In the present study, wheat water extractable arabinoxylans (WEAX) were isolated and characterized, and their capability to form covalently cross-linked films in presence of Debaryomyces hansenii was ...evaluated. WEAX presented an arabinose to xylose ratio of 0.60, a ferulic acid and diferulic acid content of 2.1 and 0.04 µg∙mg(-1) WEAX, respectively and a Fourier Transform Infra-Red (FT-IR) spectrum typical of WEAX. The intrinsic viscosity and viscosimetric molecular weight values for WEAX were 3.6 dL∙g(-1) and 440 kDa, respectively. The gelation of WEAX (1% w/v) with and without D. hansenii (1 × 10(7) CFU∙cm(-2)) was rheologically investigated by small amplitude oscillatory shear. The entrapment of D. hansenii decreased gel elasticity from 1.4 to 0.3 Pa, probably by affecting the physical interactions between WEAX chains. Covalently cross-linked WEAX films containing D. hansenii were prepared by casting. Scanning electron microscopy images show that WEAX films containing D. hansenii were porous and consisted of granular-like and fibre microstructures. Average tensile strength, elongation at break and Young's modulus values dropped when D. hansenii was present in the film. Covalently cross-lined WEAX containing D. hansenii could be a suitable as a functional entrapping film.
Currently, the high added-value compounds contained in plant by-products and wastes offer a wide spectrum of opportunities for their reuse and valorization, contributing to the circular economy. The ...bell pepper (Capsicum annum L.) is an exotic vegetable with high nutritional value that, after processing, leaves wastes (peel, seeds, and leaves) that represent desirable raw material for obtaining phytochemical compounds. This review summarizes and discusses the relevant information on the phytochemical profile of bell peppers and their related biological properties as an alternative to revalorize losses and wastes from bell peppers for their application in the food and pharmaceutical industries. Bell pepper fruits, seeds, and leaves contain bioactive compounds (phenols, flavonoids, carotenoids, tocopherol, and pectic polysaccharides) that exhibit antioxidant, antibacterial, antifungal, immunosuppressive and immunostimulant properties, and antidiabetic, antitumoral and neuroprotective activities, and have a potential use as functional food additives. In this context, the revalorization of food waste is positioned as a technological and innovative research area with beneficial effects for the population, the economy, and the environment. Further studies are required to guarantee the safety use of these compounds and to understand their mechanisms of action.
Microalgae are a group of microorganisms used in aquaculture. The number of studies regarding their use as a functional food has recently increased due to their nutritional and bioactive compounds ...such as polysaccharides, fatty acids, bioactive peptides, and pigments. Specific microalgal glucans (polysaccharides) can activate the immune system or exert antioxidant and hypocholesterolemic effects. The importance of algal lipids is based on their polyunsaturated fatty acids, their anti-inflammatory effects, their modulation of lipid pathways, and their neuroprotective action. Microalgae peptides can bind or inhibit specific receptors in cardiovascular diseases and cancer, while carotenoids can act as potent antioxidants. The beneficial biological activity will depend on the specific microalga and its chemical constituents. Therefore, knowledge of the composition of microalgae would aid in identifying, selecting, and studying their functional effects.
Acute hepatopancreatic necrosis disease (AHPND), caused by marine bacteria Vibrio Parahaemolyticus, is a huge problem in shrimp farms. The V. parahaemolyticus infecting material is contained in a ...plasmid which encodes for the lethal toxins PirABVp, whose primary target tissue is the hepatopancreas, causing sloughing of epithelial cells, necrosis, and massive hemocyte infiltration. To get a better understanding of the hepatopancreas response during AHPND, juvenile shrimp Litopenaeus vannamei were infected by immersion with V. parahaemolyticus. We performed transcriptomic mRNA sequencing of infected shrimp hepatopancreas, at 24 hours post-infection, to identify novel differentially expressed genes a total of 174,098 transcripts were examined of which 915 transcripts were found differentially expressed after comparative transcriptomic analysis: 442 up-regulated and 473 down-regulated transcripts. Gene Ontology term enrichment analysis for up-regulated transcripts includes metabolic process, regulation of programmed cell death, carbohydrate metabolic process, and biological adhesion, whereas for down-regulated transcripts include, microtubule-based process, cell activation, and chitin metabolic process. The analysis of protein- protein network between up and down-regulated genes indicates that the first gene interactions are connected to oxidation-processes and sarcomere organization. Additionally, protein-protein networks analysis identified 20-top highly connected hub nodes. Based on their immunological or metabolic function, ten candidate transcripts were selected to measure their mRNA relative expression levels in AHPND infected shrimp hepatopancreas by RT-qPCR. Our results indicate a close connection between the immune and metabolism systems during AHPND infection. Our RNA-Seq and RT-qPCR data provide the possible immunological and physiological scenario as well as the molecular pathways that take place in the shrimp hepatopancreas in response to an infectious disease.
