130 research outputs found
Protection of stored plant products from rodent pests using chlorophacinone
Apart from some preventive measures, advisably taken during construction of storage facilities or at the time of product storage, treatments with chemical rodenticides have been the most widely practiced method of controlling commensal rodents. Their control in storages is normally carried out after animal presence has been observed, and treatments from early autumn onwards, throughout the season, provide the best effect. The paper shows the effects of baits with lower content of the active ingredient chlorophacinone than recommended for protecting stored plant products from rodents. The experiments were set up using the relevant OEPP/EPPO method. Different contents (0.005% and 0.0075%) of the active ingredient chlorophacinone were used in a ready for use (RB) paste bait formulation. Baits were laid in boxes along rodent routes, underneath pallets with sacks and in places where major damage was observed. Baits for house mice were placed at a rate of 10-20 g per 1-3 m, while 30-50 g of baits for brown rats were laid at specific points. Daily bait intake was monitored over a period of 10 d and the portions were replaced with new ones as needed. Placebo baits were laid in identical boxes for 4 d before the experiment began. The abundance of house mice was estimated based on the highest and lowest daily intake of bait divided by the species’ daily food requirement. The data in this experiment show that 0.005% and 0.0075% chorophacinone contents in RB baits changed neither palatability nor bait efficacy in controlling house mouse and brown rat indoors. The average efficacy of chorophacinone was 87-93% against house mouse and 90-100% against brown rat. Keywords: Chlorophacinone, Rodent, Storage, Efficac
The possibility of use of some essential oils in rodenticidal baits
Jokić, G., Vukša, M., Đedović, S., Stojnić, B., Kataranovski, D
High-Voltage Electric Discharge Extraction of Bioactive Compounds from the Cocoa Bean Shell
This study is focused on the application of high-voltage electric discharge (HVED) to recover some bioactive compounds from the cocoa bean shell. Different extraction times (30, 60, 90 min), frequencies (40, 70, 100 Hz) and solvent-solid ratios (10, 30 and
50 mL g–1) were used to obtain cocoa bean shell extracts. Desired bioactive compounds, methylxanthines and phenolic compounds were measured in obtained extracts by high-pressure liquid chromatography with diode array detector. The obtained extracts
showed that theobromine was the most abundant, ranging from 2530.13 to 6031.51 mg kg–1, while caffeine content was in the range from 316.08 to 849.88 mg kg–1. In addition, significant amounts of phenolic compounds were found, namely catechin (115.91 to 284.33 mg kg–1), epicatechin (20.20 to 358.90 mg kg–1), and gallic acid (80.28 to 219.17 mg kg–1). Results showed that different parameters of HVED extraction have statistically significant influence on cocoa bean shell composition, suggesting how this byproduct can be used in the production of valuable extracts.
This work is licensed under a Creative Commons Attribution 4.0 International License
Prilog poznavanju suzbijanja sivog pacova (Rattus norvegicus) na farmi mlečnih krava
Rattus norvegicus is a synanthropic species living almost exclusively around facilities for keeping domestic animals. This three-year research focused on options for reducing economic damage caused by this rodent species in stables for heavy milking cows by testing preparations with active substances of various origin. It involved an environmentally friendly product based on sodium selenite 0.1%, a cholecalciferol-based natural product 0.75%, as well as anticoagulant rodenticides containing the active substances bromadiolone 0.005% and brodifacoum 0.005%. These preparations were formulated as granules, plate bait or grain bait. The environmentally friendly sodium selenite product achieved 76.2% efficacy in the first year of research, 70% in the second, and 67.5% in the third. The synthetic products based on bromadiolone and brodifacoum demonstrated high efficacy in all of the