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Background/Aim. To our knowledge there are no data about the relationship between elevated risk for developing type 2 diabetes mellitus (DM2) and altered cardiac autonomic function. The aim of this study was to evaluate the association between heart rate variability (HRV) and slightly increased risk for DM2. Methods. We evaluated 69 subjects (50.0 ± 14.4 years; 30 male) without DM2, coronary artery disease and arrhythmias. The subjects were divided into two groups according to the Finnish Diabetes Risk Score (FINDRISC): group I (n = 39) included subjects with 12 > FINDRISC ≥ 7; group II (n = 30) subjects with FINDRISC < 7. HRV was derived from 24-h electrocardiogram. We used time domain variables and frequency domain analysis performed over the entire 24-h period, during the day (06-22 h) and overnight (22-06 h). Results. Standard deviation of the average normal RR intervals was significantly lower in the group with increased risk for DM2 compared to the group II (127.1 ± 26.6 ms vs 149.6 ± 57.6 ms; p = 0.035). Other time domain measures were similar in both groups. The group I demonstrated significantly reduced frequency domain measures, total power - TP (7.2 ± 0.3 ln/ms2 vs 7.3 ± 0.3 ln/ms2; p = 0.029), and low frequency - LF (5.9 ± 0.4 ln/ms2 vs 6.3 ± 0.6 ln/ms2; p = 0.006), over entire 24 h, as well as TP (7.1 ± 0.3 ln/ms2 vs 7.3 ± 0.3 ln/ms2; p = 0.004), very low frequency (6.2 ± 0.2 ln/ms2 vs 6.3 ± 0.2 ln/ms2; p = 0.030), LF (5.9 ± 0.4 ln/ms2 vs 6.2 ± 0.3 ln/ms2; p = 0.000) and high frequency (5.7 ± 0.4 ln/ms2 vs 5.9 ± 0.4 ln/ms2; p = 0.011) during the daytime compared to the group II. Nocturnal frequency domain analysis was similar between the groups. The low diurnal frequency was independently related to elevated risk for diabetes mellitus (beta = -0,331; p = 0.006). Conclusion. The obtained results suggest that even slightly elevated risk for developing diabetes mellitus may be related to impaired HRV.

Background/Aim. Many studies support the hypothesis that oxidative stress is involved in the pathogenic process of a variety of diseases including hypertension. In humans, hypertension is also considered a state of oxidative stress that can contribute to the development of arteriosclerosis and other hypertension- induced organ damage. The aim of this study was to evaluate an influence of acute physical exercise on antioxidative enzymes activity and lipid status in patients with hypertension. Methods. Forty patients with hypertension and 20 age-matched controls were included in the study. To assess an influence of acute exercise on lipids and antioxidative enzymes activity the following parameters were determined at rest and immediately after the acute cardiopulmonary exercise cycloergometer test: triglycerides (TG), total cholesterol, low density cholesterol (LDL), oxidised LDL cholesterol (OxLDL), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and plasminogen activator inhibitor (PAI). Results. In basal condition, hypertensive patients compared to the control group had increased, but not significantly, level of Ox LDL (88.61±14.06 vs 79.00±29.26 mmol/L), PAI (3.06±0.56 vs 2.6±0.35 U/mL) and activity of GSH-Px (50.22±15.20 vs 44.63±13.73 U/g Hb). After acute exercise test, there was significantly greater level of Ox LDL (79.0±29.26 vs 89.3±29.07 mmol/L; p < 0.05) only in the control group. GSH-Px activity was significantly decreased only in hypertensive patients after acute exercise (50.22±15.2 vs 42.82±13.42 U/g Hb; p < 0.05), but not in the controls. Conclusion. No significantly elevated Ox LDL, GSH-Px and PAI-1 levels were found in hypertensive patients during basal condition in comparison with healthy subjects. Decreased GSH-Px activity was associated with those in acute exercise only in hypertensive patients. It could be an important indicator of deficiency of physiological antioxidative defense mechanism in hypertensive patients during an acute exercise.

