Oblikovanje jestivih filmova iz proteina soje unakrsnim vezivanjem transglutaminazom iz bakterije Streptomyces

Soybean protein isolate (SPI) was used in the investigation of the formation of edible protein films through an enzymatic cross-linking method with a purified microbial transglutaminase (MTG) produced from a new effective strain Streptomyces sp. WZFF.L-M1 preserved in our laboratory, followed by the addition of glycerol and suitable heating and drying treatments. Cheaper partially-purified skimmed soybean protein powder (SSP) and whey protein isolates (WPI) were used as the substitutes partially replacing the expensive SPI products, and purified β-lactoglobulin was taken as the positive control of WPI. As a result, the three alternatives could also form highly efficient edible films under the optimal operation conditions. The films made with SPI alternatives, about 50 µm thin, had homogenous network structures, without any holes by direct observation with the naked eye. The tests of the properties of these films showed that they had high water-keeping capacity and strong elasticity, that the ultimate tensile strength (TS) and the elongation at break (Eb) had been remarkably increased (TS>5 MPa, Eb>50 %), and that the prevention rates against the permeability of water vapour and oxygen in the air were also upgraded more than 85 and 70 %, respectively.Izolat proteina soje upotrijebljen je pri oblikovanju jestivih filmova metodom unakrsnog vezivanja transglutaminaze iz novoga soja bakterije Streptomyces sp. WZFF.L-M1, uzgojenog u našem laboratoriju. Nakon dodavanja glicerola, film je zagrijan te osušen. Dio skupih izolata proteina soje zamijenjen je jeftinijim, djelomično pročišćenim obranim prahom proteina soje i izolatima proteina surutke, a pročišćenim β-laktoglobulinom dokazana je prisutnost izolata proteina surutke. Rezultati su pokazali da se u optimalnim uvjetima, upotrebom triju zamjenskih izolata, mogu proizvesti vrlo učinkoviti jestivi filmovi. Struktura filmova debljine oko 50 µm, dobivenih uporabom zamjenskih izolata, bila je homogena, bez okom vidljivih rupica. Rezultati ispitivanja pokazali su veliku moć zadržavanja vode i elastičnost tih filmova. Znatno je povećana granična čvrstoća (>5 MPa) i istezljivost (>50 %) te smanjena njihova propusnost na vodenu paru za 85 % i kisika za 70 %

Oblikovanje jestivih filmova iz proteina soje unakrsnim vezivanjem transglutaminazom iz bakterije Streptomyces

Soybean protein isolate (SPI) was used in the investigation of the formation of edible protein films through an enzymatic cross-linking method with a purified microbial transglutaminase (MTG) produced from a new effective strain Streptomyces sp. WZFF.L-M1 preserved in our laboratory, followed by the addition of glycerol and suitable heating and drying treatments. Cheaper partially-purified skimmed soybean protein powder (SSP) and whey protein isolates (WPI) were used as the substitutes partially replacing the expensive SPI products, and purified β-lactoglobulin was taken as the positive control of WPI. As a result, the three alternatives could also form highly efficient edible films under the optimal operation conditions. The films made with SPI alternatives, about 50 µm thin, had homogenous network structures, without any holes by direct observation with the naked eye. The tests of the properties of these films showed that they had high water-keeping capacity and strong elasticity, that the ultimate tensile strength (TS) and the elongation at break (Eb) had been remarkably increased (TS>5 MPa, Eb>50 %), and that the prevention rates against the permeability of water vapour and oxygen in the air were also upgraded more than 85 and 70 %, respectively.Izolat proteina soje upotrijebljen je pri oblikovanju jestivih filmova metodom unakrsnog vezivanja transglutaminaze iz novoga soja bakterije Streptomyces sp. WZFF.L-M1, uzgojenog u našem laboratoriju. Nakon dodavanja glicerola, film je zagrijan te osušen. Dio skupih izolata proteina soje zamijenjen je jeftinijim, djelomično pročišćenim obranim prahom proteina soje i izolatima proteina surutke, a pročišćenim β-laktoglobulinom dokazana je prisutnost izolata proteina surutke. Rezultati su pokazali da se u optimalnim uvjetima, upotrebom triju zamjenskih izolata, mogu proizvesti vrlo učinkoviti jestivi filmovi. Struktura filmova debljine oko 50 µm, dobivenih uporabom zamjenskih izolata, bila je homogena, bez okom vidljivih rupica. Rezultati ispitivanja pokazali su veliku moć zadržavanja vode i elastičnost tih filmova. Znatno je povećana granična čvrstoća (>5 MPa) i istezljivost (>50 %) te smanjena njihova propusnost na vodenu paru za 85 % i kisika za 70 %

