In vitro bioaccessibility of health-related compounds as affected by the formulation of fruit juice- and milk-based beverages

Unlocking Quercetin's Neuroprotective Potential: A Focus on Bee-Collected Pollen

In the quest to evade side effects associated with synthetic drugs, mankind is continually exploring natural sources. In recent decades, neurodegenerative disorders (NDDs) have surged dramatically compared to other human diseases. Flavonoids, naturally occurring compounds, have emerged as potential preventers of NDD development. Notably, quercetin and its derivatives demonstrated excellent antioxidant properties in the fight against NDDs. Recognizing bee-collected pollen (BP) as a well-established excellent source of quercetin and its derivatives, this review seeks to consolidate available data on the prevalence of this flavonoid in BP, contingent upon its botanical and geographical origins. It aims to advocate for BP as a superb natural source of "drugs" that could serve as preventative measures against NDDs. Examination of numerous published articles, detailing the phenolic profile of BP, suggests that it can be a great source of quercetin, with an average range of up to 1000 mg/kg. In addition to quercetin, 24 derivatives (with rutin being the most predominant) have been identified. Theoretical calculations, based on the recommended dietary intake for quercetin, indicate that BP can fulfil from 0.1 to over 100 % of the requirement, depending on BP's origin and bioaccessibility/bioavailability during digestion.

Bioaccessibility and antioxidant capacity of kefir-based smoothies fortified with kale and spinach after in vitro gastrointestinal digestion

The kefir-based smoothies with kale and spinach were designed as a ready-to-drink and innovative functional snack. Microbiological, physicochemical, as well as pre- and postgastrointestinal total antioxidant capacity (TAC; CUPRAC, DPPH, and FRAP) analyses were conducted. It was determined that the kefir-based smoothies with vegetables had higher ash, carbohydrate, and dietary fiber values. Fructose and glucose contents of smoothy with kale were high, while smoothy with spinach included high sucrose and maltose. The microbiology results revealed that kefir-based vegetable smoothies had minimum Lactobacillaceae viability (>log 7 cfu g-1) for the required functional effect after 14-day storage. Moreover, the addition of kale significantly increased (p < .01) the level of initial TAC (CUPRAC, DPPH, and FRAP) and total phenolic content (TPC) values. After in vitro gastric digestion analysis, smoothie with spinach demonstrated higher TAC and TPC values and the control sample had higher TAC and TPC values compared with a predigestion step. It was found that in vitro intestinal DPPH values were higher for the sample with spinach samples, while the sample with kale had the highest FRAP values. It was also found that the bioaccessibility indexes of plain kefir were determined to be the highest in both in vitro gastric and intestinal procedures. The present study provided novel insights into the in vitro digestion properties of kefir fortified with vegetables. Nevertheless, further studies are needed to identify the functional properties of the milk and plant matrices mixture using in vitro and in vivo trials.

Effects of adding milk to fermented black mulberry (Morus nigra L.) juice on its antioxidant activity in C2C12 cells and changes in volatile flavor compounds during storage

This study assessed the impact of milk on the bioactive compounds, physicochemical properties, antioxidant activity, ROS inhibition, and volatile flavor compounds of fermented black mulberry juice (FBMJ). Firstly, the results showed that 25% concentration of milk was the most suitable for preparing FBMJ-Milk. Compared to the control group, the addition of milk significantly increased the SOD activity and antioxidant capacity, as well as enhanced the total phenolic content (TPC) and SOD storage stability. Secondly, HS-SPME-GC-MS combined with OPLS-DA analysis identified 49 compounds in FBMJM, including 12 esters, 6 acids, 1 ketone, 2 aldehydes, 19 alcohols and 9 other compounds. During the storage, the levels of ethyl ester compounds decreased significantly, while the degradation of ester produced some acid and alcohol compounds. The findings revealed that the addition of milk was beneficial for maintaining the antioxidant stability of FBMJM during storage and enhancing the richness of product flavor.

Oral bioavailability of bioactive compounds; modulating factors, in vitro analysis methods, and enhancing strategies

Foods are complex biosystems made up of a wide variety of compounds. Some of them, such as nutrients and bioactive compounds (bioactives), contribute to supporting body functions and bring important health benefits; others, such as food additives, are involved in processing techniques and contribute to improving sensory attributes and ensuring food safety. Also, there are antinutrients in foods that affect food bioefficiency and contaminants that increase the risk of toxicity. The bioefficiency of food is evaluated with bioavailability which represents the amount of nutrients or bioactives from the consumed food reaching the organs and tissues where they exert their biological activity. Oral bioavailability is the result of some physicochemical and biological processes in which food is involved such as liberation, absorption, distribution, metabolism, and elimination (LADME). In this paper, a general presentation of the factors influencing oral bioavailability of nutrients and bioactives as well as the in vitro techniques for evaluating bioaccessibility and is provided. In this context, a critical analysis of the effects of physiological factors related to the characteristics of the gastrointestinal tract (GIT) on oral bioavailability is discussed, such as pH, chemical composition, volumes of gastrointestinal (GI) fluids, transit time, enzymatic activity, mechanical processes, and so on, and the pharmacokinetics factors including BAC and solubility of bioactives, their transport across the cell membrane, their biodistribution and metabolism. The impact of matrix and food processing on the BAC of bioactives is also explained. The researchers' recent concerns for improving oral bioavailability of nutrients and food bioactives using both traditional techniques, for example, thermal treatments, mechanical processes, soaking, germination and fermentation, as well as food nanotechnologies, such as loading of bioactives in different colloidal delivery systems (CDSs), is also highlighted.

