Valentina Christova-Bagdassarian - Academia.edu (original) (raw)

Papers by Valentina Christova-Bagdassarian

Research paper thumbnail of Short Communication DETERMINATION OF TANNINS CONTENT BY TITRIMETRIC METHOD FOR COMPARISON OF DIFFERENT PLANT SPECIES

Research paper thumbnail of Similar names in academic literature as a tools to deceive researchers

International Journal of Advanced Intelligence Paradigms, 2016

Research paper thumbnail of Determination of Dibutyl Phthalate (DBP), Benzyl Butyl Phthalate (BBP) and Bis (2-ETHYLHEXYL) Phthalate (Dehp) in Soft Plastic Toys and the First Survey of the Bulgarian Market

DOAJ (DOAJ: Directory of Open Access Journals), Dec 1, 2017

Research paper thumbnail of Migration of primary aromatic amines from polyamide kitchenware

Food contact materials include both packaging materials and utensils, plates, containers, process... more Food contact materials include both packaging materials and utensils, plates, containers, processing machines, etc. The use of plastic utensils for cooking and frying (spatulas, stirrers, utensils for overturning food, ladles, slotted spoons or having other forms) has increased in recent years, as these items are inexpensive and unbreakable, available widely in the market, relatively resistant to high temperatures and do not scratch the surface of the dishes. Most of them are made of different types of nylon, known under the chemical name Polyamide (PA). If the monomer ratio is well balanced, and the reaction of the chemical synthesis is completed, all the monomers are incorporated into the polymer structure. When the balance between monomers is inappropriate, however, free monomers or socyanates remain and can migrate to food and to form primary aromatic amines (PAA). PAA can end up in food as residual monomers from food contact materials, as hydrolysis products of isocyanates or as contaminants from azo dyes. They may be formed chemically in food or to migrate to it from food contact materials if they are not produced in compliance with good manufacturing practice. The primary aromatic amines are a family of compounds, some of which are classified by the International Agency for Research on Cancer as «possibly carcinogenic to humans» and their presence in food should be avoided. In recent years, there was anxiety in the EU member states concerning received data for migration of primary aromatic amines from polyamide kitchenware imported from third countries. Regulation (EU) № 284/2011 lays down specific conditions and detailed procedures for the import of those articles and establishes maximum residue limits for specific migration of PAA. This article published a validated screening spectrometric method for the determination of total primary aromatic amines represented as aniline equivalent, which satisfies the requirements of Regulation 284/2011. The method is based on the diazotization of primary aromatic amines with sodium nitrite in acidic medium and subsequent neutralization of residual nitrosating agent with ammonium sulfamate. Nitro derivatives were coupled with N- (1-naphthyl) ethylenediamine dihydrochloride to yield violet colored complex, which was then concentrated by solid phase extraction. The measured absorbance at a wavelength of 550 nm is proportional to the total content of primary aromatic amines, expressed as aniline equivalents. The limit of detection LOD is 0.001 mg/kg, expressed as aniline; the limit of quantification LOQ is 0.002 mg/kg, expressed as aniline; the working range of the method is between 0.002 and 0.04 mg/kg, expressed as aniline. This method is applied for exploring the migration of primary aromatic amines from polyamide kitchen utensils available on the Bulgarian market. The obtained data do not show a potential risk for consumers from the migration of these substances from polyamide articles when the items are labeled with information about the origin, type of material, conditions of use and are used according to the label instructions. Items without marking and labeling, as well as those labeled with a non-useful information, for example, „made from harmless plastic” are not the subject of this study. the wide spread of such items requires caution regarding their safety for consumers.

Research paper thumbnail of Comparative Analysis of Total Phenolic and Total Flavonoid Contents, Rutin, Tannins and Antioxidant Capacity in Apiaceae and Lamiaceae families

