Investigation of effect of total dietary fibre and resistant starch on reduction of risk factors for diabetes mellitus type 2 in obese patients with disordered glucoregulation

Pravilan način ishrane je važan preduslov za zdrav i kvalitetan način života. U promociji zdravog i kvalitetnog načina ishrane u današnje vreme dijetna vlakna zauzimaju značajno mesto. Obzirom da vlakna predstavljaju veliki broj jedinjenja različitih molekulskih masa, fizičkih osobina i fizioloških efekata, u literaturi se koristi više klasifikacija. Na osnovu vrste monosaharidnih jedinica koje ulaze u sastav polimera i načina vezivanja, dijetna vlakna se mogu podeliti na različite frakcije. Te frakcije su: rezistentan skrob, beta-glukan, arabinoksilan, celuloza, fruktan. Osim što se razlikuju po hemijskoj strukturi, različite frakcije imaju i različite fiziološke efekte, što je povrđeno u brojnim istraživanjima. Podaci govore da osobe sa visokim unosom vlakana (>25 g/dnevno) mogu da smanje progresiju predijabetesa u dijabetes. Unosom hrane bogate rezistentnim skrobom, jedne od frakcija vlakana, povećava se period sitosti i smanjuje postprandijalna glikemija. Količina od 15-30 g dnevno rezistentnog skroba datog kao dodatak uz redovnu ishranu povećava insulinsku senzitivnost. Na osnovu do sada proučenih efekata vlakana postavljeni su ciljevi ove doktorske disertacije: (I) da se odredi sadržaj ukupnih dijetnih vlakana, kao i frakcija dijetnih vlakana rezistentnog skroba, arabinoksilana, celuloze, fruktana i beta-glukana u uobičajenim izvorima u voću i povrću, u komercijalnim hlebovima, u pahuljicama od žitarica, kao i u termički obrađenim namirnicama kao što su žita i leguminoze; (II) da se procene efekti i razlike u delovanju ukupnih dijetnih vlakana i ukupnih dijetnih vlakana sa definisanom količinom rezistentnog skroba, iz različitih dijetarnih izvora na glikemiju, insulinemiju, i lipemiju kod gojaznih pacijenata sa poremećenom glikoregulacijom. Dobijeni rezultati o količini ukupnih dijetnih vlakana i rezistentnog skroba u namirnicama našeg podneblja korišćeni su pri izboru dijetarnih izvora koji su preporučeni ispitanicima koji su učestvovali u dijetarnoj intervenciji. U istraživanju...Proper dieting is inevitable part of healthy way of life. Dietary fibres are one of the nutrients that are highly positioned in promotion of healthy nutrition. Since dietary fibres consist of numerous compounds with different molecular mass, physical properties and physiological effects, in literature it is common to find them classified by more than one criterion. Thus, based on the type of the monosaccharide unit and linkage in particular polymer, dietary fibres are divided into the fractions: resistant starch, betaglucan, arabinoxylan, cellulose and fructan. Besides differing in chemical structure, dietary fibre fractions are also specific in terms of physiological action in the body, which has been largely proven in multitude of scientific investigations. Literature data indicate that subjects with high dietary fibre intake (>25 g/daily) are capable of slowing down a progression of prediabetic condition into diabetes. Eating foods that are rich in resistant starch can help in achieving prolonged period of satiety, thus decreasing a postprandial glycemia. Furthermore, the improvement of the insulin sensitivity was achieved with 15-30 g of resistant starch taken daily in the form of dietary supplement. Mentioned above are the premises taken into account when setting the goals of the actual PhD thesis: A) to determine both the content of total fibre and its fractions (resistant starch, arabinoxylan, cellulose, fructan and beta-glucan) in foods known to be their common sources, such as: fruits and vegetables, industrial bakery, grain flakes and products from heat processed grains and legumes; B) to estimate the effectiveness of increased intake of total dietary fibre versus total fibre with predefined amount of resistant starch derived from various food sources on glycemia, insulinemia and lipemia in obese patients with impaired glucoregulation. Obtained results regarding total dietary fibre and resistant starch content in common foods were used in forming precise dieting recommendations to the participants of this dietary intervention..