Implication of the Polymeric Phenolic Fraction and Matrix Effect on the Antioxidant Activity, Bioaccessibility, and Bioavailability of Grape Stem Extracts

The bioaccessibility and bioavailability of phenolics compounds of two grape stem extracts with different composition were studied. High polymeric extract (HPE) presented a higher content of total phenolics (TPC), procyanidins, hemicelluloses, proteins, and ashes, whereas low procyanidin extract (LPE) showed a higher fat, soluble sugars, and individual phenolic compounds content. Corresponding to its higher total phenolics content, HPE possesses a higher antioxidant activity (TEAC value). The digestion process reduced the antioxidant activity of the HPE up to 69%, due to the decrease of TPC (75%) with a significant loss of polymeric compounds. LPE antioxidant activity was stable, and TPC decreased by only 13% during the digestion process. Moreover, a higher antioxidant phenolic compounds bioavailability was shown in LPE in contrast to HPE. This behaviour was ascribed mainly to the negative interaction of polymeric fractions and the positive interaction of lipids with phenolic compounds. Therefore, this study highlights the convenience of carrying out previous studies to identify the better extraction conditions of individual bioavailable phenolic compounds with antioxidant activity, along with those constituents that could increase their bioaccessibility and bioavailability, such as lipids, although the role played by other components, such as hemicelluloses, cannot be ruled out.

Impact of gastrointestinal digestion simulation on brewer's spent grain green extracts and their prebiotic activity

Brewer's spent grain (BSG) is a by-product of the beer industry and a potential source of bioactive compounds. In this study, two methods of extracting bioactive compounds from brewer's spent grain were used - solid-to-liquid conventional extraction (SLE) and solid-to-liquid ohmic heating extraction (OHE) coupled with two ratio combinations of solvents: 60 % and 80 % ethanol:water (v/v). The bioactive potential of the BSG extracts was assessed during the gastrointestinal tract digestion (GID) and the differences in their antioxidant activity, total phenolic content and characterization of the polyphenol profile was measured. The SLE extraction using 60 % ethanol:water (v/v) was the extraction method with higher antioxidant activity (33.88 mg ascorbic acid/g BSG - initial; 16.61 mg ascorbic acid/g BSG - mouth; 15.58 mg ascorbic acid/g BSG - stomach; 17.26 mg ascorbic acid/g BSG - duodenum) and higher content in total phenolics (13.26 mg gallic acid/g BSG - initial; 4.80 mg gallic acid/g BSG - mouth; 4.88 mg gallic acid/g BSG - stomach; 5.00 mg gallic acid/g BSG - duodenum). However, the OHE extraction using 80 % ethanol:water (v/v), had a higher bioaccessibility index (99.77 % for ferulic acid, 72.68 % for 4-hydroxybenzoic acid, 65.37 % for vanillin, 28.99 % for p-coumaric, 22.54 % for catechin) values of polyphenols. All the extracts enhanced (except for SLE for 60 % ethanol:water (v/v) at 2 and 1.5 %, and for 80 % ethanol:water (v/v) at 2 % with Bifidobacterium animalis spp. lactis BB12, where no growth was observed) the growth of the probiotic microorganisms tested (Bifidobacterium animalis B0 - O.D.'s between 0.8240 and 1.7727; Bifidobacterium animalis spp. lactis BB12 - O.D.'s between 0.7219 and 0.8798; Lacticaseibacillus casei 01 - O.D.'s between 0.9121 and 1.0249; and Lactobacillus acidophilus LA-5 - O.D.'s between 0.8595 and 0.9677), demonstrating a potential prebiotic activity of BSG extracts.

In Vitro Gastrointestinal Digestion Affects the Bioaccessibility of Bioactive Compounds in Hibiscus sabdariffa Beverages

Hibiscus sabdariffa possess great versatility to be used as an ingredient for a whole range of products with natural-based ingredients, which are growing in popularity due to the health benefits of bioactive compounds (BC). Therefore, the objective of this study was to characterize the BC content in Hibiscus beverages and to evaluate their in vitro bioaccessibility. Results showed significant differences (p < 0.05) in the total contents of BC prior to the in vitro intestinal digestion. Hibiscus acid was the most abundant compound identified. Thirty-five compounds were identified in the Hibiscus beverage at the initial stage, while a maximum of 15 compounds were quantified in the different fractions of gastrointestinal digestion. After digestion, significant differences were found compared with the initial content of BC. That phenolic acids were the less bioaccessible group, while flavonoids were the most diverse. Principal components analysis showed different clusters and changes in the profiles of BC present at the initial stage and those bioaccessible, showing that intestinal digestion significantly affects the BC profile of the beverage.