Indian Horticulture Journal, 2014

Comparative evaluations of the total phenolic and total flafonoid contents, rutin, tannins and an... more Comparative evaluations of the total phenolic and total flafonoid contents, rutin, tannins and antioxidant capacity to various herbal spices from the Apiaceae and Lamiaceae families to which belong: Foeniculum vulgare (Fennel), Anethum graveolens (Dill), Pimpinella anisum (Anise), Carum carvi (Caraway), Coriandrum sativum (Coriander), Melissa officialis (Lemon balm), Salvia officialis (Sage) and Mentha piperita (Mint) were carried out. The herb and seed spices were analyzed for their tannins content by titrimetric method; rutin was determined spectrophotometrically by using ammonium molybdate; the total phenolic contents were determined by using Folin-Ciocalteu assay; the total flavonoids were measured spectrophotometrically using the colorimetric reaction with aluminum (III) chloride. Antioxidant capacity was also analysed spectrophotometrically by a 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effect of the herbs and seeds. The total phenolic and flavonoid contents of the Foeniculum vulgare (Fennel) varied between 115.96 mg GAE/100g and 68.10 mg CE/100g. This content for the Coriandrum sativum (Coriander) is lower (between 17.04 mg GAE/100g and 11.10 mg CE/100g, respectively). The content of rutin and tannins of the Melissa officialis (Lemon baim) varied between 3.10% and 10.79%. It was found to be much higher than the rutin content of the Coriandrum sativu (Coriander) (between 0.99% and 0.42%, respectively). The highest radical scavenging effect was observed in the Foeniculum vulgare (Fennel) with IC50 of 113.19 mL/L. In the present study, the seed spices from the Apiacea family and the herb spices from Lamiaceae family to which belong: Foeniculum vulgare (Fennel), Anethum graveolens (Dill), Pimpinella anisum (Anise), Carum carvi (Caraway), Coriandrum sativum (Coriander), Melissa officialis (Lemon balm), Salvia officialis (Sage) and Mentha piperita (Mint) were studied as sources of natural antioxidants. The results from the antioxidant assays show that all seeds and herbs can act as radical scavengers to a certain extent.

Research paper thumbnail of Phthalate esters - spread, exposure and toxicity

Phthalates (phthalate esters) are a large group of chemical compounds - phthalic acid esters of t... more Phthalates (phthalate esters) are a large group of chemical compounds - phthalic acid esters of the general chemical structure obtained by the reaction of phthalic anhydride with alcohols. They are mainly used as plasticizers for plastic materials, in solvents, in cosmetics and in other applications. Phthalates are not covalently bonded to the molecules of the plastic, and they are easily separated from it by the processes of direct release, migration, evaporation, leaching, and abrasion. This is a prerequisite for their penetration into the human organisms in various ways - ingestion, inhalation and dermal absorption and even intravenously. The contribution of the different sources in the complex exposure to phthalates is unknown. Available toxicological studies are predominantly carried out on animals, but due to the similarities in the metabolism, phthalates are suspected to cause health problems in humans as well. Their acute toxicity is very low, but subchronic and chronic toxicity of phthalates and their metabolites are significant. In animal studies, phthalates have been identified as endocrine disruptors, causing a number of symptoms, called “phthalate syndrome,” mainly because of their effects on the male reproductive system. Studies in young girls have also shown a possible connection between the shortening of pregnancy, the development of breast cancer and exposure to phthalates. Exposure to phthalates relates to all age groups. In the absence of the relevant human studies is difficult to fully assess the risk of these compounds to the human health. In the European Union, legislative measures to restrict the content of phthalates in packaged food and beverages, children’s personal care products and toys are available, as well as measures to regulate the industrial use of phthalates. A clear statement of the ingredients of the products would allow consumers to choose the appropriate alternatives.

Research paper thumbnail of Phthalate__ampersandsignnbsp;Plasticizers__ampersandsignnbsp;and__ampersandsignnbsp;Safety__ampersandsignnbsp;of__ampersandsignnbsp;Toys__ampersandsignnbsp;-__ampersandsignnbsp;Problems__ampersandsignnbsp;and__ampersandsignnbsp;Perspectives

Research paper thumbnail of A New Challenge in the Academic World : Earning Real Money and Eminence by Paper Publishing

Jordan Journal of Biological Sciences, 2015

Research paper thumbnail of 3-Monochloro-1,2-propandiol (3-MCPD) in soy sauce from the Bulgarian market

