The Digestibility of Hibiscus sabdariffa L. Polyphenols Using an In Vitro Human Digestion Model and Evaluation of Their Antimicrobial Activity.

Hibiscus sabdariffa L. (H.s.) is a polyphenolic-rich plant commonly consumed either as a beverage or spice. The aim of the present study was to evaluate the in vitro digestibility of H.s. polyphenols using an in vitro model of digestion which simulates the human stomach and small intestine. The bioaccessible polyphenols released in the digested samples were analyzed by liquid chromatography coupled to photodiode array and mass spectrometry detection. H.s. anthocyanins (cyanidin-3-O-sambubioside and delphinidin-3-O-sambubioside) content drastically dropped during the digestion process from 2.91 ± 0.03 µg g-1 and 8.53 ± 0.08 µg g-1 (w/w) CG (Cyanidin-glucoside) in the raw extract, respectively, to 0.12 ± 0.01 µg g-1 0.12 ± 0.01 µg g-1 (w/w) CG at the end of duodenal digestion. Total polyphenols also have shown a decrease from 1192.65 ± 30.37 µg g-1 (w/w) in the raw extract to 282.24 ± 7.21 µg g-1 (w/w) by the end of gastric digestion, in contrast to their increase by the end of duodenal digestion 372.91 ± 3.97 µg g-1 (w/w). On the other hand, the decrease in certain compounds (e.g., caffeoylquinicandcoumaroylquinic acids) was observed during gastric digestion resulting in an increase of quinic acid in the duodenal aliquots, thus suggesting that this compound was derived from the degradation of the more complex hydroxycinnamic acids. H.s. extract also exhibited a bacteriostatic effect against Staphylococcus aureus ATCC 6538 (MIC of 2.5 mg mL-1) and a bactericidal effect against a food isolate of Listeria monocytogenes (MBC of 2.5 mg mL-1). The undigested polyphenols of H.s. in the upper gastrointestinal tract enters the colon, where they are metabolized by the gut microbiota. The present study results showed that resistance of H.s. polyphenols during gastrointestinal digestion might affect their uptake, resulting in a decrease in their digestibility.

Grape seed proanthocyanidin-loaded gel-like W/O/W emulsion stabilized by genipin-crosslinked alkaline soluble polysaccharides-whey protein isolate conjugates: Fabrication, stability, and in vitro digestion.

The present work aims to fabricate the genipin-crosslinked alkaline soluble polysaccharides-whey protein isolate conjugates (G-AWC) to stabilize W/O/W emulsions for encapsulation and delivery of grape seed proanthocyanidins (GSP). After crosslinking reaction, the molecular weight was increased and surface hydrophobicity was decreased. Then, the G-AWC and polyglycerol polyricinoleate (PGPR, a lipophilic emulsifier) were employed to prepare a GSP-loaded W/O/W emulsion with the addition of gelatin and sucrose in W1 phase via a two-step procedure. Creamed emulsion could be fabricated at W1/O volume fraction (Φ) of 10%-70% and further increased Φ to 75% or even up to 90% could obtain gel-like emulsion with notably elastic behaviors. In the W1/O/W2 emulsion with Φ of 80%, the encapsulation efficiency (EE) of GSP reached up to 95.86%, and decreased by ca. 10% after a week of storage. Moreover, the encapsulated GSP in the emulsion showed a remarkably higher bioaccessibility (40.72%) compared to free GSP (13.11%) in the simulated gastrointestinal digestion. These results indicated that G-AWC-stabilized W/O/W emulsions could be an effective carrier to encapsulate water-soluble bioactive compounds with enhanced stability and bioaccessibility.

Internal dose of vanadium in rats following repeated exposure to vanadyl sulfate and sodium orthovanadate via drinking water.