Stability and antioxidant activity of phenolic compounds during in vitro digestion

The impact of phenolic compounds on the human body depended on the type, content, bioavailability, and antioxidant activity. After digestion, different phenolic compounds had different changes of bioavailability and antioxidant activity, which needed to be considered in the application. In this experiment, the structural stability and antioxidant activity of 27 phenolic compounds (phenolic acids, flavonols, flavonoids, and flavanones) were investigated during the in vitro simulated digestion. This experiment eliminated the influence of food matrix, provide a basis for regularity for the changes of phenolic substances in different materials. Results showed that the bioaccessibility of phenolic compounds with different structures varied, and there was a conformational relationship between the structure and stability. After oral digestion, most of the phenolic compounds underwent degradation and the cellular antioxidant activity (CAA) values decreased to a large extent (p < 0.05). After gastric digestion, the content (p > 0.05) and CAA values (p < 0.05) of most phenolic compounds increased. However, after intestinal digestion, the phenolic compounds were degraded to a greater extent, and different structures of phenolic compounds had different changes in CAA values (p < 0.05). In general, the CAA values of most phenolic compounds after in vitro digestion were lower than the initial value. The 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ehylbenzthiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) values of phenolic acids and flavonols decreased after in vitro simulated digestion (p < 0.05), while the values of DPPH, ABTS, and FRAP of most flavonoids (p < 0.05) increased. The increased oxygen radical absorption capacity (ORAC) values were found in most phenolic acids, flavonols, and flavonoids (p < 0.05), and most flavanones showed unremarkable changes in ORAC values (p > 0.05). In general, the changing trend of chemical-based antioxidant activity was consistent with the content of phenolic compounds.

Formulation of Functional Drink with Milk Fortification: Effects on the Bioaccessibility and Intestinal Absorption of Phenolics

Due to a turn toward to functional foods with improved nutritional value, rosehip could be an appropriate candidate to create formulations using a milk matrix. In the present study, the influence of bovine or almond milk fortification on the bioaccessibility and intestinal absorption of rosehip infusion phenolics, mainly catechin, were investigated by a combined method of an in vitro gastrointestinal digestion/Caco-2 cell culture model. The results indicated that bovine (IB) or almond milk (IA) fortification enhanced the retention of total phenolics (TPC; increase of 8.1% and 20.3% for IB and IA, respectively), while there was a decline in the total flavonoids (TFC; decrease of 64% and 17% for IB and IA, respectively) and antioxidant capacity measured by CUPRAC assay (decrease of 15% and 4% for IB and IA, respectively) throughout the gastrointestinal tract in comparison with the control sample (IC). Then, based on the cytotoxicity (SRB) assay, 1/5 times diluted digests were subjected to transepithelial transportation of Caco-2 cells. According to the results, the bovine milk matrix positively affected the transportation of phenolics across the epithelial cell layer. It could be concluded that it is possible to produce functional infusion drinks with improved stability, bioaccessibility, and absorption efficiency of rosehip phenolics in the formulations containing milk matrix.

Bioaccessibility of Phenolic Compounds and Antioxidant Properties of Goat-Milk Powder Fortified with Grape-Pomace-Seed Extract after In Vitro Gastrointestinal Digestion

This study deals with the evaluation of the bioaccessibility and antioxidant properties of phenolic compounds from heat-treated skim goat-milk powder fortified with grape-pomace-seed extract, after in vitro gastrointestinal digestion. Ultra-high performance liquid chromatography coupled to diode array detection and mass spectrometry (UHPLC-DAD MS/MS) analysis confirmed the abundant presence of phenolic acids and flavan-3-ols in the grape-pomace-seed extract (SE) and heat-treated skim goat-milk/seed-extract powder (TME). After in vitro digestion of TME powder and recovery of total quantified phenolics, flavan-3-ols and phenolic acids were 18.11%, 24.54%, and 1.17%, respectively. Low recovery of grape-pomace-seed phenolics indicated strong milk protein-phenolic interactions. Electrophoretic analysis of a soluble fraction of digested heat-treated skim goat milk (TM) and TME samples showed the absence of bands originating from milk proteins, indicating their hydrolysis during in vitro gastrointestinal digestion. The digested TME sample had better antioxidant properties in comparison to the digested TM sample (except for the ferrous ion-chelating capacity, FCC), due to the presence of bioaccessible phenolics. Taking into account the contribution of the digestive cocktail, digested TME sample had lower values of total phenolic content (TPC), in vitro phosphomolybdenum reducing capacity (TAC) and ferric reducing power (FRP), compared to the undigested TME sample. These results could be attributed to low recovery of phenolic compounds. TME powder could be a good carrier of phenolics to the colon; thus, TME powder could be a promising ingredient in the formulation of functional food.

