Gibbs energy

U ovom završnom radu opisana je slobodna Gibbsova energija, koje su karakteristike i kako se ponaša pri određenim uvijetima. Slobodna Gibbsova energija dobila je ime po američkom fizičaru i kemičaru Josiah Willard Gibbs. Gibbs je proučavao kemijske reakcije te odnos sustava reakcije i okoline. Uočio je što je slobodna energija, koji su kriteriji spontanosti reakcija te pri kojim uvijetima se moţe izračunati promjena slobodne energije. Za poznavanje Gibbsove energije potrebno je poznavati uvijete u kojima se reakcija odvija te entropiju i entalpiju sustava koji su u radu ukratko objašnjeni. Standardne Gibbsove energije imaju konstantne vrijednosti, ali se podaci mogu prilagoditi drugim uvijetima te izračunati promjenu Gibbsove energije pri drugoj temperaturi i tlaku. U radu je objašnjena poveznica između konstante ravnoteţe i Gibbsove energije kao i aktiviteta otopina.This final work describes the free Gibbs energy, what are the characteristics and how it behaves under certain conditions. Free Gibbs energy is named after American physicist and chemist Josiah Willard Gibbs. Gibbs studied chemical reactions and the relationship between reaction systems and the environment. He noticed what free energy is, what are the criteria for spontaneity of reactions and under what conditions the change in free energy can be calculated. In order to calculate Gibbs energy, it is necessary to know the conditions under which the reaction takes place, and the entropy and enthalpy of the systems, which are briefly explained in the paper. The standard Gibbs energies have constant values, but the data can be adjusted to other conditions and the Gibbs energy change can be calculated at a different temperature and pressure. The relationship between the equilibrium constant and Gibbs energy as well as the activity of the solutions is explained in the paper

The history and prevention of food counterfeiting

Krivotvorenje hrane pojava je poznata još od Staroga vijeka, odnosno početka razmjene i trgovine, a ovisila je o području i uvjetima života. Definicija, kao i metode otkrivanja krivotvorenja mijenjale su se tijekom vremena zajedno s razvojem znanosti i tehnologije. Najveća količina krivotvorenih proizvoda pojavila se u vrijeme industrijalizacije, zbog loših životnih uvjeta, neinformiranosti potrošača i gotovo nikakvih sankcija. Problem se pokušavao riješiti primjenom zakona koji su u početku bili lokalni, no globalizacijom i razvojem međunarodne trgovine javljaju se i međunarodni zakoni. Unatoč velikom broju zakona, inspekcija i kontrola krivotvorenje postoji i danas, a kao pokušaj obrane od toga predlaže se informirati potrošače, stvoriti uvjete koji će smanjiti krivotvorenje, dati brži odgovor nadležnih institucija vezan uz povlačenje neispravne hrane s tržišta te postrožiti kazne po tomu pitanju.Counterfeiting of food is an phenomenon know since ancient history, that is since time of exchange and trade and it depended on area and living conditions. Definition, same as methods of detection of adulteration have changed during the history together with development of science and technology. The biggest amount of counterfeit products appeared during the industrialization due to bad living conditions, lack of informations among consumers and almost none of sanctions. Solution for this problem was tried to be found through use of laws, first local ones and then, because of globalization and development of international trade, international laws. Despite a large number of laws, inspections and controls, counterfeiting is still happening, and as attempt of defence it is proposed to inform consumers, to create conditions which will reduce adulteration, to give faster response from competent institutions regarding the recall of defective food from the market and to tighten penalties

(2E)-10-hydroxydec-2-enoic acid in royal jelly as determined by liquid chromatography