Fibre and polyphenols of selected fruits, nuts and green leafy vegetables used in Serbian diet

Fruits and vegetables are known as good sources of numerous bioactive compounds among which polyphenols and dietary fibre are considered essential because of their protective health effects. The aim of this study was to characterize the quality of selected plant foods of Serbia regarding the amount of total phenols, fibres and ratio of certain fractions of fibre. Fifteen samples of plant foods (green leafy vegetables, fruits and nuts) were evaluated for their total antioxidant activity, total phenolic content, total, soluble and insoluble fibre and fractions of fibre: beta-glucans, arabinoxylan, cellulose and resistant starch. Generally, nuts were the richest sources of fibre and total phenols. However, when serving size was taken into consideration, it appeared that raspberry and blackberry were the richest in total, soluble fibre and cellulose. Furthermore, almonds and hazelnuts were particularly rich in insoluble fibre, while walnuts had the highest polyphenol content. The analyzed plant foods were poor sources of arabinoxylan and beta-glucan. Data on the presence of resistant starch in cashew nut was the first confirmation that resistant starch could be found in significant amount in some nuts. The results give rare insight into the quality of selected plant foods regarding dietary fibre and polyphenols from the nutritive point of view

Chemical characterization, antioxidant and antimicrobial properties of goji berries cultivated in serbia

Since the fruits of Lycium L. species (Fructus lycii, goji berries) are promoted as a “superfood” with plenty of health benefits, there is extensive research interest in their nutritional and phytochemical composition. In the present study, the nutritional value, minerals, fatty acid composition, and bioactive compounds of L. barbarum L., red, yellow, and black goji berry (L. ruthenicum Murray.) cultivated in Serbia were investigated. Antioxidant and antimicrobial properties of their methanol extracts were assessed. Red goji berry had the highest content of fats, dietary fiber, iron, total carotenoids, and 2-O- -d-glucopyranosyl-l-ascorbic acid (AA-2 G). The yellow goji berry extract showed the highest level of flavonoids and the most prominent antimicrobial (especially against Gram-negative bacteria) properties. The highest total phenolic content and the most potent antioxidant activity were observed for the extract of black goji berry. Therefore, all goji berries could be a valuable source of bioactive compounds in the food and pharmaceutical industry

Suplementacija magnezijuma i status gvožđa kod studentkinja - studija intervencije

Abstract Background: Literature data indicate the benefit of magnesium (Mg) supplementation. The aim of this study was to examine the effect of short-term Mg supplementation on iron status in healthy female participants. Methods: One hundred healthy female students of the University of Belgrade - Faculty of Pharmacy participated the study during eleven intervention days. Students ingested Mg preparations with the same dose of the active substance. The analysis included the measurement of serum iron, unsaturated iron binding capacity (UIBC), total iron binding capacity (TIBC), total Mg (tMg), ionized Mg (iMg), complete blood count, met-, carboxy- and oxy-haemoglobin (metHgb, COHgb, O2Hgb). Transferrin concentrations and percentage of transferrin saturation (SAT) were calculated manually. The association among the analyzed biochemical parameters was examined using polynomial regression. A principal component analysis (PCA) was used for the evaluation of interdependence between the analyzed parameters. Results: A statistically significant trend for change in O2Hgb (%) by tertiles of iMg concentrations was found (P = 0.029). Serum tMg reached significant positive correlation with the SAT at concentration levels greater than 0.9 mmol/L, after 11 days of intervention (R2=0.116). Ionized Mg in a concentration higher than 0.6 mmol/L is positively correlated with SAT and serum Fe (R2=0.214; 0.199, respectively). PCA revealed variability of 64.7% for two axes after 11 days. Conclusions: Mg supplementation leads to an improvement in the certain iron status parameters even in individuals with optimal levels of these indices. However, caution should be exercised when supplementing Mg, and laboratory monitoring of the interaction is required.Uvod: Literaturni podaci ukazuju na benefit suplementacije magnezijumom (Mg). Cilj ove studije bio je da se ispita uticaj kratkotrajne suplementacije Mg na status gvožđa kod zdravih žena. Metode: Sto zdravih studentkinja Univerzitet u Beogradu - Farmaceutskog fakulteta je učestvovalo u istraživanju tokom jedanaest dana intervencije. Studenti su uzimali preparate Mg sa istom dozom aktivne supstance. U serumu je određivano gvožđe, nezasićen kapacitet vezivanja gvožđa (UIBC), ukupan kapacitet vezivanja gvožđa (TIBC), ukupan Mg (tMg), jonizovni Mg (iMg), kompletna krvna slika, met-, karboksiioksihemoglobin (metHgb, COHgb, O2Hgb). Transferin i saturacija transferina (SAT) su izračunati ručno. Povezanost analiziranih biohemijskih parametara je ispitana pomoću polinomalne regresije. Za procenu međuzavisnosti između analiziranih parametara korišćena je analiza glavnih komponenti (PCA). Rezultati: Utvrđen je statistički značajan trend promene O2Hgb (%) po tertilima koncentracija iMg (P = 0,029). Ukupan Mg je dostigao značajnu pozitivnu korelaciju sa SAT pri koncentracijama većim od 0,9 mmol/L, nakon 11 dana intervencije (R2 = 0,116). Jonizovani Mg u koncentraciji većoj od 0,6 mmol/L pozitivno korelira sa SAT i gvožđem (R2 = 0,214; 0,199, redom). PCA analizom je pokazana varijabilnost od 64,7% za dve ose nakon 11 dana. Zaključak: Suplementacija Mg dovodi do poboljšanja određenih parametara statusa gvožđa čak i kod pojedinaca sa optimalnim nivoima ovih parametara. Međutim treba biti oprezan pri suplementaciji Mg, a dodatno je neophodno i laboratorijsko praćenje ovih interakcija

