food ingredient for high value-added products and/or nutraceuticals development where it can combat oxidative stress and GUS mediated reactive metabolite formation.

The aim of this study is to obtain the grape seed extract with high antioxidant activity and to investigate the quality characteristics of traditional yogurts fortified with seed extracts at different concentrations. For this aim, batch hot water extraction was conducted and extraction conditions were optimized to produce Vitis vinifera L. grape seed extract using with the highest antioxidant activity. The fortification of yogurts was conducted at 0.1-0.15 and 0.2 g/ 100g extract level and antioxidant, physicochemical, microbial and sensory characteristics of the yogurt samples were analyzed. Results showed that antioxidant activity of fortified yogurts were higher and up to 14 % more antioxidant activity was detected compared to the control samples. Yogurt samples preserved their physicochemical characteristics. Although sample with 0.1 g/100 g extract had highest scores in overall acceptance, the sample containing the highest extract concentration of 0.2 g/100 g, exhibited negative perceptions by panelists in sensorial analysis. In conclusion, grape seed may be used in traditional yogurt production by improving the taste and antioxidant potential. The fortification levels of 0.1-0.15 g/100 g grape seed extract might be more feasible in functional yogurt production and might be more recommended for consumer's appreciation in terms of positive health effects.

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a b s t r a c tThe adsorption of the bacterial ␤-glucuronidase (GUS) enzyme, which is thought to be responsible for the production of reactive metabolites related to some diseases and cancer development, by clinoptiloliterich mineral was investigated. Batch experiments were performed to analyze of the effects of the clinoptilolite amount and particle size, initial GUS concentration, shaking rate, pH and temperature on the adsorption equilibrium and kinetics. Adsorption equilibrium data were interpreted in terms of Langmuir and Freundlich isotherms; and they were well represented by the Langmuir isotherm model. The percentage of GUS removal by the clinoptilolite-rich mineral was changed in the range of 9.4-54.4% depending on its initial concentration. The kinetic data were analyzed using external film diffusion, intraparticle diffusion, pseudo-first-order and pseudo-second-order models and both external film and intraparticle diffusion appeared to be effective in GUS adsorption. Thermodynamic studies indicated that GUS adsorption is exothermic, physical and spontaneous at the temperatures investigated (288-310 K).