Food Additives & Contaminants Part B-surveillance, Sep 1, 2013

The 3-monochloro-1,2-propandiol (3-MCPD) levels in soy sauces which contained hydrolysed vegetabl... more The 3-monochloro-1,2-propandiol (3-MCPD) levels in soy sauces which contained hydrolysed vegetable protein were evaluated for the Bulgarian market. For analysis of 3-MCPD, a gas chromatography-mass spectrometry (GC-MS) method was applied with a linear range of 0.03-2.00 μg mL⁻¹ and a limit of detection (LOD) of 2.3 μg kg⁻¹ and a limit of quantification (LOQ) of 3.4 μg kg⁻¹. At these levels, the standard deviation was 5.1%, with recoveries between 81% and 102%. The method was applied to the analysis of 21 samples of soy sauce from the Bulgarian market. Results ranged from 3.7 to 185.6 μg kg⁻¹. Soy sauces produced from hydrolysed soy protein contained higher levels of 3-MCPD than naturally fermented sauces. In 38.4% of samples of Bulgarian origin, the 3-MCPD content was above the EU limit of 20 μg kg⁻¹. In all analysed samples, 33.3% had a 3-MCPD content above the EU limit.

Research paper thumbnail of Rutin Content in Plant Products

Research paper thumbnail of Migration of Melamine and Formaldehyde from Kids' Bamboo Dinner Sets

Food and Environment Safety Journal, 2021

Research paper thumbnail of Aflatoxins - Analysis and Risk Management

Mintage Journal of Pharmaceutical and Medical Sciences, 2014

Objective : The purpose of this study is to analyze and assess the risk associated with the prese... more Objective : The purpose of this study is to analyze and assess the risk associated with the presence of aflatoxins in food and feed. Aflatoxins are produced by Aspergillus flavus and Aspergillus parasiticus and they are distributed worldwide. Conclusions: Aflatoxins are a potential danger for both animal and human health. Attention should be paid to the potentially dangerous synergistic or additive effects on animal health arising from the presence of more than one mycotoxin in feed. Given the ubiquity of mycotoxins in the world, is also necessary to develop an effective program of risk management, which will be crucial to reduce costs and economic losses in farms associated with the risk of pollution

Research paper thumbnail of Qualitative Analysis of Evidence Regarding Heroin and Impurities for the Purposes of Forensic Medicine (For the Period 2000-2012)

The use of chemical substances affecting the human psyche is as old as human history. Drug abuse ... more The use of chemical substances affecting the human psyche is as old as human history. Drug abuse is a problem which can be examined from many aspects-medical, legal, social, criminological, etc. The heart of the problem is the spread of drugs and related damage to young people, at the expense of material interests of the people involved in the system of distribution. In Bulgaria in the years after 1989 drug problem became a current issue. This work describes the results from the analysis of objects collected as evidence at crime scenes in cases of deaths of drug addicts or drug intake by living persons. The samples, after liquid / liquid extraction or directly dissolved in methanol, were analyzed by using GC with NPD detector and composition of the mixture was determined by comparison of retention times of the individual components using standard substances. After 2012, mass spectrometric identification was used. Substances and impurities, established in "street" heroin an...

Research paper thumbnail of HPLC determination of cinnarizine in workplace air

Research paper thumbnail of Short Communication DETERMINATION OF TANNINS CONTENT BY TITRIMETRIC METHOD FOR COMPARISON OF DIFFERENT PLANT SPECIES

Research paper thumbnail of Influence on aeration rate on performance characteristics of cattle manure composting with different Carbon sources used as bulking agents

A study on the effect of different aeration rates on the speed of composting process was carried ... more A study on the effect of different aeration rates on the speed of composting process was carried with mixtures of cattle manure and three different carbon sources (sawdust, rice pods and sunflower husks) under controlled laboratory conditions. The performance characteristics of composting process were evaluated in terms of the evolution of temperature (T), pH, electrical conductivity (EC) and organic matter (OM) content. The single, one-time filling of the composting reactors with the compost mixture showed better performance characteristics over the gradual filling of the reactors. The aeration for 15 min/hour at the rate of 50 L air/min provided sufficient quantity of O2 for aerobic conditions in the composting mixtures. The compost mixtures with sunflower husks maintained longer thermophilic phase with higher average daily temperatures in comparison to the other two bulking agents.