The Almaco jack (
Seriola rivoliana
) is a marine fish maintained in mariculture systems and frequently infested by monogenean parasites like
Neobenedenia
sp. Severe infestations can lead to high ...mortalities and economic losses for farmers. This study evaluated the effects of temperature on the immune response on Almaco jack infested with
Neobenedenia
sp. We exposed infested fishes at temperatures of 20 °C, 24 °C, and 30 °C for 20 days and took samples of different tissues at the beginning of the experiment, and after 3 and 20 days. The tissues considered were the skin, thymus, cephalic kidney, and spleen to evaluate the relative gene expression of different genes: Hsp70, IgM, IL-1β, IL-10, and MyD88. Our results showed an increase in IL-1β gene expression in the skin after 20 days of infestation but no significant effect of temperature on gene expression, despite increases in infestation rates with temperature. Therefore, relative genetic expression was controlled by the number of parasites and the days post-infestation. These results show that the parasite infestation induced a local response in the skin, but that temperature has an indirect effect on the immune system of Almaco jack.
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•In vitro tests D. hansenii significant decreases the mycelial growth of four maize postharvest pathogens.•Presence of D. hansenii reduced the production of fumonisins of F. ...subglutinans in 59.8% in vivo.•First time that marine yeast is used to the mold control in maize grain.
Debaryomyces hansenii is an antagonistic yeast that has been shown high effectiveness against different phytopathogenic fungi in diverse habitats. Both, the antagonistic activity of D. hansenii BCS003 and its mechanism against four pathogenic fungi (Mucor circinelloides, Aspergillus sp., Fusarium proliferatum and Fusarium subglutinans) in maize grains (Zea mays L.) were evaluated. Results indicated an almost entirely decrease (97.2–98.3%) of mycelial growth in a radial inhibition assay against four strains of pathogenic fungi by the D. hansenii action. In diffusible and volatile compounds as well cell-free supernatants in vitro assays D. hansenii showed significant inhibitory activity (p<0.05) against Aspergillus sp., F. proliferatum and F. subglutinans. The four isolated fungi were used to infect maize grains and results showed a partial inhibition of the mycelial growth and a 24h delay in the disease appearance when compared to control (not D. hansenii treated maize grain). Moreover, the application of D. hansenii reduced the production of F. subglutinans fumonisins by 59.8% after seven days of co-incubation without affecting the chemical and mineral composition of maize grain. According to these results, D. hansenii BCS003 could be considered a potential biocontrol agent against toxigenic molds in maize grains, probably due to the synergistic effects of the factors such as the competition for nutrients and space, as well as the production of extracellular soluble and volatile compounds. The potential of marine D. hansenii as biocontrol agent merits further research to improve its efficacy.
Transient expression systems for plants have several advantages for the development of innovative plant-made vaccines. This technology has the potential to render veterinary vaccines against relevant ...diseases, such as paratuberculosis, a chronic intestinal infectious disease affecting livestock. This study showed that
Agrobacterium
-mediated transient transformation of maize seedlings allows the production of the Ag85B antigen from
Mycobacterium avium
subsp.
paratuberculosis
(MAP) at levels up to 11.35 µg g
−1
dry weight. Moreover, BALB/c mice orally and subcutaneously immunized with the maize-made Ag85B vaccine produced specific IgG and IgA antibodies. Therefore, this platform is proposed as a rapid approach to produce the functional MAPAg85B antigen at sufficient yields to induce specific humoral immune responses in animal testing, which constitutes the first step in the development of a plant-made oral vaccine against paratuberculosis.
Key message
This paper describes for the first time, the transient transformation of maize seedlings to produce Ag85B vaccine from
Mycobacterium avium
subsp.
paratuberculosis
. The plant-produced antigen showed strong immunoreactivity in immunized mice.