Matična mliječ je proizvod koji izlučuju mlade pčele radilice, a pripisuje joj se višestruko pozitivno djelovanje na organizam. To djelovanje je u najvećoj mjeri rezultat prisutnosti (2E)-10-hidroksidec-2-enske kiseline (10-HDA) koja je prisutna isključivo u matičnoj mliječi, pa se njezin udio smatra jednim od kriterija određivanja autentičnosti i kvalitete matične mliječi. Ne postoje međunarodni standardi za kvalitetu matične mliječi niti standardna metoda za određivanje udjela 10-HDA u matičnoj mliječi. HPLC metoda s detektorom s nizom dioda je validirana i upotrjebljena za određivanje udjela 10-HDA u svježoj matičnoj mliječi. Identifikacija 10-HDA provedena je na osnovi usporedbe vremena zadržavanja i apsorpcijskog spektra sa standardom 10-HDA, a kvantifikacija je provedena internom kalibracijom. Izvedbene značajke metode pokazale su da je metoda prikladna namjeni. Udio 10-HDA u 5 svježih uzoraka matične mliječi iznosio od 1,56 do 3,78 %. Prema preporukama o parametrima kvalitete matične mliječi koji predlažu da udio 10-HDA iznosi minimalno 1 %, uzorci korišteni u ovom istraživanju su svježi i nekrivotvoreni. Vrsta ambalažnog materijala nema utjecaj na udio 10-HDA u svježoj matičnoj mliječi ako se uzorak nakon vađenja smrzne i skladišti u zamrzivaču.Royal jelly is a product secreted by young worker bees, which has multiple positive effects on human health. They are mainly result of the presence of (2E)-10-hydroxydec-2-enoic acid (10-HDA), a component present only in royal jelly and its content is considered as one of the criteria for determining the authenticity and quality of royal jelly. There is neither international standard for the royal jelly quality nor standard method for determination of 10-HDA in royal jelly samples. HPLC method with absorbance detection was validated and used for the determination of 10-HDA in fresh royal jelly samples. Identification of the 10-HDA was performed based on comparison of retention times and absorbance spectrum 10-HDA of royal jelly sample compared with the spectrum of standard 10-HDA, and quantification was carried out by internal calibration. Method performance characteristics showed that the method was fit for purpose. The 10-HDA content in 5 fresh royal jelly samples was from 1.56 to 3.78 %. According to the recommendations on the royal jelly quality, that proposed a minimum 10-HDA content of 1 %, samples used in this study are fresh and authentic. Packaging type has no effect on 10-HDA content in fresh royal jelly, if samples are frozen after extraction and kept in freezer until analysis

(2E)-10-hydroxydec-2-enoic acid in royal jelly as determined by liquid chromatography

Matična mliječ je proizvod koji izlučuju mlade pčele radilice, a pripisuje joj se višestruko pozitivno djelovanje na organizam. To djelovanje je u najvećoj mjeri rezultat prisutnosti (2E)-10-hidroksidec-2-enske kiseline (10-HDA) koja je prisutna isključivo u matičnoj mliječi, pa se njezin udio smatra jednim od kriterija određivanja autentičnosti i kvalitete matične mliječi. Ne postoje međunarodni standardi za kvalitetu matične mliječi niti standardna metoda za određivanje udjela 10-HDA u matičnoj mliječi. HPLC metoda s detektorom s nizom dioda je validirana i upotrjebljena za određivanje udjela 10-HDA u svježoj matičnoj mliječi. Identifikacija 10-HDA provedena je na osnovi usporedbe vremena zadržavanja i apsorpcijskog spektra sa standardom 10-HDA, a kvantifikacija je provedena internom kalibracijom. Izvedbene značajke metode pokazale su da je metoda prikladna namjeni. Udio 10-HDA u 5 svježih uzoraka matične mliječi iznosio od 1,56 do 3,78 %. Prema preporukama o parametrima kvalitete matične mliječi koji predlažu da udio 10-HDA iznosi minimalno 1 %, uzorci korišteni u ovom istraživanju su svježi i nekrivotvoreni. Vrsta ambalažnog materijala nema utjecaj na udio 10-HDA u svježoj matičnoj mliječi ako se uzorak nakon vađenja smrzne i skladišti u zamrzivaču.Royal jelly is a product secreted by young worker bees, which has multiple positive effects on human health. They are mainly result of the presence of (2E)-10-hydroxydec-2-enoic acid (10-HDA), a component present only in royal jelly and its content is considered as one of the criteria for determining the authenticity and quality of royal jelly. There is neither international standard for the royal jelly quality nor standard method for determination of 10-HDA in royal jelly samples. HPLC method with absorbance detection was validated and used for the determination of 10-HDA in fresh royal jelly samples. Identification of the 10-HDA was performed based on comparison of retention times and absorbance spectrum 10-HDA of royal jelly sample compared with the spectrum of standard 10-HDA, and quantification was carried out by internal calibration. Method performance characteristics showed that the method was fit for purpose. The 10-HDA content in 5 fresh royal jelly samples was from 1.56 to 3.78 %. According to the recommendations on the royal jelly quality, that proposed a minimum 10-HDA content of 1 %, samples used in this study are fresh and authentic. Packaging type has no effect on 10-HDA content in fresh royal jelly, if samples are frozen after extraction and kept in freezer until analysis