Phenolics and Flavonoid Content in Selected Seeds from the Serbian Market

Objectives: Edible seeds are usually consumed as common food ingredients. They are considered to have a rich nutrient profile, containing different macro and micronutrients, as well as some biologically active compounds with positive health effects, such as different phenolics. The aim of this work was to determine total phenolics (TPC) and total flavonoid content (TFC) in selected commercial seeds samples from the Serbian market. Methods: Samples of nine seeds were investigated (sesame and black sesame, raw and roasted sunflower, raw and roasted pumpkin, hemp, chia and linseed). The samples of native seeds and those defatted using dichloromethane (maceration and Soxhlet extraction) were extracted with 80% methanol. Obtained hydro-methanol extracts were dried and further analysed using spectrophotometric methods: TPC was determined using Folin–Ciocalteu (FC) reagent and expressed as gallic acid equivalents (GAE), while TFC was measured based on the reaction between flavonoids and aluminium chloride and expressed as catechin equivalents (KE). Results: In general, hydro-methanol extracts of seed samples defatted using Soxhlet extraction had the highest TPC and TFC contents. TPC values ranged from 9.47 g GAE/mg (raw pumpkin seed) to over 170 g GAE/mg (raw sunflower seeds). As for TFC, the highest amount was measured in extracts of defatted raw sunflower seeds (over 150 g KE/mg), while roasted pumpkin and hemp seeds’ extracts were practically devoid of flavonoids. Conclusion: Our results confirmed the fact that certain defatted seeds, which are usually considered as waste products in oil production, could be considered as valuable sources of certain secondary plant metabolites, implicating further investigations on their composition and potential in the development of functional foods.Presented at the 14th European Nutrition Conference FENS 2023, Belgrade, Serbia, 14–17 November 2023

Similarities and differences in the nutritional composition of nuts and seeds in Serbia