Assessment of in vitro bioaccessibility of carotenoids and phenolic compounds in a model milk-mandarine beverage

Mandarine juice is one of the richest sources of β-cryptoxanthin and flavonoids, which have been positively associated with bone mineral density. Carotenoids are lipophilic isoprenoid compounds with a complex absorption process that can be affected by different factors. In this study, we have evaluated the effect of the food matrix on the in vitro bioaccessibility of carotenoids and phenolic compounds in a model milk-mandarine beverage (MMB). MMBs were formulated with mandarine juice and different dairy products to achieve three fat levels (0.2%, 1.7% and 3.2%) and three calcium levels (120, 310 and 500 mg Ca²⁺ per 100 ml). The bioaccessibility was evaluated using a harmonised in vitro digestion method. The results showed that the content of milk fat increased the bioaccessibility in vitro of phenolic compounds (p < 0.05), while a moderate fat level (1.7%) resulted in the highest bioaccessibility for bioactive carotenoids. On the other hand, calcium fortification at the highest level (500 mg Ca²⁺ per 100 mL) decreased the bioaccessibility of bioactive carotenoids from 76% to 43% (66% for the major β-cryptoxanthin) compared to the lower calcium fortification level (120 mg Ca²⁺ per 100 mL). The bioaccessibility of hesperidin, the main flavanone in mandarine juice, was significantly (p < 0.05) reduced in the MMB with the highest calcium level. The bioaccessibility of carotenoids and phenolic compounds is affected by fat and calcium levels. When formulating functional beverages, the impact of the formulation should be carefully considered to optimize the bioaccessibility of the bioactive compounds.

The Role of Gut Microbiota Modulation Strategies in Obesity: The Applications and Mechanisms

Nowadays, obesity is a leading public health problem worldwide. The growing prevalence of obesity significantly accounts for other cardio-metabolic diseases, including hypertension and diabetes. Several studies have shown that obesity is strongly associated with genetic, environmental, lifestyle, and dietary factors, especially the disordered profiles of gut microbiota (GM). The present review concluded mechanistic studies and potential correspondent treatments for obesity. Specifically, the anti-obesity effects of food-derived compounds manipulating GM were highlighted. The potential limitations of bioactive compounds on absorption in the intestinal tract were also discussed. Thus, the future direction of fecal microbiota transplantation (FMT) as an approach to support modulating host GM (considered to be a potential therapeutic target for obesity) was discussed. This review shed light on the role of GM modulation strategies for the prevention/treatment of obesity.

Impact of Circular Brewer’s Spent Grain Flour after In Vitro Gastrointestinal Digestion on Human Gut Microbiota

Brewer’s spent grain (BSG) solid residues are constituted by dietary fibre, protein, sugars, and polyphenols, which can have potential effects on human health. In this study, for the first time, the flours obtained from solid residues of solid-liquid extraction (SLE) and ohmic heating extraction (OHE) were applied throughout the gastrointestinal digestion simulation (GID), in order to evaluate their prebiotic potential and in vitro human gut microbiota fermentation. The results showed that the digestion of BSG flours obtained by the different methods lead to an increase throughout the GID of total phenolic compounds (SLE: from 2.27 to 7.20 mg gallic acid/g BSG—60% ethanol:water (v/v); OHE: 2.23 to 8.36 mg gallic acid/g BSG—80% ethanol:water (v/v)) and consequently an increase in antioxidant activity (ABTS—SLE: from 6.26 to 13.07 mg ascorbic acid/g BSG—80% ethanol:water (v/v); OHE: 4.60 to 10.60 mg ascorbic acid/g BSG—80% ethanol:water (v/v)—ORAC—SLE: 3.31 to 14.94 mg Trolox/g BSG—80% ethanol:water (v/v); OHE: from 2.13 to 17.37 mg Trolox/g BSG—60% ethanol:water (v/v)). The main phenolic compounds identified included representative molecules such as vanillic and ferulic acids, vanillin and catechin, among others being identified and quantified in all GID phases. These samples also induced the growth of probiotic bacteria and promoted the positive modulation of beneficial strains (such as Bifidobacterium spp. and Lactobacillus spp.) present in human faeces. Moreover, the fermentation by human faeces microbiota also allowed the production of short chain fatty acids (acetic, propionic, and butyric). Furthermore, previous identified polyphenols were also identified during fecal fermentation. This study demonstrates that BSG flours obtained from the solid residues of SLE and OHE extractions promoted a positive modulation of gut microbiota and related metabolism and antioxidant environment associated to the released phenolic compounds.

Spray Drying and Spout-Fluid Bed Drying Microencapsulation of Mexican Plum Fruit (Spondias purpurea L.) Extract and Its Effect on In Vitro Gastrointestinal Bioaccessibility

The Mexican plum (Spondias purpurea L.) is a source of phenolic compounds; however, these compounds are susceptible to various factors (humidity, temperature, light, oxygen), as well as the digestion process, which can modify their bioaccessibility. This study aimed to extract and microencapsulate the phenolic compounds (PC), total anthocyanins (TA), ascorbic acid (AA), dehydroascorbic acid (DHA) and total vitamin C (AA+DHA) from Mexican plum ecotype “Cuernavaqueña” by spray drying (SD) and spout-fluid bed drying (SFB) and evaluate the bioaccessibility of these compounds by in vitro digestion. Optimal extraction conditions for bioactive compounds (BC) and antioxidant capacity (AC) were: three consecutive extractions at 40 °C, for 90 min each, with 1/5 solid-solvent ratio (4 g/20 mL), and 40% v/v aqueous ethanol. The extract without the encapsulation process suffered a significant (p ≤ 0.05) decrease in bioactive compounds and antioxidant capacity after in vitro digestion. Microcapsules obtained by SFB showed better retention and encapsulation efficiencies coupled with better protection against the digestion process. Microencapsulation by SFB protects the BC of Mexican plum, and it could be used in the food industry as ingredient to develop functional foods.