Vanadium is a ubiquitous environmental contaminant that exists in multiple oxidation states. Humans are exposed to vanadyl (V4+) and vanadate (V5+) from dietary supplements, food, and drinking water and hence there is a concern for adverse human health. The current investigation is aimed at identifying vanadium oxidation states in vitro and in vivo and internal concentrations following exposure of rats to vanadyl sulfate (V4+) or sodium metavanadate (V5+) via drinking water for 14 d. Investigations in simulated gastric and intestinal fluids showed that V4+ was stable in gastric fluid while V5+ was stable in intestinal fluid. Analysis of rodent plasma showed that the only vanadium present was V4+, regardless of the exposed compound suggesting conversion of V5+ to V4+ in vivo and/or instability of V5+ species in biological matrices. Plasma, blood, and liver concentrations of total vanadium, after normalizing for vanadium dose consumed, were higher in male and female rats following exposure to V5+ than to V4+. Following exposure to either V4+ or V5+, the total vanadium concentration in plasma was 2- to 3-fold higher than in blood suggesting plasma as a better matrix than blood for measuring vanadium in future work. Liver to blood ratios were 4-7 demonstrating significant tissue retention following exposure to both compounds. In conclusion, these data point to potential differences in absorption and disposition properties of V4+ and V5+ salts and may explain the higher sensitivity in rats following drinking water exposure to V5+ than V4+ and highlights the importance of internal dose determination in toxicology studies.

Preparation of nanofibrillated cellulose from grapefruit peel and its application as fat substitute in ice cream.

Grapefruit peel nanofibrillated cellulose (GNFC) was used as fat substitute in ice cream. GNFC was characterized by TEM, SEM, and XRD. The effects of GNFC on textural profiles, rheological properties, melting resistance, sensory properties, microstructure, and gross energy (GE) of ice cream were investigated. The results showed that GNFC was short rod-shaped crystal. Ice cream added with GNFC exhibited elastic-dominated behavior and better textural properties. The sensory evaluation score reached the highest level with desirable three-dimensional network structure at 0.4 % GNFC addition. GE of ice cream significantly decreased with reducing fat with maximal reduction rate of 17.90 %. Furthermore, the results of in vitro simulated digestion showed that GNFC addition and fat reduction significantly inhibited fat digestibility of ice cream due to coalescence of fat droplets on GNFC. This study provides new sustainable perspectives for the application of GNFC prepared from agricultural waste as fat substitute in food products.

Rheological Characteristics of Soluble Fibres during Chemically Simulated Digestion and their Suitability for Gastroparesis Patients.

Dietary fibres are an integral part of a balanced diet. Consumption of a high-fibre diet confers many physiological and metabolic benefits. However, fibre is generally avoided by individuals with gastrointestinal motility disorders like gastroparesis due to increased likelihood of exacerbated symptoms. Low-viscosity soluble fibres have been identified as a possible source of fibre tolerable for these individuals. The aim of this study is to determine the rheological properties of 10 common commercially available soluble fibres in chemically simulated digestive conditions and evaluate their suitability for individuals with mild to moderate gastroparesis, a gastric motility disorder. Rheological testing under neutral condition (distilled water pH 7) and chemically simulated gastric digestion were evaluated to determine the yield point and relative viscosity of each fibre. Our results reveal two rheological categories of soluble fibres; pseudoplastic and dilatant. Simulated digestion was shown to significantly alter the yield-points of psyllium husk, iota-carrageenan, beta-glucan, apple-fibre pectin, and inulin. Gum Arabic and partially hydrolysed guar gum showed the lowest viscosities and were not affected under simulated digestion, characteristics that make them potential candidate fibres for patients with gastroparesis. Altogether, our results demonstrate that digestion can have a significant impact on fibre viscosity and should be taken into consideration when evaluating the suitability of fibres for patients with gastric motility disorders.

Influence of oral administration mode on the efficacy of commercial bovine Lactoferrin against iron and inflammatory homeostasis disorders.

Milk derivative bovine Lactoferrin (bLf), a multifunctional glycoprotein available in large quantities and recognized as safe, possesses high homology and identical functions with human Lactoferrin. There are numerous food supplements containing bLf which, however, can vary in its purity, integrity and, consequently, functionality. Here, we report on a clinical trial where bLf (100 mg two times/day) was orally administered before (Arm A) or during meals (Arm B) to pregnant women with hereditary thrombophilia and suffering from anemia of inflammation. A significant increase of the number of red blood cells (RBCs), hemoglobin (Hb), total serum iron (TSI) and serum ferritin (sFtn) levels, along with a significant decrease of interleukin-6 were detected after 30 days in Arm A, but not in Arm B, thus letting us to hypothesize that bLf inefficacy could be related to its degradation by digestive proteases. To verify this hypothesis, bLf was incubated in gastric juice collected before or after meals. An undigested or a digested profile was observed when bLf was incubated in gastric juice sampled before or after meals, respectively. These results can explain the beneficial effect observed when bLf is administered under fasting conditions, i.e. in the absence of active proteases.

