scholarly journals Melanin: Production from Cheese Bacteria, Chemical Characterization, and Biological Activities

2021 ◽  
Vol 18 (20) ◽  
pp. 10562
Author(s):  
Ana Rita Ferraz ◽  
Rita Pacheco ◽  
Pedro D. Vaz ◽  
Cristina S. Pintado ◽  
Lia Ascensão ◽  
...  
Keyword(s):  
Biological Activities ◽  
Acetylcholinesterase Inhibitor ◽  
Current Trend ◽  
Chemical Characterization ◽  
Cholesterol Absorption ◽  
Brown Pigment ◽  
Melanin Production ◽  
Caco2 Cell ◽  
Mueller Hinton ◽  
Mueller Hinton Broth

Pigments are compounds of importance to several industries, for instance, the food industry, where they can be used as additives, color intensifiers, and antioxidants. As the current trend around the world is shifting to the use of eco-friendly commodities, demand for natural dyes is increasing. Melanins are pigments that are produced by several microorganisms. Pseudomonas putida ESACB 191, isolated from goat cheese rind, was described as a brown pigment producer. This strain produces a brown pigment via the synthetic Müeller-Hinton Broth. This brown compound was extracted, purified, analyzed by FTIR and mass spectrometry, and identified as eumelanin. The maximum productivity was 1.57 mg/L/h. The bioactivity of eumelanin was evaluated as the capacity for scavenging free radicals (antioxidant activity), EC50 74.0 ± 0.2 μg/mL, and as an acetylcholinesterase inhibitor, with IC50 575 ± 4 μg/mL. This bacterial eumelanin did not show cytotoxicity towards A375, HeLa Kyoto, HepG2, or Caco2 cell lines. The effect of melanin on cholesterol absorption and drug interaction was evaluated in order to understand the interaction of melanin present in the cheese rind when ingested by consumers. However, it had no effect either on cholesterol absorption through an intestinal simulated barrier formed by the Caco2 cell line or with the drug ezetimibe.

scholarly journals Chemical composition and biological activity of the acetone extract of Ambrosia artemisiifolia L. pollen

2008 ◽  
Vol 73 (11) ◽  
pp. 1039-1049 ◽  
Author(s):  
Slavica Solujic ◽  
Slobodan Sukdolak ◽  
Nenad Vukovic ◽  
Neda Niciforovic ◽  
Snezana Stanic
Keyword(s):  
Biological Activities ◽  
Bacterial Species ◽  
Ambrosia Artemisiifolia ◽  
Acetone Extract ◽  
Diffusion Method ◽  
Chemical Components ◽  
Microdilution Method ◽  
Mueller Hinton ◽  
Broth Dilution ◽  
Mueller Hinton Broth

In this study, the chemical components, antimicrobial and genotoxic biological activities of the acetone extract of Ambrosia artemisiifolia L. pollen were examined. Two lactones were identified: ambrosin and artesovin. The antimicrobial activity of the acetone extract of A. artemisiifolia L. pollen was examined on ten different bacterial species using the disc diffusion method and the microdilution method in Mueller-Hinton broth dilution. The minimal inhibitory concentration of the acetone extract of A. artemisiifolia pollen varied between 1.25-6.50 mg mL-1. The genotoxic effect of the acetone extract of A. artemisiifolia pollen on a eukaryotic model system Drosophila melanogaster was investigated using the SLRL test.

ANTICANCER EFFECT OF UVARIA GENUS

2014 ◽  
pp. 98-101
Author(s):  
Thi Bich Hien Le ◽  
Viet Duc Ho ◽  
Thi Hoai Nguyen
Keyword(s):  
Biological Activities ◽  
Current Trend ◽  
Healthcare Systems ◽  
Chemical Compositions ◽  
Cancer Therapies ◽  
Pharmacological Effects ◽  
Anticancer Effect ◽  
Anti Cancer ◽  
Tropical Areas ◽  
Cancer Activity

Nowadays, cancer treatment has been a big challenge to healthcare systems. Most of clinical anti-cancer therapies are toxic and cause adverse effects to human body. Therefore, current trend in science is seeking and screening of natural compounds which possess antineoplastic activities to utilize in treatment. Uvaria L. - Annonaceae includes approximately 175 species spreading over tropical areas of Asia, Australia, Africa and America. Studies on chemical compositions and pharmacological effects of Uvaria showed that several compound classes in this genus such as alkaloid, flavonoid, cyclohexen derivaties, acetogenin, steroid, terpenoid, etc. indicate considerable biological activities, for example anti-tumor, anti-cancer, antibacterial, antifungal, antioxidant, etc. Specifically, anti-cancer activity of fractions of extract and pure isolated compounds stands out for cytotoxicity against many cancer cell lines. This study provides an overview of anti-cancer activity of Uvaria and suggests a potential for further studies on seeking and developing novel anti-cancer compounds. Key words: Anti-cancer, Uvaria.

