Utilization of bacterial cellulose in food

Bacterial cellulose (BC) produced by some microorganisms has been widely accepted as a multifunctional nano-biomaterial. It is composed of linear glucan molecules attached with hydrogen bonds, which appears similar to plant cellulose. However, when compared with other conventional natural or synthesized counterparts, BC performs better in areas such as biomedicine, functional devices, water treatment, nanofillers, etc. for its distinct superior chemical purity, crystallinity, biocompatibility, and ultrafine network architecture. When BC is incorporated in a material or used as a scaffold, novel features result that are related to BC’s intrinsic characteristics mentioned above. This review mainly summarizes the recent developments of the functional products fabricated with BC. Besides, the controllable cultivation conditions should also be discussed for expecting to make a breakthrough in its productivity. We highlight the literatures mainly in last 5 years, exerting ourselves to provide the state-of-the-art opinions in areas wherever are focused on for BC researching.

Recent advances in bacterial cellulose

The pathology of type 2 diabetes is complex, with multiple stages culminating in a functional β-cell mass that is insufficient to meet the body's needs. Although the broad outlines of the disease etiology are known, many critical questions remain to be answered before next-generation therapeutics can be developed. In order to further elucidate the pathobiology of this disease, animal models mimicking the pathology of human type 2 diabetes are of great value. One example of a type 2 diabetes animal model is the high-fat diet-fed, streptozotocin (HFD/STZ)-treated rat model. The present review first summarizes the current understanding of the metabolic profile and pathology involved in the different stages of the type 2 diabetes disease progression in humans. Second, the known characteristics of the HFD/STZ rat model are reviewed and compared with the pathophysiology of human type 2 diabetes. Next, the suitability of the HFD/STZ model as a model of type 2 diabetes with a focus on identifying critical caveats and unanswered questions about the model is discussed. The improved understanding of refined animal models will hopefully lead to more relevant preclinical studies and development of improved therapeutics for diabetes. Depending on the amount of residual functional β-cells mass, the HFD/STZ rat model might be a suitable animal model of the final stage of type 2 diabetes.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/jdi.12235

Modeling type 2 diabetes in rats using high fat diet and streptozotocin

The functional and nutritional aspects of hydrocolloids in foods

Advances in biomedical and pharmaceutical applications of functional bacterial cellulose-based nanocomposites

Antidiabetic effects of Artemisia sphaerocephala Krasch. gum, a novel food additive in China, on streptozotocin-induced type 2 diabetic rats.

Bacterial cellulose (BC) is a new biomaterial which has wide application potential in various industries. BC industrialization requires bacterial strains with high BC productivity. The objective of this study is to increase the BC yield of a Gluconoacetobacter xylinus strain through mutagenesis induced by high hydrostatic pressure (HHP) treatment. In this study, the parental strain in its exponential phase was treated at 250 MPa and 25 °C for 15 min to induce mutagenesis using a HHP machine. The HHP-treated strains were incubated in glucose agar plate at 30 °C for 4 days. After the incubation, 50 larger colonies in these plates were randomly selected and cultivated to produce BC membrane in a tailor-made glass vessel, and wet weights of the BC membranes were tested. Compared with the parental strain, 29 mutants showed higher BC yields, of which eight mutants with BC yield >130.00 g/L were initially screened and were then cultivated for five generations to test their genetic stabilities for BC production. Among the eight mutants, M438, a mutant which showed the highest average BC yield (158.56 g/L) and lowest coefficient of variation (2.4%) for five generations, was finally screened as objective mutant. HHP treatment can serve as an effective method to cause mutagenesis in BC-producing bacteria. The HHP-treated strains with significantly higher BC yield than parental strain can be screened from the HHP-induced mutants.

Mutagenesis induced by high hydrostatic pressure treatment: a useful method to improve the bacterial cellulose yield of a Gluconoacetobacter xylinus strain

Antioxidant effects of Artemis sphaerocephala Krasch. gum, on streptozotocin-induced type 2 diabetic rats

Active-chlorine-mediated oxidation of 5-fluorouracil on a hierarchically ordered macroporous RuO2 electrode.

Fatty acid photodecarboxylase is a newly identified blue-light driven photoenzyme that catalyzes decarboxylation of fatty acids. The catalytic reaction involves a transient anionic semiquinone of flavin cofactor (FAD•-) as an intermediate, but photochemical properties of this anionic radical are largely unknown. Here, we have anaerobically produced the wild-type FAP in the FAD•- state and conducted femtosecond-resolved fluorescence and absorption measurements. We have observed the multiphasic deactivation dynamics of excited states on multiple time scales from a few picoseconds even to a few nanoseconds through conical intersections between various electronic states. Interestingly, the nanosecond components can only be observed from higher electronic excited states. Our results show the complexity of the energy landscapes of various excited states and rule out the occurrence of electron or proton transfer with nearby residue(s) in the active site.

Rui-Qin Wu

Papers

Antidiabetic effects of Artemisia sphaerocephala Krasch. gum, a novel food additive in China, on streptozotocin-induced type 2 diabetic rats.

Mutagenesis induced by high hydrostatic pressure treatment: a useful method to improve the bacterial cellulose yield of a Gluconoacetobacter xylinus strain

Antioxidant effects of Artemis sphaerocephala Krasch. gum, on streptozotocin-induced type 2 diabetic rats

Active-chlorine-mediated oxidation of 5-fluorouracil on a hierarchically ordered macroporous RuO2 electrode.

Ultrafast Dynamics of Fatty Acid Photodecarboxylase in Anionic Semiquinone State.