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    Chemical and physical characterization of microencapsulated Spirulina fermented with Lactobacillus plantarum
    (Elsevier, 2023) Ozyurt, Gulsun; Uslu, Leyla; Durmus, Mustafa; Sakarya, Yetkin; Uzlasir, Turkan; Kuley, Esmeray
    Spirulina fermented by lactic acid bacteria (LAB) stands out among innovative fermented products with bioactive properties. In addition, the fermentation of algae with LAB has a significant effect on protein, essential amino acid content, essential fatty acid, etc. Changes in nutritional components, colour and morphological appearances of unfermented and fermented Spirulina as a result of microencapsulation with different ratios of coating material were investigated. The fermentation of wet Spirulina was carried out with Lactobacillus plantarum FI 8595 at 37 degrees C for 72 h under anaerobic condition. Microencapsulation of unfermented (USp) and fermented Spirulina (FSp) was performed by spray drying using 170 degrees C air inlet temperature, 20 mL/min feed flow rate and different ratios of maltodextrin. After fermentation, there was an increase in dry matter and crude ash contents unlike the protein content. Aspartic acid, histidine and lysine concentrations were found to be significantly higher in FSp compared to USp. The main fatty acids in USp and FSp were palmitic (27.39-31.11 %), gamma linolenic (17.41-18.93 %), linoleic (8.11-10.45 %) and palmitoleic acids (4.36-5.05 %). A significant decrease was observed in the phycocyanin content of Spirulina after fermentation. However, the highest total organic acid content was observed in spray dried fermented Spirulina groups (9-22 g/100 g). Increasing maltodextrin (MD) concentrations caused a significant reduction in moisture content of USp and FSp and provided more effective drying. In addition, with the increase of MD addition, the essential/nonessential amino acid ratio raised from 0.83 to 1.26 and from 0.72 to 0.76 in USp and FSp, respectively. According to the SEM results, it was observed that the fermented Spirulina were coated more effectively with the coating material. In addition, fermentation and microencapsulation revealed positive effects on colour properties of Spirulina. Therefore, it can be concluded that microencapsulation of fermented Spirulina has significant potential for the production of new functional foods.
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    Comparison of phenolic profile and some physicochemical properties of Uzun pistachios as influenced by different harvest period
    (Wiley, 2020) Kelebek, Haşim; Sönmezdağ, Ahmet S.; Güçlü, Gamze; Cengiz, Nurten; Uzlasir, Turkan; Kadiroglu, Pinar; Selli, Serkan
    Pistachios, which are among the top 50 healthiest foods, are rich in antioxidants and are a major source of phenolic compounds known for their related antioxidant benefits. The ripening stage is of paramount importance for food processing since the chemical composition of this fruit is heavily influenced by its level of maturity. For instance, immature pistachios are preferred to be used in desserts, sauces, ice-creams, and chocolate, while mature pistachios are more often consumed as a roasted snack. In this study, the changes in color properties, fatty acids, phenolic compounds, and antioxidant activity at four different maturity periods of the Turkish Uzun pistachio variety were investigated. A total of 13 phenolic compounds were identified and characterized by LC-DAD-ESI/MSn, with a total amount varying between 136 and 210 mg/kg. Catechin, daidzin, and genistin accounted for the highest amount of the total phenolics. The phenolic compounds and antioxidant capacities of the pistachios decreased as the maturation period extended and these two parameters displayed a linear correlation. With regard to fatty acids, Oleic acid had the highest concentration in all the samples, followed by Linoleic and Palmitic acids. The oil yield and fatty acids of pistachio also increased as maturation periods extended in the samples. Practical applications Pistachios have a high nutritional value and many health benefits, with their rich content of phenolic compounds and fatty acids. The ripening period could lead to differences in phenolic compounds and other bioactive properties. The findings of this research could be helpful to determine the optimal maturity index of the pistachios for their usage in specific foods. Thus, it may lead to a decrease in production costs, with use of the most expensive ingredients becoming more efficient.