scholarly journals Biocompatibility and radioprotection by newly characterized melanin pigment and its production from Dietzia schimae NM3 in optimized whey medium by response surface methodology

2021 ◽  
Vol 71 (1) ◽  
Author(s):  
Sahar Eskandari ◽  
Zahra Etemadifar
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Nutrient Broth ◽  
Tyrosinase Activity ◽  
Brown Pigment ◽  
Scavenging Activity ◽  
Protection Factor ◽  
Melanin Production

Abstract Purpose To characterize and optimize the productivity of melanin using an extremotolerant actinobacterium, Dietzia schimae NM3, for the first time. Methods An extracellular brown pigment produced by D. schimae NM3 in the nutrient broth and cheese whey medium by adding L-tyrosine. The extracted melanin was analyzed by UV-visible, HPLC, and FTIR assays. The radical scavenging activity (by DPPH) and sun protection factor (SPF) of the extracted melanin were measured. The melanin cytotoxicity was assayed by MTT and chromate biosorption was measured by atomic absorption spectroscopy. Finally, melanin production by D. schimae NM3 was optimized by response surface methodology (RSM) using Box-Behnken design in the whey medium. Result The purified melanin showed similar peak to the standard melanin (SIGMA) at 3.5 min in HPLC, and C=O bands, NH2, CH, C-N, and aromatic groups by FTIR. The radical scavenging activity (by DPPH) and SPF of the extracted melanin were obtained 188.9% and 20.22, respectively. Using MTT assay, the melanin revealed non-toxic effect on the normal human fibroblast (HFB) cell culture. The melanin yield 790 mg l−1, and tyrosinase activity 3400 U ml−1 were obtained in the medium contained whey powder [5% (w v−1)], L-tyrosine 2.5 g l−1, CuSO4 0.013 g l−1, and pH 10.5, incubated at 32 °C for 3 days. The ANOVA results indicated significant P-value, model F-value, and probability, with insignificant lack of fit. After optimization with mono-factors, the nutrient broth came up with melanin yield as 1.2 g l−1 and tyrosinase activity as 4040 U ml−1. Conclusion This is the first report of melanin production by D. schimae NM3 and this natural melanin showed valuable biological properties such as high antioxidant activity and radioprotection (SPF) and the biocompatibility to human cell line.

scholarly journals Recording the Presence of Peanibacillus larvae larvae Colonies on MYPGP Substrates Using a Multi-Sensor Array Based on Solid-State Gas Sensors

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4917
Author(s):  
Beata Bąk ◽  
Jakub Wilk ◽  
Piotr Artiemjew ◽  
Jerzy Wilde
Keyword(s):  
Gas Sensors ◽  
Culture Media ◽  
Laboratory Diagnosis ◽  
Baseline Correction ◽  
American Foulbrood ◽  
Sensor Signal ◽  
Sodium Pyruvate ◽  
Mueller Hinton ◽  
Regeneration Phase ◽  
Mueller Hinton Broth

American foulbrood is a dangerous disease of bee broods found worldwide, caused by the Paenibacillus larvae larvae L. bacterium. In an experiment, the possibility of detecting colonies of this bacterium on MYPGP substrates (which contains yeast extract, Mueller-Hinton broth, glucose, K2HPO4, sodium pyruvate, and agar) was tested using a prototype of a multi-sensor recorder of the MCA-8 sensor signal with a matrix of six semiconductors: TGS 823, TGS 826, TGS 832, TGS 2600, TGS 2602, and TGS 2603 from Figaro. Two twin prototypes of the MCA-8 measurement device, M1 and M2, were used in the study. Each prototype was attached to two laboratory test chambers: a wooden one and a polystyrene one. For the experiment, the strain used was P. l. larvae ATCC 9545, ERIC I. On MYPGP medium, often used for laboratory diagnosis of American foulbrood, this bacterium produces small, transparent, smooth, and shiny colonies. Gas samples from over culture media of one- and two-day-old foulbrood P. l. larvae (with no colonies visible to the naked eye) and from over culture media older than 2 days (with visible bacterial colonies) were examined. In addition, the air from empty chambers was tested. The measurement time was 20 min, including a 10-min testing exposure phase and a 10-min sensor regeneration phase. The results were analyzed in two variants: without baseline correction and with baseline correction. We tested 14 classifiers and found that a prototype of a multi-sensor recorder of the MCA-8 sensor signal was capable of detecting colonies of P. l. larvae on MYPGP substrate with a 97% efficiency and could distinguish between MYPGP substrates with 1–2 days of culture, and substrates with older cultures. The efficacy of copies of the prototypes M1 and M2 was shown to differ slightly. The weighted method with Canberra metrics (Canberra.811) and kNN with Canberra and Manhattan metrics (Canberra. 1nn and manhattan.1nn) proved to be the most effective classifiers.