The reciprocal interaction between polyphenols and other dietary compounds: Impact on bioavailability, antioxidant capacity and other physico-chemical and nutritional parameters

Polyphenols are plant secondary metabolites, whose biological activity has been widely demonstrated. However, the research in this field is a bit reductive, as very frequently the effect of individual compound is investigated in different experimental models, neglecting more complex, but common, relationships that are established in the diet. This review summarizes the data that highlighted the interaction between polyphenols and other food components, especially macro- (lipids, proteins, carbohydrates and fibers) and micronutrients (minerals, vitamins and organic pigments), paying particular attention on their bioavailability, antioxidant capacity and chemical, physical, organoleptic and nutritional characteristics. The topic of food interaction has yet to be extensively studied because a greater knowledge of the food chemistry behind these interactions and the variables that modify their effects, could offer innovations and improvements in various fields ranging from organoleptic, nutritional to health and economic field.

Bioaccessibility of terebinth (Pistacia terebinthus L.) coffee polyphenols: Influence of milk, sugar and sweetener addition

In this study, terebinth coffee formulations were prepared with whole or skimmed milk with or without sugar/sweetener in order to study the matrix effect on the bioaccessibility of terebinth polyphenols. Quercetin glycosides and catechin were the major flavonoids identified in the terebinth formulations, whereas gallic, protocatechuic, syringic and ellagic acids were determined as the non-flavonoid compounds. The in vitro gastrointestinal digestion model results revealed that addition of whole milk to terebinth coffee increased the total bioaccessible flavonoids significantly (45%) (p < 0.05), whereas skim milk addition did not result in any significant change. Furthermore, antioxidant capacity results measured with CUPRAC assay showed that addition of milk alone or together with sugar/sweetener increases the bioaccessibility of terebinth coffee antioxidants (36-70%) (p < 0.05). Overall, terebinth coffee + whole milk + sugar formulation was found to contain the highest amount of bioaccessible flavonoid and non-flavonoid compounds (42.71-47.07 mg/100 g).

Effect of in vitro digestion on chestnut outer-skin and inner-skin bioaccessibility: The relationship between biotransformation and antioxidant activity of polyphenols by metabolomics

Chestnut skin is rich in polyphenols that have been linked to health for their antioxidant activity. However, chestnut outer-skin extract (COE), chestnut inner-skin extract (CIE), and their digested products have different compositions of polyphenols, and therefore their antioxidant activities might differ as well. Here, we study the effect of in vitro digestion on their total phenol content, antioxidant capacity, and individual phenolic profile to clarify the relationship between biotransformation and antioxidant activity. Compared to undigested samples, total phenol content and antioxidant activity of digested chestnut outer-skin extract (DCOE) and digested chestnut inner-skin extract (DCIE) had significantly higher values. The changes of phenolic composition and antioxidant activity after digestion were mainly due to the anthocyanin biosynthesis involving glycosylation, acylation, methoxylation and their reverse processes. All these data suggest that as chestnut processing by-products, COE and CIE are raw material sources of antioxidant-rich active substances and need more sufficient utilization.

In Vitro Expanded Bioaccessibility of Quercetin-3-Rutinoside and Quercetin Aglycone from Buckwheat Biscuits Formulated from Flours Fermented by Lactic Acid Bacteria

The expanded bioaccessibility of rutin (Ru) and quercetin (Q) from buckwheat biscuits (BBs) formulated from liquid-state fermented flours by selected lactic acid bacteria (LAB) were determined after gastrointestinal digestion. Fermentation of buckwheat flours caused a LAB-dependent variation in Ru and Q content. BBs baked at 220 °C for 30 min showed lower content of Ru and Q, and no correlation was found between the content of these compounds in fermented flours and BBs. The expanded bioaccessibility of Ru from BBs was low when its content in the soluble and insoluble fractions remaining after digestion in vitro was taken into account. Contrary results were found for Q bioaccessibility which had an index greater than 1, indicating the high Q bioaccessibility from BBs. Since very low Q content was noted in the insoluble fraction remaining after BBs digestion, the high Q bioaccessibility was determined to be due to its concentration in the soluble fraction.

Protective capacity of gum Arabic, maltodextrin, different starches, and fibers on the bioactive compounds and antioxidant activity of an orange puree (Citrus sinensis (L.) Osbeck) against freeze-drying and in vitro digestion

Dehydrated fruit puree may be a convenient way to promote the healthy consumption of fruit based foods. Drying carriers, highly used by the food industry to stabilize dried fruit products, may show a potential encapsulating capacity of the biocompounds, that could also limit their bioaccesibility. This study analyzed the impact of gum Arabic (GA), bamboo fiber (BF), native corn starch, starch substituted with octenylsuccinic groups, pea fiber, and maltodextrin on the in vitro bioaccessibility of vitamin C (VC), total phenols (TP), and β-carotene, as well as on the antioxidant capacity during the freeze-drying and in vitro digestion of an orange puree. Amongst the formulations studied, GA + BF was the most effective for phytochemicals protection of the freeze-dried orange puree during the intestinal stage of digestion, resulting in a higher TP and VC bioaccessibility (59% and 36%, respectively).

