Loading...
3 results
Search Results
Now showing 1 - 3 of 3
- Bioactivity of honey: phenolic composition, antioxidant trends and carcinoma cell lines effects through digestionPublication . Mutlu, Ceren; Demir, Zeynep; Aylanc, Volkan; Özkan, Aysun; Erbaş, MustafaHoney is not only a food source but also a valuable substance for health and medicine, owing to its complex composition and bioactive properties. However, there is very limited information on the changes in the active compounds of honey during digestion and their antioxidant capacity and effect on cancer cells at the end of digestion. Herein, we investigate the dynamic changes in their bioactive compound composition and antioxidant activity during in vitro gastrointestinal digestion and the effect of digested honey on several cancer cell lines, after determining the antimicrobial and anti-inflammatory effects of mono- and multifloral kinds of honey. The tested raw honey samples exhibited higher anti-inflammatory properties (36 %–80 %) with increasing total phenolic content (78–132 mg GAE/100 g), along with significant antimicrobial activity against E. coli (6–9 mm) and S. aureus (6–14 mm) bacterial species. The findings showed that total phenolic and flavonoid contents increased significantly during digestion, with a peaking value of 258 mg GAE/100 g in the intestinal phase, while TEAC and CUPRAC analysis exhibited variable trends depending on the digestion stage. Moreover, the concentration of compounds such as gallic, syringic, caffeic, p-coumaric, trans-cinnamic acid, and methyl-3,4,5-trihydroxybenzoate identified by HPLC-DAD showed some fluctuations at different stages of digestion. Cyto-toxicity analysis revealed that digested honey samples, particularly those with higher phenolic content, exhibited pronounced antiproliferative effects on cancer cells at higher concentrations, with minimal effects on healthy cells. These findings underscore the importance of honey’s bioactive compounds, their transformation during digestion, and their potential health benefits.
- Optimisation of Catalytic Oxidation Conditions for the 2‐Keto‐L‐Gulonic Acid Production Using Response Surface MethodologyPublication . Mutlu, Ceren; Candal‐Uslu, Cihadiye; Erbaş, MustafaL-Ascorbic acid, also known as vitamin C, is a very important antioxidant ingredient situated many usage areas in different industries. 2-keto-L-gulonic acid (2-KLG) is the main precursor component of L-ascorbic acid production and it can be produced from L-sorbose via microbial fermentation or chemical (catalytic) oxidation. While some special strains are used in microbial fermentation, it is benefitted from some catalysts in chemical oxidation. Herein, it was aimed to determine the optimum reaction temperature, pH, and time conditions to produce maximum 2-KLG compound with the catalytic oxidation of L-sorbose in the presence of Pt/Al2O3 catalyst with response surface methodology approach. For this aim, the reaction temperature, pH, and time used as variable factors. The limit values of variable factors were applied as 40–60°C for the temperature, 7.00–9.00 for the pH value, and 3–9 h for the time. The analyses results demonstrated that the increasing temperature and time negatively effected the conversion of L-sorbose into the 2-KLG. The optimum conditions of variable factors were determined as 41.30 °C for the temperature, 8.23 for the pH, and 3.25 h for the reaction time by the central composite design. Under these optimum conditions, L-sorbose was converted into 2-KLG with an average yield of 43.70%.
- Bee bread: sorption isotherms, thermodynamic characteristics of moisture adsorption and evaluation of adsorbed waterPublication . Mutlu, CerenBee bread is a value-added apiculture product produced from bee pollen by mixed lactic acid fermentation. Although many studies focused on the bioactive components and health effects of the bee bread, there is no study concerned with understanding its moisture adsorption properties. Herein, it was aimed to evaluate moisture adsorption properties and thermodynamics of bee bread using different sorption models at 25 and 35 °C. The water adsorption of bee bread had Type II characteristics, and the monolayer moisture content was calculated with BET, GAB, and Caurie models between 3.58 and 5.80 g/100 g. The Peleg and Caurie models ensured better prediction for adsorption. The stability of bee bread was high at 25 °C according to the smaller ratio of Type III to Type II-bound water. The entropy of adsorption was 16.01–25.78 kJ/ mol.K and it decreased with the moisture adsorption. Besides, the moisture adsorption needs external energy from the environment because of ΔG > 0.