Structural changes in mulberry (Morus Microphylla. Buckl) and chokeberry (Aronia melanocarpa) anthocyanins during simulated in vitro human digestion.

Mulberry and chokeberry are rich sources of anthocyanins. In this study, the effect of the anthocyanin composition on the anthocyanin profile changes during in vitro digestion (mimicking the physiological conditions) was investigated by UHPLC-(ESI)-qTOF and UHPLC-(ESI)-QqQ. The antioxidant activity before and after in vitro digestion was elucidated. Cyanidin-3-O-glucoside and cyanidin-3-O-galactoside were dominant in mulberry and chokeberry, respectively. Moreover, the loss of cyanidin-3-O-galactoside in the chokeberry extract after digestion was greater than that of cyanidin-3-O-glucoside in the mulberry extract. After digestion, phenolic acids including protocatechuic acid and various cyanidin conjugates were newly formed because of decomposition and changes in the cyanidin-glycosides. The phenolic acid and cyanidin conjugate levels varied depending on the cyanidin glycoside sources in the colonic fraction. Finally, antioxidant activity before and after digestion was higher in the chokeberry extract than in the mulberry extract. Moreover, this activity continuously decreased until intestinal digestion but increased in the colonic fraction.

A New Food-grade Coenzyme Q10 Formulation Improves Bioavailability: Single and Repeated Pharmacokinetic Studies in Healthy Volunteers.

BACKGROUND: Coenzyme Q10 is a fundamental endogenous factor involved in cell energy production that shows protective properties in oxidative stress, mainly in skeletal and heart muscle. Coenzyme Q10 supplementation appears to benefit athletes in strenuous training and in the elderly, demonstrating ant-inflammatory properties by reducing inflammatory cytokines. Improved absorption of coenzyme Q10 via a new delivery system would represent an important step forward in the use of coenzyme Q10 as a dietary supplement. OBJECTIVE: The aim of the study was to evaluate the solubility and oral absorption in human healthy volunteers of a new food grade coenzyme Q10 phytosome formulation. METHODS: Solubility studies were performed in vitro in simulated gastrointestinal fluids; human studies were conducted in healthy volunteers to evaluate oral absorption in a Single dose study, in comparison with the coenzyme Q10 capsules, and in a repeated study at two increasing doses. RESULTS: The highest solubility shown by coenzyme Q10 phytosome in simulated intestinal fluids results in an improvement in oral absorption of coenzyme Q10 in healthy volunteers, three times more than the coenzyme Q10 according to AUC (area under the time/concentration curve) values. When two increasing doses (one and two capsules) were administered to healthy volunteers within a two-week schedule, the plasmatic levels of coenzyme Q10 resulted in 0.864±0.200 µg/ml (Mean±S.D.+41%) and 1.321±0.400 µg/ml (+116%), respectively versus baseline (0.614±0.120 µg/ml one capsule, 0.614±0.160 µg/ml two capsules). This detected dose-related bioavailability of coenzyme Q10 phytosome was even observed with no alterations in vital signs, neither in the physical examination nor in ECG, and no changes of clinical and biochemical parameters were observed. CONCLUSION: These findings, taken together, support the safety profile and significantly improved coenzyme Q10 oral absorption in humans with this new phytosome delivery formulation.

Phytochemical profile, mineral content, and antioxidant activity of Olea europaea L. cv. Cornezuelo table olives. Influence of in vitro simulated gastrointestinal digestion.

The main goals of this study were to determine the phenolic composition and antioxidant activity of table olives from Olea europaea L. cv. Cornezuelo, as well as the effect caused by a simulated in vitro digestion to evaluate compounds bioavailability. High-performance liquid chromatography with diode-array and mass spectrometry detection (HPLC-DAD-MSn) was used to evaluate the phytochemical profile, whereas conventional spectrophotometric methods (ABTS·+ and DPPH) were used to determine the antioxidant activity. The mineral content was also quantified by inductively coupled plasma - mass spectrometry. Thirty compounds were identified, mainly polyphenols, quantifying the major compounds by HPLC-DAD. After the simulated digestion, the phenolic content suffered an important decrease - more than 50% - reaching losses of up to 75% for oleuropein and comselogoside isomers. This decrease also resulted in a loss of antioxidant activity, observing significant differences for all parameters. However, the analyzed extracts still retained considerable antioxidant potential.