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    Comparison of the effects of oven- and microwave-roasting on the physicochemical properties and bioactive compounds of tomato seeds and oils
    (Wiley, 2023) Ozbek, Zeynep Aksoylu; Yildiz, Kivilcim; Ergonul, Pelin Gunc; Iyilikeden, Elif; Uzlasir, Turkan
    The tomato processing industry generates a significant amount of a by-product (pomace), which is a mixture of peels and seeds. The purpose of this study was to compare the effects of conventional oven-roasting (at 120 & DEG;C, 150 & DEG;C, and 180 & DEG;C for 25 min) and innovative microwave-roasting (at 240, 388, and 536 W for 3 min) pretreatments on the physicochemical properties, fatty acid profiles, bioactive contents, and aroma profiles of tomato seeds and their hexane-extracted oils. The total flavonoids contents (TFCs) of the seeds decreased from 258.40 to 141.20 mg quercetin equivalent (QE) per kg after roasting. All roasting treatments improved the extractability of both & alpha;- and & gamma;-tocopherols. The amounts of total tocopherols in the seeds increased from 917.61 to 1256.25 mg kg(-1) after pretreatment. Luteolin was found to be the most abundant phenolic in seed oils, increasing from 10.68 to 91.72 mg kg(-1), followed by quercetin, ferulic acid, and catechin. Within each roasting technique, the ones treated at 150 & DEG;C and 338 W yielded the oils with the highest concentrations of aroma compounds, 418 and 92 mg kg(-1), respectively. The detrimental effect of microwave-roasting on these compounds was more pronounced. In conclusion, microwave-roasting at shorter times than conventional roasting produced tomato seed oils with well-preserved bioactive components and few unfavorable changes.
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    Comparison of the effects of oven- and microwave-roasting on the physicochemical properties and bioactive compounds of tomato seeds and oils
    (Wiley, 2023) Ozbek, Zeynep Aksoylu; Yildiz, Kivilcim; Ergonul, Pelin Gunc; Iyilikeden, Elif; Uzlasir, Turkan
    The tomato processing industry generates a significant amount of a by-product (pomace), which is a mixture of peels and seeds. The purpose of this study was to compare the effects of conventional oven-roasting (at 120 & DEG;C, 150 & DEG;C, and 180 & DEG;C for 25 min) and innovative microwave-roasting (at 240, 388, and 536 W for 3 min) pretreatments on the physicochemical properties, fatty acid profiles, bioactive contents, and aroma profiles of tomato seeds and their hexane-extracted oils. The total flavonoids contents (TFCs) of the seeds decreased from 258.40 to 141.20 mg quercetin equivalent (QE) per kg after roasting. All roasting treatments improved the extractability of both & alpha;- and & gamma;-tocopherols. The amounts of total tocopherols in the seeds increased from 917.61 to 1256.25 mg kg(-1) after pretreatment. Luteolin was found to be the most abundant phenolic in seed oils, increasing from 10.68 to 91.72 mg kg(-1), followed by quercetin, ferulic acid, and catechin. Within each roasting technique, the ones treated at 150 & DEG;C and 338 W yielded the oils with the highest concentrations of aroma compounds, 418 and 92 mg kg(-1), respectively. The detrimental effect of microwave-roasting on these compounds was more pronounced. In conclusion, microwave-roasting at shorter times than conventional roasting produced tomato seed oils with well-preserved bioactive components and few unfavorable changes.
