Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
Browse
3 results
Search Results
Article Valorizing Sugar Industry Byproduct Through Microalga for Pigment Production(Springer, 2025) Engin, Iskin; Uzuner, SibelCurrently, consumers are seeking ways to obtain natural food colorants, and food supplements. Microalgal food colorants and supplements have become established in the food industry due to their ability to generate substantial biomass rich in polysaccharides, pigments, lipids, vitamins, and other bioactive compounds. However, the high costs associated with microalgal cultivation have gained interest in more economical alternatives. This study investigated the potential of using vinasse, a byproduct of the sugar industry, as a nutrient source to produce biomass, chlorophyll, and carotenoids with Parachlorella kessleri SAG211-11 h. The effects of culture conditions (vinasse concentration, light intensity and light/dark cycle) on chlorophyll a (Chl a), chlorophyll b (Chl b), and carotenoid content were investigated using Response Surface Methodology. The results showed that light intensity and light/dark cycle had a significant effect, especially on Chl a content (p < 0.05). Light intensity also showed a significant effect on Chl b and carotenoid content (p < 0.05). Response optimization was conducted under conditions of 5% vinasse concentration, 110 mu mol photons m(-2)s(-1), and 16:8 light dark cycle, yielding a Chl a content of 10.89 +/- 0.14 mg/L, Chl b content of 7.25 +/- 1.12 and carotenoid content of 2.79 +/- 0.94 mg/L. These results revealed that the chlorophyll content of P. kessleri cells can be enhanced under mixotrophic conditions by changing cultivation conditions with the usage of vinasse-based medium. Meanwhile, this research highlights vinasse as a sustainable carbon source for the cultivation of P. kessleri SAG211-11 h cells for chlorophyll and carotenoid production.Article Citation - WoS: 2Citation - Scopus: 2Enhanced Reducing Sugar Production and Extraction for Chlorella Vulgaris in Mixotrophic Cultivation Using High Hydrostatic Pressure Processing and Ultrasound(Taylor & Francis, 2023) Uzuner, Sibel; Kurhan, Şebnem; Akdemir Evrendilek, GülsünAlthough extraction of polysaccharides to convert reducing sugars (RS) from microalgae by acid or alkali pretreatments and enzymatic hydrolysis has been extensively studied, few reports exploring the use of high hydrostatic pressure processing (HHP) and ultrasonication (US) as emerging technologies for the extraction of sugars from microalgae biomass exist. Thus, the present study was conducted to determine the effects of mixotrophic growth and stress conditions (NaNO3 and CO2 concentration and light intensity) on RS and protein accumulation in the unicellular green alga Chlorella vulgaris in addition to optimization of the effectiveness of the sequential applications of HHP and US with dilute acid as well as simultaneous enzymatic saccharification on the production of RS from microalga cells. High light intensity, high CO2 concentration and limited nitrogen concentration promoted RS production. The maximum protein content (0.0683 mg g(-1)) was achieved at 0.3 g l(-1) NaNO3 concentration, 7000 mu mol photons m(-2) s(-1) and 6 l min(-1) CO2 concentration. The highest RS content of C. vulgaris after 48 h enzymatic saccharification (583.86 +/- 13.23 mg g(-1)) was obtained at 1% (w/w) acid concentration and 80% amplitude for 30 min with 79.4% RS yield. Combined US-assisted dilute acid pretreatment and enzymatic hydrolysis were also found to be more effective than HHP assisted dilute acid pretreatment and enzymatic saccharification. Therefore, microalgal biomass can be considered a suitable renewable feedstock used in fermentation. Highlights center dot The cultivation period of Chlorella vulgaris was reduced from 25 days to 14 days using mixotrophic growing conditions.center dot Mixotrophic conditions enhanced reducing sugar productivity.center dot Novel extraction techniques enhanced the extraction of reducing sugar from microalgae.Book Part Citation - Scopus: 1Enzyme Technology in Value Addition of Wine and Beer Processing(Elsevier, 2022) Uzuner, SibelSome endogeneous and exogeneous enzymes participate in the brewery and winery technologies. Industrial enzymes provide quantitative advantages (increased juice yields) and qualitative advantages (enhanced extraction and flavor) for processing (shorter maceration, settling, and filtration time). This review aims to explain the flow process of brewing and wine-making, discuss different enzymes used in brewery and wine-making industry. Also, this chapter summarizes the key enzymes used at different stages of wine-making and brewing, and the challenges of the exogeneous, commercial and immobilized enzymes. Finally, the use of immobilized enzymes is presented as a significant strategy to improve catalyst during brewing and wine-making.