Inhibitory effects of bioaccessible anthocyanins and procyanidins from apple, red grape, cinnamon on α-amylase, α-glucosidase and lipase.

The goals of this study were to determine and evaluate the bioaccessibility of total anthocyanin and procyanidin in apple (Amasya, Malus communis), red grape (Papazkarasi, Vitis vinifera) and cinnamon (Cassia, Cinnamomum) using an in vitro static digestion system based on human gastrointestinal physiologically relevant conditions. Also, in vitro inhibitory effects of these foods on lipid (lipase) and carbohydrate digestive enzymes (α-amylase and α-glucosidase) were performed with before and after digested samples using acarbose and methylumbelliferyl oleate (4MUO) as the positive control. While the highest total anthocyanin content was found in red grape (164 ± 2.51 mg/100 g), the highest procyanidin content was found in cinnamon (6432 ± 177.31 mg/100 g) (p < 0.05). The anthocyanin bioaccessibilities were found as 10.2 ± 1%, 8.23 ± 0.64%, and 8.73 ± 0.70% in apple, red grape, and cinnamon, respectively. The procyanidin bioaccessibilities of apple, red grape, and cinnamon were found as 17.57 ± 0.71%, 14.08 ± 0.74% and 18.75 ± 1.49%, respectively. The analyzed apple, red grape and cinnamon showed the inhibitory activity against α-glucosidase (IC50 544 ± 21.94, 445 ± 15.67, 1592 ± 17.58 µg/mL, respectively), α-amylase (IC50 38.4 ± 7.26, 56.1 ± 3.60, 3.54 ± 0.86 µg/mL, respectively), and lipase (IC50 52.7 ± 2.05, 581 ± 54.14, 49.6 ± 2.72 µg/mL), respectively. According to our results apple, red grape and cinnamon have potential to inhibit of lipase, α-amylase and α-glucosidase digestive enzymes.

A Review of Factors Affecting Anthocyanin Bioavailability: Possible Implications for the Inter-Individual Variability.

Anthocyanins are dietary bioactive compounds showing a range of beneficial effects against cardiovascular, neurological, and eye conditions. However, there is, as for other bioactive compounds in food, a high inter and intra-individual variation in the response to anthocyanin intake that in many cases leads to contradictory results in human trials. This variability could be caused at two levels, one at the bioavailability level and the other at the effect and mechanisms of action. In this context, we have thoroughly reviewed the scientific literature on anthocyanins variability caused by variation in bioavailability. Based on the literature reviewed, we have concluded that the variability in anthocyanins bioavailability might be produced by the lack of homogeneity introduced at three different levels: food matrix and food processing, enzymes involved in anthocyanin metabolism and transport, and anthocyanin metabolizing gut microbiota. However, it should be noted that the literature on anthocyanins bioavailability considering inter or intra-individual variability is still very scarce, which makes it difficult to reach any firm conclusion on the main metabolizing enzymes or bacteria that would be responsible for the variability in anthocyanin bioavailability.

Monitoring molecular composition and digestibility of ripened bresaola through a combined foodomics approach.

In this work, the effects of maturation time and simulated gastrointestinal digestion on the molecular and peptide profiles of "Bresaola Valtellina" were assessed through the foodomics approach, in this case food proteomics and peptidomics combined to other analytical and biological assays, aiming at depicting a holistic food quality. Human digestion of this Italian cured meat product was simulated using an in vitro static protocol and the degree of proteolysis and the in vitro bioactivity of the soluble free compounds in the digestates were evaluated by biochemical assays, e.g. SDS-PAGE, size exclusion HPLC, HPLC/MS, 1H NMR, enzymatic and antioxidant activities. The obtained results demonstrated that in vitro gastrointestinal digestion contributed to a considerable release of myofibrillar proteins by the muscle tissue. Data from SDS-PAGE, peptidomic and size exclusion HPLC assays showed that the in vitro digestion largely degraded proteins of muscle tissue to peptides smaller than 250 Da. The released peptides were likely responsible for the inhibitory activity on amylolytic enzymes and for the antioxidant properties elicited by the gastric digestates of Bresaola. Overall, the results demonstrated the negligible role of ripening in making meat proteins more bioaccessible, whereas they confirmed the highly in vitro digestibility of meat proteins from Bresaola. This study represents a new approach merging proteomics and foodomics to evaluate the effect of ripening and in vitro digestion on the bioactivity and bioaccessibility of proteins and peptides of meat products.

