62 research outputs found

    Phytochemical And Biological Activity Studies On Garcinia Atroviridis Griff. Ex T. Anders.

    Get PDF
    The volatile oil of the fruit of Garcinia atroviridis Griff. ex T. Anders. was isolated by hydrodistillation and analysed by capillary GC and GC-MS, using three columns of different polarity. The oil was dominated by sesquiterpenoids, with the most abundant components being (-)-β-caryophyllene (23.8 %), β-caryophyllene alcohol (15.6 %) and α-humulene (10.7 %). Three of the volatile constituents, β-caryophyllene alcohol (68), ginsenol (70) and (1S,2S,5S,8S)-4,4,8-trimethyltricyclo[6.3.1.01,5]dodecan-2-ol (71) were synthesized and isolated by preparative GC for authentication purposes

    Absolute configuration of 3β-acet­oxy­olean-11,12-aziridin-28,13-β-olide

    Get PDF
    The title compound, C32H49NO4, has been isolated from the dichloro­methane extract of the stem bark of Garcinia atroviridis Griff. ex T. Anders. Rings A and B, B and C, and C and D are trans-fused, whereas rings D and E are cis-fused. Rings A, B, C and E have slightly distorted chair conformations, while ring D is most heavily distorted towards a half-chair conformation owing to the strain induced by the lactonization. The ester group attached to ring A is in an equatorial position

    Želatinski film s mikrokapsulama antocijana izoliranih iz plavog graška (Clitoria ternatea) kao prehrambena ambalaža s učinkom suzbijanja patogenih mikroorganizama

    Get PDF
    Research background. Microbial contamination of food products is one of the significant causes of food spoilage and foodborne illnesses. The use of active packaging films incorporated with antimicrobial agents can be a measure to improve food quality and extend shelf life. Nevertheless, antimicrobial agents such as silver, copper, titanium and zinc in the packaging films have raised concerns among consumers due to toxicity issues. Experimental approach. The current study aims to develop biodegradable gelatine-based edible films incorporated with microcapsules of Clitoria ternatea-derived anthocyanins as a natural antimicrobial agent. The impact of incorporation of microcapsules with anthocyanins on the morphology, thermal, mechanical, water vapour barrier and physicochemical properties of the gelatine films was evaluated in this study. The effectiveness of the developed films against foodborne pathogens and their application for perishable food protection were also investigated. Results and conclusions. The results show that incorporating anthocyanin microcapsules enhances the gelatine film physical and mechanical properties by increasing the thickness, tensile strength, Young\u27s modulus and elongation at break of the films. Scanning electronic microscopy analysis revealed that the film surface morphology with anthocyanin microcapsules had a homogeneous and smooth surface texture compared to the control. The thermogravimetric analysis also showed a slight improvement in the thermal properties of the developed films. Agar well diffusion assay revealed that the developed films exhibit significant inhibition against a broad-spectrum of bacteria. Furthermore, the films composed of gelatine with anthocyanin microcapsules significantly reduced the total viable count of microorganisms in the bean curd during storage for 12 days compared with the control films. Novelty and scientific contribution.Increasing global awareness of healthy and safe food with minimal synthetic ingredients as preservatives has sparked the search for the use of antimicrobial agents of natural origins in active food packaging material. In this study, a safe and effective active packaging film was developed using an environmentally friendly biopolymer, gelatine film incorporated with microcapsules of Clitoria ternatea-derived anthocyanins as a natural antimicrobial agent. This study demonstrated that such a method is not only able to improve the film physical properties but can also significantly prolong the shelf life of food products by protecting them from microbial spoilage.Pozadina istraživanja. Mikrobna kontaminacija je jedan od važnijih uzroka kvarenja hrane i pojave bolesti koje se prenose hranom. Primjenom aktivnih filmova za pakiranje hrane obogaćenih antimikrobnim agensima može se poboljšati kakvoća hrane i produljiti njezina valjanost. No, potrošači su sve više zabrinuti zbog moguće toksičnosti mnogih antimikrobnih agensa koji se primjenjuju u tim filmovima, kao što su srebro, bakar, titan i cink. Eksperimentalni pristup. Svrha je ovoga rada bila izraditi biorazgradive jestive filmove od želatine obogaćene mikrokapsulama antocijana izoliranih iz plavog graška (Clitoria ternatea) kao prirodnih antimikrobnih agensa. Ispitan je utjecaj mikrokapsula s antocijanima na morfologiju, toplinska, mehanička i fizikalno-kemijska svojstva filmova, te njihovu propusnost vodene pare. Također je ispitan učinak dobivenih filmova na patogene mikroorganizme u hrani i zaštitu lako pokvarljivih proizvoda. Rezultati i zaključci. Rezultati pokazuju da su se fizikalna i mehanička svojstva filmova poboljšala s dodatkom mikrokapsula antocijana, koje su povećale gustoću, vlačnu čvrstoću, Youngov modul elastičnosti i istezljivost filma. Ispitivanjem morfoloških značajki pretražnom elektronskom mikroskopijom utvrđeno je da film obogaćen antocijanima imao homogenu i glatku površinu, za razliku od kontrolnog uzorka. Termogravimetrijskom je analizom potvrđeno blago poboljšanje toplinskih svojstava filmova. Difuzijom u jažicama agara otkriveno je da dobiveni filmovi imaju znatan inhibicijski učinak na širok spektar bakterija. Osim toga, filmovi od želatine s dodatkom mikrokapsula antocijana smanjili su ukupni broj živih stanica mikroorganizama u tofuu tijekom 12 dana skladištenja, u usporedbi s kontrolnim uzorcima. Novina i znanstveni doprinos. Veća svijest ljudi o važnosti zdrave i sigurne prehrane sa što manjim udjelom sintetičkih konzervansa potakla je potragu za antimikrobnim agensima iz prirodnih izvora koji se mogu upotrijebiti u materijalima za aktivno pakiranje hrane. U ovom je radu razvijen siguran i učinkovit aktivni ambalažni film s dodatkom ekološki prihvatljivog biopolimera, želatinskog filma obogaćenog mikrokapsulama antocijana izoliranih iz plavog graška (Clitoria ternatea) kao prirodnih antimikrobnih agensa. Istraživanje je pokazalo da se ovom metodom mogu poboljšati fizikalna svojstva filma, ali i bitno produljiti vrijeme skladištenja hrane, jer ih dobiveni film štiti od mikrobnog kvarenja

