Effect of gamma irradiation on microbiological and nutritional properties of the freeze-dried berries

Lyophilization or freeze-drying is the technique of removing ice or other frozen solvents from a material through sublimation and the removal of bound water molecules through the process of desorption. Drying occurs in an absolute vacuum at temperatures from −40°C to −50°C. This technique is often used for the conservation of fruits, especially berries. During this process, the water changes from frozen to gaseous, with no thawing. Due to low temperatures and the high vacuum, most microorganisms are rendered inactive during the lyophilization process. However, if there is a necessity to destroy all microorganisms from treated food, subsequent irradiation with gamma rays is an appropriate method. This paper investigated the influence of different doses of gamma radiation on lyophilized berries’ microbiological characteristics. It was shown that the radiation dose of 7 kGy is sufficient to eliminate the total number of microorganisms (excluding molds) to the extent that the number falls below the permitted limit according t o the law on the microbiological safety of foodstuffs of the Republic of Serbia, and 5 kGy is enough for molds to be rendered inactive. It was also concluded that gamma irradiation does not affect the nutritional value of lyophilized berries

Work analysis in emergency neurological department of University Hospital Split in one-year period

Prenapučenost odjela hitne službe rastući je problem u hitnim službama diljem svijeta. Cilj našeg istraživanja bio je utvrditi stupanj opterećenosti Hitnoga neurološkog prijema (HNP) Kliničkoga bolničkog centra (KBC) Split, utvrditi najučestalije razloge dolaska i procijeniti njihovu opravdanost. Napravili smo retrospektivnu analizu svih bolesnika pregledanih u našem HNP-u tijekom jednogodišnjeg razdoblja. U tom periodu pregledano je ukupno 8.146 pacijenata, u prosjeku 22 bolesnika na dan. Najučestaliji razlog dolaska je bio moždani udar (1.822 bolesnika – 22%), ali više od polovice pregledanih pacijenata procijenjeni su kao ne-hitni bolesnici i upućeni su na daljnju ambulantnu obradu. Čak 1.616 pacijenata prezentiralo se sa (sub)akutnim tegobama vratnog i leđnog dijela kralježnice. Ovim istraživanjem dokazali smo preopterećenost HNP-a i postojanje vrlo velikog broja ne-hitnih bolesnika u hitnom prijemu. Smatramo da bi bolja edukacija bolesnika, ali i liječnika obiteljske medicine i hitne medicine trebala pomoći u rješavanju ove problematike.Overcrowding of emergency departments all over the world has been recognised as one of the growing problems. The aim of our investigation was to determine the level of overcrowding in the neurological emergency room of the University Hospital Centre Split. This is a retrospective analysis of all patients that were examined in our emergency reception during the one-year period. We examined 8146 patients (around 22 patients per day). The main reason of their arrival was stroke (1,822 patients – 22%) but more than half of the patients were judged as non- urgent and they were sent to outpatient treatment. A total of 1,616 patients presented to the emergency department with (sub)acute complaints of cervical or lumbar spine. With this investigation we proved that there is a problem of overcrowding in our neurological emergency room and the existence of a very large number of non-urgent patients. We believe that better education of patients and doctors could be the solution of this problem

Comparative properties of composite poly(lactic-co-glycolic acid)/poly(acrylic acid) implants synthesized using ultraviolet and gamma irradiation

Composite implants comprising a biodegradable hydrophobic polymer matrix and crosslinked hydrogel with fixed ion exchange groups are promising materials for the construction of controlled drug delivery systems. Poly(lactic-co-glycolic acid)/poly(acrylic acid) (PLGA/PAA) composite implants in our study were synthesized using the sequential application of irradiation and immersion precipitation. Precursor solutions with all functional components were dispensed into a disc-shaped non-stick mold and cured either by ultraviolet (UV) or gamma irradiation. Cured disks were subsequently immersed in the phosphate buffer saline bath to finalize phase separation and solidification of the implants. The synthesized implants were characterized by FTIR-ATR and DSC, and their basic properties such as ion exchange capacity, swelling degree, and swelling kinetics were examined. Synthesis using gamma irradiation resulted in implants with similar ion exchange capacity, but the greater swelling degree and faster swelling kinetics compared to the implants prepared with UV irradiation. Gamma irradiation also resulted in altered and less homogeneous chemical composition compared to the implants synthesized with UV irradiation. Further investigations are required to determine the differences in drug release kinetics and degradation behavior of the synthesized implants