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    Effect of Salt Stress on the Phenolic Compounds, Antioxidant Capacity, Microbial Load, and In Vitro Bioaccessibility of Two Microalgae Species (Phaeodactylum tricornutum and Spirulina platensis)
    (Mdpi, 2023) Uzlasir, Turkan; Selli, Serkan; Kelebek, Haşim
    Microalgae have gained attention as alternative food sources due to their nutritional value and biological effects. This study investigated the effect of salt stress on the antioxidant activity, phenolic profile, bioavailability of bioactive compounds, and microbial counts in the blue-green algae Spirulina platensis and diatom species Phaeodactylum tricornutum. These microalgae were cultured in growth mediums with different salt concentrations (15-35 parts per thousand) We observed the highest antioxidant activity and phenolic compounds in the control groups. S. platensis (20 parts per thousand) exhibited higher antioxidant activity compared to P. tricornutum (30 parts per thousand), which decreased with increasing salt stress. Using HPLC-DAD-ESI-MS/MS, we identified and quantified 20 and 24 phenolic compounds in the P. tricornutum and S. platensis culture samples, respectively. The bioavailability of these compounds was assessed through in vitro digestion with the highest amounts observed in the intestinal phase. Salt stress negatively affected the synthesis of bioactive substances. Microbial counts ranged from 300 to 2.78 x 10(4) cfu/g for the total aerobic mesophilic bacteria and from 10 to 1.35 x 10(4) cfu/g for yeast/mold in P. tricornutum samples while the S. platensis samples had microbial counts from 300 to 1.9 x 10(4) cfu/g and the total aerobic mesophilic bacteria from 10 to 10(4) cfu/g, respectively. This study suggests that adding salt at different ratios to the nutrient media during the production of P. tricornutum and S. platensis can impact phenolic compounds, antioxidant capacity, microbial load evaluation, and in vitro bioaccessibility of the studied microalgae.
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    Impact of different salt concentrations on growth, biochemical composition and nutrition quality of Phaeodactylum tricornutum and Spirulina platensis
    (Elsevier Sci Ltd, 2023) Uzlasir, Turkan; Isik, Oya; Uslu, Leyla Hizarci; Selli, Serkan; Kelebek, Haşim
    The effects of different salt concentrations on the growth, aroma and quality parameters of P. tricornutum and S. platensis were investigated for the first time.Salt contents were 15, 25, 30 and 35%o for the P. tricornutum and 20, 25, 30 and 35%o for the S. platensis culture. Aroma compounds were analyzed by HS-SPME-GC/MS while the organic acid and sugar composition were studied by HPLC-PDA-RID.The main amino acids were glutamic acid (6.24-12.96 mg/100 g) and alanine (3.67-13.65 mg/100 g) while the prevailing sugars were sucrose (229-1099 mg/100 g) and glucose (192-2322 mg/100 g) in the P. tricornutum and S. platensis samples.The most prevailing aroma compound was acetic acid (113 & mu;g/kg) in the P. tricornutum samples and heptadecane (36941 & mu;g/kg) in the S. platensis samples.A significant reduction was found in the amount of aroma compounds, amino acids, sugars and organic acids with increasing salt concentration.The study results are valuable for producing highquality and flavorful P. tricornutum and S. platensis products.
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    LC-DAD-ESI-MS/MS characterization of elderberry flower (Sambucus nigra) phenolic compounds in ethanol, methanol, and aqueous extracts
    (Wiley, 2021) Uzlasir, Turkan; Kadiroglu, Pinar; Selli, Serkan; Kelebek, Haşim
    The aim of the present study is to elucidate the phenolic compositions and antioxidant properties of methanol, ethanol, and aqueous extracts of elderberry flower as well as their sugars, organic acids, and color properties. Phenolic compounds were analyzed with LC-DAD-ESI-MS/MS, while organic acids and sugars were analyzed with LC-DAD-RID. Aqueous extracts were found rich in phenolic compounds and the highest phenolic content was determined in infusions obtained at 100 degrees C for 30 min (922.26 mg/L), whereas the lowest was detected in the ethanol extract for 5 min (238.98 mg/L). Chlorogenic acid, 5-p-coumaroylquinic acid, dicaffeoylquinic acid, and quercetin-3-rutinoside were the most abundant phenolics in all of the extracts.The results revealed significant differences among aqueous, methanol, and ethanol extracts of elderberry flower regarding phenolics, antioxidant, and other chemical properties.Using water infusions at 100 degrees C for 5 and 30 min, respectively, resulted in a higher phenolic and antioxidant potential yield than from using other extractions. Practical Application Elderberry flowers posses a substantial supply of bioactive flavonoids, antioxidant, and phenolic compounds which have frequently been used in traditional medicine and healing. Different solvents and infusion times in extraction might induce differences in phenolic composition and bioactive features. This study highlights that the elderberry flower can be consumed as an alternative herbal tea which is rich in phenolic substances.
