Immunological and functional properties of the exudate gum from northwestern Mexican mesquite (Prosopis spp.) in comparison with gum arabic

©. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This document is the Published/Accepted/Submitted Manuscript version of a Published Work that appeared in final form in [International Journal of Biological Macromolecules]. To access the final edited and published work see [https://doi.org/10.1016/S0141-8130(97)00037-8]A comparison between the fine structural features of exudate gum from mesquite (Prosopis spp.) indigenous to NW Mexico and commercial gum arabic from Acacia spp. was achieved by means of immunological techniques. Their functional properties were compared from the ability to form oil-in-water emulsions and encapsulate cold press orange peel essential oil by spray drying. Fine comparison of the antigenic compounds in both materials against polyclonal rabbit antibodies, showed that the carbohydrate-rich components with slow mobility of mesquite gum are closely related to the faster ones of gum arabic. Also, close identity was observed for the components in the proteic fraction of both gums. Similar tannin concentrations were found in both materials (:0.43%) with only dark coloured samples bearing higher amounts (:1.9%). Gum arabic retained nearly 100% of the quantity of orange peel essential oil emulsified in water before spray drying, while mesquite gum did so for 90.6% of the citrus oil. From these results it is believed that mesquite gum might be a suitable replacement of gum arabic in arid regions of the world were Prosopis trees have widespread occurrence

Antimicrobial, cytotoxicity and preliminary phytochemical determination of commonly used medicinal plants to treat oral cavity, urinary tract and gut infections by inhabitants of Borabu sub-county, Nyamira County, Kenya

Aims: The study aimed at determining the antimicrobial activities and cytotoxicity properties of medicinal plants collected from southwestern Kenya. Methods and results: A total of 23 ethanol extracts of selected medicinal plants were bio-assayed against Gram-negative bacterial strains (Escherichia coli NU14, Helicobacter pylori ATCC 700824, and Porphyromonas gingivalis ATCC 33277). Cytotoxicity tests were also carried out on mammalian cell lines (AGS, KB, and TR146). Preliminary type of phytochemical compounds present in the extracts was determined by thin-layer chromatography. Cassia didymobotrya plant extract (1 mg/mL) had strong antimicrobial activity against P. gingivalis (average zone of inhibition of 21.70 ± 0.88 mm, MIC 0.13 ± 0.00 mg/mL and MBC 0.50 ± 0.00 mg/mL). E. coli was resistant to all the extracts bioassayed. Leonotis nepetifolia (15.80 ± 0.20 mm) and Clerodendrum myriacoides (14.20 ± 0.44 mm) showed only moderate activity against H. pylori. Cell cytotoxicity results indicated a dose-dependent response against KB, TR146 and AGS cell lines with C. didymobotrya having IC50 values of 47.64 and 704.00 µg/mL on KB and TR146 cell lines, respectively. L. nepetifolia and C. myriacoides did produce IC50 of 0.1883 mg/mL and 0.1061 mg/mL against the AGS cell line respectively. Conclusion, significance and impact of the study: Most of the extracts had no or weak activity against test isolates, but C. didymobotrya leaves extracts showed strong activity against P. gingivalis. C. didymobotrya can offer alternative medicare to P. gingivalis conditions

Current state of insect proteins: extraction technologies, bioactive peptides and allergenicity of edible insect proteins.

This review aims to provide an updated overview of edible insect proteins and the bioactivity of insect-derived peptides. The essential amino acid content of edible insects is compared with well-known protein sources to demonstrate that edible insects have the potential to cover the protein quality requirements for different groups of the population. Then the current methodologies for insect protein extraction are summarized including a comparison of the protein extraction yield and the final protein content of the resulting products for each method. Furthermore, in order to improve our understanding of insect proteins, their functional properties (such as solubility, foaming capacity, emulsifying, gelation, water holding capacity and oil holding capacity) are discussed. Bioactive peptides can be released according to various enzymatic hydrolysis protocols. In this context, the bioactive properties of insect peptides (antihypertensive, antidiabetic, antioxidant and anti-inflammatory properties) have been discussed. However, the allergens present in insect proteins are still a major concern and an unsolved issue for insect-based product consumption; thus, an analysis of cross reactivity and the different methods available to reduce allergenicity are proposed. Diverse studies of insect protein hydrolysates/peptides have been ultimately promoting the utilization of insect proteins for future perspectives and the emerging processing technologies to enhance the wider utilization of insect proteins for different purposes