Nuts and seeds are an indispensable part of the plant-based diet, which is becoming increasingly popular due to the evidence of their health benefits and contribution to sustainability and planetary health. Since the health effects of consuming nuts and seeds directly depend on their nutritional composition and consumed amount, it is essential to know the exact chemical composition of each nut and seed so that appropriate dietary interventions can be adequately planned. The present study aimed to examine the chemical composition of nuts and seeds obtained from the Serbian market and to highlight the similarities and differences in their nutritional composition. In twenty-four samples of nuts and seeds, the content of total lipids, including fatty acid profile, total proteins, including amino acid profile, total carbohydrates (sugars and fibers), phytosterols, and minerals were determined. Content of selected nutrients in grams (g) or milligrams (mg) of nuts and seeds was expressed in one portion (28 g) and as a percentage of contribution of Reference Intakes (% RI) and Dietary Reference Value (% DRV) for macronutrients and minerals, respectively. Some of the seed representatives appeared to be rich sources of essential omega-3 fatty acid, α-linolenic acid (ALA) (flax seed vs. walnut, 6.50 vs. 0.56 g per portion, respectively), dietary fibers (chia seed vs. raw almond, 10.6 vs. 3.4 g per portion, respectively), calcium (black sesame seed vs. almond roasted, 32.4% NRV vs. 8.1% NRV per portion, respectively), magnesium (hemp seed vs. Brazil nut, 38.3% NRV vs. 27.8% NRV per portion, respectively), and zinc (hemp seed vs. pine nut, 21.4% NRV vs. 17.6% NRV per portion, respectively). Our results highlighted the crucial role of seeds in the diet, especially as a better source of nutrients compared to nuts. Furthermore, it was seen that nuts and seeds are different and complementary in their composition. Thus, in order to meet the needs for certain nutrients for which nuts and seeds are used as dietary sources (essential fatty acids, minerals, dietary fibers), it would be beneficial to combine both nuts and seeds as a part of a healthy dietary pattern

Quality characteristics of oils from selected edible seeds

Many types of vegetable oils produce around the world. They are useful in nutrition, prevention and treatment of diseases. Some oils traditionally have been well known for a long time and have been shown many potential health benefits, such as, cardioprotective effect, effect on digestion, risk of some cancer and it is also used in the treatment of skin infections. This work was conducted to study some quality criteria of oil extracted from seven different raw seeds purchased in the Serbian market, namely: sunflowers, sesame seeds, black sesame seeds, tickles seeds, chia seeds, flax seeds and hemp seeds. Oils are essentially regarded in terms of quality based on their free fatty acid, iodine value and peroxides value. Oils were extracted from the seeds by cold extraction with petroleum ether. Quality characteristics, such as refractive index, acid value, peroxide value, iodine value and saponification value and unsaponifiable matter were determined. For the determination of these parameters, official methods (ISO 6320; ISO660; ISO 3960; ISO 3961; ISO 3657 and ISO 18609, respectively) were used. The contents of investigated parameters in seed samples were determined in the range of 1.467 to 1.485 nD for refractive index; 1.62 to 4.95 mg KOH/g for acid value; 5.21 to 7.45 for peroxide value; 118 to 197 for iodine value; 180 to 193 for saponification value and 3.14 to 7.26 g/kg for the unsaponifiable matter. Data obtained in this investigation indicate that all quality parameters of the seed samples, except peroxide value , comply with the national and Codex standards.10th International Congress of Food Technologists, Biotechnologists and Nutritionists, 30.11-2.12.2022. Zagreb, Croati

Amino acids composition in selected nuts

In recent years, we are witnessed that a nuts very popular food and is recommended as part of a diet because it contains numerous bioactive compounds. Nuts contain a high quantity of protein, i.e. amino acids that are known to be necessary for important processes such as tissue growth, energy production, immune function and nutrient absorption. In order to check the amount of individual amino acids found in the favorite samples of nuts of our citizens, we determined total protein and amino acid profile (17 amino acids) in nine samples of nuts (peanut, almond, hazelnut, walnut, Brazil nut, cashew, pecan, pistachio, and pine nuts). Total amino acids composition was determined by ion chromatograph with electrochemical detector, manufactured by Thermo, model ICS-5000, with silver reference electrode (Ag / AgCl) and gold (Au) working electrode and chromatographic column AminoPac PA10 and pre-column AminoPac PA10 guard. Analyzed nuts samples contained 11.7-29.2 g/100 g total proteins. Pecan contained the least protein, while peanut was the richest in total protein. Among the amino acids, glutamic acid, aspartic acid and arginine contents were generally high, whereas methionine, cysteine, histidine and tyrosine contents were low. Peanut was the most important source for essential amino acids (lysine 1.08 g/100 g; histidine 0.71 g/100 g; threonine 0.87 g/100 g; leucine 1.97 g/100 g; isoleucine 1.25 g/100 g; valine 1.07 g/100 g; phenylalanine 1,38 g/100 g; and methionine 0.4 g/100 g). Cashew was the biggest source of essential amino acids, 37% (essential/total amino acids), while the smallest source was almond, 27%. Almond was the biggest source of non-essential amino acids, 73%. The obtained results indicate that the nuts are incomplete in the content of amino acids. Knowledge of the amino acid composition of nuts is essential for combination with other food groups when formulating a balanced diet.UNIFood2021 Conference, 24th-25th September 2021 University of Belgrade, 2nd International UNIfood Conferenc