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    LC-DAD/ESI MS/MS characterization of fresh and cooked Capia and Aleppo red peppers (Capsicum annuumL.) phenolic profiles
    (Springer, 2020) Kelebek, Haşim; Sevindik, Onur; Uzlasir, Turkan; Selli, Serkan
    Peppers are one of the most widely processed and consumed vegetables in the world. The present study was established to obtain phenolic profiles of two fresh and oven-cooked pepper cultivars, red hot Aleppo (Capsicum annuumL.) and red sweet pepper Capia (Capsicum annuumL.). Phenolic extracts of pepper samples have been, for the first time, qualitatively and quantitatively examined by liquid chromatography including tandem mass spectrometry (LC-MS/MS). Apart from the main objective, samples were also examined for their colour alteration regarding the oven cooking process. A total of 20 phenolic compounds were identified and quantified in the red pepper samples. The revealed results showed that the hot Aleppo pepper possessed a much higher phenolic content when compared to Capia peppers. In the Aleppo pepper samples, capsaicin, luteolin 6,8-di-C-hexoside, luteolinO-malonylpentosyldihexoside, luteolin 6-C-hexoside, dihydrocapsaicin, and kaempferol pentosyldihexoside were the most dominant phenolics, while luteolinO-(aposylmalonyl)glucoside, luteolinO-malonylpentosyldihexoside, kaempferol pentosylhexoside, and feruloyl hexoside were for the Capia samples. In the Aleppo samples, capsaicin and dihydrocapsaicin were compounds that significantly increased due to the cooking process. The cooking process not only positively affected the phenolic profile of pepper samples but also the colour, total phenolic content, and antioxidant activity.
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    Optimization of complex coacervation parameters for the production of encapsulated black garlic using response surface methodology
    (Wiley, 2023) Sasmaz, Hatice Kubra; Adal, Eda; Kadiroglu, Pinar; Selli, Serkan; Uzlasir, Turkan; Kelebek, Haşim
    The purpose of this study was to optimize black garlic encapsulation parameters (core/coating ratio, extract concentration, and coacervate/maltodextrin [MD] ratio) using central composite design of the response surface methodology based on encapsulation efficiency (EE) (%). The optimum parameters were determined as 4.0 for the coating material/core ratio, 50% for the extract concentration, and 6.0 for the MD/coacervate ratio depending on the EE (%). The antioxidant activity values were determined as 101 and 134 mu mol Trolox/100 g dry weight (DW) for the 2,2-diphenyl-1-picrylhydrazyl and 2,2 '-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) methods, respectively, whereas the total phenolic content was 49 mg gallic acid equivalent/100 g DW for the encapsulated black garlic samples. S-Allyl-L-cysteine (SAC), gamma-L-glutamyl-SAC (GSAC), gamma-L-glutamyl-(S)-trans-1-propenyl-L-cysteine, and allicin were the organosulfur (OS) compounds determined in the samples. The SAC concentration of the encapsulated black garlic samples was determined as 22.36 mg/g, whereas the GSAC content was found at a lower concentration (0.33 mg/g) compared to SAC. The allicin content was quantified to be 0.31 mg/g. The encapsulated samples were also characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. The FT-IR analysis revealed specific functional groups, including hydroxyl, carbonyl, and glycosidic linkage. The interaction between lentil protein isolate and pectin was strong enough to encourage capsule formation as visualized in the SEM images. This study shows the potential of black garlic coacervates as a functional ingredient for the food industry due to their stability, solubility, and preservation of OS and antioxidant compounds.