Background/Aim. Exercise is a well recognized model of oxidative stress and, also, an important tool in diabetes management. The aim of our study was to evaluate oxidative stress in patients with diabetes mellitus type 2 and to determine influence of acute exercise training on the investigated parameters. Methods. To evaluate oxidative stress in the patients, we determinated following parameters: triglycerides (TG), total cholesterol, low density lipoprotein cholesterol (LDL), oxidized LDL cholesterol (Ox LDL), superoxide dismutase (SOD), glutathione peroxidase (GSHPx), plasminogen activator inhibitor (PAI) which were measured at rest and immediately after the acute bout of cardiopulmonary exercise cycle-ergometer test. Results. In basal condition, diabetic patients compared to controls have significant higher values of TG (3.12 ± 1.09 vs 1.74 ± 0.9 mmol/L, p < 0.01), Ox LDL (84.73 ± 16.90 vs 79.00 ± 29.26 mmol/L, p < 0.05) and SOD enzyme activity (913.38 ± 120.36 vs 877.14 ± 153.18 U/g Hb, p < 0.05). During the acute exercise test, there was significant increase of Ox LDL in both the study patients (from 84.73 ± 16.90 to 92.33 ± 23.29 mmol/L, p < 0.05) and in the control group (from 79.00 ± 29.26 to 89.30 ± 29.07 mmol/L, p < 0.05). SOD activity was significantly increased in both groups during exercise, in diabetic patients from 913.38 ± 120.36 to 921.50 ± 130.03 U/gHb, p < 0.05, and in the controls from 877.14 ± 153.18 to 895.00 ± 193.49, U/gHb, p < 0.05. GSH-Px activity was significantly increased only in the diabetic patients after the acute exercise (from 45.04 ± 11.19 to 51.81 ± 15.07 U/gHb, p < 0.01), but not in the controls (from 44.63 ± 13.73 to 43.97 ± 25.97 U/gHb, p = ns). PAI significantly decreased during the exercise test, only in the healthy subjects (from 2.60 ± 0.35 to 2.22 ± 0.65, p < 0.05). Type 2 diabetic patients with complications had only significant increase in GSH-Px activity (from 47.10 ± 7.37 to 54.52 ± 11.97 U/gHb, p < 0.01). Conclusion. Elevated Ox LDL, SOD and GSH-Px levels are associated with acute exercise in type 2 diabetic patients. We suggest that it could be a compensatory mechanism to preventing free radicals tissue damage. We hypothesize that a physical training program induces an enhance of muscular and liver antioxidant enzymes activity and reduces oxidative stress. Further studies are needed to explore the relationship between exercise and antioxidant system in diabetic patients with and without complications.

Background/Aim. Exercise can positively influence risk factors associated with cardiovascular disease. The mechanisms by which exercise reduces atherogenic risk remain unknown. The aim of the present study was to investigate the effect of acute exercise (cardiopulmonary exercise cycle ergometer test) on atherogenic lipids in untreated mild hypertensive patients with or without hypercholesterolemia. This testing allows determination of exercise capacity, peak heart rate, and ventilation per minute (VE), peak oxygen uptake (pVO2) and exercise time (ET). Methods. The study group included 85 untreated mild hypertensive patients (according to VII Joint National Committee - JNC 7) divided into two subgroups: hypertensive hypercholesterolemic and hypertensive normocholesterolemic. The control group included 35 normotensive subjects divided into two subgroups: normotensive hypercholesterolemic and normotensive normocholesterolemic. Lipid profiles to determine were oxidized LDL (OxLDL) - a marker of oxidative stress, triglycerides, total cholesterol, LDL cholesterol, and HDL cholesterol, which were measured at rest and 30 minutes after the acute bout of cardiopulmonary exercise cycle ergometer test. Lipids profiles were measured by enzymatic methods. Oxidized LDL was determined by a commercially available sandwich ELISA (Mercodia AB, Uppsala, Sweden). C-reactive protein (CRP) was measured using chemiluminiscent methods (Immulite-DPC). Results. In our study OxLDL was significantly higher in hypertensive patients with atherogenic lipid profiles in basal condition, compared to the hypertensive patients without atherogenic lipid profiles and controls. There was a significant difference in CRP (p < 0.001) between hypercholesterolemics (hypertensive and normotensive) and normocholesterolemics (hypertensive and normotensive). We found increased OxLDL after exercise in both groups (hypertensive patients and normotensive), but only in the hypertensive hypercholesterolemic patients the difference was statistically significant (90.47 ± 15.31 vs. 105.94 ± 14.17 IU/L, p < 0.001). Systolic and diastolic blood pressures were significantly higher during exercise only in the hypertensive patients. There were significantly lower values of pVO2 only in hypertensive hypercholesterolemic patients. There were no significant differences between hypertensive and normotensive ones for ET and VE. In hypertensive ones we found after exercise a negative correlation between pVO2 and OxLDL (r = -0.473; p < 0.05), and pVO2 and CRP (r = -0.478; p < 0.05). We also found in normotensive normocholesterolemic patients a positive correlation between VE and systolic blood pressure (r = 0.420; p < 0.05), a negative correlation between VE and OxLDL (r = -0.421; p < 0.05), and VE and CRP (r = -0.561; p < 0.05). Conclusion. This study showed that acute exercise induces and increases oxidative stress only in untreated mild hypertensive patients with atherogenic lipid profiles. These results imply the need to normalize atherogenic lipid profile in untreated patients with mild hypertension in order to prevent an increased lipid peroxidation under acute exercise.

