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Gibberellic acid (GA3) is a tetracyclic diterpenoid carboxylic acid synthesized by the secondary metabolism of Fusarium fujikuroi. This phytohormone is widely studied due to the advantages it offers as a plant growth regulator, such as growth stimulation, senescence delay, flowering induction, increased fruit size, and defense against abiotic or biotic stress, which improve the quality and yield of crops. Therefore, GA3 has been considered as an innovative strategy to improve agricultural production. However, the yields obtained at large scale are insufficient for the current market demand. This low productivity is attributed to the lack of adequate parameters to optimize the fermentation process, as well as the complexity of its regulation. Therefore, this article describes the latest advances for potentializing the GA3 production process, including an analysis of its origins from crops, the benefits of its application, the related biosynthetic metabolism, the maximum yields achieved from production processes, and their association with genetic engineering techniques for GA3 producers. This work provides a new perspective on the critical points of the production process, in order to overcome the limits surrounding this modern line of bioengineering. [ABSTRACT FROM AUTHOR]

Nisin is a small peptide produced by Lactococcus lactis ssp lactis that is currently industrially produced. This preservative is often used for growth prevention of pathogenic bacteria contaminating the food products. However, the use of nisin as a food preservative is limited by its low production during fermentation. This low production is mainly attributed to the multitude of parameters influencing the fermentation progress such as bacterial cells activity, growth medium composition (namely carbon and nitrogen sources), pH, ionic strength, temperature, and aeration. This review article focuses on the main parameters that affect nisin production by Lactococcus lactis bacteria. Moreover, nisin applications as a food preservative and the main strategies generally used are also discussed. [ABSTRACT FROM AUTHOR]

Activation cross sections of proton induced nuclear reactions on palladium were measured up to 80 MeV by using the stacked foil irradiation technique and gamma ray spectrometry. The beam intensity, the incident energy and the energy degradation were controlled by a method based on flux constancy via normalization to the excitation functions of monitor reactions measured in parallel. Excitation functions for direct and cumulative cross-sections were measured for the production of 104 m,104 g,105 g,106 m,110 m Ag, 100,101 Pd, 99 m,99 g,100,101 m,101 g,102 m,102 g,105 Rh and 103,97 Ru radioisotopes. The cross section data were compared with the theoretical predictions of TENDL-2014 and -2015 libraries. For practical applications thick target yields were derived from the measured excitation functions. Application in the field of medical radionuclide production is shortly discussed. [ABSTRACT FROM AUTHOR]

Abstract: Excitation curves for reactions induced by proton beams up to 36MeV on highly enriched 116Cd targets were assessed. The standard stacked foil method, with monitoring of beam parameters over the whole energy region, and high resolution gamma spectrometry were used. We report cross sections for reactions leading to 113m ,114m,115m,116m1In and 115Cd. A comparison with some earlier experimental data and with results of theoretical model codes ALICE-IPPE and EMPIRE are presented. Our previous estimation of use of the 116Cd(p,3n) reaction for production of 114mIn is confirmed. [Copyright &y& Elsevier]

Abstract: The ALTO facility (Accélérateur Linéaire auprès du Tandem d’Orsay) has been built and is now under commissioning. The facility is intended for the production of low energy neutron-rich ion-beams by ISOL technique. This will open new perspectives in the study of nuclei very far from the valley of stability. Neutron-rich nuclei are produced by photofission in a thick uranium carbide target (UC x ) using a 10μA, 50MeV electron beam. The target is the same as that already had been used on the previous deuteron based fission ISOL setup (PARRNE []). The intended nominal fission rate is about 1011 fissions/s. We have studied the adequacy of a thick carbide uranium target to produce neutron-rich nuclei by photofission by means of Monte-Carlo simulations. We present the production rates in the target and after extraction and mass separation steps. The results from Monte-Carlo simulations are compared to experimental data either with the ALTO facility (in the first step of commissioning, i.e. 100nA of the electron beam current intensity), or with fast-neutron-induced fission generated from a 26MeV deuteron beam. The results obtained support the suitability of FLUKA simulation code used to describe all the photofission process with an electron beam energy of 50MeV. [Copyright &y& Elsevier]

The β+ emitter 83Sr (T1/2=32.4 h, Eβ+=1.23 MeV, Iβ+=24%) is a potentially useful radionuclide for therapy planning prior to the use of the β− emitter 89Sr (T1/2=50.5 d). In order to investigate its production possibility, cross section measurements on the 85Rb(p,xn)-reactions, leading to the formation of the isotopes 85m,gSr, 83Sr, 82Sr and 81Sr, were carried out using the stacked-foil technique. In a few cases, the products were separated via high-performance liquid chromatography. For 82Sr, both γ-ray and X-ray spectrometry were applied; in other cases only γ-ray spectrometry was used. From the measured excitation functions, the expected yields were calculated. For the energy range Ep=37→30 MeV the 83Sr yield amounts to 160 MBq/μA h and the level of the 85gSr (T1/2=64.9 d) and 82Sr (T1/2=25.5 d) impurities to <0.25%. In integral tests involving yield measurements radiostrontium was chemically separated and its radioactivity determined. The experimental production data agreed within 10% with those deduced from the excitation functions. The results of the 85Rb(p,3n)83Sr reaction were compared with the data on the production of 83Sr via the 82Kr(3He,2n)-process. In the energy range E3He=18→10 MeV the theoretical yield of 83Sr amounts to 5 MBq/μA h and the 82Sr impurity to about 0.2%. The method of choice for the production of 83Sr is thus the 85Rb(p,3n)-process, provided a 40 MeV cyclotron is available. During this study some supplementary information on the yield and purity of 82Sr was also obtained. [Copyright &y& Elsevier]