Action of euptox A from Ageratina adenophora juice on human cell lines: A top-down study using FTIR spectroscopy and protein profiling.

Euptox A, from Ageratina adenophora juice, is a toxin associated with the plant's resistance to infections, invasiveness and traditional use in cancer treatment. We used FTIR spectroscopy and protein profiling of cell lines to study the impact of euptox A on human cells, to clarify its mechanism of action in a top-down approach. Euptox A was extracted from the juice of A. adenophora. Its stability in the gastrointestinal tract was evaluated, as the compound/juice is generally taken orally. Cytotoxicity was determined in HeLa, Caco-2 and MCF7 cells, and the mechanism of action analyzed by protein and metabolite profiles using electrophoresis and FTIR spectroscopy. Euptox A resisted gastrointestinal digestion and was the most cytotoxic component of the extract for all cell lines tests. Euptox A-treated HeLa cells showed changes in protein profile, especially on 40S ribosomal protein S8 (RP), generally associated with cancer cells. FTIR profiles of treated cells diverged in the same metabolites as cells treated with cisplatin, both in metabolite directed analysis and in multivariate analysis (principal component analysis). In conclusion, euptox A in this top-down study showed a cellular impact that suggests a strong potential against cancer, acting on cancer targeted cellular characteristics.

Encapsulated drug system based on the gels obtained from callus cultures modified pectins.

The aims of this research were to obtain modified pectins of callus cultures using various culture conditions, to evaluate the relationship between the chemical characteristics of pectins, the swelling behavior and the release of prednisolone from calcium pectinate gel (CaPG) beads. An increase of the calcium concentration in the culture media correlated significantly with the rhamnogalacturonan I (RG-I) branching of the pectin. The beads from the pectin with a higher RG-I branching had the lower prednisolone release in a gastric fluid. The beads produced from the pectins obtained from callus cultured with a higher calcium concentration showed the lower prednisolone release. The swelling of the CaPG beads from pectin with a lower molecular weight (Mw) or linearity occurred to a lower degree. All beads prepared from modified pectins showed a high stability and a slow liberation of prednisolone in the simulated gastric and intestinal fluids, whereas rapid drug release in a colonic fluid. An applied strategy involving modification of the pectic structure using the abiotic factors allows obtaining the pectic gels with modified functional properties, in particular, with enhanced gastric and small intestinal resistance and a low drug release. These CaPG beads can be applied as the carriers for colon delivery of the drugs.

Pollen grains as a novel microcarrier for oral delivery of proteins.

Oral delivery of proteins and peptides is a challenge due to their degradation in the stomach. To overcome this challenge, ragweed (Ambrosia elatior) pollen grains were engineered to serve as protective microcapsules. A matrix comprising of Eudragit L100-55, an enteric polymer was deposited on the inner surfaces of ragweed pollens to protect the encapsulated protein from gastric degradation and to achieve pH-dependent release in the intestine. The Eudragit L100-55 matrix was formed without use of organic solvents so that solvent-induced damage to protein molecules could be prevented. To demonstrate the concept, bovine serum albumin (BSA) a model protein was used. A matrix of Eudragit L100-55 embedded with BSA was prepared in ragweed pollens by optimizing their respective concentrations for maximizing BSA loading in the matrix. The ability of this optimized formulation to protect BSA in simulated gastric acid fluid was evaluated. Release studies in simulated gastric fluid (pH 1.2) showed minimal BSA release from the ragweed-Eudragit L100-55 formulation. Analysis of BSA retained in the formulation after its exposure to gastric fluid confirmed that the residual BSA had not denatured. Release studies in the simulated intestinal fluid (pH 6.8) showed that ragweed pollen offered additional controlled release mechanism within the first few hours of release by virtue of their solid wall. In conclusion, upon use of a protein-friendly solvent for Eudragit L100-55, proteins could be encapsulated in ragweed pollen without denaturing them, and the resulting formulation exhibited selective release of the proteins at intestinal pH suggesting that the ragweed pollen grain-based formulation could be promising for oral delivery of proteins.