Bioaccessibility and inhibitory effects on digestive enzymes of carnosic acid in sage and rosemary.

In this study, the aim was to determine the bioaccessibilities of carnosic acid in sage and rosemary and in vitro inhibitory effects of these samples on lipid and starch digestive enzymes by evaluating the lipase, α-amylase and α-glucosidase enzyme inhibition activities. The content of carnosic acid in rosemary (18.72 ±â€¯0.33 mg/g) was found to be higher than that content of that in sage (3.76 ±â€¯0.13 mg/g) (p < 0.05). The carnosic acid bioaccessibilities were found as 45.10 ±â€¯1.88% and 38.32 ±â€¯0.21% in sage and rosemary, respectively. The tested sage and rosemary showed inhibitory activity against α-glucosidase (Concentration of inhibitor required to produce a 50% inhibition of the initial rate of reaction - IC50 88.49 ±â€¯2.35, 76.80 ±â€¯1.68 µg/mL, respectively), α-amylase (IC50 107.65 ±â€¯12.64, 95.65 ±â€¯2.73 µg/mL, respectively) and lipase (IC50 6.20 ±â€¯0.63, 4.31 ±â€¯0.62 µg/mL, respectively). Furthermore, to the best of our knowledge, this is the first work that carnosic acid standard equivalent inhibition capacities (CAEIC50) for these food samples were determined and these values were in agreement with the IC50 values. These results show that sage and rosemary are potent inhibitors of lipase, α-amylase and α-glucosidase digestive enzymes.

Stability and bioaccessibility of anthocyanins in bakery products enriched with anthocyanins.

Anthocyanins, water soluble polyphenols, have been associated with several beneficial health effects. The aim of this study was to determine how the baking process and food matrix affect anthocyanin stability and bioaccessibility in bakery products in order to develop functional foods. Three well known regularly consumed bakery products (buns, breadsticks and biscuits) were enriched with anthocyanin (AC) isolated from grape skin alone or in combination with docosahexaenoic acid (AC + DHA) to reveal knowledge on AC as active ingredients in real food systems rather than pure compounds. Anthocyanin amounts added to the formulations of buns, breadsticks and biscuits were 34 mg per 100 g, 40 mg per 100 g and 37 mg per 100 g, respectively. The effect of processing, storage and the food matrix on AC stability and bioaccessibility was investigated. In addition, the sensory properties of bakery products were evaluated. Breadsticks enriched with AC and AC + DHA received the lowest scores in the pre-screening sensory test. Therefore breadsticks were excluded from further analysis. AC retentions, which were monitored by determination of malvidin 3-O-glucoside, in the bun and biscuit after baking were 95.9% (13.6 mg per 100 g) and 98.6% (15.2 mg per 100 g), respectively. Biscuits and buns enriched only with AC showed significantly higher anthocyanin bioaccessibilities (57.26% and 57.30%, respectively) than the same ones enriched with AC + DHA. AC stability in enriched products stored for 21 days was significantly lower than in products stored for 7 days (p < 0.05). However, this loss can be accepted as negligible since more than 70% of AC was retained in all the products.

Inhibitory effects of chickpea and Tribulus terrestris on lipase, α-amylase and α-glucosidase.

The total saponin content and its in vitro bioaccessibilities in Tribulus terrestris and chickpea were determined by a static in vitro digestion method (COST FA1005 Action INFOGEST). Also, in vitro inhibitory effects of the chosen food samples on lipid and starch digestive enzymes were determined by evaluating the lipase, α-amylase and α-glucosidase activities. The tested T. terrestris and chickpea showed inhibitory activity against α-glucosidase (IC50 6967 ± 343 and 2885 ± 85.4 µg/ml, respectively) and α-amylase (IC50 343 ± 26.2 and 167 ± 6.12 µg/ml, respectively). The inhibitory activities of T. terrestris and chickpea against lipase were 15.3 ± 2.03 and 9.74 ± 1.09 µg/ml, respectively. The present study provides the first evidence that these food samples (T. terrestris, chickpea) are potent inhibitors of key enzymes in digestion of carbohydrates and lipids in vitro.

