Nurzat ŞAYKİYEVA | Mirlan MOLDOBAYEV | Kubat KEMELOV | Canıl İSKAKOVA | Mustafa DOLAZ

Article | 2023 | Starch-Starke75 ( 9-10 )

Kyrgyzstan is a landlocked country in Central Asia, famous for its crystal-clear lakes, majestic Tien Shan Mountains that bisect the territory of Turkistan, and magnificent natural beauty. This study aims to evaluate the fruit (acorns) of the oak trees (Quercus robur L.) grown in Bishkek, the capital city of Kyrgyzstan. For this purpose, carboxymethyl acorn starch (CMAS), which is not synthesized in literature, is first synthesized by isolating acorn starch (AS) from the acorns. The structures of CMASs are characterized by H-1(C-13)-NMR, FT-IR, XRD, and SEM techniques. The viscosities of the samples with different degrees of substit . . .ution (DS), such as 0.62, 0.95, and 1.01, determined by the titrimetric method, are measured as 247, 600, and 388 mPa s, respectively. In addition, considering the film-forming properties of CMASs, tomatoes are coated, and their shelf lives are investigated. Weight loss (WL) is 38.36 in control and 25.52 in coated tomato after 4 weeks. The needle penetration depth is measured as 388 mm in the control and 249 mm in the coated tomato. Total soluble solids (TSS) content showed approximate results in both samples. Control tomatoes containing 78.8 mg 100 g(-1) ascorbic acid lost significantly during storage, reducing to 13.90 mg 100 g(-1). Keyword: acorn starch; carboxymethylation; NMR; storage qualit More less

Mustafa DOLAZ

Article | 2022 | Starch-Starke8 ( 9 )

Two new Schiff bases ligands (HL1 and HL2) and their Co2, Mn2, Fe3, Ru3, Cr3, and VO2 complexes were synthesized and characterized by FT-IR, 1H-NMR, and Mass spect. and analytical methods. A single-crystal X-ray diffraction study determined the molecular structure of HL1. The catalytic effects of metal complexes on benzyl alcohol and potato starch (PS) oxidation were compared in an H-2O-2 medium. The percent conversion of benzyl alcohol to benzaldehyde and benzoic acid was determined by Gas Chromatography. [Co(L-1)(2)], [Mn(L-1)(2)], [Co(L-2)(2)], and [Mn(L-2)(2)] showed the highest catalytic effect with a value between 97-98 in the . . . conversion of benzyl alcohol to benzaldehyde and benzoic acid. Maximum benzoic acid formation was observed in [Mn(L-1)(2)] (39) and [VO(L-1)(2)] (58). To determine the effect of the catalyst properties of the complexes on the oxidation of PS, carbonyl and carboxyl groups formed in potato starch were determined by the titrimetric method, and PS oxidation degrees were calculated as DS (DSCHO and DSCOOH). In potato starch oxidation, the [VO(L-1)(2)] had the highest catalytic effect with DSSum 0.96, while the [Mn(L-1)(2)] had a relatively lower DSSum 0.86 value. On the other hand, the [Cr(L-2)(2)ClH2O] showed a catalytic impact with DSSum 0.63 More less