Research paper thumbnail of Determination of Dibutyl Phthalate (DBP), Benzyl Butyl Phthalate (BBP) and Bis (2-ETHYLHEXYL) Phthalate (Dehp) in Soft Plastic Toys and the First Survey of the Bulgarian Market

Phthalates are a large group of compounds with similar chemical structure widely used as plastici... more Phthalates are a large group of compounds with similar chemical structure widely used as plasticizers for plastics. They can easily be released from the polymer during usage and in this way enter the human body. Their adverse effect on health is known as "phthalate syndrome" and can impact children and adults alike. For children in particular, there is an additional potential risk of exposure to phthalates via toys intended for oral use. The Regulation (EC) No 1907/2006 (REACH) prohibits the use of bis (2-ethylhexyl) phthalate (DEHP), di butyl phthalate (DBP) and benzyl butyl phthalate (BBP) as a substance or constituent of preparations at concentrations higher than 0.1 % in the plasticized material meant to toys and childcare items. The aim of this article is to quantify the content of DEHP, DBP and BBP in soft toys intended for children up to 3 years of age, including toys designed to be placed in the mouth. A method consisting of an extraction procedure of phthalates fr...

Research paper thumbnail of Comparative Analysis of Total Phenolic and Total Flavonoid Contents, Rutin, Tannins and Antioxidant Capacity in Apiaceae and Lamiaceae families

Indian Horticulture Journal, 2014

Comparative evaluations of the total phenolic and total flafonoid contents, rutin, tannins and an... more Comparative evaluations of the total phenolic and total flafonoid contents, rutin, tannins and antioxidant capacity to various herbal spices from the Apiaceae and Lamiaceae families to which belong: Foeniculum vulgare (Fennel), Anethum graveolens (Dill), Pimpinella anisum (Anise), Carum carvi (Caraway), Coriandrum sativum (Coriander), Melissa officialis (Lemon balm), Salvia officialis (Sage) and Mentha piperita (Mint) were carried out. The herb and seed spices were analyzed for their tannins content by titrimetric method; rutin was determined spectrophotometrically by using ammonium molybdate; the total phenolic contents were determined by using Folin-Ciocalteu assay; the total flavonoids were measured spectrophotometrically using the colorimetric reaction with aluminum (III) chloride. Antioxidant capacity was also analysed spectrophotometrically by a 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effect of the herbs and seeds. The total phenolic and flavonoid contents of t...

Research paper thumbnail of Phthalate esters - spread, exposure and toxicity

Phthalates (phthalate esters) are a large group of chemical compounds - phthalic acid esters of t... more Phthalates (phthalate esters) are a large group of chemical compounds - phthalic acid esters of the general chemical structure obtained by the reaction of phthalic anhydride with alcohols. They are mainly used as plasticizers for plastic materials, in solvents, in cosmetics and in other applications. Phthalates are not covalently bonded to the molecules of the plastic, and they are easily separated from it by the processes of direct release, migration, evaporation, leaching, and abrasion. This is a prerequisite for their penetration into the human organisms in various ways - ingestion, inhalation and dermal absorption and even intravenously. The contribution of the different sources in the complex exposure to phthalates is unknown. Available toxicological studies are predominantly carried out on animals, but due to the similarities in the metabolism, phthalates are suspected to cause health problems in humans as well. Their acute toxicity is very low, but subchronic and chronic toxicity of phthalates and their metabolites are significant. In animal studies, phthalates have been identified as endocrine disruptors, causing a number of symptoms, called “phthalate syndrome,” mainly because of their effects on the male reproductive system. Studies in young girls have also shown a possible connection between the shortening of pregnancy, the development of breast cancer and exposure to phthalates. Exposure to phthalates relates to all age groups. In the absence of the relevant human studies is difficult to fully assess the risk of these compounds to the human health. In the European Union, legislative measures to restrict the content of phthalates in packaged food and beverages, children’s personal care products and toys are available, as well as measures to regulate the industrial use of phthalates. A clear statement of the ingredients of the products would allow consumers to choose the appropriate alternatives.

Research paper thumbnail of Soild-Liquid Extraction Kinetics of Total Phenolic, Total Flavonoid, Rutin and Tannin Contents in 50% Ethanol Extract of Cotinus coggygria

International Journal of Scientific & Engineering Research, 2016

phytoconstituents show that the dry leaves of Cotinus coggygria are rich in total phenols, total ... more phytoconstituents show that the dry leaves of Cotinus coggygria are rich in total phenols, total flavonoids, rutin and tannins. Solid–liquid extraction was carried out by 50% aqueous ethanol for 120 min, which gave concentration of total polyphenols and the findings of our present results are within good agreement with the other workers. . Index Terms— Rutin, Tannins, Total flavonoids, Total phenolics, Solid–liquid extraction, 50% aqueous ethanol extract of Bulgar-ian dry leaves of Cotinus coggygria