Background/Aim. It is well known that patients with coronary artery disease and viable tissue as a guarantee of contractile recovery (CR), despite of decreasing ejection fraction (EF) and systolic dysfunction, could have benefit from surgical revascularization. Therefore, relationship between diastolic filling type and early postoperative recovery and complications need to be established. The aim of this study was to investigate the relation between different left ventricular (LV) diastolic filling types and CR in patients after surgical revascularization with differently preserved systolic function. Methods. We investigated 60 patients. All of them had CR estimated by stress echocardiography regardless the extent of recovery of the heart systolic function. Echocardiographic evidence of diastolic dysfunction was estimated by Doppler examination of transmitral diastolic flow. According to the derived different diastolic filling types the patients were divided into three groups: I − patients with disorder of LV relaxation, II − with pseudovascularisation, and III − with restrictive filling type, and according to the value of systolic function into two subgroups: 1) relatively recovered systolic function − EF > 40% and 2) pronounced LV dysfunction − EF < 40%. Echocardiographic evaluation was performed before and two week after surgical revascularization. In the preoperative period the medication therapy was optimized. We estimated CR by echocardiografic paremeters but also by detection of cardiovascular events. Results. After CABG the mean value of WMSI LV tended to decrease in any groups: in the group I (n = 12) from 1.64±0.22 to 1.34±0.22; in the group II (n = 22) from 1.85±0.16 to 1.53±0.42, and in the group III (n = 26) from 1.92±0.29 to 1.81±0.52. The lowest improvement of systolic function according to EF value expressed by the number of patients was found in the group of patients with restrictive LV filling type (12; 53.8%) as contrasting to the group with pseudonormalisation (15; 78.9%). In the group of patients with restrictive diastolic filling type also was recorded the highest number of lethal outcomes (6; 23.1%), as well as cardiovascular complications (10; 38.5%). Conclusions. Restrictive LV diastolic filling type was the marker of poor prognosis in the patients with clinical heart failure undergoing surgical revascularization. The patients with heart failure and preserved systolic function were associated with similar prognosis.

Aim. To determine the prognostic significance of late ventricular potentials on signal-averaged electrocardiogram and left ventricular ejection fraction for the occurrence of complex ventricular arrhythmia in patients treated with accelerated tissue-type plasminogen activator, using the rapid protocol, within six months of acute myocardial infarction. Methods. In this analytic observational prospective study patients were divided into four groups: patients with left ventricular ejection fraction bellow 40% and late ventricular potentials, patients with left ventricular ejection fraction bellow 40% and without late ventricular potentials, patients with left ventricular ejection fraction over 40% and late ventricular potentials, and patients with left ventricular ejection fraction over 40% and without late ventricular potentials. Complex ventricular arrhythmias (Lown grade IVa, IVb, and V) were recorded using standard electrocardiography and 24-hour Holter monitoring 21, 60, and 90 days after acute myocardial infarction, respectively. Serial recordings of signal-averaged electrocardiogram were obtained 30, 90, and 180 days after acute myocardial infarction. Left ventricular ejection fraction was determined by echocardiography between 15 and 21 days after acute myocardial infarction. Multivariant logistic regression analysis was used to evaluate the relation between late ventricular potentials and left ventricular ejection fraction with the occurrence of complex ventricular arrhythmias. Sensitivity, specificity, positive and negative predictive values of late ventricular potentials and left ventricular ejection fraction for the occurrence of complex ventricular arrhythmias were determined. Results. The prospective study included 80 patients (73% men), mean age 64 ± 3.5 years. Complex ventricular arrhythmias were recorded in 34 (42.5%) of patients, all 17 (50%) of which were from the first group (p

