Determination of Chemical Composition of Turkish Propolis

2001 ◽  
Vol 56 (7-8) ◽  
pp. 666-668 ◽  
Author(s):  
Kadriye Sorkun ◽  
Banu Süer ◽  
Bekir Salih
Keyword(s):  
Chemical Composition ◽  
The Other ◽  
Aromatic Acids ◽  
Gas Chromatograph ◽  
Main Compound ◽  
Similar Chemical ◽  
Two Samples ◽  
Ethanol Extracts ◽  
Acid Esters

The aim of the present work is to study the chemical composition of Turkish propolis. Propolis samples were collected from different regions of Turkey (Bursa, Erzurum-Askale, Gumushane-Sogutagil and Trabzon-Caglayan) in 1999. Ethanol extracts of propolis (EEP) were prepared for chemical analysis, using gas chromatograph coupled with mass spectrometry (GC-MS). Our findings show that propolis samples from Trabzon and Gumushane region have a similar chemical composition. In both samples aromatic acids, aliphatic acids and their esters, and also ketone derivatives are the main compound groups. The chemical composition of the single sample that was collected from Erzurum region shows a very different pattern than the other two samples. In this propolis, the main compounds are aromatic acid esters and alcohols. However, it contains a high amount of amino acids compared to the other samples. The other samples collected from three different region of Bursa City are rich with flavavones, aromatic acids and their esters, terpenoids, flavones and ketones

scholarly journals Ability of NIR spectroscopy to predict meat chemical composition and quality – a review

2011 ◽  
Vol 49 (No. 11) ◽  
pp. 500-510 ◽  
Author(s):  
M. Prevolnik ◽  
M. Čandek-Potokar ◽  
D. Škorjanc
Keyword(s):  
Chemical Composition ◽  
Meat Quality ◽  
Quality Evaluation ◽  
Near Infrared ◽  
Nir Spectroscopy ◽  
The Other ◽  
Meat Composition ◽  
Feeding Regimes ◽  
Simultaneous Assessment

In contrast to conventional methods for the determination of meat chemical composition and quality, near infrared spectroscopy (NIRS) enables rapid, simple and simultaneous assessment of numerous meat properties. The present article is a review of published studies that examined the ability of NIRS to predict different meat properties. According to the published results, NIRS shows a great potential to replace the expensive and time-consuming chemical analysis of meat composition. On the other hand, NIRS is less accurate for predicting different attributes of meat quality. In view of meat quality evaluation, the use of NIRS appears more promising when categorizing meat into quality classes on the basis of meat quality traits for example discriminating between feeding regimes, discriminating fresh from frozen-thawed meat, discriminating strains, etc. The performance of NIRS to predict meat properties seems limited by the reliability of the method to which it is calibrated. Moreover, the use of NIRS may also be limited by the fact that it needs a laborious calibration for every purpose. In spite of that, NIRS is considered to be a very promising method for rapid meat evaluation.    

Comparative study of the ethanol extracts of six Acinos Miller species: chemical composition, antimicrobial and antioxidative activities

2020 ◽  
Vol 48 (1) ◽  
pp. 53-65
Author(s):  
Tatjana D. GOLUBOVIĆ ◽  
Gordana S. STOJANOVIĆ ◽  
Dušanka V. KITIĆ ◽  
Bojan K. ZLATKOVIĆ ◽  
Dragana R. PAVLOVIĆ ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
Salmonella Enteritidis ◽  
Ethanol Extract ◽  
Antimicrobial Activities ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Fungal Organisms ◽  
Ethanol Extracts

The ethanol extracts of selected Acinos Miller species were investigated in terms of chemical composition, antimicrobial and antioxidative activities. Qualitative and quantitative analyses of the extracts were performed using GC and GC-MS. Eighty-six constituents, accounting for 93.70-99.99% of the total composition of the extracts, were identified. The ethanol extracts of A. majoranifolius, A. suaveolens and A. alpinus were characterized by domination of monoterpenes, representing 85.03%, 57.39% and 28.02% of the total extracts, respectively. Fatty acids and their esters in the A. arvensis and A. graveolens extracts reached 28.97% and 30.75%. Also, n-alkanes were the major compounds found in A. hungaricus ethanol extract (30.98%). The extracts were characterized by determination of total polyphenols, flavonoids and tannins. Besides, the antioxidant activity of the investigated extracts was estimated by two assays: DPPH and FRAP test. The highest antioxidant activity was observed in the extract of A. alpinus which had high levels of all examined polyphenol classes. A disk diffusion method was employed for the determination of the antimicrobial activities of the ethanol extracts. Gram-positive: Bacillus subtilis, Sarcina lutea, Staphylococcus aureus, Clostridium pyogenes, Enterococcus sp., Micrococcus flavus; Gram-negative: Klebsiella pneumoniae, Pseudomonas aerugionsa, Salmonella enteritidis, Proteus vulgaris, Escherichia coli and fungal organisms: Aspergillus niger, Candida albicans and Saccharomyces cerevisiae were used as test microorganisms. The results of preliminary bioassay demonstrated that the A. alpinus ethanol extract could be a possible source of compounds with antioxidant and antimicrobial activity.