Vegetable product containing caseinomacropeptide and germinated seed and sprouts.

In this study vegetable product containing germinated seed and sprouts of lentils and cowpeas, and caseinomacropeptide isolated from whey is produced. Three different forms of vegetable product namely puree (VP), freeze-dried (FD) and drum-dried (DD) are produced. Freeze-dried and DD forms are produced to diversify forms of utilization and to improve functionality such as increased shelf life and decreased storage space. Their beneficial effects on health are determined using in vitro methods. All forms displayed antioxidant activities against DPPH radical and oxygen radical, α-amylase inhibitory activities, bile acid binding capacities, and angiotension converting enzyme (ACE) inhibitory activities. Freeze-dried product exhibited the strongest inhibition on α-amylase and ACE with the IC50 value 0.09 µM total phenolic and 0.82 mg protein/g sample, respectively when evaluated on the basis of serving size.

Microwave-assisted hydrodistillation of essential oil from rosemary.

Effects of microwave assisted hydrodistillation (MAHD) and conventional hydrodistillation (HD) methods on yield, composition, specific gravity, refractive index, and antioxidant and antimicrobial activities of essential oil of Rosmarinus officinalis L were studied. The main aroma compounds of rosemary essential oil were found as 1,8-cineole and camphor. Trolox equivalent antioxidant capacity (TEAC) values for essential oils extracted by MAHD and HD were 1.52 mM/ml oil and 1.95 mM/ml oil, respectively. DPPH radical scavenging activity of the oils obtained by MAHD and HD were found as 60.55% and 51.04% respectively. Inhibitory effects of essential oils obtained by two methods on linoleic acid peroxidation were almost the same. Essential oils obtained by two methods inhibited growth of Esherichia coli O157:H7, Salmonella typhimurium NRRLE 4463 and Listeria monocytogenes Scott A with the same degree. However, inhibitory activity of essential oil obtained by MAHD on Staphylococcus aureus 6538P was stronger than that of obtained by HD (p < 0.05).

Vegetable and fermented vegetable juices containing germinated seeds and sprouts of lentil and cowpea.

Health-promoting effects of vegetable juice (VJ) and fermented vegetable juice (FVJ) were determined. Both juices displayed antioxidant activity against DPPH radical, and ORAC values obtained for both juices were not statistically different. The α-glucosidase inhibitory activities of the VJ and FVJ were not different. However, α-amylase inhibitory effect of the VJ (IC50: 41µM) was higher than that of FVJ (IC50: 149µM) (p<0.05). In vitro bile acid-binding capacity of FVJ was about 4.30times higher than that of VJ (p<0.05). Although in vitro ACE inhibitory activity of VJ was below 50%, FVJ displayed ACE inhibition (80.2%) with an IC50 value of 50µgprotein/ml. Even though ACE inhibitory activities of digested and undigested FVJ were similar, there was a 42-fold decrease in the IC50 value of FVJ after small intestinal digestion (p<0.05). FVJ, diluted by one half, displayed hemagglutinating activity whilst VJ did not display any hemagglutinating activity.

Production of resistant starch from taro (Colocasia esculenta L. Schott) corm and determination of its effects on health by in vitro methods.

The aim of the study was the production of resistant starch from taro (Colocasia esculenta L. Schott) corm and determination of its effects on health by in vitro methods. Starch was isolated from taro corms with 98% purity, and 10.4±0.5% amylose content. By application of heating, autoclaving, enzymatic debranching, retrogradation, and drying processes to taro starch for two times, resistant starch (RS) content was increased 16 fold (35.1±1.9%, dry basis). The expected glycemic index (eGI) of taro starch and taro resistant starch was determined as 60.6±0.5 and 51.9±0.9, respectively and the decrease in the glycemic index of taro resistant starch was found as statistically significant (P<0.05). The in vitro binding of bile acids by taro starch and taro resistant starch relative to cholesterol decreasing drug cholestyramine were 5.2±0.2% and 7.6±1.7%, respectively.