Programmed cell death (PCD) is an essential process for the immune system's development and homeostasis, enabling the remotion of infected or unnecessary cells. There are several PCD's types, ...depending on the molecular mechanisms, such as non-inflammatory or pro-inflammatory. Hemocytes are the main component of cellular immunity in bivalve mollusks. Numerous infectious microorganisms produce toxins that impair hemocytes functions, but there is little knowledge on the role of PCD in these cells. This study aims to evaluate
whether marine toxins induce a particular type of PCD in hemocytes of the bivalve mollusk
during 4 h at 25°C. Hemocytes were incubated with two types of marine toxins: non-proteinaceous toxins from microalgae (saxitoxin, STX; gonyautoxins 2 and 3, GTX2/3; okadaic acid/dynophysistoxin-1, OA/DTX-1; brevetoxins 2 and 3, PbTx-2,-3; brevetoxin 2, PbTx-2), and proteinaceous extracts from bacteria (
, Vp;
, Vc). Also, we used the apoptosis inducers, staurosporine (STP), and camptothecin (CPT). STP, CPT, STX, and GTX 2/3, provoked high hemocyte mortality characterized by apoptosis hallmarks such as phosphatidylserine translocation into the outer leaflet of the cell membrane, exacerbated chromatin condensation, DNA oligonucleosomal fragments, and variation in gene expression levels of apoptotic caspases 2, 3, 7, and 8. The mixture of PbTx-2,-3 also showed many apoptosis features; however, they did not show apoptotic DNA oligonucleosomal fragments. Likewise, PbTx-2, OA/DTX-1, and proteinaceous extracts from bacteria Vp, and Vc, induced a minor degree of cell death with high gene expression of the pro-inflammatory initiator caspase-1, which could indicate a process of pyroptosis-like PCD. Hemocytes could carry out both PCD types simultaneously. Therefore, marine toxins trigger PCD's signaling pathways in
hemocytes, depending on the toxin's nature, which appears to be highly conserved both structurally and functionally.
Synbiotics can prevent gastrointestinal infections in broilers. This work studies the effect of a Synbiotic on broilers. One-day-old male broilers were divided into groups: Control; Synbiotic; ...Synbiotic + S. Typhimurium; Synbiotic + C. perfringens; Synbiotic + S. Typhimurium + C. perfringens; S. Typhimurium; C. perfringens; and S. Typhimurium + C. perfringens. Histopathological analysis revealed that the Synbiotic promoted longer villi, less deep crypts, and better villi-crypt ratio. Broilers treated with the Synbiotic, infected with pathogens or not, had healthier mucosa. In groups infected with pathogens, the frequency and intensity of histopathologic lesions were lessened often in groups treated with the Synbiotic. The Synbiotic group had higher lactic acid bacteria counts than the Control group on day 39, and the isolation frequency of S. Typhimurium was lower (p < 0.05) in the Synbiotic-treated groups. On day 18, mucosa, villi, villi-crypt ratio, crypt, and feed intake were influenced by Enterobacteriaceae. However, on day 39 (end of the trial), those parameters were influenced by lactic acid bacteria. The Synbiotic influenced morphological modifications in the duodenal mucosa, which in turn gave the broilers the ability to resist infections caused by S. Typhimurium and C. perfringens, by inhibiting their growth and decreasing the intensity and frequency of histopathological injuries.
Immunogenicity of ToxA and Vibrio parahaemolyticus lysate was evaluated in a double immunostimulation scheme in Pacific red snapper after V. parahaemolyticus infection. Three groups of Pacific red ...snapper were intraperitonealy (i.p.) injected with phosphate-buffered saline (PBS group), ToxA of V. parahaemolyticus (ToxA-Vp group) or V. parahaemolyticus lysate (lysate-Vp group) (first injection, day 1; second injection, day 7). Fish were subsequently infected with live V. parahaemolyticus. Humoral immune parameters in skin mucus and serum were evaluated on days 1, 7, 8 and 14 days post-immunostimulation and 7 days post-infection. Moreover expression of immune-related genes was quantified by real time PCR in head-kidney leukocytes, spleen, liver, and intestine. The ToxA-Vp-treated group showed a higher anti-protease and catalase activity in skin mucus when compared with the PBS group. Measurements of SOD and CAT activities showed an increment in both activities a day after the second boost with ToxA-Vp or lysate-Vp. Interestingly, IgM levels in mucus and transcripts were enhanced followed the ToxA-Vp treatment even after challenge. Furthermore, IL-1β was strongly expressed in all analyzed cell or tissues followed ToxA-Vp or Vp-lysate treatments. Finally, SOD and CAT gene expression was up-regulated in fish immunostimulated with either treatment ToxA-Vp or lysate-Vp, mainly after infection in head-kidney leukocytes and intestine. This is the first study where the effects of ToxA from V. parahaemolyticus in the immune system of Pacific red snapper was evaluated. These results suggest that ToxA-Vp would positively affect humoral immune response and up-regulate expression of genes involved in the immune system function; and could help in the control of V. parahaemolyticus infection in Pacific red snapper Lutjanus peru, an economic important fish in Mexico.
•Immunogenicity and safety of recombinant ToxA was evaluated.•ToxA increase IgM levels in mucus and transcript IgM gene expression.•ToxA and Vibrio parahaemolyticus lysate increase humoral immune response in serum.•ToxA and Vp-lysate increased antioxidant and proinflammatory IL-1β gene expression.•ToxA used as immunostimulant could help in the control of V. parahaemolyticus infection.
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