scholarly journals Influence of the processing method on the chemical composition and antioxidant activity of raspberries

2021 ◽  
pp. 388-392
Author(s):  
И.А. Громова ◽  
М.С. Воронина ◽  
Н.В. Макарова
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
Antioxidant Properties ◽  
Great Influence ◽  
Water Extract ◽  
Total Content ◽  
Waste Products ◽  
Fresh Frozen ◽  
Ethanol Extracts

Большое влияние на здоровье человека оказывают вещества, проявляющие антиоксидантный эффект, в значительной степени содержащиеся в ягодах малины и отходах сокового производства от данной ягоды, а именно свежезамороженной ягоде, свежевыжатом соке, водной вытяжке, сырых и высушенных выжимках и концентрированном соке. Целью работы стало изучение химического состава и антиоксидантной активности ягод малины и отходов сокового производства, наблюдение за изменением показателей исследуемых характеристик при механической и тепловой обработке ягод малины и выбор оптимального варианта. При проведении исследований были использованы следующие методы: определение общего содержания антоцианов; определение общего содержания фенольных соединений; определение общего содержания флавоноидов; определение антирадикальной активности; определение восстанавливающей силы; исследование антиоксидантных свойств с использованием модельной системы линолевой кислоты. Все методы по определению содержания антиоксидантов проводились на этанольных экстрактах. Установлено, что использование экстракции для ягод и отходов сокового производства позволяет более точно определить содержание исследуемых показателей. Выявлено, что наибольшая антиоксидантная активность 94,5-98,4 % отмечена в малине и водной вытяжке из нее. A great influence on human health is exerted by substances exhibiting an antioxidant effect, largely contained in raspberries and their juice waste products, specifically in fresh-frozen berries, fresh squeezed juice, water extract, raw and dried pomace and concentrated juice. The aim of the work was to study chemical composition and antioxidant activity of raspberries and their juice waste products, monitor changes in the parameters of the studied characteristics during mechanical and thermal processing of raspberries and select the optimal option. The following methods were used during the research: determination of the total content of anthocyanins; determination of the total content of phenolic compounds; determination of the total content of flavonoids; determination of antiradical activity; determination of regenerating power; study of antioxidant properties using a model system of linoleic acid. All methods for determining the content of antioxidants were carried out on ethanol extracts. It was established that using of extraction for berries and juice waste products made it possible to determine more precisely the content of the studied indicators. It was also revealed that the highest antioxidant activity of 94.5% - 98.4% was observed in raspberries and their water extract.

scholarly journals The Effect of Enantiomer Elution Order on the Determination of Minor Enantiomeric Impurity in Ketoprofen and Enantiomeric Purity Evaluation of Commercially Available Dexketoprofen Formulations

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5865
Author(s):  
Kenan Can Tok ◽  
Mehmet Gumustas ◽  
Giorgi Jibuti ◽  
Halit Sinan Suzen ◽  
Sibel A. Ozkan ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Method Validation ◽  
Chiral Selector ◽  
Enantiomeric Purity ◽  
The Other ◽  
Elution Order ◽  
Validation Parameters ◽  
Purity Evaluation

In a recent study, opposite enantiomer elution order was observed for ketoprofen enantiomers on two amylose-phenylcarbamate-based chiral columns with the same chemical composition of the chiral selector but in one case with coated while in the other with an immobilized chiral selector. In the present study, the influence of this uncommon effect on method validation parameters for the determination of minor enantiomeric impurity in dexketoprofen was studied. The validated methods with two alternative elution orders for enantiomers were applied for the evaluation of enantiomeric impurity in six marketed dexketoprofen formulations from various vendors. In most of these formulations except one the content of enantiomeric impurity exceeded 0.1% (w/w).

Pericline and acline-A twins in the acid plagioclases

1930 ◽  
Vol 22 (128) ◽  
pp. 225-230 ◽  
Author(s):  
F. Coles Phillips
Keyword(s):  
Chemical Composition ◽  
The Other ◽  
Suitable Material ◽  
The Face

The orientation of the ‘rhombic section’, the composition-plane of the pericline twin, in the plagioclase felspars as an index of the chemical composition of the felspar waJ first utilized by G. yore Rath, who measured the gngle a on the face (010) between the trace of the composition-plane and the edge [010,001]. Duparc and Reinhard, in their comprehensive work on the determination of the plagioclases, quote two series of values for this angle, one due to Wiilfmg and the other to Becke. They comment on the discordance between the two series, most marked at the acid end, and add that they did not then possess suitable material for critical determinations on their own account. Wülfing's values are given in the form of a curve based on data assembled by Schmidt, and those of Becke were first given in a paper on the felspars in crystalline schists.

