450,789 research outputs found
ENHANCED METHOD FOR AMPLIFYING ANTIMICROBIAL ACTIVITY OF LACTOPEROXIDASE SYSTEM IN MILK AND DERIVED PRODUCTS BY CARROT EXTRACT AND BETA CAROTENE
OSCN– has been known and well documented as natural antimicrobial
agent generated from the lactoperoxidase system (LPOS) but the antimicrobial
activity exerted from this system is too low for certain food such as milk and
derived products (up to 1.2 log CFU/ml) resulting in the restriction on industrial
development of LPOS. Our previous study concluded that involvement of carrot
extract and beta carotene in LPOS significantly boosted the antimicrobial activity
(up to 6 log CFU/ml) against S. enteritidis. This finding should be continued to
the application on food. Since we found that LPOS generates low antimicrobial
activity on milk and derived product, our research will be conducted on the
application of LPOS plus carrot extract and beta carotene on milk and derived
product. Because the high antimicrobial activity is needed for industrial
purposes, this research may open the way for industrial development of natural
antimicrobial agent from LPOS.
This research will be conducted in three steps of experiment: (1) ensuring
the incredible antimicrobial activity of LPOS plus carrot extract and beta
carotene against three poisonous tropical bacteria: C. jejuni, S. enteritidis, and E.
coli, (2) utilization of LPOS plus carrot extract and beta carotene in milk: full
cream and skimmed milk, and (3) utilization of LPOS plus carrot extract and beta
carotene in milk derived product: yogurt and tropical fruity milk. The
purification of LPO from bovine milk, the complimentary data analysis for
generation of LPOS antimicrobial activity by the addition of carrot extract and
beta carotene will be conducted in Japan and for the application in tropical
poisonous bacteria, milk, and milk derived product will be conducted in
Indonesia.
The outcomes of this research from three step of research are three
international publications at international‐scopus‐indexed‐journals :
International Journal of Dairy Science and one of patent: “enhanced method for
improvement of LPOS antimicrobial activity by involvement of carrot extract and
beta carotene in milk and derived product”.
Keywords: Lactoperoxidase, antimicrobial activity, carrot extract, beta carotene,
milk, derived products
The antimicrobial activity of oil-in-water microemulsions is predicted by their position within the microemulsion stability zone
It has been shown previously that thermodynamically stable oil-in-water microemulsions have significant antimicrobial activity against planktonic cells and biofilm cells over short periods of exposure. It was the aim of this study to identify whether the position of the microemulsion within the microemulsion stability zone of the pseudo-ternary phase structure predicts the efficiency of the antimicrobial action of the microemulsion. Microemulsions were formulated at different points within the microemulsion stability zone. Experiments were performed to observe the kinetics of killing of these microemulsions against selected test microorganisms (Pseudomonas aeruginosa ATCC 9027, Candida albicans ATCC 10231, Staphylococcus aureus ATCC 6538 and Aspergillus niger ATCC 16404). The results indicated that the antimicrobial activity of the microemulsion is dependant upon its position within the zone of stability and is greater nearer the centre of that zone. The results indicate that significant antimicrobial activity can be observed at all points within the zone of microemulsion stability, but that maximal activity is to be found at the centre of that area
Development and application of an antibiotic spectrum index for benchmarking antibiotic selection patterns across hospitals
Standard metrics for antimicrobial use consider volume but not spectrum of antimicrobial prescribing. We developed an antibiotic spectrum index (ASI) to classify commonly used antibiotics based on activity against important pathogens. The application of this index to hospital antibiotic use reveals how this tool enhances current antimicrobial stewardship metrics.Infect Control Hosp Epidemiol 2017;38:993–997</jats:p
Antimicrobial peptides: agents of border protection for companion animals.