Self-assembled high molecular weight inulin nanoparticles: Enzymatic synthesis, physicochemical and biological properties

Inulin has interesting physicochemical and functional properties, and therefore a wide range of applications in the food and medical industries. It has gained great traction due to its ability to form nanoparticles and its possible application as nanovehicle for drug delivery. In this work, we demonstrated that the enzymatically-synthesized high molecular weight (HMW) inulin forms stable spherical nanoparticles with an average diameter of 112 ± 5 nm. The self-assemblage of HMW inulin nanoparticles is carried out during enzymatic synthesis of the polymer, and become detectable after a certain critical aggregation concentration (CAC) is reached. Both, the CAC and nanoparticle size are influenced by the reaction temperature. These nanoparticles are not toxic for peripheral blood mononuclear cells, at concentrations below 200 μg/mL; no significant prebiotic potential was detected in cultures of 13 probiotic strains. This work contributes to a better understanding of the formation of HMW inulin nanoparticles and their biological properties

Co-Microencapsulation of Cushuro (Nostoc sphaericum) Polysaccharide with Sacha Inchi Oil (Plukenetia huayllabambana) and Natural Antioxidant Extracts

Cushuro (Nostoc sphaericum) polysaccharide was used to co-microencapsulate sacha inchi oil, natural antioxidant extracts from the oleoresin of charapita chili peppers (Capsicum frutescens L.) and grape orujo (Vitis vinifera L.). Encapsulation efficiency, moisture, particle size, morphology, oxidative stability, shelf-life, solubility, essential fatty acid profile, sterol content and antioxidant capacity were evaluated. The formulations with grape orujo extract showed higher oxidative stability (4908 ± 184 h), antioxidant capacity (4835.33 ± 40.02 µg Trolox/g ms), higher phenolic contents (960.11 ± 53.59 µg AGE/g ms) and a smaller particle size (7.55 µm) than the other formulations, as well as good solubility and a low moisture content. Therefore, grape orujo extracts can be used as natural antioxidants. The fatty acid composition (ω-3) remained quite stable in all the formulations carried out, which also occurred for sterols and tocopherols. In combination with gum arabic, grape orujo extract offered oxidative protection to sacha inchi oil during the first week of storage

Elaboration of a teaching program in development cooperation in the University of Alcalá

COOPUAH, a group of teachers and researchers of the University of Alcalá (UAH), who belong to different disciplines, consider that the training offered to students in Development Cooperation by their institution has some deficiencies. The group pursues the general objective of reflecting about and evaluating in particular how this field is included in the university curricula in order to propose a teaching program that could fill the that gap. The main results highlight that the current teaching offer is insufficient, it comes from the environmental and health sciences fields, and in organizational level, is concentrated in the 2nd semester. We therefore believe that we need a multidisciplinary work to expand this teaching offer, redistribute it both semesters, and to offer a program addressed to all students of the University of Alcalá and recognized officially by the institutio

In Vitro and Sensory Evaluation of Capsaicin-Loaded Nanoformulations

Capsaicin has known health beneficial and therapeutic properties. It is also able to enhance the permeability of drugs across epithelial tissues. Unfortunately, due to its pungency the oral administration of capsaicin is limited. To this end, we assessed the effect of nanoencapsulation of capsaicin, under the hypothesis that this would reduce its pungency. Core-shell nanocapsules with an oily core and stabilized with phospholipids were used. This system was used with or without chitosan coating. In this work, we investigated the in vitro release behavior of capsaicin-loaded formulations in different physiological media (including simulated saliva fluid). We also evaluated the influence of encapsulation of capsaicin on the cell viability of buccal cells (TR146). To study the changes in pungency after encapsulation we carried out a sensory analysis with a trained panel of 24 students. The in vitro release study showed that the systems discharged capsaicin slowly in a monotonic manner and that the chitosan coating had an effect on the release profile. The cytotoxic response of TR146 cells to capsaicin at a concentration of 500 μM, which was evident for the free compound, was reduced following its encapsulation. The sensory study revealed that a chitosan coating results in a lower threshold of perception of the formulation. The nanoencapsulation of capsaicin resulted in attenuation of the sensation of pungency significantly. However, the presence of a chitosan shell around the nanoformulations did not mask the pungency, when compared with uncoated systems

Nanoencapsulated capsaicin changes migration behavior and morphology of madin darby canine kidney cell monolayers