Comparative study of the bioaccessibility of the colorless carotenoids phytoene and phytofluene in powders and pulps of tomato: microstructural analysis and effect of addition of sunflower oil.

The objective was to assess the potential bioavailability of phytoene (PT) and phytofluene (PTF) from tomato powders used as raw materials for supplements as compared to the pulp of a common tomato and a cherry tomato. PT and PTF are attracting much interest nowadays as they can provide health and cosmetic benefits. PT and PTF levels in the more concentrated powder were up to 1000 times higher than in the tomatoes. The bioaccessibility from the powders was lower as compared to the tomato fruits and increased markedly when sunflower oil was added. However, the best source of potentially absorbable PT and PTF (0.5 and 2 mg g-1 respectively) was by far the powder with higher levels of them. This result could be due to the higher carotenoid concentration in the powder, the reduction of the particle sizes, and the rupture of cell structures compared to the pulps.

Preparation and Characterization of Resveratrol Loaded Pectin/Alginate Blend Gastro-Resistant Microparticles.

BACKGROUND: The use of resveratrol as a dietary supplement is limited because it is easily oxidized and, after oral ingestion, it is metabolized into enterocytes and hepatocytes. Thus, new formulations are needed in order to improve its oral bioavailability. OBJECTIVE: The objective of this study was to develop and characterize a gastro-resistant formulation of resveratrol for oral administration as a dietary supplement. METHOD: Resveratrol was encapsulated in Eudragit-coated pectin-alginate microparticles. RESULTS: The microparticle size was about 1450 µm, with an encapsulation efficiency of 41.72% ± 1.92%. The dissolution assay conducted, as specified in the European Pharmacopoeia for delayed-release dosage forms, revealed that our microparticles were gastro-resistant, because the resveratrol percentage released from microparticles in acid medium was less than 10%. In addition, the high-performance liquid chromatographic (HPLC) method developed for resveratrol content quantification in the microparticles was validated according to International Council for Harmonisation (ICH) Q2 (R1) guidelines. Finally, the biological activity of resveratrol was investigated in 3T3-L1 mature adipocytes, concluding that the encapsulation process does not affect the activity of resveratrol. CONCLUSION: In summary, the gastro-resistant microparticles developed could represent a suitable method of including resveratrol in dietary supplements and in functional foods used in obesity therapy.

Effects of a homogeneous polysaccharide from Sijunzi decoction on human intestinal microbes and short chain fatty acids in vitro.

ETHNOPHARMACOLOGICAL RELEVANCE: Sijunzi decoction (SJZD) is a classic recipe in traditional Chinese medicine (TCM) to strengthen the spleen and replenish Qi. It is well known for treating disorders of gastrointestinal function manifested in poor appetite, reduced food intake and loose stools. Polysaccharide is the most abundant constituent and the major effective component in SJZD. AIM OF THE STUDY: The present study aimed to understand the immunomodulatory mechanism of S-3-1, a homogeneous polysaccharide purified from SJZD with immune-enhancement activity, by investigating its effects on human intestinal microbes and short chain fatty acids. MATERIALS AND METHODS: S-3-1 was incubated with simulated gastric juice, intestinal juice, and human fecal microflora independently and sequentially. The concentrations of total polysaccharide and reducing sugar were measured to identify the stability of independently and sequentially incubated S-3-1 in three in vitro fermentation models. Gas chromatograph (GC) analysis was used to measure the short chain fatty acid (SCFA) contents in human fecal samples. The human gut microbiota composition was measured by 16S rRNA gene Illumina MiSeq sequencing (V3-V4 region). RESULTS: S-3-1 was degraded in three in vitro fermentation models separately and sequentially. Both S-3-1 and incubated S-3-1 could regulate the abundances of Lactobacillus, Pediococcus, Streptococcus, Bacteroides, Enterococcus, Clostridium and Dorea in human intestinal microflora samples. Specifically, S-3-1 could only regulate the abundances of Paraprevotella and Oscillospira, while the influenced flora changed to Butyricimonas, Coprococcus, Dialister, Sutterella, Ruminococcus and Parabacteroides after sequential incubation of S-3-1. In contrast to S-3-1 showing no influence on the content of SCFA, incubated S-3-1 showed increased contents of acetic acid and total acid that were associated with its effects on the abundances of Enterococcus, Sutterella, Butyricimonas and Streptococcus. CONCLUSION: S-3-1 plays an immunomodulatory role by regulating the abundances of 9 intestinal bacteria genera. Incubated S-3-1 can regulate more bacteria genera, a total of 13 kinds, and can adjust the SCFA content to affect immunomodulation. Incubation with gastric and intestinal juices enhanced S-3-1's capability of modulating the intestinal flora composition and decreased the bacteria's need for a carbon source. This study could provide new insights for studies on the pharmacological mechanisms of polysaccharides in vitro.