three experimental years and in all three formulations. The cholecalciferol rodenticide had 71.4% efficacy in the first year, 68% in the second, and 67.7% in the third. The data show that the environmentally safe product had a lower efficacy due to high rodent abundance and inadequate epidemiological conditions existing on the farm of heavy milking cows, while the bromadiolone and brodifacoum-based products achieved high efficacy.Rattus norvegicus gotovo uvek živi u objektima namenjenim za gajenje domaćih životinja i kao sinanotropna vrsta prisutan je u čovekovoj najbližoj okolini. Predmet naših trogodišnjih istraživanja je alternativa smanjenja ekonomskih šteta koju pričinjava ovaj glodar u stajama farmi visoko-mlečnih krava, primenom preparata na bazi aktivnih materija različitog porekla. U eksperimentima je korišćen ekološko prihvatljivi preparat na bazi natrijum-selenita (0,1%), preparat prirodnog porekla na bazi holekalciferola (0,75%) i antikoagulantni rodenticidi na bazi bromadiolona (0,005%) i brodifakuma (0,005%). Primenjeni preparati su formulisani u obliku granula, obloženog i zrnastog mamka. Ekološko prihvatljivi preparat na bazi natrijum-selenita je ispoljio efikasnost od 76,2% u prvoj godini istraživanja, u drugoj 70% i u trećoj godini 67,5%. Sintetisani preparati na bazi bromadiolona i brodifakuma pokazali su visoku efikasnost u sve tri godine ispitivanja za sve tri navedene formulacije. Rodenticid na bazi holekalciferola je ispoljio efikasnost od 71,4% u prvoj godini, u drugoj 68% i u trećoj 67,7 %. Rezultati istraživanja ukazuju da je zbog velike brojnosti glodara i neadekvatnih epidemioloških uslova na farmi visoko-mlečnih krava ispoljena slabija efikasnost ekološko prihvatljivog preparata dok su preparati na bazi bromadiolona i brodifakuma ispoljili visoku efikasnost
Supplementary data for the article: Izrael Živković, L. T.; Živković, L. S.; Beškoski, V. P.; Gopčević, K. R.; Jokić, B. M.; Radosavljević, D. S.; Karadžić, I. M. The Candida Rugosa Lipase Adsorbed onto Titania as Nano Biocatalyst with Improved Thermostability and Reuse Potential in Aqueous and Organic Media. Journal of Molecular Catalysis B: Enzymatic 2016, 133, S533–S542. https://doi.org/10.1016/j.molcatb.2017.06.001
Supplementary material for: [https://doi.org/10.1016/j.molcatb.2017.06.001]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/315]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3648
Cold Pressing and Supercritical CO2 Extraction of Hemp (Cannabis sativa) Seed Oil
In the past few decades, the Cannabis sativa L. hemp variety has been unfairly neglected because of its similarity to the illegal kind Cannabis indica used as a narcotic. The objective of this study was to evaluate the process of oil extraction from Cannabis sativa seeds by cold pressing, followed by extraction with supercritical CO2. In the pressing experiments, the response surface methodology was conducted in order to study the effects of temperature, frequency, and nozzle size on oil recovery and quality parameters. The optimal condition for obtaining the highest oil recovery (23.34 %) and the best oil quality within the experimental range of the variables studied was at temperature of 60 °C, frequency of 20 Hz, and nozzle of ID 6 mm. The residual oil (10.33 %) in the press cake was extracted totally by supercritical CO2 in a newly designed supercritical fluid extraction system. Oregano essential oil was the most effective in protecting the oil from oxidative deterioration
Uticaj samodopovanja na elektrohemijsku sintezu i svojstva polianilina