scholarly journals Chemical characterization and biological activities of two varieties of xoconostle fruits Opuntia joconostle F.A.C. Weber ex Diguet and Opuntia matudae Scheinvar

2019 ◽  
Vol 10 (6) ◽  
pp. 3181-3187
Author(s):  
Natalia Moraleja Garcia-Saavedra ◽  
Lillian Barros ◽  
Filipa S. Reis ◽  
Custódio Lobo Roriz ◽  
Maria José Alves ◽  
...  
Keyword(s):  
Biological Activities ◽  
Chemical Characterization ◽  
Good Source

Xoconostle fruits are a good source of healthy compounds.

scholarly journals In Vitro Activities of Daptomycin against 2,789 Clinical Isolates from 11 North American Medical Centers

2001 ◽  
Vol 45 (6) ◽  
pp. 1919-1922 ◽  
Author(s):  
Arthur L. Barry ◽  
Peter C. Fuchs ◽  
Steven D. Brown
Keyword(s):  
Clinical Isolates ◽  
In Vitro Activity ◽  
Broth Microdilution ◽  
In Vitro Susceptibility ◽  
Medical Centers ◽  
Mueller Hinton ◽  
Calcium Cations ◽  
Important Exception ◽  
Mueller Hinton Broth

ABSTRACT The in vitro activity of daptomycin is affected by the concentration of calcium cations in the test medium. Mueller-Hinton broth is currently adjusted to contain 10 to 12.5 mg of magnesium per liter and 20 to 25 mg of calcium per liter, but for testing of daptomycin, greater concentrations of calcium (50 mg/liter) are recommended to better resemble the normal concentration of ionized calcium in human serum. Two levels of calcium were used for broth microdilution tests of 2,789 recent clinical isolates of gram-positive bacterial pathogens. MICs of daptomycin were two- to fourfold lower when the broth contained additional calcium. For most species, however, the percentages of strains that were inhibited by 2.0 μg of daptomycin per ml were essentially identical with the two broth media. Enterococci were the important exception; i.e., 92% were inhibited when tested in calcium-supplemented broth but only 35% were inhibited by 2.0 μg/ml without the additional calcium. This type of information should be considered when selecting criteria for defining in vitro susceptibility to daptomycin.

Effect of Ethanol/Trisodium Citrate Lock on Microorganisms Causing Hemodialysis Catheter-Related Infections

2007 ◽  
Vol 8 (4) ◽  
pp. 262-267 ◽  
Author(s):  
T.A. Takla ◽  
S.A. Zelenitsky ◽  
L.M. Vercaigne
Keyword(s):  
In Vitro Study ◽  
Trisodium Citrate ◽  
Methicillin Resistant ◽  
Hemodialysis Catheter ◽  
E Coli ◽  
Lock Solution ◽  
Mueller Hinton ◽  
Mueller Hinton Broth ◽  
Made In

