Comparison of Traditional and Industrial Sausages - Baranjski Kulen and Kulenova Seka Using Comprehensive Proteome, Peptidome and Metabolome Techniques

Research background. Baranjski kulen is one of the most popular fermented meat sausages originating from Croatia. It has protected geographical indication, and is traditionally produced in the Baranja region of Croatia. Kulenova seka is a fermented sausage very similar to Baranjski kulen, but it has a different caliber and consequently, a shorter time of production. In recent decades, due to the high demand and popularity of these products, industrially produced Baranjski kulen and Kulenova seka have become available on the market. This work aims to identify specific characteristics of traditional and industrial sausages, Baranjski kulen and Kulenova seka on proteome, peptidome and metabolome level which could potentially lead to better optimization of the industrial production process in order to obtain an equivalent to the traditional product. Experimental approach. Protein profiles of Baranjski kulen and Kulenova seka (traditional and industrial) were analysed using two-dimensional gel electrophoresis followed by differential display analysis and protein identification using mass spectrometry. Peptidomics profiling analysis was performed via liquid chromatography-tandem mass spectrometry. Furthermore, aroma profiles were investigated via headspace solid phase microextraction and gas chromatography-mass spectrometry. Results and conclusions. The major identified characteristics of each product were: industrial Baranjski kulen - specific degradation of MYH1 and TITIN, overabundance of stress-related proteins and increased phenylalanine degradation; traditional Baranjski kulen - decreased concentration of phenylalanine and overabundance of ALDOA and CAH3; industrial Kulenova seka - specific MYH4 and HBA degradation process; traditional Kulenova seka - overabundance of DPYD and MYL1, degradation of ALBU and MYG, decreased concentrations of almost all free amino acids and increased amounts of smoke derived volatile compounds. Novelty and scientific contribution. In this preliminary communication, the first insights into protein degradation processes and generation of peptides, free amino acids and aroma compounds of industrial and traditional Baranjski kulen and Kulenova seka are presented. Although further research is needed to draw general conclusions, the specific profile of proteins, peptides, amino acids, and volatile compounds represents the first step in the industrial production of sausages that meet the characteristics of traditional flavour.

Study of Epilobium angustifolium L. amino acids content by HPLC method

The use of plant raw materials is one of the areas of modern pharmaceutical science in the production of herbal drugs. The genus Epilobium counts more than 200 species, many species of which are used in traditional medicine. Among the Epilobium species, Epilobium angustifolium is one of the well-known medicinal plants which have been used worldwide in habitual medicine. There is insufficient information in the literature on the biologically active substances of Epilobium angustifolium L. The presence of three major polyphenol groups: phenolic acids, flavonoids, and ellagitannins were identified in E. angustifolium extracts. Traditionally, the infusion of leaves of this plant could be useful for headaches, cold and gastrointestinal disorder. The Epilobium angustifolium L. as an insufficiently studied plant is a promising object of study, including amino acids composition. To assess the relationship between the production of primary metabolites and their possible therapeutic properties, we analyzed the amino acid profile of the plant Epilobium angustifolium used in traditional medicine. The study of compounds generated by plants as a result of defense mechanisms permits an understanding of the molecular mechanism involved in their medicinal properties. The aim. Thus, the aim of the study was to conduct an HPLC analysis of the amino acids of E. angustifolium to establish the prospects for the use of the raw materials in medical and pharmaceutical practice. The results of the current study will be used in further breeding programs aimed to obtain an industrial form of E. angustifolium suitable for pharmaceutical and food applications. Materials and methods. The determination of amino acids composition of Epilobium angustifolium was conducted using Agilent 1200 (Agilent Technologies, USA). Results. The HPLC method identified sixteen free amino acids and seventeen bound amino acids in the Epilobium angustifolium herb. The studies have shown that Epilobium angustifolium L. herb is mainly composed of free amino acids such as L-phenylalanine (1.65 µg/mg), L-glutamic acid (1.51 µg/mg), L-arginine (1.24 µg/mg), L-alanine (0.98 µg/mg) and L-aspartic acid (0.57 µg/mg), which were presents in the greatest amount. The dominant bound amino acids in the studied raw material were L-glutamic acid, L-aspartic acid, L-leucine, and L-alanine, the content of which was 32.37 µg/mg, 10.59 µg/mg, 8.70 µg/mg, and 6.22 µg/mg respectively. Conclusions. Using the HPLC method determined the amino acids in the herb of Epilobium angustifolium L. The concentrations of L-aspartic acid, L-glutamic acid, L-arginine, L-alanine and L-phenylalanine are predominate among free and bound amino acids in the Epilobium angustifolium L. herb. The result shows that Epilobium angustifolium L. is the source of amino acids, so the use of this plant raw material for new remedies is possible in the future