Coumarin in grounded cinnamon and teas containing cinnamon - extraction and determination by HPLC method

Cinnamon, a commonly used spice as well as a part of many commodities, such as breakfast cereals, teas and bakery products, represents an important part of the diet. Cinnamon, among many bioactive components, contains an important active compound coumarin. Numerous studies have shown that coumarin has a beneficial health effect on the body in optimal consumption, while increased long-term consumption can lead to adverse health effects. In this paper, the amount of coumarin in ten different products found on the Croatian market, including ground spices and teas, was analyzed. In addition, different extraction parameters were analyzed in order to find the best method of extraction of coumarin from cinnamon and products containing cinnamon

ULTRASOUND-ASSISTED EXTRACTION OF ACTIVE COMPOUNDS FROM COCOA BEAN SHELL

In today\u27s overcrowded world with declining food supplies and the constant struggle against waste accumulation, scientists are increasingly trying to discover new ways to solve these problems. Like many industries, the food industry generates, disposes and accumulates waste thus creating an environmental and economic problem. In this study the one of the green extraction technologies, ultrasound-assisted extraction (UAE), for isolation of bioactive compounds from cocoa bean shell (CBS), a by-product in the chocolate production, was applied. Different temperature (40, 60, 80 °C), extraction time (30, 60, 90 minutes), liquid/solid ratio (10, 30, 50 mL/g) and ultrasound power (30, 50, 70 %) were used to obtain the cocoa bean shell extracts. Six active compounds were detected in the extracts by high performance liquid chromatography with a diode array detector as follows: theobromine (2.077-5.916 mg/g), gallic acid (0.110-1.407 mg/g), caffeine (0.276-0.785 mg/g), catechin (0.033-0.457 mg/g), while the highest obtained concentrations for epicatechin and caffeic acid were 0.100 and 0.527 mg/g of CBS. The highest total phenolic content (TPC) and % scavenging activity measured were 132.897 mgGAE/gextr. and 86.377%. From all investigated parameters, liquid/solid ratio had the greatest influence on the concentrations of obtained compounds. Study proved how UAE is an efficient method for the extraction of bioactive compounds from food by-product - CBS. It should also be emphasized that such application could find the purpose at the industrial level for the discarded waste that still contains valuable compounds, while the enriched extracts could be further used as raw material in other processes

ULTRASOUND-ASSISTED EXTRACTION OF ACTIVE COMPOUNDS FROM COCOA BEAN SHELL

In today\u27s overcrowded world with declining food supplies and the constant struggle against waste accumulation, scientists are increasingly trying to discover new ways to solve these problems. Like many industries, the food industry generates, disposes and accumulates waste thus creating an environmental and economic problem. In this study the one of the green extraction technologies, ultrasound-assisted extraction (UAE), for isolation of bioactive compounds from cocoa bean shell (CBS), a by-product in the chocolate production, was applied. Different temperature (40, 60, 80 °C), extraction time (30, 60, 90 minutes), liquid/solid ratio (10, 30, 50 mL/g) and ultrasound power (30, 50, 70 %) were used to obtain the cocoa bean shell extracts. Six active compounds were detected in the extracts by high performance liquid chromatography with a diode array detector as follows: theobromine (2.077-5.916 mg/g), gallic acid (0.110-1.407 mg/g), caffeine (0.276-0.785 mg/g), catechin (0.033-0.457 mg/g), while the highest obtained concentrations for epicatechin and caffeic acid were 0.100 and 0.527 mg/g of CBS. The highest total phenolic content (TPC) and % scavenging activity measured were 132.897 mgGAE/gextr. and 86.377%. From all investigated parameters, liquid/solid ratio had the greatest influence on the concentrations of obtained compounds. Study proved how UAE is an efficient method for the extraction of bioactive compounds from food by-product - CBS. It should also be emphasized that such application could find the purpose at the industrial level for the discarded waste that still contains valuable compounds, while the enriched extracts could be further used as raw material in other processes