Inclusive K0SK0S resonance production in electron-proton collisions at HERA

At the HERA particle accelerator, 27.5 GeV electrons collide with 920 GeV protons. Photoproduction events, in which the quasi real photon emitted from the electron interacts with the proton with small momentum transfer, are dominant by 90% of the data sample. K0S-K0S candidate pairs, which might couple to glueballs, are selected and studied with the ZEUS detector in the photon-proton center-of-mass range 130 GeV < W_gamma_p < 270 GeV using the entire data luminosity of 0.5 fb^-1. Enhancements attributed to the production of f2(1270)/a02(1320), f'2(1525) and f0(1710) are observed in the K0S-K0S invariant mass spectrum. A coherent fit, which has taken into account the interference effects by SU(3) symmetry argument, provides precise measurement values on mass and width of the states. It gives a five standard deviation enhancement on state f0(1710) in terms of statistical significance. This is by far the best measurement in e-p collision experiments, and is consistent with results from other experiments and the world averages. Furthermore, spin analysis on the glueball candidate f0(1710) are performed as an approach to reveal the glueball content of the meson state. However, due to the complicated background condition, the angular distribution method and the partial wave analysis are undetermined and fail to give a positive result on the spin.À l'accélérateur de particules HERA, des électrons de 27.5 GeV entrent en collision avec des protons de 920 GeV. Les événements de photoproduction, où le photon émis par l'électron est quasi-réel et interagit avec le proton avec un petit échange de quantité de mouvement, dominent l'échantillon de données. Les paires K0S-K0S, susceptibles de se coupler aux boules de gluons ("glueballs"), sont choisies et étudiées avec le détecteur ZEUS dans un domaine d'énergie du centre de masse photon-proton entre 130 GeV et 270 GeV en utilisant la luminosité complète de 0.5 fb^-1 des données. Des structures observées dans le spectre de masse invariante K0S-K0S sont attribuées aux états f2(1270)/a02(1320), f'2(1525) et f0(1710). Une procédure d'ajustement de fonctions cohérentes, qui tient compte des effets d'interférence de par un argument de symmétrie SU(3), procure des valeurs mesurées précises de masse et de largeur de signal pour ces états. En terme de signification statistique, une déviation par cinq sigmas est obtenue pour l'état f0(1710), ce qui est de loin le meilleur résultat dans des expériences aux collisions e-p et est consistant avec les résultats d'autres expériences et les moyennes mondiales. De plus, une analyse de spin est effectuée sur le candidat "glueball" f0(1710) dans une tentative de déduire le contenu "glueball" de cet état mésonique. Toutesfois, À cause des conditions sévères du bruit de fond, les méthodes de distributions angulaires et d'analyse d'ondes partielles ne peuvent parvenir à donner un résultat positif sur la valeur du spin

Effects of Huge Earthquakes on Earth Rotation and the length of Day

We calculated the co-seismic Earth rotation changes for several typical great earthquakes since 1960 based on Dahlen¡¦s analytical expression of Earth inertia moment change, the excitation functions of polar motion and, variation in the length of a day (ΔLOD). Then, we derived a mathematical relation between polar motion and earthquake parameters, to prove that the amplitude of polar motion is independent of longitude. Because the analytical expression of Dahlen¡¦s theory is useful to theoretically estimate rotation changes by earthquakes having different seismic parameters, we show results for polar motion and ΔLOD for various types of earthquakes in a comprehensive manner. The modeled results show that the seismic effect on the Earth¡¦s rotation decreases gradually with increased latitude if other parameters are unchanged. The Earth¡¦s rotational change is symmetrical for a 45° dip angle and the maximum changes appear at the equator and poles. Earthquakes at a medium dip angle and low latitudes produce large rotation changes. As an example, we calculate the polar motion and ΔLOD caused by the 2011 Tohoku-Oki Earthquake using two different fault models. Results show that a fine slip fault model is useful to compute co-seismic Earth rotation change. The obtained results indicate Dahlen¡¦s method gives good approximations for computation of co-seismic rotation changes, but there are some differences if one considers detailed fault slip distributions. Finally we analyze and discuss the co-seismic Earth rotation change signal using GRACE data, showing that such a signal is hard to be detected at present, but it might be detected under some conditions. Numerical results of this study will serve as a good indicator to check if satellite observations such as GRACE can detect a seismic rotation change when a great earthquake occur