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Dissolution behavior and molecular conformation of waxy maize amylopectin in aqueous DMSO solutions containing different amounts of water and salts (NaCl or CaCl 2 up to 0.2 M) were characterized using multi-angle laser light scattering (MALLS; micro-batch mode) and dynamic light scattering (DLS) detectors. The solubility of amylopectin decreased and the molecular size measured increased when the water content in the DMSO increased, indicating that amylopectin chains tended to be less dissociated or aggregate by the excess amount of water. The amylopectin in aqueous DMSO solutions (10–50% water) had a spherical shape with a regular star structure, but the individual amylopectin chains were not affected by water content. Minor addition of salts facilitated the dissolution of amylopectin in aqueous DMSO solutions, possibly due to water cluster formation by the salt ions. However, a minute presence of salts (0.01 and 0.05 M) could induce the chain association even in 90% DMSO solution.

Amylosucrase (AS), maltooligosyltrehalose synthase (MTS), and maltooligosyltrehalose trehalohydrolase (MTH) were used in combined cross-linked enzyme aggregates (combi-CLEAs) to achieve one-step bioconversion of sucrose to trehalose. Combi-CLEAs of three enzymes were successfully established with acetone and glutaraldehyde (GA) as a precipitant and a cross-linker, respectively. The optimum enzyme ratio was 8:0.5:0.5 (AS, 4 mg:MTS, 0.25 mg:MTH, 0.25 mg). To improve trehalose production, bovine serum albumin was co-aggregated with enzymes as a proteic feeder. The trehalose production yield of combi-CLEAs was about 8% in each cycle on the basis of substrate added up to 400 mM. Finally, the combi-CLEAs used in this experiment showed reusability of about five cycles without any activity loss.

In this study, high molecular weight hyaluronic acid in powder form (HMW-HA, with average molecular weight of 1042 kDa) was degraded to low molecular (LMW-HA, 200–230 kDa) by several methods, and the changes in molecular structure and antioxidative activities brought about by each degradation method were compared. The degradation methods used were electron beam irradiation (EB), gamma ray irradiation (GM), microwave irradiation (MW), and thermal treatment (TH). The FT-IR spectra showed no substantial changes of the spectral pattern between HMW and LMW-HAs. However, the UV absorbance of LMW-HA by MW was considerably greater at 265 nm indicating the formation of more double bonds. The antioxidative activities of all LMW-HA samples were found to have risen, but the MW-treated LMW-HA showed the most significant increase due to a newly formed double bond. EB- and GM-treated LMW-HA showed the lowest polydispersity and little change in UV spectra from those of HMW-HA.

Puerarin, an isoflavone derived from kudzu roots, has strong biological activities. However, its bioavailability in vivo is often limited by its insolubility. A novel transglycosylase increases the solubility of puerarin >100-fold, by converting it to puerarin glycosides. Since over-consumption of an isoflavone might have toxic effects, therefore, we investigated the potential antimutagenic activity, bone marrow micronucleus test, and a 28-day oral repeated administration test with puerarin and its glycosides. In Ames tests, neither puerarin nor its glycosides exhibited mutagenic effects up to 200 μg/plate. Puerarin and its glycoside, glucosyl-α-(1,6)-puerarin, significantly reduced the mutagenic effect of 4-nitroquinoline-1-oxide by up to 41%. In bone marrow micronucleus tests using ICR mice, neither puerarin nor glucosyl-α-(1,6)-puerarin interfered with erythrocyte production in the bone marrow. Both compounds decreased the prevalence of polychromatic erythrocytes. Sprague–Dawley rats were orally dosed with puerarin and its glycosides daily for 28 days. Neither puerarin nor its glycosides caused significant alterations in histology, and biochemical and hematologic parameters. These results suggest that puerarin and its glycosides do not have significant toxic effects, at least in rodents, either in vitro or in vivo at doses of up to 250 mg/kg per day.

