•Polysaccharides have been extracted from the seeds of Lupinus luteus (yellow lupin).•Yellow lupin polysaccharides displayed a range of biological activities.•Lupin polysaccharides have potential for ...functional/nutraceutical applications.•Structural characterisation carried out by FT-IR and NMR.
Yellow lupin polysaccharides (YLP-1, YLP-2 and YLP-3) were isolated from the whole seeds of Lupinus luteus L. Their antioxidant activities were evaluated by ABTS+ and hydroxyl radical scavenging, and Fe2+ chelating assays. Immunostimulatory activities were measured by their ability to activate macrophages to produce TNF-α and NO. Four strains of probiotic bacteria were used to measure their prebiotic activities. YLP-2 with largest galactose content displayed the best activity amongst the three isolated polysaccharides. NMR and FT-IR spectroscopic methods have revealed that YLPs contain galactans and galactomannans which are linked with β-(1,4) glycosidic bond in the main chain. The side chain Galp unit of galactomannan is connected to the main chain Manp by α-(1,6) linkage. The results presented in this paper strongly suggest that YLPs display significant antioxidant, immunostimulatory and prebiotic activities and hence hold great potential as nutraceutical and functional agents.
Lupin is a major rotational crop produced abundantly in Australia. Three varieties of sweet lupins are grown in Australia depending on soil types and climatic conditions; these are white lupin ...(Lupinus albus), blue lupin (Lupinus angustifolius), and yellow lupin (Lupinus luteus). In this study, polysaccharides from the three lupin species have been extracted with hot water and a range of their biological activities investigated. The antioxidant activities of lupin polysaccharides have been measured in terms of ABTS
*+
radical and hydroxyl radical scavenging activities, and their affinity to chelate with iron. Immune-enhancing power of the lupin polysaccharides was examined by measuring their capacity to stimulate the macrophages (RAW 264.7) to release TNF-α and nitric oxide. The prebiotic activities were determined against the beneficial probiotics such as Lactobacillus rhamnosus DR20, Lactobacillus acidophilus LAFTI L10, Bifidobacterium lactis DR10, and Bifidobacterium animalis BB-12. Polysaccharides from the three lupin species have exhibited significant antioxidant, immunostimulatory, and prebiotic activities. The results demonstrated that blue lupins displayed the best activities, and therefore are expected to possess high potential to be used as nutraceutical and functional ingredients with significant therapeutic value. FT-IR spectroscopic technique was employed for a preliminary structural characterization. Studies involving surface morphology and thermal behavior have indicated that the lupin polysaccharides are suitable for end product development.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
•L. angustifolius (blue lupin) polysaccharides (BLPs) extracted & fractionated by SEC.•BLPs displayed antioxidant activities (radical scavenging & chelating abilities).•BLPs also stimulated RAW 264.7 ...cells revealing their immunostimulatory activities.•Direct correlation was found between their bioactivities and galactose content.•BLPs have great potential to be used as nutraceuticals with least toxicity.•Preliminary structural characterisation of BLPs has been undertaken using FT-IR.
Lupinus angustifolius (blue lupin) is produced abundantly in Australia and used mainly as animal feed. However, these seeds have excellent nutritional value with high protein, high dietary fibre and low fat content with a huge potential for value addition. In the present study, blue lupin polysaccharides have been isolated and their biological activities investigated. Hot water extraction and size-exclusion chromatography yielded six polysaccharide fractions that have been designated as BLP-1, BLP-2, BLP-3, BLP-4, BLP-5 and BLP-6. Gas chromatography was employed to determine the mono-sugar compositions of these fractions which showed the existence of galactose, fucose, rhamnose, glucose, mannose, ribose and xylose. The antioxidant activities of all the fractions were investigated using ABTS+* radical scavenging activity and ferrous chelating activity. Immunostimulatory activities of these fractions were measured by treating the mouse macrophages (RAW 264.7) and monitoring the production of nitric oxide (NO) by Griess reagent method. Three of the blue lupin polysaccharides (BLP-1, BLP-2 and BLP-5) displayed significant antioxidant activities. Some of the fractions have effectively stimulated mouse macrophages in a concentration-dependent manner indicating their immunostimulatory capability. FT-IR spectroscopic technique was employed for a preliminary structural characterisation of the active polysaccharide fractions.
N95 respirators, together with eye protection, form vital elements of personal protective equipment (PPE) for healthcare workers (HCW) caring for patients with respiratory infections, such as ...COVID-19. Duckbill N95 respirators are widely used but have a high failure rate when Fit Tested. The commonest site for inward leaks is the region between the nose and maxilla. Safety goggles with an elastic headband may press the upper rim of the respirator against the face, thereby reducing inward leaks. We hypothesized that the use of safety goggles with an elastic headband will improve the overall fit-factor of a duckbill N95 respirator and increase the proportion of users who pass a quantitative Fit Test.
About 60 volunteer HCWs, who had previously failed quantitative Fit Testing with a duckbill N95 respirator, participated in this before-and-after intervention study. A PortaCount® 8048 was used for quantitative Fit Testing. The test was first performed with a duckbill N95 respirator only. It was then repeated after participants donned a pair of safety goggles (3M Fahrenheit, ID 70071531621).
Before the intervention, i.e., with the respirator only, 8 (13.3%) participants passed their Fit Test. This increased to 49 (81.7%) after the application of safety goggles (OR 42, 95% CI 7.14-1697.9,
< 0.0001). The adjusted mean overall fit factor, using Tobit regression analysis, increased from 40.3 to 193.0 (
= 12.32,
< 0.001).
The use of safety goggles with an elastic headband significantly increases the proportion of users who pass a quantitative Fit Test and improves the fit-factor of a duckbill N95 respirator.
Kamal M, Bhatti M, Stewart WC, Johns M, Collins D, Shehabi Y,
. Safety Goggles with Elastic Headband to Improve N95 Fit Following Failed Quantitative Fit Test. Indian J Crit Care Med 2023;27(6):386-391.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Integral membrane proteins perform a wide range of biological processes, including respiration, signal transduction and molecular transport. Structural information is necessary for a full ...understanding of the mechanisms by which integral membrane proteins work. Ferrous iron transporter protein B (FeoB) is an integral membrane protein of Escherichia coli which is considered to transport ferrous iron in to bacteria. But there are no definite proofs or clear indications of the precise mechanism of ferrous transport. By expressing and crystallizing the G-protein domain (FeoGP) and FeoB, it will be helpful to know about the iron transport system. In order to express FeoB and FeoGP, expression vector pFeoB (FeoB in pGEX-4T-1) and pFeoGP (FeoB in pGEX-4T-1) were made. FeoB and FeoGP proteins were expressed and purified. Using vapour diffusion method crystallization trials of FeoB and FeoGP were done. Crystals of FeoGP are observed and no crystal formation for FeoB. Native crystals of FeoGP diffracted to 2.2 ?? resolution, and mant-GMPPNP crystals to 2.6 ??. Preliminary data processing indicate space group P212121 for native crystals, with cell dimensions 46 x 119 x 146 ??. The data set is 100% complete, Rmerge 0.08, and I/ ?? 3.2.
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