Potravinarstvo Slovak Journal of Food Sciences
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Fruit red colorants impact on the antiradical activity determined by DPPH method
Get PDFThis work is focused on the determination of antiradical activity (ARA) by the method of free radical scavenging of 2,2-Diphenyl-1-picrylhydrazyl (DPPH). Since the DPPH solution is intense purple-coloured and absorbs at a wavelength of 517 nm, similar to the anthocyanin colorants of fruits, the modification of the method examined the effect of the colour of the sample extracts on the result of the ARA determination. Statistical evaluation of the results of the analyses using Youden's graphing method revealed that the two compared method adjustments gave consistent results over the observed range of antiradical activity. It also showed that there was no statistically significant difference between the mean ARA values obtained by the two treatments. Investigation of the effect of the evaluated fruit components revealed a strong correlation between the content of ascorbic acid and ARA in samples containing no anthocyanin colorants. For the fruit samples studied, ARA values showed a strong correlation with polyphenol content
Assessment of flavonoids and phenolic compound accumulation in invasive Solidago canadensis L. in Slovakia
Get PDFSolidago canadensis L. was introduced to Europe as an ornamental plant from North America in 1645 and began to spread during the XIX-XX centuries. Nowadays the species is considered the most aggressive invasive species. On the other hand, S. canadensis is considered to be a medicinal plant. The raw material known as Herba Solidaginis includes herbs of S. canadensis, S. gigantea, and S. virgaurea. These species are known for their diuretic, anti-inflammatory, antimicrobial, antioxidant, antispasmodic properties. The purpose of our study was to analyze the chemical compounds and some biological properties of S. canadensis, growing in Slovakia, to evaluate its therapeutic potential. The total phenolic content (TPC) of the extracts from aerial parts of S. canadensis was determined by the Folin-Ciocalteu method. The evaluation of total flavonoid content (TFC) was performed by using a spectrophotometric method. The flavonoids content was expressed as rutin equivalents (mg REs) per g DW vegetal product. The phytochemical profile of S. canadensis extracts was assessed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The radical scavenging activity of samples was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Reducing power of extracts was determined by the phosphomolybdenum method. Total phenolic contents (TPC) and total flavonoid contents (TFC) of the extracts varied from 204.19 to 293.43 mg GAE.g-1 DW, and 64.99 – 175.25 g QE.g-1 DW, respectively; the best results were obtained for ethanol extract. Some phenolic compounds were identified by HPLC with significant amounts of rutin (211.20 µg.mL-1), quercetin (122.08 µg.mL-1), quercitrin (102.50 µg.mL-1) and chlorogenic acid (147.00 µg.mL-1). The DPPH values in the inflorescences were higher than in the leaves: the antioxidant activity of leaf extracts was in the range from 5.34 to 17.16 mg TE.g-1, for inflorescences, this parameter ranged from 6.09 to 19.87 mg TE.g-1. The high total phenolic compounds and flavonoids can be used as a valuable source of phytochemicals in herbal remedies. Our study of S. canadensis, growing in Slovakia, shows the promising potential that can be evaluated as an effective antioxidant and antimicrobial agent in herbal medicines
The study of selected components of grape and fruit wines