Antioxidant and antimicrobial activities of essential oils obtained from oregano (Origanum vulgare ssp. hirtum) by using different extraction methods.

In this study, antioxidant and antimicrobial activities of essential oils obtained from oregano (Origanum vulgare ssp. hirtum) were determined by using solvent-free microwave extraction (SFME), supercritical fluid extraction, and conventional hydrodistillation (CH) methods. The inhibitory effects on the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical of essential oils obtained from oregano by using SFME and CH were similar. However, essential oil extracted by CH showed greater (2.69 µmol/µL of oil) Trolox equivalent antioxidant capacity (TEAC) than oregano oils obtained by SFME (P < .05). The difference between percentage inhibition and TEAC values most probably is due to the fact that undiluted and diluted samples are used in the percentage inhibition assay and the TEAC assay, respectively. TEAC values of oregano essential oils obtained by SFME at different microwave power levels were found to be similar and ranged from 0.72 to 0.84 µmol/µL of oil. Essential oils obtained by CH and SFME at different microwave powers inhibited the survival of Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli O157:H7, whereas survival of Staphylococcus aureus was not influenced. In addition, oregano oil obtained by SFME at 40% power level did not show any inhibitory effect on E. coli O157:H7.

Determination of in vitro antidiabetic effects, antioxidant activities and phenol contents of some herbal teas.

In this research, some herbal teas and infusions traditionally used in the treatment of diabetes in Turkey, have been studied for their antidiabetic effects on in vitro glucose diffusion and phenolic contents and antioxidant activities. Ten aqueous herbal tea extracts were examined using an in vitro method to determine their effects on glucose movement across the gastrointestinal tract. Total phenol content of herbal teas was analyzed by Folin-Ciocalteu's procedure. Antioxidant activities of herbal teas were evaluated by the effect of extracts on DPPH radical and hydrogen peroxide scavenging. Antioxidant activity was defined as the amount of the sample to decrease the initial DPPH concentration by 50% as efficient concentration, EC50. Antiradical activity [AE] was calculated as 1/EC50. Values were evaluated statistically. Results support the view that none of the herbal teas showed antidiabetic effect on glucose diffusion using in vitro model glucose absorption. Teas were arranged in the order of green tea > peppermint > thyme > black tea > relax tea > absinthium > shrubby blackberry > sage > roselle > olive leaves according to their total phenol contents. Among ten herbal teas, green tea had the highest hydrogen-donating capacity against to DPPH radical. Ranking of the herbal teas with respect to their DPPH radical scavenging activity were green tea > peppermint > black tea > thyme > relax tea > absinthium > roselle > olive leaves > sage > shrubby blackberry. It was determined that adding flavoring substances such as lemon, bergamot, clove and cinnamon, which are commonly used in preparation of black tea in Turkey resulted to have synergistic effect on total antioxidant activities of black and peppermint teas. The highest hydrogen peroxide inhibition value (65.50%) was obtained for green tea at a 250 microl/ml concentration. The H2O2 scavenging activity of herbal teas decreased in the order green tea > peppermint > relax tea > black tea > thyme > olive leaves > sage > absinthium > shrubby blackberry > roselle. In particular, their phenolic compounds and antioxidant activities may be useful for meal planning in type 2 diabetes. They could contribute to sustain plasma antioxidant level because antioxidants present in plants and herbs prevent the development of vascular diseases seen in type 2 diabetes.

Primary oral cancer in a Turkish population sample: association with sociodemographic features, smoking, alcohol, diet and dentition.