The effect of different UV-C irradiation doses on tubers and sliced potato (with or without sample's turning during irradiation) on aerobic mesophilic bacteria count (AMB), phenolic composition and visual appearance of potatoes after 24 h storage at 10 °C was examined. Doses of UV-C irradiation were 1.08, 2.70, 5.40 and 10.08 kJ m-2 for tubers and 1.08, 1.62 and 2.70 kJ m-2 for potato slices. UV-C irradiation, particularly with slice turning, caused the significant reduction of the AMB in comparison with untreated potatoes in accordance to the irradiation dose. Further, it caused a significant increase of phenolic substances in all samples, especially in tubers, although inversely to the irradiation dose. Independently of the applied treatment, chlorogenic acid, caffeic acid and rutin were identified in all samples where chlorogenic acid was predominant. Generally, the turning of potatoes during irradiation had a significant effect on the increase of chlorogenic acid in potato slices. Samples with higher phenolic content were more prone to browning. Based on all obtained results UV-C treatment of potato slices with dose 1.62 - 2.70 kJ m-2 and with turning could be recommended as the most promising treatment. [ABSTRACT FROM AUTHOR]

Research Background: Potato tissue is damaged during fresh-cut production, which makes fresh-cut potato susceptible to the quality loss and microbiological spoilage. At the same time, such products are desirable due to their convenience; however, they are extremely sensitive and have short shelf life. The main challenge of the fresh-cut potato industry is to find possibilities to overcome these drawbacks. UV-C treatment, known for its antibacterial activity, is a promising technique and it shows a potential to improve shelf life of fresh-cut potato products., Experimental Approach: The influence of the UV-C treatment on the safety and quality, as well as sensory traits of fresh-cut potato ( Solanum tuberosum L. cv. Birgit) during storage was examined. For this purpose, 0-, 3-, 5- and 10-min UV-C irradiation was applied on vacuum-packed potato slices pretreated with sodium ascorbate solution. During 23 days of storage at (6±1) °C, microbiological, physicochemical and sensory properties of raw samples were monitored, along with sensory properties of boiled and fried fresh-cut potatoes., Results and Conclusions: The 5- and 10-min UV-C treatments significantly reduced microbial growth, increased total solids and lightness ( L* ), and positively affected odour and firmness of raw potatoes. Cooked UV-C-treated samples were described with more pronounced characteristic potato odour and taste. Overall, UV-C-treated fresh-cut potato retained its good quality and sensory traits up to 15 days at (6±1) °C., Novelty and Scientific Contribution: To the best of our knowledge, this is the first scientific article dealing with the effect of UV-C light on durability (safety, quality and sensory traits) of fresh-cut potato cv. Birgit and its suitability for boiling and frying. In general, UV-C treatment is a known antimicrobial technique, but its application on fresh-cut potato is poorly explored. Results confirmed that vacuum-packed fresh-cut potato treated only with UV-C and sodium ascorbate as anti-browning agent, without the addition of chemical preservatives, had twofold longer shelf-life at (6±1) °C than the fresh-cut potato not treated with UV-C. Fresh-cut potato treated with UV-C retained good overall quality and sensory properties either raw, boiled or fried. Results of this study could also be useful for producers in terms of potential UV-C application as a strategy for prolonging the shelf-life of fresh-cut potato., Competing Interests: CONFLICT OF INTEREST Authors declare no conflict of interest.