Parameters affecting the exposure to furfuryl alcohol from coffee.

Recently, furfuryl alcohol (FFA) was labelled a human potential carcinogen (group 2B) by the International Agency for Research on Cancer. Its alimentary exposure is mostly from coffee since in any other foods the concentrations are significantly lower. The various storage conditions of roasted coffee, the different brewing techniques applied and the bioaccessibility after ingestion are potential parameters that might alter the exposure to FFA from coffee. An 8 weeks stability study at varying temperatures showed that FFA is stable in the ground coffee matrix. Moreover, different brewing techniques extracted different amounts of FFA and affected its final concentration. The evaluation of the relative exposure to four furans (FFA, 5-hydroxymethyl-furaldehyde, 2-furoic acid, and 5-hydroxymethyl-2-furoic acid) revealed that FFA amounts were at least 2-fold the amounts of other studied furans in the same brew. A 22-fold variation in the concentration of the four furans in brews prepared using different coffee grounds and brewing techniques could be observed. 90% of the four furans were extracted by the first 25-30% fraction of the filter brew. A significant decrease of FFA is observed after stressing with simulated gastric fluid. However, this decrease could not be reproduced when mimicking a regular coffee ingestion situation.

Pluronics modified liposomes for curcumin encapsulation: Sustained release, stability and bioaccessibility.

The present work evaluated the feasibility of different pluronics (F127, F87 and P85) utilized as modifiers to improve the stability and bioaccessibility of curcumin liposomes (cur-Lps). Pluronics modified curcumin liposomes (cur-pluronic-Lps) were prepared by thin film evaporation combined with dynamic high pressure microfluidization. The particle size and polydispersity index of cur-pluronic-Lps was significantly lower than cur-Lps. Fourier transform infrared spectroscopy analysis revealed that curcumin was loaded in liposomes successfully and X-ray diffraction suggested that curcumin in the liposomes was in an amorphous state. In vitro release studies demonstrated that 73.4%, 63.9%, 66.7% and 58.9% curcumin released from cur-Lps, cur-F127-Lps, cur-F87-Lps and cur-P85-Lps, respectively. Compared with cur-Lps, cur-pluronic-Lps showed a slower release rate and lower cumulative release percentage for curcumin. Non-Fickian transport was the main release mechanism for cur-Lps, cur-F127-Lps and cur-F87-Lps, and typically the first-order model fitted cur-P85-Lps release. Stability studies (exposure to solutions of different pH and heat treatment) indicated that pluronics modification could enhance their pH stability and thermal stability. In vitro simulated gastrointestinal tract studies suggested that pluronics modification could significantly improve the absorption of cur-Lps. Bioaccessibility of curcumin liposomes increased in the following order: cur-Lps < cur-F87-Lps < cur-P85-Lps < cur-F127-Lps. These results may guide the potential application of pluronics modified liposomes as carriers of curcumin in nutraceutical and functional foods.

Development of Colorectal-Targeted Dietary Supplement Tablets Containing Natural Purple Rice Bran Oil as a Colorectal Chemopreventive.