The aim of this multicentre case-control study was to investigate the association of a variety of factors with oral cancer in a group of Turkish patients. Questionnaires were used to investigate the sociodemographic features, smoking and alcohol consumptions, dietary habits and dental status of 79 primary oral cancer patients and 61 controls. Data were statistically analysed with Mann-Whitney U-test, Pearson Chi-square and binary logistic regression analyses to determine the odds ratios. Low level of education, gender, dietary habits, having poor oral hygiene and denture sores were associated with primary oral cancer in this patient sample; but eating salads and raw vegetables, fish, and drinking red wine were related with healthy status. Determination of the factors associated with oral cancer and of the high-risk groups would be beneficial to provide efficient screening protocols and prevention programmes for oral cavity cancers.

In vitro determination of calcium bioavailability of milk, dairy products and infant formulas.

In this study, the aim was to determine the in vitro calcium bioavailability of different dairy products and to investigate the effect of dry matter, fat, acidity and calcium content on calcium bioavailability of the products. For this purpose, the dry matter, fat, acidity and calcium content of different kinds of milk, yogurt, cheese and infant formulas were analysed. Then, calcium bioavailability of products was determined by an in vitro method that involves simulating gastrointestinal digestion of the product with pepsin-HCl and pancreatin-biliary salts, and then measuring the fraction of element that dialyses through a membrane of a certain pore size. Each of the product groups was examined statistically and no difference was found among milk, yogurt and infant formula groups in terms of calcium bioavailability. However, there were differences among cheese kinds according to the results of the Duncan test; all cheese kinds were considerably different from each other (P < 0.05). Moreover, it was found that calcium, dry matter, fat content and acidity did not affect the calcium bioavailability (P < 0.05). According to the results of statistical analysis that was applied to all product groups, it was found that the yogurt group was different from the other products and that the acidity affected calcium bioavailability (P < 0.05).

Effects of drying process on antioxidant activity of purple carrots.

Purple carrot was analysed for its antioxidant activity by measuring its scavenging effect on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. The amount of purple carrot necessary to decrease by 50% the initial DPPH concentration (EC50) was found 30.23 +/- 5.17 (mg sample/mg DPPH). Effects of the dehydration process on the antioxidant activity of purple carrots were also determined after dehydration by using tray drier and microwave+tray drier combination. Purple carrots were cleaned, washed, sorted, sliced, and blanched in water at 98 +/- 1 degree C for 2 min. Then half of the samples were dehydrated in microwave (45 min) and tray drier (105 min) combination, and others were dehydrated in tray drier (150 min) until reaching the constant weight. Raw, blanched and dehydrated purple carrots were compared for their antioxidant activity and total anthocyanin contents, color values (L*, a*, b*, C*, H degrees) and dry matter contents. The antioxidant activity as measured by DPPH, EC50 value ranged from 7.80 to 30.23 of processed and raw carrots where the H degrees values were changed from -3.68 to -23.96 corresponding to a bluish hue.

Radical scavenging and iron-chelating activities of some greens used as traditional dishes in Mediterranean diet.

This study aimed at evaluating the antioxidative activity of nine different families of greens. Raphanus raphanistrum (wild radish), Anchusa azurea (bugloss), Daucus carota (wild carrot), Sonchus oleraceus (sowthistle), Papaver rhoeas (corn poppy), Malva sylvestris (blue mallow), Foeniculum vulgare (fennel), Cichorium intybus (chicory) and Salicornia europaea (jointed glasswort) are native to the Mediterranean and are commonly consumed as a salad or an ingredient in some recipes. The antioxidative activities, including the radical scavenging effects, inhibition of hydrogen peroxide (H(2)O(2)), and Fe(2+)-chelating activity, were studied. All samples showed antioxidant activity as a radical scavenger in the experiment using the DPPH* radical. The ratio between the slopes of the kinetic model was used to compare antioxidant efficiency of different greens. Greens also possessed antioxidative activity toward H(2)O(2). Especially, greens exhibited a marked scavenging effect on H(2)O(2) at 0.2 g/ml concentration. The Fe(2+) ion-chelating activities of the samples except jointed glasswort were greater than 70%. The antioxidant activity of samples with different methods based on the inhibition of different reactions could not be compared. The current dietary guidelines include recommendations for an increase in the consumption of plant foods. Greens should provide an optimal supply of antioxidant substances in the diet.