Chitosan and chitooligosaccharides were extracted from white-leg shrimp shells by chemical treatment. Low molecular weight (13 kDa) and a high degree of deacetylation (54.83%) in chitooligosaccharides led to high water solubility compared to chitosan. Antimicrobial assays indicated that chitosan and chitooligosaccharides exhibited marked inhibitory activity against food-borne pathogenics, spoilage bacterial, and fungal strains tested. However, chitooligosaccharides revealed greater inhibitory effects than chitosan on tested microorganisms. The substitution of flour by chitosan or chitooligosaccharides in bread formulation (1 g/100 g total weight basis) showed antimicrobial effects against and sp. growth. Also, the fruity odor in bread containing chitosan or chitooligosaccharides was delayed. Interestingly, the bread containing chitooligosaccharides showed a stronger inhibitory effect against and sp. compared to bread containing chitosan and control, where and sp. were observed growing on the surface of bread after 4 days of incubation at 30 °C.

Gluten-free bread formulations based on small broken rice berry using various types of hydrocolloids (xanthan gum, guar gum, and locust bean gum) at different concentrations (0, 1, 1.5, and 2 g/100 g) were tested in this study. The effects of hydrocolloid addition on the pasting properties of flour were also investigated, including the quality parameters of the breads. The pasting properties of small broken rice berry flour incorporated with guar gum were most affected. Gluten-free bread containing hydrocolloid showed improved qualities in terms of loaf specific volume, texture, sensory values, and microstructure. A 1 g/100 g of hydrocolloid addition was sufficient to improve the physical and chemical qualities of bread. The highest score of all attributes from the sensory evaluation was obtained by gluten-free bread containing 1 g/100 g guar gum.

Extraction of hyaluronan from animals or microbial fermentation has risks including contamination with pathogens and microbial toxins. In this work, tobacco cultured-cells (BY-2) were successfully transformed with a chloroviral hyaluronan synthase (cvHAS) gene to produce hyaluronan. Cytological studies revealed accumulation of HA on the cells, and also in subcellular fractions (protoplasts, miniplasts, vacuoplasts, and vacuoles). Transgenic BY-2 cells harboring a vSPO-cvHAS construct containing the vacuolar targeting signal of sporamin connected to the N-terminus of cvHAS accumulated significant amounts of HA in vacuoles. These results suggested that cvHAS successfully functions on the vacuolar membrane and synthesizes/transports HA into vacuoles. Efficient synthesis of HA using this system provides a new method for practical production of HA.

The aim of this study was to develop gluten-free bread formulations based on small broken riceberry flour, by using different ratios of rice flour and xanthan gum. Small broken riceberry and rice flour could be classified as low in amylose content (15.70 g and 20.50 g/100 g dry matter for small broken riceberry and rice flour, respectively). Additionally, small broken riceberry flour contained a total phenolic and total anthocyanin content approximately 500 times higher than that of rice flour. The addition of increased amounts of small broken riceberry flour and xanthan gum resulted in darker coloured gluten-free bread. However, there was no significant difference regarding moisture and specific volume. The increase of small broken riceberry flour and xanthan gum also led to a significant increase in the firmness of bread crumbs. The sensory evaluation showed differences in flavour, texture and overall liking, since adding small broken riceberry flour tended to make gluten-free bread more favourable. Bread containing rice flour and small broken riceberry flour in the ratio of 30:70 and 1.0% xanthan gum was selected on the basis of the sensory quality. Moreover, such bread also contained high levels of total phenolic and anthocyanin content.

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