Research paper thumbnail of Short Communication DETERMINATION OF TANNINS CONTENT BY TITRIMETRIC METHOD FOR COMPARISON OF DIFFERENT PLANT SPECIES

Research paper thumbnail of Similar names in academic literature as a tools to deceive researchers

International Journal of Advanced Intelligence Paradigms, 2016

Research paper thumbnail of Determination of Dibutyl Phthalate (DBP), Benzyl Butyl Phthalate (BBP) and Bis (2-ETHYLHEXYL) Phthalate (Dehp) in Soft Plastic Toys and the First Survey of the Bulgarian Market

DOAJ (DOAJ: Directory of Open Access Journals), Dec 1, 2017

Research paper thumbnail of Migration of primary aromatic amines from polyamide kitchenware

Food contact materials include both packaging materials and utensils, plates, containers, process... more Food contact materials include both packaging materials and utensils, plates, containers, processing machines, etc. The use of plastic utensils for cooking and frying (spatulas, stirrers, utensils for overturning food, ladles, slotted spoons or having other forms) has increased in recent years, as these items are inexpensive and unbreakable, available widely in the market, relatively resistant to high temperatures and do not scratch the surface of the dishes. Most of them are made of different types of nylon, known under the chemical name Polyamide (PA). If the monomer ratio is well balanced, and the reaction of the chemical synthesis is completed, all the monomers are incorporated into the polymer structure. When the balance between monomers is inappropriate, however, free monomers or socyanates remain and can migrate to food and to form primary aromatic amines (PAA). PAA can end up in food as residual monomers from food contact materials, as hydrolysis products of isocyanates or as contaminants from azo dyes. They may be formed chemically in food or to migrate to it from food contact materials if they are not produced in compliance with good manufacturing practice. The primary aromatic amines are a family of compounds, some of which are classified by the International Agency for Research on Cancer as «possibly carcinogenic to humans» and their presence in food should be avoided. In recent years, there was anxiety in the EU member states concerning received data for migration of primary aromatic amines from polyamide kitchenware imported from third countries. Regulation (EU) № 284/2011 lays down specific conditions and detailed procedures for the import of those articles and establishes maximum residue limits for specific migration of PAA. This article published a validated screening spectrometric method for the determination of total primary aromatic amines represented as aniline equivalent, which satisfies the requirements of Regulation 284/2011. The method is based on the diazotization of primary aromatic amines with sodium nitrite in acidic medium and subsequent neutralization of residual nitrosating agent with ammonium sulfamate. Nitro derivatives were coupled with N- (1-naphthyl) ethylenediamine dihydrochloride to yield violet colored complex, which was then concentrated by solid phase extraction. The measured absorbance at a wavelength of 550 nm is proportional to the total content of primary aromatic amines, expressed as aniline equivalents. The limit of detection LOD is 0.001 mg/kg, expressed as aniline; the limit of quantification LOQ is 0.002 mg/kg, expressed as aniline; the working range of the method is between 0.002 and 0.04 mg/kg, expressed as aniline. This method is applied for exploring the migration of primary aromatic amines from polyamide kitchen utensils available on the Bulgarian market. The obtained data do not show a potential risk for consumers from the migration of these substances from polyamide articles when the items are labeled with information about the origin, type of material, conditions of use and are used according to the label instructions. Items without marking and labeling, as well as those labeled with a non-useful information, for example, „made from harmless plastic” are not the subject of this study. the wide spread of such items requires caution regarding their safety for consumers.

Research paper thumbnail of Comparative Analysis of Total Phenolic and Total Flavonoid Contents, Rutin, Tannins and Antioxidant Capacity in Apiaceae and Lamiaceae families