Colorectal cancer occurs due to various factors. The important risks are dietary lifestyle and inflammatory bowel diseases, such as Crohn’s disease and ulcerative colitis. It has been found that the inhibitory enzyme cyclooxygenase-2 (COX-2) in the colorectal region can potentially reduce the risk of colorectal cancer. The present study investigated rice bran oil from natural purple rice bran, which exhibits antioxidant and anti-inflammatory activity. This study aimed to evaluate the bioactive compound content of natural purple rice bran oil (NPRBO) derived from native Thai purple rice and the anti-inflammatory activity of NPRBO in colorectal cancer cells, and to develop a colorectal delivery platform in the form of film-coated tablets. NPRBO from the rice bran of five different Thai purple rice cultivars, namely Khao’ Gam Leum-Phua (KGLP), Khao’ Gam Boung (KGB), Khao’ Gam Thor (KGT), Khao’ Gam Pah E-Kaw (KGPEK), and Khao’ Niaw Dam (KND), were extracted using the supercritical carbon dioxide extraction technique. The amount of γ-oryzanol (ORY), tocotrienols, and tocopherols present in NPRBOs and the in vitro anti-inflammatory activity of NPRBO were investigated. The highest anti-inflammatory NPRBO was transformed into a dry and free-flowing powder by liquisolid techniques. Then, it was compressed into core tablets and coated with Eudragit®L100 and Eudragit® NE30D. The in vitro release study of the film-coated NPRBO tablets was performed in three-phase simulated gastrointestinal media. The cultivar KGLP was superior to the other samples in terms of the ORY, tocotrienol and tocopherol contents and anti-inflammatory activity. Aerosil® was the most suitable absorbent for transforming NPRBO into a free-flowing powder and was used to prepare the NPRBO core tablets. The in vitro KGLP-NPRBO film-coated tablet release profile showed that no ORY was released at gastric pH while 85% of ORY was released at pH 7.4 after 6 h; this would be expected to occur in the colorectal area. Therefore, this study demonstrates the potential of KGLP-NPRBO to prevent colorectal cancer via a specific colorectal dietary supplement delivery system.

Improving in vivo conversion of oleuropein into hydroxytyrosol by oral granules containing probiotic Lactobacillus plantarum 299v and an Olea europaea standardized extract.

This study reports novel food-grade granules for co-delivery of L. plantarum 299v and a standardized extract of Olea europaea leaves (Phenolea®) as oral carrier of probiotics and hydroxytyrosol. Different granule formulations containing either L. plantarum 299v (Lac), or the olive leave extract (Phe) or their combination (Lac-Phe) have been successfully produced through wet granulation employing excipients generally regarded as safe as granulating/binding agents. L. plantarum cells withstood the manufacturing process and were stable upon storage at 4 °C for more than 6 months. In vitro dissolution studies in simulated gastro-intestinal fluids showed the capability of the granules to rapidly dissolve and deliver both olive leave phenols and living L. plantarum cells. In simulated digestion conditions, Lac and Lac-Phe granules protected L. plantarum against the harsh environment of the gastro-intestinal tract. Co-administration of Lac and Phe oral granules to healthy mice provided for higher amounts of hydroxytyrosol in urines as compared to Phe granules alone, suggesting that L. plantarum 299v boosted in vivo conversion of oleuropein to hydroxytyrosol. On the other hand, PCR-assisted profiling of the Lactobacillus population in faeces obtained from mice treated with Lac or Lac plus Phe confirmed that the probiotic arrived alive to colon and was there able to exert a sort of perturbing effect on the climax colonic microflora. Overall, these results pave the way towards the development of a nutraceutical useful for combined delivery of bioactive hydroxytyrosol and probiotics to colon site.

Formulating orange oil-in-water beverage emulsions for effective delivery of bioactives: Improvements in chemical stability, antioxidant activity and gastrointestinal fate of lycopene using carrier oils.

The influence of carrier oil type on the chemical stability, antioxidant properties and bioaccessibility of lycopene in orange oil-in-water beverage emulsions was investigated. The emulsions were formulated with orange oil (A), which was partially (50%) replaced with tributyrin (B) or corn oil (C) because of their distinctively different fatty acid composition. The addition of corn oil enhanced the physical stability of the beverage during chilled storage by inhibiting Ostwald ripening. The formation of oxidation products was insignificant after storage for 28 days at 4 °C, regardless the type of added oil. Lycopene was more susceptible to chemical degradation in the presence of unsaturated, long chain triglycerides and the retention followed the order: A (87.94%), B (64.41%) and C (57.39%). Interestingly, bioaccessibility of lycopene was significantly lower for emulsions formulated with 50% corn oil as opposed to 100% orange oil as indicated by the simulated in vitro gastric digestion model.