Over the past 20 years, there have been significant inroads into understanding the roles of antimicrobial peptides in homeostatic functions and their involvement in disease pathogenesis. In addition to direct antimicrobial activity, these peptides participate in many cellular functions, including chemotaxis, wound healing and even determination of canine coat colour. Various biological and genetic approaches have helped to elucidate the role of antimicrobial peptides with respect to innate immunity and host defense. Associations of antimicrobial peptides with various skin diseases, including psoriasis, rosacea and atopic dermatitis, have been documented in humans. In the longer term, therapeutic modulation of antimicrobial peptide expression may provide effective new treatments for disease. This review highlights current knowledge about antimicrobial peptides of the skin and circulating leukocytes, with particular focus on relevance to physiology and disease in companion animals
Antidiabetic and antimicrobial activities of fractions and compounds isolated from Berberis brevissima Jafri and Berberis parkeriana Schneid
Methanol extracts of the roots of B. brevissima and B. parkeriana were examined for antidiabetic and antimicrobial activities. Six compounds i.e berberine, 8-oxo-berberine, dehydrocheilanthifoline, columbamine, jatrorrhizine and glutamic acid were isolated from the active fractions of these species for the first time. The antidiabetic activity was determined against Protein Tyrosine Phosphatase 1B (PTP 1B), a negative insulin regulator while the antimicrobial activity was performed against four bacterial strains: Mycobacterium marinum ATCC BAA535, sporadic Methicillin Resistant Staphylococcus aureus (SMRSA), endemic Methicillin Resistant Staphylococcus aureus (EMRSA) and Escherichia coli ATCC.8739 at different concentrations. Amongst the isolated compounds 8-oxo-berberine was found to be the most active antidiabetic (29 % of the positive control) while jatrorrhizine was the most active and selective antimicrobial against SMRSA and EMRSA (-1.2 % of the DMSO (D) control)
Antimicrobial peptide LL-37 and recombinant human mannose-binding lectin express distinct age- and pathogen-specific antimicrobial activity in human newborn cord blood in vitro
Background: There is a need to prevent and treat infection in newborns. One approach is administration of antimicrobial proteins and peptides (APPs) such as LL-37, a membrane-active cathelicidin antimicrobial peptide, and mannose-binding lectin (MBL), a pattern-recognition protein that binds to microbial surface polysaccharides resulting in opsonization and complement activation. Low plasma/serum levels of LL-37 and of MBL have been correlated with infection and exogenous administration of these agents may enhance host defense. Methods: The antimicrobial activity of LL-37 (15 µg/ml) or rMBL (0.5, 2 and 10 µg/ml) was tested in hirudin-anticoagulated preterm and term human cord blood (N = 12-14) against Staphylococcus aureus (SA) USA 300 (2x10 4 CFU/ml), Staphylococcus epidermis (SE) 1457 (2x10 4 CFU/ml) and Candida albicans (CA) SC5314 (1x10 4 CFU/ml). After incubation (1, 45, or 180 min), CFUs were enumerated by plating blood onto agar plates. Supernatants were collected for measurement of MBL via ELISA. Results: Preterm cord blood demonstrated impaired endogenous killing capacity against SA and SE compared to term blood. Addition of LL-37 strongly enhanced antimicrobial/antifungal activity vs SA, SE and CA in term blood and SE and CA in preterm blood. By contrast, rMBL showed modest fungistatic activity vs CA in a sub-analysis of term newborns with high basal MBL levels. Baseline MBL levels varied within preterm and term cohorts with no correlation to gestational age. In summary, exogenous LL-37 demonstrated significant antimicrobial activity against SA, SE and CA in term and SE and CA in preterm human blood tested in vitro. rMBL demonstrated modest antifungal activity in term cord blood of individuals with high baseline MBL levels. Conclusions: To the extent that our in vitro results predict the effects of APPs in vivo, development of APPs for prevention and treatment of infection should take into account host age as well as the target pathogen
Antimicrobial activity of an iron triple helicate
The prevalence of antibiotic resistance has resulted in the need for new approaches to be developed to combat previously easily treatable infections. Here we investigated the potential of the synthetic metallomolecules [Fe2L3]4+ and [Cu2(L’)2]2+ as antibacterial agents. Both molecules have been shown to bind DNA; [Fe2L3]4+ binds in the major groove and causes DNA coiling, whilst [Cu2(L’)2]2+ can act as an artificial nuclease. The work described here shows that only [Fe2L3]4+ is bactericidal for Bacillus subtilis and Escherichia coli. We demonstrate that [Fe2L3]4+ binds bacterial DNA in vivo and, strikingly, that it kills B. subtilis cells very rapidly
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