SIMULTANEOUS DETERMINATION OF FREE AMINO ACIDS, L-CARNOSINE, PURINE, PYRIMIDINE, AND NUCLEOSIDES IN MEAT BY LIQUID CHROMATOGRAPHY/SINGLE QUADRUPOLE MASS SPECTROMETRY

<div><p>A novel approach to single-run determination of 25 free amino acids, L-carnosine, 4 nitrogen bases (purine and pyrimidine), and 5 nucleosides in unpurified biological samples is reported. The analytes were extracted from the sample, derivatized with dansyl chloride, and analyzed using RP-HPLC-DAD-ESI-MS. The reported method features high sensitivity (LOQs in 5–10 ng mL⁻¹ range), wide linearity range with <i>r</i> > 0.94, and high precision (intra-day RSD within the 0.1–4.2% range). Analyte average recovery coefficient was in the 70.1–111.3% range. The method was used to determine levels of free amino acids, L-carnosine, nitrogen bases, and nucleosides in beef (strip loin). Evolution of concentrations of the studied compounds during meat storage processes (vacuum packing, cold storage) was also investigated.</p> </div

Application of hydrophilic interaction liquid chromatography for the quantification of succinylcholine in Active Pharmaceutical Ingredient and medicinal product. Identification of new impurities of succinylcholine chloride

A new method, using hydrophilic interaction chromatography (HILIC), for quantification of succinylcholine and impurities in Active Pharmaceutical Ingredient (API), as well as in the medicinal product, was developed. Additionally, the new impurities in API were discovered using ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF) technique. The substances were quantified with the application of a UV detector (λ = 214 nm). Chromatographic separation was performed isocratically with the application of 30% phosphate buffer (pH 4,0; 0.05 M) in ACN as a mobile phase. A major feature of the developed method is a very high resolution (Rs > 3), between succinylcholine and its main impurity - succinylmonocholine, whereas the width of peak bands does not exceed 0.7 min. A low value of limits of detection (LOD) were obtained for succinic acid, succinylmonocholine and for succinylcholine, which amounted to 2.4, 6.0 and 11.5 μg ml−1, respectively. Another feature of the developed method is linearity in a very wide range of concentrations: 7.3 μg ml−1 – 670 μg ml−1 amounting to R2 = 0.999. The recovery provided by this method at three different fortification levels for all analytes remained within the following range: 95.7 – 98.9 %. Intra-day and inter-day precision remained within the following range: 1.0 – 5.9 % coefficient of variation (CV), whereas accuracy within the range: −1.3 – 6.3. The developed method of hydrophilic interactions made it possible to quantify two new impurities, probably originating from the synthesis of an API: [2-(trimethylaminium)ethyl]-[2ʹ-(trimethylaminium)vinyl] succinate and [2-(dimethylamino)etyl]-[2ʹ-(trimethylaminium)etyl] succinate, which were identified and described for the first time. In addition, a physicochemical form of peak doublet described in the USP as impurities was studied and it was demonstrated that these peaks are the result of the specific physicochemical interactions in ion pair chromatography

Analysis of Menaquinone-7 Content and Impurities in Oil and Non-Oil Dietary Supplements

Rapid, global technological development has caused the food industry to use concentrated food component sources like dietary supplements ever more commonly as part of the human diet. This study analysed the menaquinone-7 (MK-7) content of dietary supplements in oil capsule and hard tablet forms. A novel method for separating and measuring geometric isomers of MK-7 in dietary supplements was developed and validated. Eleven different isomers of cis/trans- menaquinone-7 were identified. Identification of cis/trans isomers was performed by combination of HPLC, UPLC and HRMS-QTOF detection, whereas their quantities were determined by DAD detection. The content of menaquinone impurities was ascertained, including cis/trans- menaquinone-6 isomers (5.5&ndash;16.9 &micro;g per tablet/capsule) and cis/trans-menaquinone-7 isomers (70.9&ndash;218.7 &micro;g tablet/capsule), which were most likely formed during the chemical synthesis of the menaquinone-7. The all-trans MK-7 content was lower than the isomeric form and often lower than what the labels declared. A new method of quantification, developed and validated for menaquinones in oil capsules, provided on average 90% recovery and a limit of quantification (LOQ) of approximately 1 &micro;g mL&minus;1

Synthesis of Oxidized 3β,3′β-Disteryl Ethers and Search after High-Temperature Treatment of Sterol-Rich Samples

It was proven that sterols subjected to high-temperature treatment can be concatenated, which results in polymeric structures, e.g., 3β,3′β-disteryl ethers. However, it was also proven that due to increased temperature in oxygen-containing conditions, sterols can undergo various oxidation reactions. This study aimed to prove the existence and perform quantitative analysis of oxidized 3β,3′β-disteryl ethers, which could form during high-temperature treatment of sterol-rich samples. Samples were heated at 180, 200 and 220 °C for 0.5 to 4 h. Quantitative analyses of the oxidized 3β,3′β-disteryl ethers were performed with liquid extraction, solid-phase extraction and liquid chromatography coupled with mass spectrometry. Additionally, to perform this analysis, the appropriate standards of all oxidized 3β,3′β-disteryl ethers were prepared. Eighteen various oxidized 3β,3′β-disteryl ethers (derivatives of 3β,3′β-dicholesteryl ether, 3β,3′β-disitosteryl ether and 3β,3′β-distigmasteryl ether) were prepared. Additionally, the influence of metal compounds on the mechanism of ether formation at high temperatures was investigated

α- and β-Carotene Stability During Storage of Microspheres Obtained from Spray-Dried Microencapsulation Technology

This study was aimed at comparing the stability of carotenes (α- and β-carotene) in oil solutions with their stability when spray-dried encapsulation is applied. The carotenes were isolated from carrot. A storage test was subsequently performed. The stability of carotenes in oil solutions was determined with the HPLC method. The color of the samples was also analyzed. The oil solutions of carotenes were microencapsulated with the spray-drying method. A mixture of gum Arabic and maltodextrin was used as a matrix

Effect of Various Drying Methods on Physicochemical and Bioactive Properties of Quince Fruit (<i>Cydonia oblonga</i> Mill.)