Purified preparations of tobacco necrosis virus (Nicotiana virus II)

Parasitology ◽  
1938 ◽  
Vol 30 (4) ◽  
pp. 543-551 ◽  
Author(s):  
N. W. Pirie ◽  
K. M. Smith ◽  
E. T. C. Spooner ◽  
W. D. McClement
Keyword(s):  
Chemical Composition ◽  
Principal Component ◽  
The Other ◽  
Tobacco Necrosis Virus ◽  
Necrosis Virus ◽  
Tobacco Plants ◽  
Sedimentation Constant ◽  
Similar Chemical ◽  
The Difference ◽  
The One

Two nucleoproteins with similar chemical composition have been isolated from the leaves of tobacco plants infected with tobacco necrosis virus. One of these is crystalline and has a sedimentation constant of 130 × 10−13; the other is amorphous and its principal component has a sedimentation constant of 58 × lO−13.Each preparation will infect plants at a dilution of 1 in 108 and will precipitate specifically with antiserum at a dilution of 1 in 3·2 × 105.The nature of the difference between preparations in the two states is obscure and it has not proved possible to convert the one into the other.

scholarly journals DETERMINATION OF THE CHEMICAL COMPOSITION OF GRAPE SEED POWDERS BY GC-MS ANALYSIS

2018 ◽  
Vol 6 ◽  
pp. 3-8
Author(s):  
Olena Gorodyska ◽  
Nataliya Grevtseva ◽  
Olga Samokhvalova ◽  
Sergey Gubsky
Keyword(s):  
Fatty Acids ◽  
Chemical Composition ◽  
Experimental Studies ◽  
Natural Antioxidants ◽  
Grape Seed ◽  
Aromatic Acids ◽  
Phenol Compounds ◽  
Different Origin ◽  
Water Alcohol

Substantiation of the expedience of using of natural antioxidants for inhibiting of oxidative and hydrolytic rancidity in confectionary industry is an urgent direction. The offered way of solving the problem is to use a fat-less grape seed powder, a product, obtained as wastes of vine-making as a source of antioxidants. For this aim, there were realized experimental studies of water-alcohol extracts (ethanol, isopropanol) by the method of gas chromatography with mass-spectroscopic detection (CG-MS) of the chemical composition of grape seed powders under industrial conditions. The obtained data allowed to establish that the studied extracts contain an essential amount of phenol compounds of the different origin: aromatic acids – gallic and egallic acids; resveratrol; flavonoids – quercetin and its derivatives, catechine, epicatechine, campferol and others alongside with esters of fatty acids. These components are strong antioxidants, and their introduction to a grape seed powder must favor inhibition of the oxidizing process of fats in fat-containing confectionary products, so increasing shelf-life of products.

The determination of the crystallinity in glass-ceramic materials by the method of Ruland

1983 ◽  
Vol 16 (2) ◽  
pp. 274-276 ◽  
Author(s):  
C. G. Vonk ◽  
G. Fagherazzi
Keyword(s):  
Chemical Composition ◽  
Glass Ceramic ◽  
Ceramic Materials ◽  
Acta Cryst ◽  
X Ray ◽  
Glass Ceramic Materials ◽  
Two Samples ◽  
Ray Methods

The method of Ruland [Acta Cryst. (1961). 14, 1180–1185] for the determination of crystallinity has been modified in order to take account of a difference in chemical composition of the crystallized and non-crystallized fractions, such as occurs in glass-ceramic materials. Application to two samples leads to higher crystallinities than found by other X-ray methods, and shows a large increase of disorder with decreasing crystallinity.

The spectrochemical determination of feldspars within the field microcline-albite—labradorite

1964 ◽  
Vol 33 (264) ◽  
pp. 790-798 ◽  
Author(s):  
W. E. Fraser ◽  
G. Downie
Keyword(s):  
Chemical Composition ◽  
The Other ◽  
Visual Estimation ◽  
Quartz Spectrograph

SummaryTwo spectrochemical methods of feldspar determination are described: one based on the flame spectrophotometer; the other on the quartz spectrograph. For the first method, unknown feldspars are dissolved in a mixture of hydrofluoric and perchloric acids and diluted to 1 : 104. Percentages of Or and An are determined by comparison with dissolved feldspar standards at the same dilution; percentages of Ab are estimated by difference. For the second method, unknown feldspars are burned, unadulterated, in the cathode of the spectrograph arc and a visual estimation is made of the intensities of the following lines: Na5688, Na5683, Ca4455, Ca4435, Ca4425, K4047, K4044, Ca3644, K3447, Na3303, Na3302, and Ca3159. The estimated intensities are then substituted in two empirically determined functions:(ICa4455+ICa4435+ICa4255+ICa3644+ICa3159)−4/3(INa5688+INa5683+INa3303+INa3302)and (3INa5688+3INa5683+2INa3303+INa3302)−43(4IK4047+3IK4044+2IK3447) .From the algebraic values of these two functions, the compositions of the unknown feldspars, expressed as percentages of Or, Ab, and An, are read directly from a chart based on results obtained from feldspar standards of known chemical composition.

Sign in / Sign up

Export Citation Format

Share Document