https://www.siftdesk.org/article-details/Transglutaminase-induced-gelation-properties-of-soy-protein-isolate-glycosylated-with-maltodextrin/445

Wheat is one of the most important cereal in the world, providing nutrients for humans and animals. The main objective of the present report is to summarize the knowledge about ß-glucan, one of the quality traits of wheat: ß-glucan. The ß-glucan, main component of dietary fibre, has many health benefits, such as immunomodulatory and cholesterol lower activity, faecal bulking effect, enhanced absorption of certain mineral, prebiotic effects, and reducing type II diabetes. The attention on food quality over quantity is growing in many part of the world so dietary fibre are gaining much interest. Compare to other component of the grain, dietary fibre have not been studied extensively. The present review describes the current status of knowledge about the genetic control of ß-glucan accumulation in wheat grain, and the gaps needed to be bridged for better understanding of the genetic architecture of this important trait.

Auricularia polytricha (A. polytricha) is a kind of edible fungus with high nutritional value, and melanin is one of its main active components. However, the research and application of melanin in A. polytricha has been neglected for a long time. The purpose of this study was to analyse the physicochemical properties of the melanin from A. polytricha and establish a cellulase-ultrasonic synergistic extraction process of A. polytricha melanin by orthogonal array and response surface design. Scanning electron microscopy (SEM), ultraviolet-visible spectroscopy (UV-Vis), infrared spectroscopy (IR), electron paramagnetic resonance spectroscopy (EPR) and elemental analysis were used to characterize the melanin. The stability and antioxidant activity of the melanin were also measured. The results showed that A. polytricha melanin is an eumelanin and displays a bulk amorphous morphology. The melanin had good stability in heat and light, and it also exhibited good antioxidant activity. The optimized extraction process of A. polytricha melanin was as follows: enzyme-to-substrate ratio (E/S) of 1.4%, enzymolysis temperature of 35°C, enzymolysis pH of 4.0, enzymolysis time of 80 min, NaOH concentration of 0.68 mol/L, solid-to-liquid ratio of 1:40 (g/mL), ultrasound power of 350 W, ultrasonic time of 62 min, and ultrasound temperature of 70°C. The results will be helpful for the efficient production of A. polytricha melanin and its application as a food colouring as well as antioxidant agent. Keywords: Auricularia polytricha, melanin, physicochemical properties, synergistic extraction

Insects could serve as an alternative amino acids source with less environmental impact and low production cost. In this study, phenylisothiocianate (PITC) pre–column derivatization and high-pressure liquid chromatographic (HPLC) method combined with solid phase extraction (SPE) was developed and used to quantify free amino acids present in American cockroach. Powdered cockroach sample were extracted in water at 90 oC for 20 min, pre-purified on silica-based cationic exchange (SCX) cartridges, derivatized and analyzed for the free amino acid compositions. The free amino acids derivatives were separated on Agilent Zorbax Extend-C18 (4.6 x 250 mm, 5 µm) HPLC column at 33 ± 0.1 oC with diode array detection (DAD) set at 254 nm. A total analysis time of 30 min was used to separate 15 amino acids including nine essential and six non-essential ones with gradient elution at a flow rate of 1.0 mL/min. The results showed linear calibration range from 50 to 150 pmol/uL for all the free amino acids. The sensitivity expressed as limits of quantification (LOQ) and limit of detection (LOD); repeatability and reproducibility precisions expressed as relative standard deviation (RSDs) percentages for all amino acids characterized by the following ranges:2.6 to 35.5 pmol/µL; 0.9 to 11.7 pmol/µL; 1.0 to 10.5 %; 6.8% to 51.9%. The optimized and validated analytical method was applied for the determination of free amino acids in American cockroach. The free amino acids concentrations ranged from His, 0.43 mg/g to Pro, 311.2 mg/g and the recovery ranged from Thr, 82.9 % to Glu and Gly, 100 %. The free amino acids concentrations were in the order Pro > Thr > Leu > Glu > Ile > Lys > Met > Val > Asp > Ser > Try > Gly > Arg > His. The concentration of Pro was 5 – 100 folds higher than other free amino acids and representing 50.64% of the total free amino acid. The free amino acids were found to constitute 61.5% of the total nutrients in Asmerican cockroach, indicating its promising source of amino acid and protein for food and feed. Keyword: Free amino acids, phenylisothiocianate, pre-column derivatization, limits of quantification, limit of detection, solid phase extraction.

The effects of heat and shear at various pH and salt concentrations on the denaturation of myofibrillar protein extracted from Humboldt squid (Dosidicus gigas) are investigated. Squid tissues subjected to heating and simultaneous heating and shear force treatments differ in the extent of myofibrillar protein conformational change and composition. Gel formation processes differ in these two treatments, as determined by the complex viscosity (h*) measurement and light-scattering technique. Low-field nuclear magnetic resonance spectroscopy suggests shear promotes hydrophobic patch exposure during the gelation process to generate a product with high water content and compact structure. Shear-treated products therefore have large T2 values with small proportions compared with untreated products. A comparison of gelation and protein crystal nucleation suggests that protein gelation is driven by hydrophobic interactions. Keywords: shear; myofibrillar protein gelation; Humboldt squid; structure; hydrophobic interactions