Indian Horticulture Journal, 2014

Comparative evaluations of the total phenolic and total flafonoid contents, rutin, tannins and an... more Comparative evaluations of the total phenolic and total flafonoid contents, rutin, tannins and antioxidant capacity to various herbal spices from the Apiaceae and Lamiaceae families to which belong: Foeniculum vulgare (Fennel), Anethum graveolens (Dill), Pimpinella anisum (Anise), Carum carvi (Caraway), Coriandrum sativum (Coriander), Melissa officialis (Lemon balm), Salvia officialis (Sage) and Mentha piperita (Mint) were carried out. The herb and seed spices were analyzed for their tannins content by titrimetric method; rutin was determined spectrophotometrically by using ammonium molybdate; the total phenolic contents were determined by using Folin-Ciocalteu assay; the total flavonoids were measured spectrophotometrically using the colorimetric reaction with aluminum (III) chloride. Antioxidant capacity was also analysed spectrophotometrically by a 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effect of the herbs and seeds. The total phenolic and flavonoid contents of the Foeniculum vulgare (Fennel) varied between 115.96 mg GAE/100g and 68.10 mg CE/100g. This content for the Coriandrum sativum (Coriander) is lower (between 17.04 mg GAE/100g and 11.10 mg CE/100g, respectively). The content of rutin and tannins of the Melissa officialis (Lemon baim) varied between 3.10% and 10.79%. It was found to be much higher than the rutin content of the Coriandrum sativu (Coriander) (between 0.99% and 0.42%, respectively). The highest radical scavenging effect was observed in the Foeniculum vulgare (Fennel) with IC50 of 113.19 mL/L. In the present study, the seed spices from the Apiacea family and the herb spices from Lamiaceae family to which belong: Foeniculum vulgare (Fennel), Anethum graveolens (Dill), Pimpinella anisum (Anise), Carum carvi (Caraway), Coriandrum sativum (Coriander), Melissa officialis (Lemon balm), Salvia officialis (Sage) and Mentha piperita (Mint) were studied as sources of natural antioxidants. The results from the antioxidant assays show that all seeds and herbs can act as radical scavengers to a certain extent.

Research paper thumbnail of Phthalate esters - spread, exposure and toxicity

Phthalates (phthalate esters) are a large group of chemical compounds - phthalic acid esters of t... more Phthalates (phthalate esters) are a large group of chemical compounds - phthalic acid esters of the general chemical structure obtained by the reaction of phthalic anhydride with alcohols. They are mainly used as plasticizers for plastic materials, in solvents, in cosmetics and in other applications. Phthalates are not covalently bonded to the molecules of the plastic, and they are easily separated from it by the processes of direct release, migration, evaporation, leaching, and abrasion. This is a prerequisite for their penetration into the human organisms in various ways - ingestion, inhalation and dermal absorption and even intravenously. The contribution of the different sources in the complex exposure to phthalates is unknown. Available toxicological studies are predominantly carried out on animals, but due to the similarities in the metabolism, phthalates are suspected to cause health problems in humans as well. Their acute toxicity is very low, but subchronic and chronic toxicity of phthalates and their metabolites are significant. In animal studies, phthalates have been identified as endocrine disruptors, causing a number of symptoms, called “phthalate syndrome,” mainly because of their effects on the male reproductive system. Studies in young girls have also shown a possible connection between the shortening of pregnancy, the development of breast cancer and exposure to phthalates. Exposure to phthalates relates to all age groups. In the absence of the relevant human studies is difficult to fully assess the risk of these compounds to the human health. In the European Union, legislative measures to restrict the content of phthalates in packaged food and beverages, children’s personal care products and toys are available, as well as measures to regulate the industrial use of phthalates. A clear statement of the ingredients of the products would allow consumers to choose the appropriate alternatives.

Research paper thumbnail of Phthalate__ampersandsignnbsp;Plasticizers__ampersandsignnbsp;and__ampersandsignnbsp;Safety__ampersandsignnbsp;of__ampersandsignnbsp;Toys__ampersandsignnbsp;-__ampersandsignnbsp;Problems__ampersandsignnbsp;and__ampersandsignnbsp;Perspectives

Research paper thumbnail of A New Challenge in the Academic World : Earning Real Money and Eminence by Paper Publishing

Jordan Journal of Biological Sciences, 2015

Research paper thumbnail of 3-Monochloro-1,2-propandiol (3-MCPD) in soy sauce from the Bulgarian market