Polyphenol bioaccessibility and antioxidant properties of in vitro digested spray-dried thermally-treated skimmed goat milk enriched with pollen

The aim of research was to determine polyphenols bioaccessibility and antioxidant properties of thermally-treated skimmed goat milk enriched with sunflower bee-collected pollen through in vitro digestion. HPLC analysis confirmed that pollen-enriched milk contained flavonols as the main phenolic fraction (80.7-76.2%) followed by phenolic acids (14.2-17.4%). Among individual compounds quercetin-3-O-glucoside (155.1-197.2 μg/L) and p-coumaric acid (29.5-30.7 μg/L) were the main quantified flavonols and phenolic acids, respectively. After digestion of milk/pollen sample, total polyphenols recovery was 30.71% with higher phenolic acids recovery (40.1%) compared to flavonols (28.3%) indicating strong interactions between caprine milk casein micelles and pollen polyphenols. Applied antioxidant assays (phosphomolybdenum, ABTS•⁺scavenging activity and ferrous-ion-chelating capacity) have confirmed complexity of prepared product- it had high ability to quench ABTS•⁺ radicals and to form chelating complexes with Fe²⁺ ions. Digestion provoked 20% reduction in total antioxidant capacity compared to the initial sample. TTSG milk/pollen powder could be good functional ingredient.

Matrix- and Technology-Dependent Stability and Bioaccessibility of Strawberry Anthocyanins during Storage

Anthocyanins are often associated with health benefits. They readily degrade during processing and storage but are also dependent on the matrix conditions. This study investigated how strawberry anthocyanins are affected by preservation technologies and a relatively protein-rich kale juice addition during storage. A strawberry–kale mix was compared to a strawberry–water mix (1:2 wt; pH 4), untreated, thermally, pulsed electric fields (PEF) and high-pressure processing (HPP) treated, and evaluated for anthocyanin stability and bioaccessibility during refrigerated storage. The degradation of strawberry anthocyanins during storage followed first-order kinetics and was dependent on the juice system, preservation technology and anthocyanin structure. Generally, the degradation rate was higher for the strawberry–kale mix compared to the strawberry–water mix. The untreated sample showed the highest degradation rate, followed by HPP, PEF and, then thermal. The relative anthocyanin bioaccessibility after gastric digestion was 10% higher for the thermally and PEF treated samples. Anthocyanin bioaccessibility after intestinal digestion was low due to instability at a neutral pH, especially for the strawberry–kale mix, and after thermal treatment. The storage period did not influence the relative bioaccessibility; yet, the absolute content of bioaccessible anthocyanins was decreased after storage. This research further presents that processing and formulation strongly affect the stability and bioaccessibility of anthocyanins during storage.

Safety of Probiotics: Functional Fruit Beverages and Nutraceuticals

Over the last decade, fruit juice consumption has increased. Their rise in popularity can be attributed to the belief that they are a quick way to consuming a dietary portion of fruit. Probiotics added to fruit juices produce various bioactive compounds, thus probiotic fruit juices can be considered as a new type of functional foods. Such combinations could improve nutritional properties and provide health benefits of fruit juices, due to delivering positive health attributes from both sources (fruit juices and probiotics). However, this review discusses the other side of the same coin, i.e., the one that challenges general beliefs that probiotics are undoubtedly safe. This topic deserves more acknowledgments from the medical and nutritional literature, as it is highly important for health care professionals and nutritionists who must be aware of potential probiotic issues. Still, clinical trials have not adequately questioned the safety of probiotics, as they are generally considered safe. Therefore, this reviews aims to give an evidence-based perspective of probiotic safety, focusing on probiotic fruit beverages and nutraceuticals, by providing documented clinical case reports and studies. Finally, the paper deals with some additional insights from the pharmacological and toxicological point of views, such as pharmacological repercussions of probiotics on health.

Effect of Basil Leaves and Wheat Bran Water Extracts on Antioxidant Capacity, Sensory Properties and Microbiological Quality of Shredded Iceberg Lettuce during Storage

The effect of basil leaf (BLE) and wheat bran (WBE) extracts (potent anti-browning agents), on the phenolic content, antioxidant potential, microbiological quality, and consumer quality of shredded lettuce during storage were studied. Treatment of lettuce with increasing concentrations of BLE proportionally increased the total phenolic content and antioxidant properties. Compared to the control, the treatment enhanced the antiradical properties. This was especially visible during the analysis of the chemical extracts, while this effect was not retained in the potentially bioaccessible fraction. In the lettuce stored for 8 days, the highest reducing potential and ability to quench radicals were observed in samples treated with 1% BLE-33 mg Trolox equivalent/g d.m. and 2.8 mg Trolox equivalent/g d.m., respectively. Compounds exhibiting antiradical properties were easily bioaccessible in vitro. There was no negative effect of the treatments on the consumer quality. Most importantly, after 8 days of storage, lettuce treated with the studied extract, except 10% WBE, had higher microbiological quality. After 8-day storage, the coliforms count was reduced by 84% and 88% in samples treated with 0.5% BLE and 10% WBE, respectively. In conclusion, treatments of shredded lettuce with BLE and WBE maintain or even improve its quality during storage.