Macronutrients and essential amino acids on digestive process of the freshwater teleost Matrinxã

The objective of this work was to evaluate the effect of macronutrients and essential amino acids on digestive process of the freshwater teleost Matrinxã (Brycon amazonicus). Juveniles were fed with diets containing starch plus free amino acids or oil plus free amino acids for 15 days. These fish were compared with others fed with diets containing starch or oil without addition of free amino acids. After the experimental span, 12 fish from each treatment were randomly sampled to collect stomach, pyloric cecum, anterior and posterior intestine for assaying digestive enzymes activity. Increase of gastric proteolysis due to dietary amino acids were observed. Amylolytic, proteolytic and lipolytic activities in intestine sections were also positive related to dietary amino acids. However, proteolytic and lipolytic activities in pyloric cecum were not responsive to dietary changes. Moreover, the absence of starch in the diets resulted in decrease of amylolysis, and very low levels of oil did not change the lipolytic activity. In conclusion, activities of amylase, protease and lipase of Matrinxãare selectively responsive to addition of free essential amino acids concerning the gut section.

Role of Nitrogen Compounds in Forming the Quality of Red Sparkling Wine

В технологии игристых вин азотистые соединения, в том числе их концентрация и качественный состав, играют существенную роль на всех этапах производственного процесса. Цель работы состояла в исследовании изменения азотсодержащих соединений в процессе вторичного брожения и их влияния на качественные характеристики красного игристого вина. В качестве объектов исследования в работе использованы пять промышленных образцов сортовых виноматериалов, соответствующих требованиям нормативной документации по физико-химическим и органолептическим показателям, и пять купажей, составленных из этих виноматериалов, а также опытные образцы игристых вин, полученные в результате вторичного брожения в бутылках. Определение массовой концентрации аминного азота проводили методом йодометрического титрования, аммиачного азота - диффузионным методом. Исследование качественного состава и концентрации аминокислот проводили с использованием ВЭЖХ на приборе «Аgilent Technologies 1200 Series» (Agilent, США). Установлено, что концентрация аммиачного азота в исследованных образцах варьировала от 13,4 до 29,7 мг/дм3, аминного азота - от 53,2 до 364,0 мг/дм3, свободных аминокислот - от 267,4 до 615,4 мг/дм3. Показано, что в результате вторичного брожения снижается суммарная концентрация аминокислот, причем наиболее сильно - в образцах с низким содержанием неорганического азота менее 20,0 мг/дм3. В образцах с высоким содержанием фенольных веществ снижение концентрации аминокислот происходило за счет образования с ними комплексных соединений. Показано, что состав азотистых соединений и соотношение свободных аминокислот в исходных виноматериалах оказывает влияние на образование отдельных ароматобразующих летучих компонентов и формирование типичных свойств красного игристого вина. Рекомендовано использовать показатели массовой концентрации аминного и аммиачного азота, а также состав и концентрацию свободных аминокислот в качестве дополнительных критериев оценки виноматериалов для выработки высококачественных красных игристых вин. In the technology of sparkling wines, nitrogenous compounds, including their concentration and qualitative composition, play an essential role at all stages of the production process. The aim of the work was to study the changes in nitrogen-containing compounds during secondary fermentation and their effect on the qualitative characteristics of red sparkling wine. As objects of research, five industrial samples of varietal wine materials that meet the requirements of regulatory documentation on physico-chemical and organoleptic indicators, and five blends made up of these wine materials, as well as experimental samples of sparkling wines obtained as a result of secondary fermentation in bottles, were used in the work. Determination of the mass concentration of amine nitrogen was carried out by iodometric titration, ammonia nitrogen - by diffusion method. The study of the qualitative composition and concentration of amino acids was carried out using HPLC on the device «Agilent Technologies 1200 Series» (Agilent, USA). It was found that the concentration of ammonia nitrogen in the studied samples varied from 13.4 to 29.7 mg/dm3, amine nitrogen - from 53.2 to 364.0 mg/dm3, free amino acids - from 267.4 to 615.4 mg/dm3. It is shown that as a result of secondary fermentation, the total concentration of amino acids decreases, and most strongly in samples with a low content of inorganic nitrogen less than 20.0 mg /dm3. In samples with a high content of phenolic substances, the concentration of amino acids decreased due to the formation of complex compounds with them. It is shown that the composition of nitrogenous compounds and the ratio of free amino acids in the initial wine materials influence the formation of individual aroma-forming volatile components and the formation of typical properties of red sparkling wine. It is recommended to use indicators of the mass concentration of amine and ammonia nitrogen, as well as the composition and concentration of free amino acids as additional criteria for evaluating wine materials for the production of high-quality red sparkling wines.