    A Sugarcane-Bagasse-Based Adsorbent Employed for Mitigating Eutrophication Threats and Producing Biodiesel Simultaneously

    Get PDF
    Eutrophication is an inevitable phenomenon, and it has recently become an unabated threat. As a positive, the thriving microalgal biomass in eutrophic water is conventionally perceived to be loaded with myriad valuable biochemical compounds. Therefore, a sugarcane-bagasse-based adsorbent was proposed in this study to harvest the microalgal biomass for producing biodiesel. By activating the sugarcane-bagasse-based adsorbent with 1.5 M of H2SO4, a highest adsorption capacity of 108.9 ± 0.3 mg/g was attained. This was fundamentally due to the surface potential of the 1.5 M H2SO4 acid-modified sugarcane-bagasse-based adsorbent possessing the lowest surface positivity value as calculated from its point of zero charge. The adsorption capacity was then improved to 192.9 ± 0.1 mg/g by stepwise optimizing the adsorbent size to 6.7–8.0 mm, adsorption medium pH to 2–4, and adsorbent dosage to 0.4 g per 100 mL of adsorption medium. This resulted in 91.5% microalgae removal efficiency. Excellent-quality biodiesel was also obtained as reflected by the fatty acid methyl ester (FAME) profile, showing the dominant species of C16–C18 encompassing 71% of the overall FAMEs. The sustainability of harvesting microalgal biomass via an adsorption-enhanced flocculation processes was also evidenced by the potentiality to reuse the spent acid-modified adsorbent

    Poboljšanje mikrobiološke ispravnosti borovnica pomoću polimernih nanočestica s timolom