Marine microalgae and cyanobacteria are sources of diverse bioactive compounds with potential biotechnological applications in food, feed, nutraceutical, pharmaceutical, cosmetic and biofuel industries. In this study, five microalgae, Nitzschia sp. S5, Nanofrustulum shiloi D1, Picochlorum sp. D3, Tetraselmis sp. Z3 and Tetraselmis sp. C6, and the cyanobacterium Euhalothece sp. C1 were isolated from the Adriatic Sea and characterized regarding their growth kinetics, biomass composition and specific products content (fatty acids, pigments, antioxidants, neutral and polar lipids). The strain Picochlorum sp. D3, showing the highest specific growth rate (0.009 h -1 ), had biomass productivity of 33.98 ± 0.02 mg L -1 day -1 . Proteins were the most abundant macromolecule in the biomass (32.83-57.94%, g g -1 ). Nanofrustulum shiloi D1 contained significant amounts of neutral lipids (68.36%), while the biomass of Picochlorum sp. D3, Tetraselmis sp. Z3, Tetraselmis sp. C6 and Euhalothece sp. C1 was rich in glycolipids and phospholipids (75%). The lipids of all studied microalgae predominantly contained unsaturated fatty acids. Carotenoids were the most abundant pigments with the highest content of lutein and neoxanthin in representatives of Chlorophyta and fucoxanthin in strains belonging to the Bacillariophyta. All microalgal extracts showed antioxidant activity and antimicrobial activity against Gram-negative E. coli and S. typhimurium and Gram-positive S. aureus .

UV-C irradiation successfully reduces the growth of microorganisms, but it can also affect the content of phenolics and sugars of fresh-cut potatoes (FCP). This could consequently alter antioxidant capacity of FCP or its potential for acrylamide formation. Therefore, this paper investigates the influence of UV-C irradiation on the content of phenolics [chlorogenic acid (CA)] and individual sugars during storage of FCP as well as after cooking. Acrylamide was also monitored in FCP after frying. Potato slices pre-treated with sodium ascorbate solution and vacuum-packaged were UV-C irradiated for 0, 3, 5, and 10 min in order to obtain irradiation doses of 0, 1.62, 2.70, and 5.40 kJ m -2 , respectively, stored for 23 days (+6 °C), and subsequently boiled and fried. As the applied dose and storage duration increased, the CA content in raw FCP decreased (it retained for 75.53-88.34%), while the content of sugars as well as acrylamide in fried FCP increased. Although the increase was the most noticeable at the applied dose of 2.70 kJ m -2 , the acrylamide content was always below proposed limit. Boiling and frying reduced the content of CA and sugars. In spite of certain alterations, applied doses of irradiation can ensure acceptable product in regard to phenolics and sugars, and acrylamide content particularly.

Certain changes in phenolics and sugars can occur during the storage of potatoes, where particularly amounts of sugars represent the critical factor as they are involved in potentially harmful acrylamide (AA) formation during frying. This research investigates the impact of cultivars (Birgit and Lady Claire), tuber's age (1, 5, and 9 months), and storage duration (1, 5, and 8 days at 10 °C) on the content of phenolics and sugars in raw, boiled, and fried fresh-cut potato (FCP). The influence of these factors on the formation of AA in fried FCP was also assessed. Significant differences in phenolics and sugars were observed between cultivars (cv. Birgit contained 5.77 mg of phenolics 100 g -1 of dry weight (DW) and 1.75 g of sugars 100 g -1 DW, while cv. Lady Claire contained 10.13 mg of phenolics 100 g -1 DW and 0.65 g of sugars 100 g -1 DW). The content of phenolics significantly decreased, while sugars increased during tubers' aging. FCP storage time had no significant influence on the content of phenolics and sugars. The phenolics and sugars were the highest in the raw samples and the lowest in the boiled ones. Although the AA level in fried samples was significantly influenced by cultivar (Birgit > Lady Claire) and it increased with FCP storage time, it was below European Food Safety Authority (EFSA) regulation's approved maximum value (750 µg kg -1 FW) in both cultivars. Therefore, cvs. Birgit and Lady Claire could be considered as promising FCP cultivars and for frying purposes. PRACTICAL APPLICATION: The results of this research reveal that quantitative changes of chemical constituents occurring during storage and cooking of fresh-cut slices of potato cultivars Birgit and Lady Claire are not a concern. This is of particular importance to fresh-cut producers and customers. Phenolics were reduced during storage, but they were still present in all cooked samples independently of the cooking method. The analysis of sugars showed that tubers as old as 9 months could be used for fresh-cut potato processing, providing safe frying without critical levels of acrylamide., (© 2021 Institute of Food Technologists®.)