Green extraction techniques of bioactive components from cocoa shell

The aim of this study was to demonstrate that certain types of extraction techniques can give extracts with various bioactive components in different concentrations. Four green extraction techniques were used in this study: supercritical CO2 extraction, ultrasound-assisted extraction, cold atmospheric plasma extraction and extraction using deep eutectic solvents. Those modern techniques gave better yields of bioactive components and showed better antioxidant activity of obtained extracts than classical Soxhlet extraction. The bioactive components in obtained extracts were quantified by High Performance Liquid Chromatography. Supercritical CO2 extraction gave the highest yields for theobromine content, while ultrasound-assisted extraction with 50% aqueous ethanol solution gave the highest caffeine yields during 30 min of extraction, 35 Hz and 60 °C. The extraction with deep eutectic solvent mixture of choline chloride: oxalic acid and 50% pure H2O at room temperature during 180 min of extraction time gave the highest total phenol content while the same mixture under the same conditions, but during longer extraction time (360 min), gave the highest antioxidant activity. Cocoa shell (CS), due to its nutritional value and bioactive components, has a potential to become a desirable raw material in a large spectrum of functional and pharmaceutical products

Determination of (2E)-10-hydroxydec-2-enoic acid in Croatian royal jelly by high-performance liquid chromatography

Although health-promoting properties of royal jelly are known for many years, the absence of quality standards and methods prescribed for their determination leads to royal jelly adulteration. Royal jelly is a source of unique unsaturated fatty acid, (2E)-10-hydroxydec-2-enoic acid (10-HDA), and its content is considered as one of the freshness and authenticity parameter. In this study, high performance liquid chromatographic method (HPLC) with UV detection was validated and 10-HDA content in fresh royal jelly samples produced in Eastern Croatia was determined. The data about Croatian royal jelly are not available, therefore the results presented in this study could be considered as pioneer results for Croatian royal jelly characterization in respect of the 10-HDA. Method performance characteristics showed that the used method is fit for purpose. The content of 10-HDA in analysed samples varied from 1.56% up to 3.78%. According to the international recommendations for royal jelly quality, samples were fresh and authentic regarding 10-HDA content. Furthermore, the effect of packaging material on 10-HDA content was observed. Based on the obtained results, the conclusion was reached that if the samples were collected at the same time and frozen after collection, collection and storage of fresh royal jelly in glass and plastic containers had no effect on 10-HDA content

CREATIVE PSYCHOPHARMACOTHERAPY IN CHILD AND ADOLESCENT PSYCHIATRY AND EXPERIENCES FROM BOSNIA AND HERZEGOVINA

Introduction: Paediatric psychopharmacology involves the application of psychotropic agents to the treatment of children and adolescents with mental disorders and gathered knowledge from child and adolescent psychiatry (CAP), neurology, paediatrics and pharmacology. Defining elements of this discipline are: the metabolism of drugs is different in children than in adults (pharmacokinetics), the developing brain reacts specifically to the drug (pharmaco dynamics), and psychopathology itself is not differentiated yet. To make and overview of specifics in psychopharmacological use in CAP and emphasize some experiences from Bosnia and Herzegovina in that field. Methods: Through insight in current literature, we presented comprehensive findings and compare it with situation in Bosnia and Herzegovina. Results: The most common conditions in which psycho pharmaceuticals are used in CAP were attention deficit hyperactivity disorders (ADHD), depressive and bipolar disorder, obsessive compulsive disorder and the treatment of early psychosis. Psycho pharmaceuticals were also used to treat agitated conditions in various causes. We made an overview of psycho pharmaceuticals use in Bosnia and Herzegovina CAP and emphasized the fact that psycho stimulants are not approved for the use yet, although they are mostly prescribed medicament in CAP over the world. That limits us in the effectiveness of the treatment in ADHD and put us in the situations to use other medicaments instead (anxiolytics, antipsychotics, mood stabilizers) which are not approved for that condition. Conclusion: The use of psycho pharmacotherapy in CAP is justified in cases where it is necessary to reduce the suffering of children and to improve their functionality at the time when cognitive, social and emotional advancement is most pronounced. Further research and clinical monitoring of efficacy and safety in the use of psycho pharmaceuticals in youngsters are necessary