Food Additives & Contaminants Part B-surveillance, Sep 1, 2013

The 3-monochloro-1,2-propandiol (3-MCPD) levels in soy sauces which contained hydrolysed vegetabl... more The 3-monochloro-1,2-propandiol (3-MCPD) levels in soy sauces which contained hydrolysed vegetable protein were evaluated for the Bulgarian market. For analysis of 3-MCPD, a gas chromatography-mass spectrometry (GC-MS) method was applied with a linear range of 0.03-2.00 μg mL⁻¹ and a limit of detection (LOD) of 2.3 μg kg⁻¹ and a limit of quantification (LOQ) of 3.4 μg kg⁻¹. At these levels, the standard deviation was 5.1%, with recoveries between 81% and 102%. The method was applied to the analysis of 21 samples of soy sauce from the Bulgarian market. Results ranged from 3.7 to 185.6 μg kg⁻¹. Soy sauces produced from hydrolysed soy protein contained higher levels of 3-MCPD than naturally fermented sauces. In 38.4% of samples of Bulgarian origin, the 3-MCPD content was above the EU limit of 20 μg kg⁻¹. In all analysed samples, 33.3% had a 3-MCPD content above the EU limit.

Research paper thumbnail of Rutin Content in Plant Products

Research paper thumbnail of Migration of Melamine and Formaldehyde from Kids' Bamboo Dinner Sets

Food and Environment Safety Journal, 2021

Research paper thumbnail of Aflatoxins - Analysis and Risk Management

Mintage Journal of Pharmaceutical and Medical Sciences, 2014

Objective : The purpose of this study is to analyze and assess the risk associated with the prese... more Objective : The purpose of this study is to analyze and assess the risk associated with the presence of aflatoxins in food and feed. Aflatoxins are produced by Aspergillus flavus and Aspergillus parasiticus and they are distributed worldwide. Conclusions: Aflatoxins are a potential danger for both animal and human health. Attention should be paid to the potentially dangerous synergistic or additive effects on animal health arising from the presence of more than one mycotoxin in feed. Given the ubiquity of mycotoxins in the world, is also necessary to develop an effective program of risk management, which will be crucial to reduce costs and economic losses in farms associated with the risk of pollution

Research paper thumbnail of Qualitative Analysis of Evidence Regarding Heroin and Impurities for the Purposes of Forensic Medicine (For the Period 2000-2012)

The use of chemical substances affecting the human psyche is as old as human history. Drug abuse ... more The use of chemical substances affecting the human psyche is as old as human history. Drug abuse is a problem which can be examined from many aspects-medical, legal, social, criminological, etc. The heart of the problem is the spread of drugs and related damage to young people, at the expense of material interests of the people involved in the system of distribution. In Bulgaria in the years after 1989 drug problem became a current issue. This work describes the results from the analysis of objects collected as evidence at crime scenes in cases of deaths of drug addicts or drug intake by living persons. The samples, after liquid / liquid extraction or directly dissolved in methanol, were analyzed by using GC with NPD detector and composition of the mixture was determined by comparison of retention times of the individual components using standard substances. After 2012, mass spectrometric identification was used. Substances and impurities, established in "street" heroin an...

Research paper thumbnail of HPLC determination of cinnarizine in workplace air

Research paper thumbnail of Short Communication DETERMINATION OF TANNINS CONTENT BY TITRIMETRIC METHOD FOR COMPARISON OF DIFFERENT PLANT SPECIES

Research paper thumbnail of Influence on aeration rate on performance characteristics of cattle manure composting with different Carbon sources used as bulking agents

A study on the effect of different aeration rates on the speed of composting process was carried ... more A study on the effect of different aeration rates on the speed of composting process was carried with mixtures of cattle manure and three different carbon sources (sawdust, rice pods and sunflower husks) under controlled laboratory conditions. The performance characteristics of composting process were evaluated in terms of the evolution of temperature (T), pH, electrical conductivity (EC) and organic matter (OM) content. The single, one-time filling of the composting reactors with the compost mixture showed better performance characteristics over the gradual filling of the reactors. The aeration for 15 min/hour at the rate of 50 L air/min provided sufficient quantity of O2 for aerobic conditions in the composting mixtures. The compost mixtures with sunflower husks maintained longer thermophilic phase with higher average daily temperatures in comparison to the other two bulking agents.