Hyaluronic acid (HA) is a linear high-molecular-weight polysaccharide with useful biomedical applications. Streptococcus zooepidemicus, a typical HA-producing bacterium, requires an animalderived nitrogen source such as tryptone, peptone or sheep blood as a nutrient. Sixteen nonanimal-derived (NAD) nitrogen sources were tested as a replacement for the expensive animalderived nitrogen sources, which may have safety issues. Among the sixteen tested NAD nitrogen sources, a yeast-derived nitrogen source (YE 0251) showed the highest HA productivity, which was equivalent to the control HA production medium containing tryptone in a 5-L jar and in 3,000-L industrial fermentations. In the 3,000-L fermentation, YE 0251 increased cell mass (dry cell weight) and HA production by 11% and 8%, respectively, compared with the control HA production medium. The final specific volumetric productivity (0.41 g/L • h) was improved by about 70% after reducing the fermentation time from 20 h to 12 h, compared to the conventional production medium.

Puerarin is an isoflavone derived from Kudzu roots and has antioxidant and hypocholesterolemic effects; however, its insolubility often limits its biological availability in vivo. Using a novel transglycosylation process, the solubility of puerarin glycosides was increased > 100-fold, but it was not known whether these modified puerarin glycosides maintained biological activities. We found that water-soluble puerarin glycosides fully maintained antioxidant activities compared with puerarin assessed by radical scavenging activity, reducing power assay, superoxide dismutase activity, and non-site-specific hydroxyl radical scavenging activity. Both puerarin and its glycosides also significantly reduced low-density lipoprotein (LDL) oxidation. Mice fed with puerarin glycosides (0.1% w/w) showed significantly reduced plasma total cholesterol levels, thus, we further investigated their hypocholesterolemic mechanisms by assessing several key gene expressions both in vitro and in vivo. Puerarin and its glycosides induced multiple changes in hepatic cholesterol metabolism. The LDL receptor promoter activity was increased dose-dependently in puerarin glycosides-treated HepG2 cells. Accordingly, the expression of LDL receptor mRNA and protein were also significantly increased in HepG2 cells and mouse livers. The transcription and translation of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase were down-regulated both in vitro and in vivo. The cholesterol 7α-hydroxylase (CYP7A1) mRNA levels were not affected in vitro but significantly up-regulated in the mouse livers. Collectively, our results show that puerarin and its glycosides are biologically fully active isoflavone and have antioxidant and hypocholesterolemic effects in HepG2 cells and in C57BL/6J mice. In the livers, hypocholesterolemic effects of puerarin glycoside may be achieved by multiple mechanisms including increasing LDL uptake, reducing cholesterol biosynthesis, and possibly enhancing cholesterol degradation.

To make starch/polycaprolactone (PCL) blend with high miscibility, starch was chlorinated (starch-Cl) by using methanesulfonylchloride (CH3SO2Cl) in dimethylformamide (DMF) prior to blending. Starch-Cl/PCL blends were prepared by the mixing between starch-Cl and PCL solutions under various conditions. To study the change of structure, thermal and physical characteristics of starch-Cl/PCL blend, FTIR, DSC, SEM, and solvent resistance were measured. By blending starch-Cl and PCL, a chemical reaction occurred partially in blend (FTIR result); thereby, the miscibility (DSC and SEM results) and solvent resistance were increased. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1716–1723, 2004

Disaccharide glycosides synthesised from food grade resources consist of the hydrophilic head group of maltose or lactose and provide better hydrophilic–lipophilic balance (HLB ¼ 12) to the long alkyl chain derived from palm oil (PO) and palm kernel oil (PKO). Maltoside provides more flexibility in the vesicle’s membrane because of its low packing density in the bilayer membrane compared to lactoside. The bending of the molecular structure in maltose form a less compact assembly for maltoside, whereas lactose is more linear in shape. Apart from hydrophilic moieties, packing behaviour was also governed by the hydrophobic moieties. PO has higher degree of unsaturation compared to PKO, thus providing higher fluidity in the bilayer membrane. Vesicle with high membrane flexibility is easier to disintegrate and deform to enhance drug penetration into the skin. Results showed that the glycosides delivered vitamin E (VE) into deeper skin layer at least two-fold higher than free VE.