Corryocactus brevistylus (K. Schum. ex Vaupel) Britton & Rose (Cactaceae): Antioxidant, Gastroprotective Effects, and Metabolomic Profiling by Ultrahigh-Pressure Liquid Chromatography and Electrospray High Resolution Orbitrap Tandem Mass Spectrometry

Corryocactus brevistylus (K. Schum. ex Vaupel) Britton & Rose (Cactaceae) is a shrubby or often arborescent cactus popularly known as "sancayo" and produce an edible fruit known as "Sanky" which is consumed in Arequipa-Perú. The purpose of this study was to report the gastroprotective activity and relate this activity to the antioxidant capacity and presence of phenolic compounds for the first time. A metabolomic profiling based on Ultrahigh-pressure liquid chromatography and electrospray high resolution mass spectrometry, and the antioxidant activities (DPPH, ABTS, and FRAP), ascorbic acid content, total phenolics and flavonoids contents, and the mode of gastroprotective action of the Sanky fruit including the involvement of prostaglandins, nitric oxide, and sulfhydryl compounds is reported. Thirty-eight compounds were detected in the ethanolic extract including 12 organic acids, nine hydroxycinnamic acids, three isoamericanol derivatives, six flavonoids, five fatty acids, and two sterols. The results of the biological tests showed that the ethanolic extract had antioxidant capacity and gastroprotective activity on the model of HCl/EtOH-induced gastric lesions in mice (at 10, 25, 50, and 100 mg/kg). The effect elicited by the extract at 50 mg/kg was reversed by indometacin and N-ethylmaleimide but not by N^G-nitro-L-arginine methyl ester suggesting that sulfhydryl groups and prostaglandins are involved in the mode of gastroprotective action. In conclusion, our study proves that C. brevistylus pears have some gastroprotective and antioxidant capacities and consumption is recommended for the presence of several bioactive compounds.

Phenolic content and potential bioactivity of apple juice as affected by thermal and ultrasound pasteurization

Thermal (T) and ultrasound (US) pasteurization processes were applied to apple juice and the phenolic compounds (TPC) were quantified before and after in vitro digestion by HPLC-DAD-ESI-MSⁿ, with their bioaccessibility ascertained. Digested samples were analysed for their inhibitory capacity against α-glucosidase. Since some of the compounds exhibit fluorescence, both steady state and time-resolved fluorescence methods were used to investigate the binding to a blood transport protein, human serum albumin (HSA). It was found that processing induced an increase in the TPC content, which was more pronounced when US was applied. In contrast, digestion reduced the TPC content, evening out the overall effect. Still T and US pasteurized juices exhibited a higher quantity of TPC upon digestion as compared to the raw sample. No correlation was found between the TPC content and α-glucosidase inhibition, as the T and US pasteurized juices showed the highest and lowest inhibitory capacities against the enzyme, respectively. This is indicative that other compounds, such as those formed upon thermal treatment, may be involved in the antidiabetic effect of apple juice. The fluorescence study showed that binding occurred to HSA, at slightly different rates for different species present in the US treated extract. Considering energy consumption, US pasteurization is the most power consuming treatment despite its shorter duration. Overall, no univocal indication on the best pasteurization process can be gathered. Thus, it is necessary to define the desired target in order to drive technological interventions by a customized approach.

Effect of milk addition and processing on the antioxidant capacity and phenolic bioaccessibility of coffee by using an in vitro gastrointestinal digestion model

An in vitro gastrointestinal digestion model was used to investigate the effects of milk matrix: skimmed milk (Sm), whole milk (Wm) and processing methods: pH adjustment, high pressure homogenization processing (HPHP), thermal treatment (TT) on the antioxidant capacity, phenolics bioaccessibility of coffee. Our findings showed that the antioxidant capacity of all the samples decreased or unchanged after in vitro digestion. The total phenolic bioaccessibility of coffee (C), coffee with whole milk (Cwm), and coffee with skimmed milk (Csm) decreased by 29.2%, 28.5%, 21.1% from the HPHP treatment and by 14.7%, 34.2%, and 33.8% from TT, respectively. pH adjustment had little effect on the total phenolic bioaccessibility of Cwm and Csm but significantly decreased that of C. Wm showed better protective effect on the phenolic bioaccessibility than Sm. These results may contribute to the optimization of formulations and processing methods in coffee beverage production, thereby increasing the health benefits of coffee.

Pulp in Shop-Bought Orange Juice Has Little Effect on Flavonoid Content and Gut Bacterial Flavanone Degradation In Vitro

Orange juice is an important source of flavanones in the Western diet. However, little is known of the variation in flavanone content of shop-bought orange juice with pulp (OJP) or without pulp (OJ), nor the impact of pulp on the fate of flavanones in the gut. Total phenols, total flavonoids, antioxidant capacity, hesperidin and narirutin, and dietary fibre were measured in six orange juice brands sold as OJP and OJ. The inclusion of pulp had little impact on fibre content. Apart from total phenols (OJ: 208.4 ± 10.7 μg gallic acid equivalents (GAE) ml^-1; OJP: 225.9 ± 16.7 μg GAE ml^-1, P < 0.05), there were no differences between OJ and OJP. The fate of flavanones in OJ and OJP (Tropicana) were further compared using in vitro gastrointestinal (GI) models. After in vitro upper GI digestion, recovery of hesperidin was higher in OJ compared with OJP (89 ± 6 vs. 68 ± 3%, P = 0.033). After 2 h colonic fermentation, hesperidin was 1.2 fold higher in OJP than OJ. However, after 24 h colonic fermentation there was no significant difference between juices in terms of hesperidin, hesperetin, narirutin, naringenin and catabolites. In conclusion, the amount of pulp included in these shop-bought orange juices had little impact on flavanone metabolism in models of the GI tract. The effects of greater amounts of orange pulp remain to be determined.