Research paper thumbnail of Determination of Dibutyl Phthalate (DBP), Benzyl Butyl Phthalate (BBP) and Bis (2-ETHYLHEXYL) Phthalate (Dehp) in Soft Plastic Toys and the First Survey of the Bulgarian Market

Phthalates are a large group of compounds with similar chemical structure widely used as plastici... more Phthalates are a large group of compounds with similar chemical structure widely used as plasticizers for plastics. They can easily be released from the polymer during usage and in this way enter the human body. Their adverse effect on health is known as "phthalate syndrome" and can impact children and adults alike. For children in particular, there is an additional potential risk of exposure to phthalates via toys intended for oral use. The Regulation (EC) No 1907/2006 (REACH) prohibits the use of bis (2-ethylhexyl) phthalate (DEHP), di butyl phthalate (DBP) and benzyl butyl phthalate (BBP) as a substance or constituent of preparations at concentrations higher than 0.1 % in the plasticized material meant to toys and childcare items. The aim of this article is to quantify the content of DEHP, DBP and BBP in soft toys intended for children up to 3 years of age, including toys designed to be placed in the mouth. A method consisting of an extraction procedure of phthalates fr...

Research paper thumbnail of Comparative Analysis of Total Phenolic and Total Flavonoid Contents, Rutin, Tannins and Antioxidant Capacity in Apiaceae and Lamiaceae families

Indian Horticulture Journal, 2014

Comparative evaluations of the total phenolic and total flafonoid contents, rutin, tannins and an... more Comparative evaluations of the total phenolic and total flafonoid contents, rutin, tannins and antioxidant capacity to various herbal spices from the Apiaceae and Lamiaceae families to which belong: Foeniculum vulgare (Fennel), Anethum graveolens (Dill), Pimpinella anisum (Anise), Carum carvi (Caraway), Coriandrum sativum (Coriander), Melissa officialis (Lemon balm), Salvia officialis (Sage) and Mentha piperita (Mint) were carried out. The herb and seed spices were analyzed for their tannins content by titrimetric method; rutin was determined spectrophotometrically by using ammonium molybdate; the total phenolic contents were determined by using Folin-Ciocalteu assay; the total flavonoids were measured spectrophotometrically using the colorimetric reaction with aluminum (III) chloride. Antioxidant capacity was also analysed spectrophotometrically by a 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effect of the herbs and seeds. The total phenolic and flavonoid contents of t...

Research paper thumbnail of Phthalate esters - spread, exposure and toxicity

Phthalates (phthalate esters) are a large group of chemical compounds - phthalic acid esters of t... more Phthalates (phthalate esters) are a large group of chemical compounds - phthalic acid esters of the general chemical structure obtained by the reaction of phthalic anhydride with alcohols. They are mainly used as plasticizers for plastic materials, in solvents, in cosmetics and in other applications. Phthalates are not covalently bonded to the molecules of the plastic, and they are easily separated from it by the processes of direct release, migration, evaporation, leaching, and abrasion. This is a prerequisite for their penetration into the human organisms in various ways - ingestion, inhalation and dermal absorption and even intravenously. The contribution of the different sources in the complex exposure to phthalates is unknown. Available toxicological studies are predominantly carried out on animals, but due to the similarities in the metabolism, phthalates are suspected to cause health problems in humans as well. Their acute toxicity is very low, but subchronic and chronic toxicity of phthalates and their metabolites are significant. In animal studies, phthalates have been identified as endocrine disruptors, causing a number of symptoms, called “phthalate syndrome,” mainly because of their effects on the male reproductive system. Studies in young girls have also shown a possible connection between the shortening of pregnancy, the development of breast cancer and exposure to phthalates. Exposure to phthalates relates to all age groups. In the absence of the relevant human studies is difficult to fully assess the risk of these compounds to the human health. In the European Union, legislative measures to restrict the content of phthalates in packaged food and beverages, children’s personal care products and toys are available, as well as measures to regulate the industrial use of phthalates. A clear statement of the ingredients of the products would allow consumers to choose the appropriate alternatives.

Research paper thumbnail of Soild-Liquid Extraction Kinetics of Total Phenolic, Total Flavonoid, Rutin and Tannin Contents in 50% Ethanol Extract of Cotinus coggygria

International Journal of Scientific & Engineering Research, 2016

phytoconstituents show that the dry leaves of Cotinus coggygria are rich in total phenols, total ... more phytoconstituents show that the dry leaves of Cotinus coggygria are rich in total phenols, total flavonoids, rutin and tannins. Solid–liquid extraction was carried out by 50% aqueous ethanol for 120 min, which gave concentration of total polyphenols and the findings of our present results are within good agreement with the other workers. . Index Terms— Rutin, Tannins, Total flavonoids, Total phenolics, Solid–liquid extraction, 50% aqueous ethanol extract of Bulgar-ian dry leaves of Cotinus coggygria