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Physical and selected physicochemical properties of distilled water treated with low-temperature low-frequency glow plasma (LPGP) for 5, 15, 30, 45, 60 and 90 min are given. Particular properties of PTW non-linearly vary with the time of exposure to plasma. PTW is characterized as declusterized solution of normal water consisting of clathrates of excited, probably singlet oxygen molecules, inside the clathrates. PWT is free of hydrogen peroxide and ozone. Raman spectroscopy is the best tool for diagnostic assessment of PTW.

Generation of ZnS, CdS, CaS and MgS quantum dots (QDs) was attempted in the matrix of distarch phosphate, an anionic polysaccharide. Based on the analysis of FTIR spectra, thermograms and Differential Scanning Calorimetry, interactions of QDS with the matrix could be excluded. On generation of MgS QDs and also, to a certain extent, CaS QDs, hydrolysis of the salts generating these QDs took place. That process had an impact on the partial destruction of the matrix. Molecular weight and radii of gyration of the products showed that the generation of QDs was dependent on the properties of the matrix polysaccharide. The elasticity, plasticity and viscosity of the gels containing QDs were significantly lower than those of plain distarch phosphate. Generally these values changed with time similarly to gels free of QDs.

Summary:White, linearly polarized transformed starch amylopectin into amylose. Moreover, it activated α‐amylolysis of starch, hydrolysis of xylane with xylanase, hydrolyses of chitin with chitinase, chitosan with chitosanase, and, interestingly, influenced production of cyclodextrins with cyclodextrin glycosyltransferase. Effect of duration of illumination of cyclodextrin glucosyltransferase with polarized light had certain effect upon the yield and isomer ration of three isomeric cyclodextrins. Application of the polarized light required 1–2 hour illumination of the enzymes in a small reaction vessel followed by admixture of so activated enzymes to a bioreactor. Further reactions did not require any illumination.

Suspension (30 %, w/w) of corn starch (25 % amylose) in water was irradiated by UV-light with wavelength greater than 250 nm at 25°C, under a stream of nitrogen or air, for time intervals ranging from 5 to 25 h. Effects of the irradiation on the transition enthalpy and temperature for melting, and the pasting viscosity profile of the irradiated starch were examined. Weight-average molecular weight (Mw) and radius of gyration (Rg) of the irradiated starch molecules were measured by high performance size exclusion chromatography coupled with multiangle laser light scattering and differential refractive index detectors (HPSEC-MALLS-RI). In the case of starch irradiated under nitrogen, the transition enthalpy (ΔH) decreased with increasing irradiation time whereas the melting temperature was not changed. Similarly, the peak paste viscosity (Pv) decreased from 97 to 56 RVU by 25 h irradiation. Average Mw and Rg of amylopectin and amylose fractions, which were 93 × 10⁶ and 144 nm, and 2.0 × 10⁶ and 104 nm, respectively, were decreased by irradiation to 32.2 × 10⁶ and 93.7 nm, and 0.7 × 10⁶ and 83.6 nm by the irradiation for 15 h under nitrogen, respectively. When the starch was irradiated with aeration, sharp drops of all measured parameters were observed in 5 h of irradiation (ΔH 11.4 J/g, Pv 53.2 RVU, amylopectin Mw 50 × 10⁶). After 15 h under air, however, all measured values increased (ΔH 16.8 J/g, Pv 65.5 RVU, amylopectin Mw 63.1 × 10⁶). Molecular size distribution profiles confirmed oxidative the photodegradation in the early stage (up to 5 h), and cross-linking reactions in the late stage (5—15 h) of irradiation under aeration.

Weight-average molecular weight (Mw) and chain length of eight amylopectins isolated from one Australian, two United States, and five Korean wheats were measured using multiangle laser light scattering (MALLS) and refractive index (RI) detectors operated in a microbatch mode, and in a high-performance size-exclusion chromatography (HPSEC) mode. The Mwof amylopectins measured in the microbatch mode ranged from 29 × 106to 349 × 106. Three amylopectins (Geuru, Tapdong and WW) showed significantly high Mwvalues over 200 × 106. The Mwmeasured by HPSEC mode with MALLS-RI detectors (42 × 106to 73 × 106) were significantly less than those obtained in the microbatch mode with exception of dark northern spring hard wheat (DNS) amylopectin, indicating the possible variation of Mwby the analysis mode. Root-mean square of the radius of gyration (Rg) also was greater when the microbatch mode was used (122–340 vs. 95–116 nm). Chain length distributions of debranched amylopectins of different cultivars, measured by the HPSEC-MALLS-RI system, were similar. Weight average degrees of polymerization (DPw) of A, B1, and larger B chains (B=2) had ranges of 13–22, 26–46, and 58–73, respectively, and mass ratios of A and B chains ranged from 0.7 to 1.1.

Photochemical reactions of theophylline with primary and secondary alcohols in the presence of aliphatic ketones result in substitution of an a-hydroxyalkyl group for the hydrogen atom at C-8 position. The results indicate that both the a-hydroxyalkyl radicals derived by H-abstraction from alcohol and the ketyl radicals generated by photoreduction of ketone are involved in the reactions.