RESEARCH OF QUALITY AND COMPETITIVENESS OF TOMATO JUICES

The paper considers the results of the complex quality estimation and competitiveness determination of tomato juices of different producers, exported in European countries. The complex estimation of tomato juices quality was realized according to the results of studying organoleptic (color, taste, smell, consistence) and physical-chemical (content of dry substances, β-carotene, flesh, mass share of titrated acids) parameters of 4 samples. According to the results of the complex qualimetric estimation, the highest value of the integral quality parameter was reached by tomato juice of ТМ «Galiciа» (Ukraine) (0,86). The lowest value of this parameter was established for experimental samples of tomato juices of ТМ «Rich» (Ukraine) (0,65) and ТМ «Sandora» (Ukraine) (0,61). The lower value of the integral quality parameter was inherent to juice of TM «Sadochok» (Ukraine) (0,40), explained, first of all, by insufficiently saturated and homogenous red color with inclusions, watery and liquid consistence, content of side admixtures, signs of stratification. The competitiveness of tomato juices was estimated, taking into account functional, esthetical and economic quality parameters. The basic commodity was determined as tomato juice of ТМ «Galiciа» by the results of the complex quality estimation. According to the obtained results, tomato juice of ТМ «Rich» was found competitive by the ratio of functional, esthetical and economic parameters (1,19) that is conditioned by high esthetical and functional indices and also moderate price of realization. The relatively high (but less one unit) competitiveness level was inherent to juice of ТМ «Sandora» (0,97) by the expanse of a high realization price at rather high esthetical and functional indices. It has been determined, that juice of ТМ «Sadochok» is least competitive because of worst esthetical indices, despite a low realization price. Thus, the main factor that influences the competitiveness of juices is a “price-quality” ratio. The obtained research results of the tomato juices quality and the used methodology of their competitiveness estimation may be useful for retail representatives (categorical managers) for the effective realization of products under conditions of competitiveness.

Biological activity and chemical characterization of Pouteria lucuma seeds: A possible use of an agricultural waste

Pouteria lucuma fruit is widely used to prepare cakes, ice creams and juice or also commercialized as pulp and flour. As result of this business thousands of tons of seeds are generated as an agricultural waste. This study presents the antioxidant and antiulcer activities, and the identification of secondary metabolites by UHPLC/ESI/MS/MS of an agroindustrial waste of Pouteria lucuma seeds. Fifty-nine compounds were tentatively identified including eight aminoacids, five organic acids, one nucleoside, five phenolic acids, five phenolic alcohols, nineteen flavonoids, six lipids, and seven unknowns in the methanol extract of P. lucuma seeds. The total phenolic content of the seeds was 52.82 ± 0.09 μmol GAE/g dry weight, while total flavonoid content was 5.99 ± 0.01 μmol Q/g dry weight. The antioxidant activity was 58.14 ± 0.05, 66.97 ± 0.00, 272.50 ± 0.00, and 67.02 ± 2.23 for the DPPH, ABTS, FRAP, and superoxide anion assays, respectively. The highest gastroprotective activity was obtained at 100 mg/kg (78%), which as higher than the positive control lansoprazole (75%). Our findings showed that P. lucuma seed extracts have moderate to high antioxidant activity and gastroprotective properties. Therefore, it was demostrated that lucuma seeds commonly eliminated as an agricultural industry waste, could be useful for the preparation of nutritional supplements.

Monkey orange fruit juice improves the nutritional quality of a maize-based diet

This paper studied the nutritional impact of the use of juice from Strychnos cocculoides (monkey orange) in a maize-based porridge. Monkey orange juice is traditionally used to supplement maize porridge - a staple breakfast cereal especially for vulnerable groups. Monkey orange fruits contain high amounts of micronutrients and phenolic compounds and are widely distributed throughout sub-Saharan Africa. The valuable components can be efficiently extracted by traditional and pectinase maceration techniques. The bioaccessibility of minerals and main phenolic compounds in maize porridge (5 g maize meal) supplemented by monkey orange juice (100 ml) were assessed after in-vitro digestion together with the kinetics of starch degradation. Caffeic and protocatechuic acids exceeded 100%, and chlorogenic acid 81% bioaccessibility after simulated intestinal digestion. Rutin was undetected after the simulated intestinal phase due to precipitation in the pellet. In-vitro bioaccessibility of minerals ranged from 12 to 62% in monkey orange enriched porridge. A 50-70% decrease of starch hydrolysis was observed at the end of the simulated intestinal digestion of monkey orange maize porridge confirming the known potential of phenolic compounds to decrease the glycaemic index of starch-rich foods. Consequently monkey orange juice appeared a suitable ingredient to enrich staple maize porridge thanks to its micronutrients and health benefit potential. Similar relationships of other fruits and starchy foods warrant study as a means to improve the nutritional quality of the diets of malnourished populations.