Dietary Intakes of Sugar in the Student Population from Fruits and Beverages

Objectives: A healthy diet includes the intake of sugar (up to 5%) from natural sources, because added sugars increase energy but not nutritional value, and are associated with an increased risk of developing obesity, cardiovascular diseases and hypertension. Sugars present in fresh fruit, fruit juices and nectars, refreshing soft drinks and alcoholic drinks usually represent half of the total sugar intake. The aim of this study was to analyze, through surveys, the habits of the student population regarding the consumption of food from the sources mentioned and to determine the amount of sugar consumed. Methods: 123 students (male: 36, female: 87), aged 19 to 32, participated in this research. Data collection was voluntary and anonymous, and the survey was conducted using an electronic questionnaire during February 2023. The data on the sugar content of the foods mentioned were taken from the declarations of the products that are available for free sale. Results: Based on the processed results from the completed questionnaires, it was concluded that from the sources mentioned, sugar is represented by 3.7% in relation to the total energy intake, and added sugar by 2.4% if 2000 kcal/day is consumed. In relation to the representation of carbohydrates of 60% in relation to the total energy intake, the sugar content from the tested sources accounted for 6.3%, and added sugar accounted for 4.0%. Students reported that they most often do not consume hard liquor (88% of respondents), and that they eat a teaspoon of honey/sugar once a day (14% of respondents). Conclusion: Although the obtained results are very acceptable and encouraging, it is necessary to act additionally in terms of increasing awareness of the reduced intake of products with added sugars and their replacement with those that contain biologically active compounds in addition to natural sugar composition.Presented at the 14th European Nutrition Conference FENS 2023, Belgrade, Serbia, 14–17 November 2023

Black Trumpet, Craterellus cornucopioides (L.) Pers.: Culinary Mushroom with Angiotensin Converting Enzyme Inhibitory and Cytotoxic Activity

Nutritional value and chemical composition, including the content of vitamins, fatty acids, 5'-nucleotides and nucleosides and amino acids, as well as biological activities, including antioxidant, angiotensin converting enzyme (ACE) inhibitory and cytotoxic activity of black trumpet (Craterellus cornucopioides (L.) Pers.) were tested in vitro. C. cornucopioides was low in energy, fat and carbohydrate contents, but rich in dietary fibre, especially β-glucan as well as niacin and α-tocopherol. The content of essential and non-essential free amino acids was 1.49 and 5.48 mg/g dry weight (dw). The nucleosides and 5'-nucleotides were determined at 1.84 and 3.99 mg/g dw, respectively. The share of unsaturated fatty acids (UFAs) was 75.92% with oleic acid as the major UFA. Cyclohexane and dichloromethane extracts expressed significant cytotoxic activity against selected cell lines, human epithelial cervical cancer cells (HeLa), adenocarcinomic human alveolar basal epithelial cells (A549), colorectal cancer cells (LS174) and normal MRC-5 human embryonic lung fibroblast cells (IC50 of 78.3-155.6 μg/mL). ACE inhibitory activity of the aqueous extract was strong with an IC50 of 0.74 μg/mL. It can be concluded that black trumpet is a good source of nutrients, such as vitamins, dietary fibres, amino acids, nucleotides and fatty acids, which contribute to the overall nutritional value of this fungus with potential for ACE inhibitory activity and use in anti-hypertensive diet