    Get PDF
    Research background. The presence of Yersinia enterocolitica on raw food products raises the concern of yersiniosis as most of the berries are consumed raw. This is a challenging issue from the food safety aspect since it could increase the occurrence of foodborne diseases among humans. Thus, it is crucial to implement an effective sanitation before the packaging. Experimental approach. This study aims to synthesize and characterize thymol-loaded polyvinyl alcohol (Thy/PVA) nanoparticles as a sanitizer for postharvest treatment of blueberries. Thy/PVA nanoparticles were characterized by spectroscopic and microscopic approaches, prior to the analyses of antimicrobial properties. Results and conclusions. The diameter size of the nanoparticles was on average 84.7 nm, with a surface charge of −11.73 mV. Based on Fourier transform infrared (FTIR) measurement, the Thy/PVA nanoparticles notably shifted to the frequency of 3275.70, 2869.66, 1651.02 and 1090.52 cm-1. A rapid burst was observed in the first hour of release study, and 74.9 % thymol was released from the PVA nanoparticles. The largest inhibition zone was displayed by methicillin-resistant Staphylococcus aureus (MRSA), followed by Y. enterocolitica and Salmonella typhi. However, amongst these bacteria, the inhibition and killing of Y. enterocolitica required a lower concentration of Thy/PVA nanoparticles. The treatment successfully reduced the bacterial load of Y. enterocolitica on blueberries by 100 %. Novelty and scientific contribution. Thymol is a plant-based chemical without reported adverse effects to humans. In this study, by using the nanotechnology method of encapsulation with PVA, we improved the stability and physicochemical properties of thymol. This nanoparticle-based sanitizer could potentially promote the postharvest microbiological safety of raw berries, which may become an alternative practice of food safety.Pozadina istraživanja. Prisutnost bakterije Yersinia enterocolitica u sirovim prehrambenim proizvodima izaziva zabrinutost zbog moguće pojave jersinioze, s obzirom na to da se bobičasto voće najčešće konzumira sirovo. S aspekta sigurnosti hrane ova bakterija predstavlja problem, jer može povećati učestalost pojave bolesti koje se prenose hranom. Stoga je neophodno provesti učinkovitu sanitaciju voća prije pakiranja. Eksperimentalni pristup. Svrha je ovoga rada bila sintetizirati i okarakterizirati nanočestice poli(vinil-alkohola) s timolom kao dezinficijensom za obradu borovnica prije pakiranja. Nanočestice su okarakterizirane pomoću spektroskopije i mikroskopije, a zatim su ispitana njihova antimikrobna svojstva. Rezultati i zaključci. Prosječni promjer nanočestica bio je 84,7 nm, s površinskim nabojem od −11,73 mV. Rezultati Fourier transformirane infracrvene spektroskopije (FTIR) pokazuju značajan pomak pika nanočestica poli(vinil-alkohola) s timolom prema frekvencijama od 3275,70; 2869,66; 1651,02 i 1090,52 cm-1. Iznenadni porast količine timola oslobođenog iz nanočestica opažen je u prvih sat vremena ispitivanja njegovog kontroliranog otpuštanja, a ukupno je otpušteno 74,9 % timola. Opažena je najveća zona inihbicije rasta bakterije Staphylococcus aureus otporne na meticilin (MRSA), a zatim bakterija Y. enterocolitica i Salmonella typhi. Međutim, za inhibiciju i ubijanje bakterija Y. enterocolitica bile su potrebne manje koncentracije nanočestica poli(vinil-alkohola) s timolom. Ovim je postupkom broj bakterija Y. enterocolitica uspješno smanjen za 100 %. Novina i znanstveni doprinos. Timol je spoj biljnog porijekla, koji ne narušava zdravlje čovjeka. U ovome smo radu inkapsulacijom u omotaču s poli(vinil-alkoholom) povećali stabilnost i poboljšali fizikalno-kemijska svojstva timola. Primjenom nanočestica tog dezinficijensa može se poboljšati mikrobiološka ispravnost sirovog bobičastog voća, što se u praksi može primijeniti za očuvanje sigurnosti hrane

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

    Get PDF
    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

    Get PDF
    Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

    Defining the causes of sporadic Parkinson's disease in the global Parkinson's genetics program (GP2)

    Get PDF
    The Global Parkinson’s Genetics Program (GP2) will genotype over 150,000 participants from around the world, and integrate genetic and clinical data for use in large-scale analyses to dramatically expand our understanding of the genetic architecture of PD. This report details the workflow for cohort integration into the complex arm of GP2, and together with our outline of the monogenic hub in a companion paper, provides a generalizable blueprint for establishing large scale collaborative research consortia

    Multi-ancestry genome-wide association meta-analysis of Parkinson?s disease

    Get PDF
    Although over 90 independent risk variants have been identified for Parkinson’s disease using genome-wide association studies, most studies have been performed in just one population at a time. Here we performed a large-scale multi-ancestry meta-analysis of Parkinson’s disease with 49,049 cases, 18,785 proxy cases and 2,458,063 controls including individuals of European, East Asian, Latin American and African ancestry. In a meta-analysis, we identified 78 independent genome-wide significant loci, including 12 potentially novel loci (MTF2, PIK3CA, ADD1, SYBU, IRS2, USP8, PIGL, FASN, MYLK2, USP25, EP300 and PPP6R2) and fine-mapped 6 putative causal variants at 6 known PD loci. By combining our results with publicly available eQTL data, we identified 25 putative risk genes in these novel loci whose expression is associated with PD risk. This work lays the groundwork for future efforts aimed at identifying PD loci in non-European populations

    Garcinexanthone G, a selective butyrylcholinesterase inhibitor from the stem bark of Garcinia atroviridis

    No full text
    The present study was undertaken to investigate the isolated compounds from the stem bark of Garcinia atroviridis as potential cholinesterase inhibitors and the ligand-enzyme interactions of selected bioactive compounds in silico. The in vitro cholinesterase results showed that quercetin (3) was the most active AChE inhibitor (12.65 ± 1.57 μg/ml) while garcinexanthone G (6) was the most active BChE inhibitor (18.86 ± 2.41 μg/ml). It is noteworthy to note that compound 6 was a selective inhibitor with the selectivity index of 11.82. Molecular insight from docking interaction further substantiate that orientation of compound 6 in the catalytic site which enhanced its binding affinity as compared to other xanthones. The nature of protein-ligand interactions of compound 6 is mainly hydrogen bonding, and the hydroxyl group of compound 6 at C-10 is vital in BChE inhibition activity. Therefore, compound 6 is a notable lead for further drug design and development of BChE selective inhibitor
    corecore