Get PDFThis study aimed to compare chemical properties, in terms of the content of volatile substances, antioxidant compounds, and antioxidant activity (AOA), in samples of fruit and grape wines. For this purpose, the following types of wine were selected, namely fruit wines (apple, strawberry, and elderberry) and grape wines (Müller-Thurgau, St. Lawrence Rosé, and Blue Portugal). Basic analyses of fruit and grape wines were conducted by using the ALPHA method and volatile substances in wines were determined by the GS/MC method. The antioxidant content and AOA were estimated by spectrophotometry, using two types of DPPH method. The results of the experiment showed that the highest values of antioxidant compounds (anthocyanins and flavanols) were found in the samples of Blue Portugal wine and elderberry wine. Significant differences were determined among the wines in antioxidant content, which may have been influenced by the production technology. The results showed that the alcohol content of the wines ranged from 10.99% to 19.49% vol. The highest alcohol content was measured in the elderberry wine samples and the lowest in those of the apple wine. The strawberry wine had the highest titratable acid content, which corresponded to a pH of 3.38. The lowest content was measured in the apple wine samples. Due to the higher acid content of the strawberry wine, a higher residual sugar level of 46.9 g.L-1 was obtained. We noted that the red fruit wines contained a higher proportion of valuable bioactive substances than white grape wines. Wines with superior sensory properties did not contain higher levels of antioxidants or higher AOA. The research results can provide a helpful reference for the widespread use of grape and fruit wines in medical, nutritional, and other fields
Patin (Pangasius hypophthalmus) fish protein concentrate alters insulin-like growth factor (IGF)-1 and igf binding protein (IGFBP)-3 level of sprague dawley neonate rats-induced malnutrition
Get PDFMalnutrition is caused by inadequate protein intake and affects growth factor. High protein from patin (Pangasius hypophthalmus) fish is a well-known protein source. This study aims to investigate the effect of patin fish protein concentrate (PFPC) in the IGF-1 and IGFBP-3 level of Sprague Dawley (SD) neonate rats-induced malnutrition. Thirty male SD neonate rats were divided randomly into five groups, namely normal control (K1), malnutrition control (K2), malnutrition with PFPC 13.26 mg.g-1 body weight (BW)/day (X1), malnutrition with PFPC 19.89 mg.g-1 BW/d (X2), and malnutrition with casein supplement 13.26 mg.g-1 BW/d (X3). K1 received a standard diet, while the others received a low 8% protein diet (L8PD) since those were born until 21 days. The standard diet was refed for all groups during the intervention (14 days). IGF-1 and IGFBP-3 levels were measured by ELISA. Normal data were analyzed by using One-way ANOVA which then was followed by post-hoc Bonferroni. Meanwhile, the others were analyzed by Kruskal Wallis and followed by Mann-Whitney U-test. Spearman test was used for correlation. PFPC contained 81.07% of protein, 4.08% of fat, 7.24% of moisture, 2.77% of ash, and 4.83% of carbohydrate. These contents had affected the growth factor. As a result, in the PFPC intervention, IGF-1, and IGFBP-3 levels (p <0.05) were decreased, while the controls were increased. The decreased values were shown in IGFBP-3 levels (p <0.05) while the increase was shown in both controls. On the other hand, the increase in body weight was shown in all groups, including control ones. A strong correlation was found between IGF-1 and IGFBP-3. PFPC has additional value on repairing malnutrition that is the best dose in effecting IGF-1 dan IGFBP3 levels is 13.26 mg.g-1 BW/d
Effects of selenium on macro- and micro nutrients and selected qualitative parameters of oat (Avena sativa L.)