Electrochemical synthesis was used to polymerize aniline and copolymerize aniline and m-aminobenzoic from aqueous acidic electrolyte containing aniline and aniline with different amount of m-aminobenzoic acid. These materials were obtained galvanostatically at graphite electrode at current density of 1.0 mA cm-2 from aqueous electrolyte containing 1.0 mol dm-3 HCl and different amount of monomers. The effect of self-doping due to meta positioned carboxylic group was observed in both synthesis parameters, morphology, degree of oxidation and electrochemical behaviour. The presence of m-aminobenzoic acid led higher copolymerization increasing with the increase of amount of m-aminobenzoic acid if comparing to polymerization potential of aniline. Moreover, the copolymer with equal amount of aniline/m-aminobenzoic acid showed electrochemical activity in neutral electrolyte which might be due to possibility of proton exchange process which can be expelled from the copolymer during oxidation process together by insertion of anions, making this material promising for use in electrochemical biosensors.Elektrohemijski postupak korišćen je za polimerizaciju anilina i kopolimerizaciju anilina i m-aminobenzoeve kiseline iz kiselog vodenog rastvora elektrolita sa različitim molskim odnosima anilina i m-aminobezoeve kiseline. Ovi materijali dobijeni su uslovima konstantne gustine struje od 1,0 mA cm-2 iz kiselog vodenog elektrolita koji je sadržavao 1,0 mol dm-3 HCl, anilin i m-aminobenzoevu kiselinu. Uticaj samo-dopovanja koji je posledica prisustva karboskilne grupe u meta položaju ispoljavao se u različitim parametrima sinteze, morfologiji dobijenih materijala, stepenu oksidacije i elektrohemijskom ponašanju. Prisustvo m-aminobenzoeve kiseline uslovilo je veći potencijal sinteze kopolimera u odnosu na polianilin koji je rastao sa porastom udela m-aminobezoeve kiseline. Kopolimer koji je dobijen iz elektrolita sa jednakim molskim odnosom anilina i m-aminobenzoeve kiseline pokazao je elektrohemijsku aktivnost u neutralnom elektrolitu koja može biti posledica razmene protona što ovaj materijal čini perspektivnim za praktičnu primenu u elektrohemijskim biosenzorima
An impact of Croatian journals measured by citation analysis from SCI-expanded database in time span 1975–2001
The Candida rugosa lipase adsorbed onto titania as nano biocatalyst with improved thermostability and reuse potential in aqueous and organic media
The immobilization of Candida rugosa lipase by adsorption was performed onto commercial titania powder (Degussa P25). The change of titania particles surface was diagnosed by means of FTIR and FESEM analysis, as well as by shift of zeta potential value towards that of lipase. A detailed study of the effect of immobilization on enzyme kinetic, temperature stability, as well as on potential for its reuse in aqueous organic media was undertaken. Immobilization of lipase altered enzyme affinity toward substrates with different length of carbon chain in hydrolytic reaction. The Vmax value decreased 2–8-fold, where major constraint was registered for the ester containing the longest carbon chain. Thermostability of lipase improved more than 7-fold at 60 °C. Significant potential for reuse in water solutions was also found after immobilization. In cyclohexane immobilized lipase catalyzed synthesis of amyl octanoate by ping-pong bi–bi mechanism with inhibition by amyl alcohol. Obtained kinetic constants were Vmax = 26.4 μmol min−1, KAc = 0.52 mol/L, KAl = 0.2 mol/L and Ki,Al = 0.644 mol/L. Esterification activity remained 60% after 5 reuse cycles in cyclohexane indicating moderate reuse stability. © 2017 Elsevier B.V.This is peer-reviewed version of the following article: Izrael Živković, L. T.; Živković, L. S.; Beškoski, V. P.; Gopčević, K. R.; Jokić, B. M.; Radosavljević, D. S.; Karadžić, I. M. The Candida Rugosa Lipase Adsorbed onto Titania as Nano Biocatalyst with Improved Thermostability and Reuse Potential in Aqueous and Organic Media. Journal of Molecular Catalysis B: Enzymatic 2016, 133, S533–S542. [https://doi.org/10.1016/j.molcatb.2017.06.001]Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3649
Supplementary data for the article: Izrael Živković, L. T.; Živković, L. S.; Beškoski, V. P.; Gopčević, K. R.; Jokić, B. M.; Radosavljević, D. S.; Karadžić, I. M. The Candida Rugosa Lipase Adsorbed onto Titania as Nano Biocatalyst with Improved Thermostability and Reuse Potential in Aqueous and Organic Media. Journal of Molecular Catalysis B: Enzymatic 2016, 133, S533–S542. https://doi.org/10.1016/j.molcatb.2017.06.001
Supplementary material for: [https://doi.org/10.1016/j.molcatb.2017.06.001]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/315]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3648
- …