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This study explored the influence of germination and fortification on the functionality and digestibility of brown rice from the perspective of starch structure changes. The surface of germinated brown rice starch appeared some pits and holes under the action of endogenous hydrolase, and the amylose content, relative crystallinity and short-range order of the starch decreased significantly after germination. However, the fortification treatment seemed to intensify the enzymatic hydrolysis of germinated brown rice starch, showing deeper pits, lower short-range order and less double helix structure. These changes in structural characteristics led to a significant decrease in peak viscosity, enthalpy change (ΔH) and starch hydrolysis rate after germination and fortification treatment. As the germination time increased, the trend became more obvious. And the peak viscosity and enthalpy change (ΔH) of fortified brown rice reached the minimum values of 290.89 cP and 13.73 J/g after 34 h of germination, respectively, while the starch hydrolysis rate reached the maximum value of 85.42 %. Overall, the combination of germination and fortification could be an effective method to adjust the functional and digestive characteristics of starch by changing its structural characteristics.

In this work, the combination treatment of zinc sulfate fortification and germination was used to increase zinc content and bioavailability of brown rice. The zinc content in brown rice during germination time of 10-34 h gradually increased with the increase of zinc sulfate concentration (0-100 mg/L). Brown rice with zinc fortified concentration of 25 mg/L and germinated for 28 h was recommended, which reached the maximum (26.31%) of zinc bioavailability and met the requirements of recommended dietary intake (RDA) of zinc. The physicochemical and structural characteristics of brown rice under different treatment conditions were compared. As the germination time prolonged, the germination rate (%), total phenol content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging rate (%) and Gamma-aminobutyric acid content of fortified or unfortified brown rice increased, while the phytic acid content decreased. The fortification treatment improved total phenol content and antioxidant activity of germinated brown rice. The crystalline structure of brown rice was destroyed during germination, but no significant change of crystalline structure caused by zinc sulfate fortification was found. These results could provide valuable reference for the application of germination in the field of brown rice fortification and the preparation of zinc-rich germinated brown rice products.

The effect of pullulanase enzymatic hydrolysis time on the textural properties of acorn vermicelli was investigated by texture analyzer. And the influencing mechanism was revealed by exploring the physicochemical properties of acorn starch under the optimum enzymatic hydrolysis time by texture analyzer, scanning electron microscopy, X-ray diffraction and brabender viscograph. After acorn starch was hydrolyzed by pullulanase for 14 h, acorn vermicelli had excellent textural properties. In addition, the enzymatic hydrolysis transformed the acorn starch from spherical particles with smooth surface to polygonal particles with rough surface, as well as transformed the crystal structure of acorn starch from C-type to B-type. Compared with native acorn starch, enzyme hydrolyzed acorn starch had higher amylose content, better freeze-thaw stability, lower swelling power and, breakdown viscosity, stronger gel strength and, higher light transmittance. These excellent properties contributed to the exceptional textural properties and quality of acorn vermicelli. The results of this study may provide valuable information on the preparation of acorn vermicelli.

Our previous study based on the transcriptome profiling indicated that a fragment of α-crystallin type heat shock protein (α-Hsp) gene was one of the numerous cDNA sequences expressed differentially at various stages of head regeneration in Hydra vulgaris. To further investigate the role that which α-Hsp plays during hydra regeneration, a full-length cDNA of α-Hsp gene of H. vulgaris was isolated by the rapid amplification of cDNA ends (RACE) technique. The full-length cDNA of α-Hsp gene was 1156 bp, containing a 765 bp open-reading frame (ORF), which encodes a polypeptide of 254 amino acid residues with a molecular weight of 29.27 kDa. Further, the ORF was subcloned into the plasmid pET-42a(+), and the recombinant plasmid pET-42a(+)-α- Hsp was transformed to Escherichia coli BL21(DE3), then the fusion protein GST-α-Hsp was expressed mainly in the form of a soluble molecule after induction by isopropyl-β-d-thiogalactopyranoside. In addition, BALB/Cmice were immunized with the fusion protein to prepare the polyclonal antiserum which was used as the primary antibody for whole-mount immunohistochemical assay. The results from the immunohistochemical assay showed that α-Hsp had expressedmainly at the wound site and nearby area of hydra after decapitation operation, and both quantitative real-time polymerase chain reaction (qPCR) analysis and immunohistochemical assay revealed that the expression level of α-Hsp increased gradually during the early period of hydra regeneration, then reached a peak at 24 h after decapitation operation, while decreased during the late regeneration period. Moreover, it indicated an important role of α-Hsp gene in hydra head regeneration that RNA interference (RNAi)-mediated α-Hsp silencing led to the obvious delay of the regeneration of head structures in H. vulgaris. In conclusion, our results gave the hint that α-Hsp could be related to wound healing and tissue remodelling at early regeneration stages, and may lay the foundation for further studies about the physiological function and role of α-Hsp during hydra regeneration.

Our previous study based on the transcriptome profiling indicated that a fragment of α-crystallin type heat shock protein (α-Hsp) gene was one of the numerous cDNA sequences expressed differentially at various stages of head regeneration in

Cr release from stainless steels in different simulant fluids according to different test conditions is carried out with emphasis on ferritic stainless steels. Effects of Cr content and surface roughness on Cr release are discussed specially with a relation to corrosion resistant and passive film formation. Some primary results are attained: (1) higher Cr content means better corrosion resistance including higher potential and lower corrosion rate and less amount of Cr release from base metal; (2) decreasing surface roughness is in favor of the formation of passive film which can retrain Cr release from base metal effectively; (3) Cr content and surface roughness have synthetical effects on Cr release with a narrow innoxious field referring to surface roughness with decreasing Cr content in stainless steels.