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    Optimization of complex coacervation parameters for the production of encapsulated black garlic using response surface methodology
    (Wiley, 2023) Sasmaz, Hatice Kubra; Adal, Eda; Kadiroglu, Pinar; Selli, Serkan; Uzlasir, Turkan; Kelebek, Hasim
    The purpose of this study was to optimize black garlic encapsulation parameters (core/coating ratio, extract concentration, and coacervate/maltodextrin [MD] ratio) using central composite design of the response surface methodology based on encapsulation efficiency (EE) (%). The optimum parameters were determined as 4.0 for the coating material/core ratio, 50% for the extract concentration, and 6.0 for the MD/coacervate ratio depending on the EE (%). The antioxidant activity values were determined as 101 and 134 mu mol Trolox/100 g dry weight (DW) for the 2,2-diphenyl-1-picrylhydrazyl and 2,2 '-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) methods, respectively, whereas the total phenolic content was 49 mg gallic acid equivalent/100 g DW for the encapsulated black garlic samples. S-Allyl-L-cysteine (SAC), gamma-L-glutamyl-SAC (GSAC), gamma-L-glutamyl-(S)-trans-1-propenyl-L-cysteine, and allicin were the organosulfur (OS) compounds determined in the samples. The SAC concentration of the encapsulated black garlic samples was determined as 22.36 mg/g, whereas the GSAC content was found at a lower concentration (0.33 mg/g) compared to SAC. The allicin content was quantified to be 0.31 mg/g. The encapsulated samples were also characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. The FT-IR analysis revealed specific functional groups, including hydroxyl, carbonyl, and glycosidic linkage. The interaction between lentil protein isolate and pectin was strong enough to encourage capsule formation as visualized in the SEM images. This study shows the potential of black garlic coacervates as a functional ingredient for the food industry due to their stability, solubility, and preservation of OS and antioxidant compounds.
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    Targeted analysis for the detection of phenolics and authentication of Albanian wines using LC-DAD/ESI-MS/MS combined with chemometric tools
    (Cell Press, 2024) Topi, Dritan; Topi, Ardiana; Güçlü, Gamze; Selli, Serkan; Uzlasir, Turkan; Kelebek, Haşim
    In recent years, Albania has seen a significant increase in wine production, which can be attributed to the growing interest in the diversity of native grape varieties. Among the most popular grape varieties are Kallmet, Shesh i zi (ShiZ), Shesh i bardhe (ShiB), and Cerruje, which are known for their distinctive wines as well as the planted area. A study was conducted to investigate the influence of the territory and vintage on phenolic compounds of single-variety wines from these grape varieties. Liquid chromatography identified and quantified thirty-one phenolic compounds, sub-grouped into flavonoids and non-flavonoids, with diode-array detection coupled to electrospray ionization tandem mass spectrometry (LC-DAD-ESI/MSn). Within the red wines group, the ShiZ variety wine presented the highest phenolic content (1037 mg/L), followed by Kallmet cv. (539 mg/L); conversely, in the white wine group, the ShiB wines (699 mg/L) were distinguished from the Cerruje variety. Gallic acid was the main phenolic compound, followed by procyanidin B3. ShiB and ShiZ had the highest levels, at 215 and 136 mg/L, respectively. Among flavanols, (+)-catechin was found in the highest levels, with the maximum in Kallmet cv. red wine (58.9 mg/L), followed by (-)-epicatechin (29.1 mg/L). The ShiB wine had the highest content of flavonols, with quercetin-3-O-glucuronide and quercetin-3-O-glucoside as the main contributors. The highest quantity of stilbenoids belonged to Kallmet red wine (1.59 mg/L). Applying Principal Component Analysis (PCA) in red and white wine groups made a good separation possible according to variety and region. However, a separation according to vintage year was not successful.