The quince (Cydonia oblonga Mill.), due to its valuable bioactive properties and high health-promoting potential, is becoming more and more popular for the prevention of many free radical diseases. Due to the high hardness of the flesh and its bitterness and astringency, quinces are rarely eaten in the form of fresh fruit, and much more often in the form of various preserves, or in the form of dried additives, e.g., to the tea. Heat treatment (including drying) affects not only the content of bioactive compounds, but also the antioxidant activity and organoleptic characteristics. Therefore, this study examined the physicochemical properties of quinces (including the content of dry matter, soluble solids (°Brix), water activity (aw), pH, total acidity and color changes (in the L*a*b* space)), fresh and dried by various methods, i.e., freeze-drying and convection at 50 °C and 70 °C. In addition, the effect of various drying conditions on the content of selected bioactive compounds, i.e., tannins, carotenoids, flavonoids, phenolic acids and total polyphenols, was assessed, as well as the antioxidant properties of fresh quinces and quinces dried under different conditions. Based on the research, it can be concluded that the applied processes of the dehydration of quinces significantly changed both the physicochemical properties and the content of biologically active ingredients and antioxidant properties, while both fresh and dried fruit provide nutritionally valuable bioactive ingredients and show high antioxidant potential. Considering the great taste and bioactive qualities of the common quince, introducing it to the daily diet, whether in a traditional form (dried fruit, fruit preserves) or in the form of dietary supplements, can be an important element in the prevention of many civilization diseases

Content of Health-Promoting Fatty Acids in Commercial Sheep, Cow and Goat Cheeses

The study aimed to examine samples of different market original sheep cow and goat cheeses, in respect of the content and profile of FA with special emphasis on health-promoting FA. The content of fatty acids in the examined cheeses was highly differentiated and depended on the sort and type of cheese. The content of fatty acid groups in milk fat varied within the limits: SFA, 55.2–67.2%; SCSFA, 10.9–23.4%; BCFA, 1.6–2.9%; MUFA, 15.2–23.4%; PUFA, 1.9–4.3%; trans-MUFA, 1.8–6.0%; and CLA, 1.0–3.1%. From among the examined cheeses, the seasonal sheep cheeses (Oscypek) and mountain cow cheeses were characterized by the highest content of health-promoting fatty acids. The content of health-promoting fatty acids in the fat fraction of these cheeses was CLA 2.1–3.1%, trans-MUFA 3.5–6%, BCFA 2.7–2.9%, and SCSFA 12–18%

Changes in Physicochemical and Bioactive Properties of Quince (<i>Cydonia oblonga</i> Mill.) and Its Products

Quince (Cydonia oblonga Miller) is a plant that is commonly cultivated around the world, known for centuries for its valuable nutritional and healing properties. Although quince fruit are extremely aromatic, due to their high hardness and sour, astringent, and bitter taste, they are not suitable for direct consumption in an unprocessed form. However, they are an important raw material in fruit processing, e.g., in the production of jams, jellies, and juices. Quince fruits fall under the category of temperate fruits, so their shelf life can be predicted. Considering that technological processing affects not only the organoleptic properties and shelf life but also the functional properties of fruits, the aim of this research was to determine the impact of various types of technological treatments on the physicochemical and bioactive properties of quince fruit. In fresh, boiled, and fried fruits and in freshly squeezed quince fruit juice, basic parameters, such as the content of dry matter, moisture, soluble solids (°Brix), pH, total acidity, water activity, and color parameters (L*a*b*) were determined. The content of key bioactive ingredients, i.e., tannins, carotenoids, flavonoids, phenolic acids, and total polyphenols, was also determined, as well as the antioxidant activity of raw and technologically processed (cooked, fried, and squeezed) quince fruits. The conducted research showed that fresh quince fruit and processed quince products can be a very good source of bioactive ingredients in the diet, such as tannins (3.64 ± 0.06 mg/100 g in fresh fruit; from 2.22 ± 0.02 mg/100 g to 5.59 ± 0.15 g/100 g in products), carotenoids (44.98 ± 0.18 mg/100 g in fresh fruit; from 141.88 ± 0.62 mg/100 g to 166.12 ± 0.62 mg/100 g in products), and polyphenolic compounds (246.98 ± 6.76 mg GAE/100 g in fresh fruit; from 364.53 ± 3.76 mg/100 g to 674.21 ± 4.49 mg/100 g in products). Quince fruit and quince products are also characterized by high antioxidant properties (452.41 ± 6.50 µM TEAC/100 g in fresh fruit; 520.78 ± 8.56 µM TEAC/100 g to 916.16 ± 6.55 µM TEAC/100 g in products). The choice of appropriate technological processing for the quince fruit may allow producers to obtain high-quality fruit preserves and act a starting point for the development of functional products with the addition of quince fruit in its various forms, with high health-promoting values and a wide range of applications in both the food and pharmaceutical industries