Purpose This in vitro study tested the effectiveness of a novel 30% ethanol/4% trisodium citrate (TSC) lock solution against the most common pathogens causing hemodialysis catheter-related infections. Methods Clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) (n=4), methicillin-sensitive S. aureus (MSSA) (n=8), methicillin-resistant Staphylococcus epidermidis (MRSE) (n=8), Pseudomonas aeruginosa (n=4) and Escherichia coli (n=4) were tested in duplicate. Bacterial suspensions of each isolate were made in a control solution of normal saline and Mueller-Hinton broth (MHB), and in a lock solution of ethanol 30%, TSC 4% and MHB. Suspensions were incubated at 37 °C for 48 h. Colony counts were determined from samples collected at t=0 h (before exposure to the ethanol/TSC lock), t=1 h (one hour after exposure to the ethanol/TSC lock), t=24 h and t=48 h. To confirm the absence of viable organisms in the lock solution, the remaining volume at 48 h was filtered through a 0.45 μm filter. The filter was rinsed with 15 mL sterile water and plated on tryptic soy agar (TSA). Results All controls demonstrated significant growth over 48 h. In the lock solutions, initial inocula were reduced to 0 viable colonies by t=1 h (6-log kill), and there was no growth at t=24 and 48 h. Filtering of lock solutions also showed no growth. These results were consistent among duplicates of all isolates. Conclusions The 30% ethanol/4% TSC lock solution consistently eradicated MRSA, MSSA, MRSE, P. aeruginosa and E. coli within 1 h of exposure. Experiments are currently underway to test this novel lock solution on preventing biofilm production by these pathogens.

scholarly journals The Bioavailability and Biological Activities of Phytosterols as Modulators of Cholesterol Metabolism

Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 523
Author(s):  
Xiang Li ◽  
Yan Xin ◽  
Yuqian Mo ◽  
Pavel Marozik ◽  
Taiping He ◽  
...  
Keyword(s):  
Cholesterol Metabolism ◽  
Biological Activities ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Cholesterol Absorption ◽  
The Body ◽  
Research Progress ◽  
Intestinal Lumen ◽  
Dose Response Relationship ◽  
Liver X Receptor Α

Phytosterols are natural sterols widely found in plants that have a variety of physiological functions, and their role in reducing cholesterol absorption has garnered much attention. Although the bioavailability of phytosterols is only 0.5–2%, they can still promote cholesterol balance in the body. A mechanism of phytosterols for lowering cholesterol has now been proposed. They not only reduce the uptake of cholesterol in the intestinal lumen and affect its transport, but also regulate the metabolism of cholesterol in the liver. In addition, phytosterols can significantly reduce the plasma concentration of total cholesterol, triglycerides, and low-density lipoprotein cholesterol (LDL-C), with a dose-response relationship. Ingestion of 3 g of phytosterols per day can reach the platform period, and this dose can reduce LDL-C by about 10.7%. On the other hand, phytosterols can also activate the liver X receptor α-CPY7A1 mediated bile acids excretion pathway and accelerate the transformation and metabolism of cholesterol. This article reviews the research progress of phytosterols as a molecular regulator of cholesterol and the mechanism of action for this pharmacological effect.

scholarly journals Chemical Characterization and Biological Activities of Essential Oil Obtained from Mint Timija Cultivated under Mineral and Biological Fertilizers

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Ayoub Kasrati ◽  
Chaima Alaoui Jamali ◽  
Robert Spooner-Hart ◽  
Laurent Legendre ◽  
David Leach ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Arbuscular Mycorrhizae ◽  
Biological Activities ◽  
Chemical Characterization ◽  
Mineral Fertilizer ◽  
Agronomic Practices ◽  
Significant Difference ◽  
Vesicular Arbuscular ◽  
Promising Solution ◽  
Biological Fertilizer

Cultivation of mint timija (Mentha suaveolens subsp. timija (Briq.) Harley) constitutes a promising solution to the conservation and sustainable utilization of this Moroccan endemic and threatened species. Optimized agronomic practices require mineral and/or biological fertilizer applications. The aim of this study was to determine the effects of application of a complete (N, P, and K) mineral fertilizer and vesicular arbuscular mycorrhizae (VAM) inoculation on the composition, antioxidant, and insecticidal properties of mint timija essential oils (EOs). The GC-MS analyses identified 27 components representing more than 99.9% of the total oils. Menthone (40.7–49.3%), pulegone (31.3–36.5%), and isomenthone (2.5–4.4%) were found to be the main constituents. Cultivation of mint timija with mineral fertilizer and VAM inoculation induced an increase in menthone content and a parallel decrease of pulegone. Both treatments enhanced the antioxidant activity of the investigated EOs in all assays (IC50 ranged from 2.34 ± 0.03 mg/mL to 6.82 ± 0.25 mg/mL), while no significant difference in the toxicities of these oils against Tribolium confusum du Val. has been observed. Overall, we conclude that cultivation using complete mineral fertilizer and VAM inoculation could be useful in modulating the chemical composition and enhancing the antioxidant activity of the EO of this endemic Moroccan species.

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