Use of low-energy electron-beam in the treatment of special food products with a high protein content

Special high-protein foods suitable for diabetics must be treated to ensure the complete absence of microorganisms and bacteria. It is also important to achieve that this treatment does not change the nutritional value of the product. Among the new decontamination technologies, low-energy electron-beam treatment has proven to be an effective technique for inactivating bacteria with minimal impact on food quality. The paper aims to analyze the influence of low-energy electron-beam irradiation on the microbiological properties and nutritional value of high-protein foods

Dose mapping of products with different density irradiated in 60co irradiation facility of the Vinca institute, Serbia

The distribution of the absorbed dose within the irradiated product is a complex function of the product density and homogeneity, the position and shape of the radiation source, as well as the design of the irradiator. In this paper, detailed mapping of absorbed radiation doses in products of different density: gauze, plastic, and soil, is performed. Positions of minimum and maximum absorbed radiation dose were determined, and the homogeneity of irradiation of products was calculated using the ethanol-monochlorobenzene oscillotitrator dosimetry system

Use of high-energy ionizing radiation for microbiological decontamination of coastal soil in the Kolubara river basin, Serbia

The Kolubara river pollutes the coastal land in the river basin and makes it unsuitable for agricultural activities in that area. Also, contaminated land poses a risk to the environment. Different methods can be used for soil decontamination. These methods include biological treatment/bioremediation, chemical oxidation, soil stabilization, physical methods, such as soil leaching, or treatment with high-energy ionizing radiation. Gamma irradiation of soil is a well-known method of inhibiting microbial activity. This paper investigated the influence of different doses and dose rates of gamma irradiation on microorganisms' decontamination of coastal soil, in the Kolubara river basin. The irradiation effects on reducing the total number of microorganisms and removing mold and pathogenic bacteria from soil samples were examined. Gamma radiation affects the soil's organic matter, causing the formation of free reactive radicals, which act as reducing and oxidizing agents, cleaving C-C bonds, and depolymerizing carbohydrates. It was found that a dose of 3 kGy of gamma radiation, neutralizes all pathogenic bacteria, a dose of 5 kGy deactivates mold in soil samples, and a dose of 10 kGy is optimal to kill all microorganisms in the samples and sterilize exposed soil. The research showed that the dose rate does not significantly affect microbiological decontamination of soil using gamma irradiation. The content of heavy metals in soil was determined, and the obtained values were compared with the remediation limit values prescribed by the regulations. It was concluded that the content of heavy metals in the analyzed soil samples is below the limit of remediation values. The only exception is the slightly increased copper content in one sample. The result of this research is the conclusion that the coastal land from the Kolubara basin can be decontaminated by gamma radiation treatment. This advanced soil treatment technology is available in Serbia because there is an industrial plant for gamma radiation treatment within the Vinča Institute

Accuracy in determining absorbed irradiation dose at different temperature measurements using ethanol chlorobenzene - oscillotitrator system

Elhanol-chlorobenzene/oscillolilralor dosimetry system is widely used in controlling the irradiation process in gamma facilities. The elhanol-chlorobenzene dosimetry system provides a reliable means of measuring absorbed dose. It is based on a process of radiolytic formation of hydrochloric acid in aqueous elhanolic solutions of chlorobenzene by ionizing radiation. The irradiation temperature dependence of dosimeter response is a complex function of dose and temperature for each concentration of chlorobenzene. At different temperature the mobility of conducting species from hydrochloric acid is changed leading to dilTerenl oscillolilralor deflections during high-frequency conduclomelric readout. In this paper, we examined the influence of temperature on the calculation of the radiation dose. We showed that the temperature significantly influenced the measurement results, and that the calibration curve has to be formed at the irradiation temperature in order to obtain precise values of the absorbed dose. © 2018; Vinca Inst Nuclear Sci. All rights reserved