We have developed a drug delivery nanosystem based on chitosan and capsaicin. Both substances have a wide range of biological activities. We investigated the nanosystem’s influence on migration and morphology of Madin Darby canine kidney (MDCK-C7) epithelial cells in comparison to the capsaicin-free nanoformulation, free capsaicin, and control cells. For minimally-invasive quantification of cell migration, we applied label-free digital holographic microscopy (DHM) and single-cell tracking. Moreover, quantitative DHM phase images were used as novel stain-free assay to quantify the temporal course of global cellular morphology changes in confluent cell layers. Cytoskeleton alterations and tight junction protein redistributions were complementary analyzed by fluorescence microscopy. Calcium influx measurements were conducted to characterize the influence of the nanoformulations and capsaicin on ion channel activities. We found that both, capsaicin-loaded and unloaded chitosan nanocapsules, and also free capsaicin, have a significant impact on directed cell migration and cellular motility. Increase of velocity and directionality of cell migration correlates with changes in the cell layer surface roughness, tight junction integrity and cytoskeleton alterations. Calcium influx into cells occurred only after nanoformulation treatment but not upon addition of free capsaicin. Our results pave the way for further studies on the biological significance of these findings and potential biomedical applications, e.g. as drug and gene carriers

Chitosan encapsulation modulates the effect of capsaicin on the tight junctions of MDCK cells

Capsaicin has known pharmacological effects including the ability to reversibly open cellular tight junctions, among others. The aim of this study was to develop a strategy to enhance the paracellular transport of a substance with low permeability (FITC-dextran) across an epithelial cell monolayer via reversible opening of cellular tight junctions using a nanosystem comprised by capsaicin and of chitosan. We compared the biophysical properties of free capsaicin and capsaicin-loaded chitosan nanocapsules, including their cytotoxicity towards epithelial MDCK-C7 cells and their effect on the integrity of tight junctions, membrane permeability and cellular uptake. The cytotoxic response of MDCK-C7 cells to capsaicin at a concentration of 500 μM, which was evident for the free compound, is not observable following its encapsulation. The interaction between nanocapsules and the tight junctions of MDCK-C7 cells was investigated by impedance spectroscopy, digital holographic microscopy and structured illumination fluorescence microscopy. The nanocapsules modulated the interaction between capsaicin and tight junctions as shown by the different time profile of trans-epithelial electrical resistance and the enhanced permeability of monolayers incubated with FITC-dextran. Structured illumination fluorescence microscopy showed that the nanocapsules were internalized by MDCK-C7 cells. The capsaicin-loaded nanocapsules could be further developed as drug nanocarriers with enhanced epithelial permeability

Design of bio-nanosystems for oral delivery of functional compounds

Nanotechnology has been referred to as one of the most interesting topics in food technology due to the potentialities of its use by food industry. This calls for studying the behavior of nanosystems as carriers of biological and functional compounds aiming at their utilization for delivery, controlled release and protection of such compounds during food processing and oral ingestion. This review highlights the principles of design and production of bio-nanosystems for oral delivery and their behavior within the human gastrointestinal (GI) tract, while providing an insight into the application of reverse engineering approach to the design of those bio-nanosystems. Nanocapsules, nanohydrogels, lipid-based and multilayer nanosystems are discussed (in terms of their main ingredients, production techniques, predominant forces and properties) and some examples of possible food applications are given. Phenomena occurring in in vitro digestion models are presented, mainly using examples related to the utilization of lipid-based nanosystems and their physicochemical behavior throughout the GI tract. Furthermore, it is shown how a reverse engineering approach, through two main steps, can be used to design bio-nanosystems for food applications, and finally a last section is presented to discuss future trends and consumer perception on food nanotechnology.Miguel A. Cerqueira, Ana C. Pinheiro, Helder D. Silva, Philippe E. Ramos, Ana I. Bourbon, Oscar L. Ramos (SFRH/BPD/72753/2010, SFRH/BD/48120/2008, SFRH/BD/81288/2011, SFRH/BD/80800/2011, SFRH/BD/73178/2010 and SFRH/BPD/80766/2011, respectively) are the recipients of a fellowship from the Fundacao para a Ciencia e Tecnologia (FCT, POPH-QREN and FSE Portugal). Maria L. Flores-Lopez thanks Mexican Science and Technology Council (CONACYT, Mexico) for PhD fellowship support (CONACYT Grant number: 215499/310847). The support of EU Cost Actions FA0904 and FA1001 is gratefully acknowledged