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Many parts of Musa balbisiana have been used widely in traditional medicine, food, or cosmetic purposes. The present study is aimed at obtaining the extract-enriching bioactive compounds from M. balbisiana and determining the bioactive activities of the extract. Total polyphenols and saponins in the extracts were quantified. The response surface method (RSM) was used to optimize the extraction with methanol support. The optimal extraction conditions were at 120 min in 65°C at the material/solvent ratio of 1/36 ( w / v ). The obtained extract containing 51.72 mg/gGAE of total polyphenols (TPC) and 41.66 mg/g of saponins (TSC) was evaluated for antioxidant, antibacterial, antifungal, and antidiabetic abilities. The extract of M. balbinasia fruit exhibited strong antioxidant activity. The IC50 112.57 μg/mL (DPPH) and 14.49 μg/mL (ABTS). The absorbance of the extract was 1.653 ± 0.030 at 250 ppm (RP assay). The antibacterial and antifungal inhibition exhibited a correlation with TPC and TSC. The extract inhibited Gram (+) S. aureus better than Gram (-) E. coli, while the inhibition percentage (I%) against A. flavus reached over 70% at 800 ppm. The IC50 value of the extract for anti-inflammatory activity was 187.91 μg/mL. The antidiabetic assessment revealed that methanolic extract showed quite strong inhibition with α-amylase (IC50 68.26 μg/mL) and α-glucosidase (IC50 72.61 μg/mL). The results of the study showed that M. balbinasia fruit is a potential source of bioactive phytochemicals, which can be used as a plant-based antioxidant, antibacterial, antifungal, anti-flammatorial, and antidiabetic agent. This is valuable information to support further studies to exploit and apply it in functional food, pharmaceutical, and cosmetic industries.

Introduction: Dosimetry is of crucial importance in radiation processing of food. Among others, plastic film has been widely used for dosimetry in radiation therapy since its density is quite similar to the equivalent biological materials. In this study, the depth dose distribution was estimated by using gafchromic film for the purpose of dosimetry in food irradiation. Experimental: The HD-V2 gafchromic dosimetry film was employed to measure the interested dose instead of ion chamber. A stack of 19 PMMA (polymethyl methacrylate) sheets interleaved with 20 pieces of gafchromic film was made. The phantom was applied in the low energy X-ray beams (maximum 100 keV) to obtain the depth dose profile. Results: A significant correlation between absorbed doses (D) and color level or optical density (O.D.) of irradiated dosimetry films was observed. The fitting function has the form of , where a, b, c are the parameters to be fitted. The depth dose distribution in the 30 mm thickness phantom was inferred from the calibration. Conclusion: The present method and the depth dose profile to be obtained are very meaningful in the processing of foodstuffs by radiation.

The photon - drag effect with electrons – acoustic phonon scattering in cylindrical quantum wire with an infinite potential is studied. With the appearance of the linearly polarized electromagnetic wave, the laser radiation field and the dc electric field, analytic expressions for the density of the direct current are calculated by the quantum kinetic equation. The dependence of the direct current density on the frequency of the laser radiation field, the frequency of the linearly polarized electromagnetic wave and the temperature of the system is obtained. The analytic expressions are numerically evaluated and plotted for a specific quantum wire, GaAs/AlGaAs. The difference of the density of the direct current in quantum wires from quantum well and bulk semiconductor is due to potential barrier and characteristic parameters of system. These results are for every temperature and are new results.

The light-effect in cylindrical quantum wire with an infinite potential for the case of electrons, optical phonon scattering, is studied based on the quantum kinetic equation. The density of the direct current in a cylindrical quantum wire by a linearly polarized electromagnetic wave, a DC electric field, and an intense laser field is calculated. Analytic expressions for the density of the direct current are studied as a function of the frequency of the laser radiation field, the frequency of the linearly polarized electromagnetic wave, the temperature of system, and the size of quantum wire. The density of the direct current in cylindrical quantum wire with an infinite potential for the case of electrons – optical phonon scattering is nonlinearly dependent on the frequency of the linearly polarized electromagnetic wave. The analytic expressions are numerically evaluated and plotted for a specific quantum wire, GaAs/GaAsAl., {"references":["H. Sigg, S. Graf, M. H. Kwakernaak, B. Margotte, D. Erni, P. Van Son, K. Kohler, Supperlattices Microstruct. Vol 19, pp. 105, 1996.","M. F. Kimmitt, C. R. Pidgeon, D. A. Jaroszynski, R. J. Bakker, A. F. G. Van Der Meer, and D. Oepts, \"infrared free electron laser measurement of the photon darg effect in P-Silicon\", Int. J. Infrared Millimeter Waves, vol 13, No 8, pp. 1065, 1992.","A. Grinberg and Luryi, \"Theory of the photon - drag effect in a two-dimensional electron gas\", Phys. Rev. B 38, pp. 87, 1988.","S. D. Ganichev, H. Ketterl, and W. Prettl, \"spin-dependent terahertz nonlinearities at inter-valance-band absorption in p-Ge\", Physica B 272, pp. 464-466, 1999.","N. Q. Bau, D. M. Hung and L. T. Hung, \"The influences of confined phonons on the nonlinear absorption coefficient of a strong electromagnetic wave by confined electrons in doping superlattices\", PIER Letters, Vol. 15, pp. 175-185, 2010.","V. L. Malevich Izv, \"High-frequency conductivity of semiconductors in a laser radiation field\", Radiophysics and quantum electronics, Vol. 20, Issue 1, pp. 98-101, 1977.","N. Q. Bau and D. M. Hung, \"Calculating of the nonlinear absorption coefficient of a strong electromagnetic wave by confined electrons in doping superlattices\", PIER B 25, pp. 39-52, 2010.","N. Q. Bau and B. D. Hoi, \"Influence of a strong electromagnetic wave (Laser radiation) on the Hall effect in quantum well with a parabolic potential\", J. Korean Phys. Soc, Vol. 60, pp. 59-64, 2012.","G. M. Shmelev, G. I. Tsurkan and É. M. Épshtein, \"Photostumilated radioelectrical transverse effect in semiconductors\", Phys. Stat. Sol. B, Vol. 109, pp. 53, 1982.\n[10]\tS. V. Kryuchkov, E. I. Kukhar' and E. S. Sivashova, \"Radioelectric effect in a superlattice under the action of an elliptically polarized electromagnetic wave\", Physics of the Solid State, Vol. 50, No. 6, pp. 1150-1156, 2008.\n[11]\tH. V. Ngoc, N. T. Huong, N. Q. Bau, \"The photon-drag effect in cylindrical quantum wire with a parabolic potential\", int. J. Vol. 54, No. 12, pp. 542-545, 2016. \n[12]\tN. V. Nhan, N. V. Nghia, N. V. Hieu, \"The dependence of a quantum acoustoelectric current on some qualities in a cylindrical quantum wire with an infinite potential GaAs?GaAsAl\", Materials Transactions, Vol. 56, No. 9, pp. 1408-1411, 2015."]}