Get PDFThe article deals with the effect of foliar Se application on macro-and micro-elements and selected quantitative parameters (the content of ash, starch, and fat) in oat grains. The three-year experiments were carried out on Research and Breeding Station Vígľaš – Pstruša in the years 2014, 2015, 2016. The used oat variety was Valentin. The experiment was performed by a block method within a parcel size of 10 square meters (8 x 1.25 m) with the span of rows amounting to 0.125 m in four replications. Alfalfa was grown as forecrop. A potato and wheat production area (III-C2) with a height of 375 m above the sea level. The experimental area is characterized by warm, slightly wet weather with an average annual temperature of 7.8 °C and average annual precipitations of 666 mm. Basic fertilizing was planned before the sowing in the form of 100 kg of Ammonium nitrate containing dolomite (27% N), 100 kg of 60% KCl (60% of K2O), and100 kg of MAP (Monoammonium phosphate 12% N and 52% P2O5). Selenium was foliar applied in doses 25 g and 50 g Se per hectare in a solution form of sodium selenate (Na2SeO4). The harvest was realized by a small plot harvester in BBCH 91. The results of the experiments showed a statistically non-significant effect on microelements and most macroelements. Only sulfur content in oat grains was statistically significantly influenced by Se foliar treatment. The contents of ash, starch, and fat in oat grains were monitored, which showed statistically significant effect only in fat. Se content in grains showed a statistically significant increase by both Se foliar treatments
Mathematical modeling of the oil extrusion process with pre-grinding of raw materials in a twin-screw extruder
Get PDFThe extrusion process of oil-containing raw materials using a twin-screw extruder is becoming increasingly common in food technology. The problem of high energy costs for the implementation of this process is solved by reducing the resistance of the process mass due to the preliminary grinding of raw materials. The classical theory of extrusion is based mainly on the use of theoretical solutions of mathematical models of processes, which are simplified and allow determining integral parameters using coefficients, the preparation of which for the calculation of the corresponding processes and equipment is a rather complicated and approximate procedure. Mathematical modelling of the movement of the technological medium at the individual stages of the processing of raw materials allows us to determine the analytical dependences for the power and energy parameters of the system and to carry out their effective technical and economic evaluation. Using the methods of mathematical analysis and data processing in the MathCAD software environment, graphical dependences of the power and energy parameters of the research technical system were obtained. By increasing the density of the oil-containing raw materials, which is extruded in the research extruder by 40.5% the pressure force increases by 41%, that is, there is an almost proportional relationship between the pressure force and the density of the processed raw material. With an increase in the angular velocity of the drive shaft ω more than 8 rad.s-1, the pressure force in the research process increases sharply. With an increase in the density of raw materials, it is grinded before extrusion by 40%, the power consumption for the grinding process increases by 2.8 times for the recommended operating mode. Energy losses for pressing completely grinded raw materials are reduced by 2.52 times
The The effect of fortified Dadih (fermented buffalo milk) with vitamin D3 on caecum cholesterol concentration and high sensitivity c-reactive protein (hs-CRP) level in type 2 diabetes mellitus rat model
No full textType 2 diabetes mellitus (T2DM) may be developed by a cardiovascular complication. T2DM and its complications associated with a decrease in levels of 25 hydroxyvitamin D below normal. The level of 25-OH-D can increase and it can be gained by probiotics supplementation. Dadih is a probiotic useful as antidiabetic, antiatherosclerotic, and it can reduce serum cholesterol. Vitamin D is beneficial for T2DM since it improves insulin production, acts as an anti-inflammatory and prevents dyslipidemia thereby preventing cardiovascular disease. This research aims to investigate the effects of giving dadih-fortified-vitamin-D3 toward caecum-cholesterol-concentration and hs-CRP-levels to T2DM-induced-rats. This study used a randomized pre-post test with control group design in 30 Wistar rats divided into 5 groups, namely T1, T2, and T3-treatment-groups. T3-group was given dadih-fortified-vitamin-D3, while T1 and T2-groups were given vitamin-D3 and dadih, respectively. The control groups were healthy-control (C1), and T2DM (C2). The intervention was given through oral sonde for 28days. The variables analyzed were caecal-cholesterol-concentrations using a spectrophotometer and hs-CRP using the ELISA method. The statistical tests were used for the caecum-cholesterol-concentration and hs-CRP levels. The mean of caecum-cholesterol-concentration in the T3-group (83.68 ±1.93mg.100g-1), was higher than T1 (77.99 ±1.70; p = 0.004) and C2-control (24.39 ±1.47; p = 0.0001). The mean of hs-CRP-level post-intervention in the T3-group (4.21 ±0.41 ng.mL-1), was lower than C2 (17.15 ±0.85;p = 0.0001), T1 (6.59 ±0.27; p = 0.0001) and T2 (5.43 ±0.39; p = 0.004). There is a very strong inverse correlation between the concentration of cholesterol and hs-CRP ( r = -0.979, p = 0.0001). The conclusion is dadih-fortified-vitamin-D3 –intervention is better than its single intervention as an anti-inflammation which might relate to the increased caecum-cholesterol-concentration.