Antioxidant Potential of Flower Extracts from Centaurea spp. Depends on Their Content of Phenolics, Flavonoids and Free Amino Acids

Scientists intensely search for new sources of antioxidants, perceived as important health-promoting agents. Some species of the large genus Centaurea provide raw materials for the pharmaceutical and cosmetic industries, as well as produce edible flowers. This is the first study that determines the content of total polyphenols, flavonoids, reducing sugars, free amino acids and the antioxidant potential in the flower extracts of C. nigra L., C. orientalis L. and C. phrygia L. The total polyphenol and flavonoid content is the highest in the extract of C. orientalis, and the lowest in that of C. phrygia. Similarly, C. orientalis shows the greatest scavenging activity on DPPH (1,1-diphenyl-2-picryl-hydrazyl), ABTS [2,2′-azobis(3-ethylbenzothiazoline-6-sulfonate)] and Fe3+ reducing power assays, whereas the lowest activity is found for C. phrygia. The highest content of reducing sugars is found in C. nigra, while C. orientalis has the highest levels of free amino acids. We find a strong positive correlation between total phenolics and flavonoids and the antioxidant capacity of all three Centaurea species. Moreover, the content of free amino acids strongly and positively correlates with the levels of total phenolics and flavonoids, antioxidant activity assessed by DPPH and ABTS assays and Fe3+ reducing power. Summing up, C. orientalis exhibits the strongest antioxidant potential of the investigated Centaurea species. This species could potentially be a natural source of antioxidant substances for the pharmacy, cosmetics and food industries. The content of free amino acids may be used as a marker of the antioxidant status of Centaurea species.

A Quadratic Regression Model to Quantify Plantation Soil Factors That Affect Tea Quality

Tea components (tea polyphenols, catechins, free amino acids, and caffeine) are the key factors affecting the quality of green tea. This study aimed to relate key biochemical substances in tea to soil nutrient composition and the effectiveness of fertilization. Seventy tea samples and their corresponding plantation soil were randomly collected from Xinyang City, China. The catechins, free amino acids, and caffeine in tea were examined, as well as the soil pH, nitrate (NO3--N), ammonium (NH4+-N), available phosphorus (AP), available potassium (AK), and soil organic matter (SOM). The ordinary kriging was employed to visualize the spatial variation characteristic by ArcGIS. A quadratic regression model was used to analyze the effects of the soil environment on the tea. The results showed that the soil pH of the study area was suitable for cultivating tea plants. The relationship between soil pH and tea polyphenols and catechins presented the U-shape curve, whereas the soil pH and NH4+-N and the free amino acids, the soil pH, and caffeine presented the inverted U-shape curve. Soil management measures could be implemented to control the soil environment for improving the tea quality. The combination of the macro metrological model with individual experimentation could help to analyze the detailed influence mechanisms of environmental factors on plant physiological processes.