Research Background: Mastic tree ( Pistacia lentiscus L.) of the Anacardiaceae family is an evergreen shrub from Mediterranean countries where it is used in traditional medicine. Analysis of P. lentiscus leaf, stem, fruit and root extracts showed high concentrations of principal groups of secondary metabolites (flavonoids, phenolic acids and tannins), suggesting the plant possesses great biological potential. Therefore, the aim of this research is to evaluate the impact of environmental parameters and the extraction solvent type on the concentration of phenols in mastic tree leaf extracts grown at four different locations along the Adriatic coast (Barbariga, Lun, Hvar and Vela Luka) during three phenological stages (early flowering, early fruiting and late fruiting)., Experimental Approach: Since mastic tree plant has phenolic compounds with different structures and chemical properties, ethanolic and methanolic leaf extracts were analysed using high-performance liquid chromatography (HPLC) coupled with UV/Vis PDA detector. Phenolic compounds were identified by comparing the retention times and spectral data with those of standards at 280 and 340 nm., Results and Conclusions: In all samples, phenolic acids and flavonol glycosides were quantified, while catechin was quantified only in methanolic extracts. The 5- O -galloylquinic acid was determined as a predominant phenolic compound in all samples followed by monogalloyl glucose, 3,5-di- O -galloylquinic acid, 3,4,5-tri- O -galloylquinic acid and gallic acid, respectively. Myricetin-3- O -rhamnoside was found to be the predominant flavonol glycoside followed by myricetin-3- O -glucoside, myricetin-3- O -glucuronide, quercetin-3- O -rhamnoside and derivative of flavonol glycoside. The mass concentration of these compounds significantly varied during different phenological stages, at different growing locations and used extraction solvents. The highest phenolic mass concentration was determined in the samples harvested at Hvar growing location and extracted in 80% methanol. The highest total phenolic acid mass concentration was obtained in the samples harvested during the flowering phenological stage and the highest total flavonoid mass concentration in the samples harvested during the early fruiting stage., Novelty and Scientific Contribution: The obtained data provide a better understanding of the P. lentiscus species phenolic concentration, which can lead to further investigations regarding the valorisation of mastic tree leaves as pharmaceutical products or as food products with added value., Competing Interests: CONFLICT OF INTEREST All authors declare that they have no conflict of interest

The objective of this study is to investigate the influence of cultivar and industrial processing on total polyphenols, anthocyanins, hydroxycinnamic acids and antioxidant activity in concentrated sour cherry ( Prunus cerasus L ., cvs. Marasca and Oblačinska) juices. Samples were collected during four processing steps: from fresh fruit prior to processing, then from pressed, filtered and concentrated juices. The content of total phenols was the same in both cultivars, but antioxidant activity (Oblačinska>Marasca) and total monomeric anthocyanins (Marasca>Oblačinska) differed. All processing steps significantly influenced the content of total phenols, total monomeric anthocyanins and antioxidant activity. In all samples four major anthocyanins were identified by HPLC with UV/VIS PDA detector, listed in the descending order based on their abundance: cyanidin-3-glucosylrutinoside, cyanidin-3-rutinoside, cyanidin-3-sophoroside and cyanidin-3-glucoside. Marasca cv. contained more total anthocyanins, and contents of cyanidin-3-sophoroside and cyanidin-3- -glucosylrutinoside. The content of total hydroxycinnamic acids was also higher in Marasca than Oblačinska cv. After processing, the concentration of all identified anthocyanins increased in both cultivars. Majority of the highest values of polyphenols were detected in the juice after pressing. The content of polyphenols and their antioxidant activity were considerably stable during industrial processing to concentrated juice. Although Marasca had higher polyphenolic content than Oblačinska, both cultivars showed promising industrial potential for processing to concentrated juice.