Production of liqueur from green walnuts using ionizing radiation

Liqueur from green walnuts is one of the many traditional medicines in folk medicine. It owes its healing properties to the main ingredient - unripe green walnuts. Green walnuts are a natural reservoir of vitamin C, vitamin B complex, vitamin E, calcium, potassium, magnesium, phosphorus, iron, zinc and iodine. Liqueur made from green walnuts is mostly used for problems with the thyroid gland, anemia, and various stomach infections. The liqueur is made by adding green walnuts to a container with sugar or honey and brandy, and leaving them to be exposed to the sun's rays for a period of 40 days. Photons accelerate the release of medicinal substances from green walnuts. This period of exposure is quite long, the quality of the liqueur is affected by the amount of solar energy delivered during that period, and contamination may occur during manual handling. All these problems can be solved by using photons from a radioactive gamma source instead of photons from the sun. The paper describes the process of obtaining liqueur from green walnuts using gamma radiation, as well as the comparison of the composition of liqueur obtained in the traditional way, with the effect of sunlight, and the application of an innovative method using gamma rays.RAD 2023 : 11th International Conference on Radiation Natural Sciences, Medicine, Engineering, Technology and Ecology (RAD 2023) 19–23.06.2023; Herceg Novi, Montenegr

Removal of Cd2+ ions from aqueous solutions by gamma irradiation activated biochar of plum pomace

The use of waste biomass for the production of fuels, sorbent of different pollutants or natural fillers has significant economic and environmental benefits. Plum (Prunus domestica) is a lush fruit consisting of bones, flesh and skin. It can be consumed fresh, dried or used to make juices, jams and brandies known as plum brandy. Plum is also known as a laxative. During processing, plum pomace is formed as a by-product of plum brandy production. Plum pomace contains a large proportion of polyphenols, so it can be used to produce dietary supplements. Therefore, in this study, the gamma irradiation activated biochar of plum pomace was examined as a lowcost biosorbent of Cd2+ ions from aqueous solution. It was prepared using pyrolysis process at 500 °C for a reaction time of 1 h, then was activated by gamma irradiation. The characterization of plum pomace before and after pyrolysis was done by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Analysis of morphology and functional groups presented the formation of cracks on the biochar surface, which are mainly dominated by oxygen-rich functional groups. The adsorption capacity of activated biochar was higher than inactivated biochar because its improved surface functional properties after gamma activation. The Cd2+ ions contents in aqueous solution were analyzed using ICP-OES. The adsorption capacity was estimated using the Langmuir and Freundlich model. The findings of this study confirm that pyrolysis is a promising way to produce efficient environmentally friendly sorbents for wastewater treatment.X JUBILEE International Conference on Radiation in Various Fields of Research : RAD 2022 (Spring Edition) : book of abstracts; June 13-17, 2022; Herceg Novi, Montenegr

Fig pomace biochar modified using gamma irradiation for Pb2+ ions adsorption from aqueous solution

Fig (Ficus carica L.) is a fruit of the Moraceae family, which is mostly grown in subtropical regions, but also grows in Serbia. Fig trees are usually grown in warm and dry climates. According to the FAO world production of figs is stable, with a decade-long average of about 1.1 million tons a year. Fig pomace are formed after fermentation of this fruit which is used for the preparation of brandy. The brandy industry generates huge amounts of pomace as industrial waste, so pyrolysis as thermochemical technologies was used for organic agro-industrial waste treatment. Biochar produced by pyrolysis of fig pomace at 500 °C were characterized and investigated as adsorbents for the removal of Pb2+ ions from aqueous solution. Fig pomace before and after pyrolysis was characterized using proximate, inorganic and elemental analysis, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Biochar has a carbon matrix with a high degree of porosity and large surface area, suggesting that it can be used as a surface adsorbent and thus have a significant role in controlling environmental contaminants. The surface modification by gamma irradiation was done to enhance the adsorption capacity of biochar. The Pb2+ ions contents in aqueous solution were analyzed using ICP-OES. The adsorption capacity was estimated using the Freundlich and Langmuir model. The results of this work suggest that pyrolysis and irradiation of biomass is a promising way to produce efficient heavy metal sorbents for waste-water treatment.X JUBILEE International Conference on Radiation in Various Fields of Research : RAD 2022 (Spring Edition) : book of abstracts; June 13-17, 2022; Herceg Novi, Montenegr