Interaction of polyphenols extract from Polygonum multiflorum Thunb. roots with gelatin and toxicity of extract in mice
Get PDFThe roots of Polygonum multiflorum Thunb. (Vietnamese name: Ha-thu-o-do, HTOD) are used in processed form or the raw state in traditional Vietnamese medicine for many diseases and in extract form in the food industry. Some studies pointed out that HTOD extract had toxicity in humans. However, the toxicity of this herb plant currently remains unclear. In addition, this material contained a large amount of bioactive compounds, especially phenolic compounds. They have a strong antioxidant capacity and they can also interact with many different substrates such as protein, enzyme, lipid and carbohydrate. In this study, the received extracts from HTOD had the polyphenols concentrations of 415, 277, 208 and 166 (mg GAE.L-1), respectively. Besides, we only evaluated the gelatin-polyphenols interaction and the toxicity of HTOD extract in Swiss mice. The results show a strong gelatin-polyphenols interaction and no acute or subacute toxicity in mice. The polyphenols extract of HTOD at the concentration tested in this study is safe to use in food
The characteristic of sheep cheese “Bryndza” from different regions of Slovakia based on microbiological quality
Get PDFThe aim of our study was to describe microorganisms which occur in the traditional Slovak cheese „Bryndza“. There were a total of 60 cheese samples collected from ten different farms during May 2019. The microbiota studies included the total bacterial count, coliforms, enterococci, lactic acid bacteria, yeasts and microscopic fungi. The total bacterial counts were cultivated on plate count agar at 30 °C in aerobic conditions, lactic acid bacteria on MRS at 37 °C in anaerobic conditions, coliform on VRBL and VRBG at 37 °C in aerobic condition, yeasts and microscopic fungi on MEA at 25 °C under aerobic condition. Gram-positive, Gram-negative and yeasts isolates were identified with MALDI-TOF MS Biotyper. Totally, a number of 1175 isolates of G-, G+ and yeast were identified with score higher than 2 and moulds. Escherichia coli and Stenotrophomonas maltophilia were the most frequently identified species of Gram-negative and Leuconostoc mesenteroides ssp. mesenteroides and Lactococcus lactis ssp. lactis from Gram-positive bacteria. Yarrowia lipolitica and Kluyveromyces lactis were the most distributed yeasts. Lactic acid bacteria group was represented by Lactobacillus, Lactococcus, Leuconostoc and Pediococcus. The most abundant genera of lactic acid bacteria were Lactobacillus with 11 species. This study describes the indigenous microbiota of the traditional ewe's milk cheeses from Slovakia
Spontaneous fermentation in wine production as a controllable technology
Get PDFThis study focuses on the isolation of a consortium of microorganisms from spontaneously fermenting must that naturally contain lactic acid bacteria, non-saccharomyces yeasts, and saccharomyces yeasts. To collect the greatest diversity of microorganisms, the consortium was taken from the point of micro-sparkling. Based on the growth curves, isolation was performed using individual special nutrient media, and the isolates were subsequently multiplied in the nutrient medium. Individual isolates were then used for fermentation tests to monitor the percentage of fermented sugar and hydrogen sulphide production. The highest fermentation abilities were achieved in the isolates containing Saccharomyces cerevisiae and Zygosaccharomyces bailii. The smallest amount of ethanol was formed from the isolates containing Hanseniaspora uvarum, while Candida sake isolate produced the lowest amount of hydrogen sulphide and Zygosaccharomyces bailii produced the highest. The other isolates produced an average amount. Based on these results, a consortium containing the given isolates in a certain ratio was compiled