Propolis ethanolic solutions are the most used propolis products on the market for the treatment of minor ulcers in the mouth, angina, thrush or skin infections. Since it is still an unofficial drug ...in pharmacy, we analyzed the contents of flavonoids in ten commercially available ethanolic solutions of propolis from the Croatian market using two complementary colorimetric methods. Antimicrobial activities, determined with the diffusion method, against six bacterial species (Bacillus subtilis NCTC 8236, Staphylococcus aureus ATCC 25923, Streptococcus pyogenes ATCC 12204, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 10536, Pseudomonas aeruginosa ATCC 27853, and one yeast-like fungus Candida albicans ATCC 10231 were compared. Results of flavonoids analysis suggested that the contents of flavones and flavonols in the products were uniform and ranged from 0.14 to 0.41%, but the content of flavanones varied greatly from 0.43 to 18.78%. Total flavonoid content, as the sum of two colorimetric methods, in propolis products was between 0.78 and 18.92%, and most products had the flavonoids content below 9%. All products with the total flavonoids content above 1% showed antimicrobial activity against the four Gram-positive bacterial species tested, and against P. aeruginosa and the yeast-like fungus C. albicans. Total flavonoids contents, expressed as the sum of two colorimetric methods, could be useful methods for estimating the flavonoid contents of propolis products. Our results indicate that the quality of commercially available propolis products requires verification.
Combining conventional drugs and traditional medicine may represent a useful approach to combating antibiotic resistance, which has become a serious threat to global public health. This study aimed ...to evaluate the potential synergistic interactions between Tanreqing (TRQ) injection, a commercial traditional Chinese medicine formula used for the treatment of upper respiratory tract infection, and selected antibiotics used against methicillin-resistant Staphylococcus aureus (MRSA).
The minimum inhibitory concentrations (MICs) of TRQ, vancomycin and linezolid against planktonic MRSA strain were determined by the broth microdilution method. The combined effects of TRQ and antibiotics were studied by the checkerboard method and the time-kill curve assay. The 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) reduction assay was employed to determine the inhibitory effect of the test compounds alone and in combination against MRSA embedded in biofilms.
MRSA strain was found to be susceptible to TRQ formula with MIC value 4125 μg/ml, while the MIC values for antibiotics, vancomycin and linezolid, were 2.5 μg/ml. The checkerboard analysis revealed that TRQ markedly enhanced activities of the tested antibiotics by reducing their MICs. In the time-kill analysis, TRQ at 1/2 × MIC in combination with vancomycin at 1/2 × MIC, as well as TRQ at 1/8 × MIC in combination with linezolid at 1/2 × MIC decreased the viable colonies by ≥2log10 CFU/ml, resulting in a potent synergistic effect against planktonic MRSA. In contrast to the tested antibiotics, which did not affect mature MRSA biofilms at subinhibitory concentrations, TRQ alone showed strong ability to disrupt preformed biofilms and induce biofilm cell death. The combination of TRQ with vancomycin or linezolid at sub-MIC concentrations resulted in a synergistic antibiofilm effect significantly higher than for each single agent.
This study provides the first in vitro evidence on the synergistic effects of TRQ and vancomycin or linezolid against planktonic and biofilm MRSA, and revealed their optimal combination doses, thereby providing a rational basis for the combination therapies against MRSA.
A series of porphyrins, tetrapyrrole natural organic compounds, are evaluated here as endogenous anti-inflammatory agents. They directly inhibit the activity of Fyn, a non-receptor Src-family ...tyrosine kinase, triggering anti-inflammatory events associated with down-regulation of T-cell receptor signal transduction, leading to inhibition of tumor necrosis factor alpha (TNF-α) production. This is one of the major pro-inflammatory cytokines, associated with diseases such as diabetes, tumorigenesis, rheumatoid arthritis, and inflammatory bowel disease. Porphyrins, as a chemical class, inhibited Fyn kinase activity in a non-competitive, linear-mixed fashion. In cell-based in vitro experiments on polymorphonuclear cells, porphyrins inhibited TNF-α cytokine production, T-cell proliferation, and the generation of free radicals in the oxidative burst, in a concentration-related manner. In vivo, lipopolysaccharide-induced TNF-α production in mice was inhibited by several of the porphyrins. These findings may be very important for the overall understanding of the role(s) of porphyrins in inflammation and their possible application as new anti-inflammatory agents.
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Migraine is one of the most common neurological disorder, which has long been related to brain serotonin (5-HT) depletion and neuro-inflammation. Despite many treatment options are available, the ...frequent occurrence of unacceptable adverse effects further supports the research toward nutraceuticals and herbal preparations, among which Tanacetum parthenium and Salix alba showed promising anti-inflammatory and neuro-modulatory activities.
The impact of extract treatment on astrocyte viability, spontaneous migration and apoptosis was evaluated. Anti-inflammatory/anti-oxidant effects were investigated on isolated rat cortexes exposed to a neurotoxic stimulus. The lactate dehydrogenase (LDH) release, nitrite levels and 5-HT turnover were evaluated, as well. A proteomic analysis was focused on specific neuronal proteins and a fingerprint analysis was carried out on selected phenolic compounds.
Both extracts appeared able to exert in vitro anti-oxidant and anti-apoptotic effects. S. alba and T. parthenium extracts reduced LDH release, nitrite levels and 5-HT turnover induced by neurotoxic stimulus. The downregulation of selected proteins suggest a neurotoxicity, which could be ascribed to an elevated content of gallic acid in both S. alba and T. parthenium extracts.
Concluding, both extracts exert neuroprotective effects, although the downregulation of key proteins involved in neuron physiology suggest caution in their use as food supplements.
•S. alba and T. parthenium water extracts as sources of anti-oxidant compounds.•Neuroprotective and anti-apoptotic effects in vitro.•Antioxidant effects of extracts in cortical spreading depression.•Downregulation of key proteins involved in neuron morphology and physiology.•Caution in the use of S. alba and T. parthenium-enriched food supplements.
The polyphenolic composition and anti-inflammatory activity of selected
Thymus
species (
T. longicaulis
C. Presl,
T. praecox
Opiz subsp.
polytrichus
(A. Kerner Ex Borbás) Jalas,
T. pulegioides
L.,
T. ...serpyllum
L. subsp.
serpyllum
and
T. striatus
Vahl) was studied in comparison with
T. vulgaris
, as an officinal medicinal plant, to evaluate the biomedical potential of these Croatian wild-growing species. This paper provides a first insight into the polyphenolic profiles of
T
.
praecox
subsp.
polytrichus
and
T. striatus
. Also, some flavone and hydroxycinnamic derivatives were at first identified in the other studied species by LC-DAD-ESI–MS/MS analysis. Rosmarinic acid and glycosides of scutellarein and luteolin were found to be the most abundant polyphenolic constituents. The
Thymus
extracts inhibited Src tyrosine kinase activity and they reduced the production of proinflammatory cytokine interleukin-6 in Balb/C mice splenocytes. The obtained results highlighted
T. longicaulis
as a potential source of herbal drugs with anti-inflammatory properties and/or novel functional food rich in flavonoids and phenolic acids.
Aim： To investigate the mechanisms underlying the protective effects of quercetin-rutinoside （rutin） and its aglycone quercetin against CCl4-induced liver damage in mice. Methods： BALB/cN mice were ...intraperitoneally administered rutin （10, 50, and 150 mg/kg） or quercetin （50 mg/kg） once daily for 5 consecutive days, followed by the intraperitoneal injection of CCl4 in olive oil （2 mL/kg, 10% v/v）. The animals were sacrificed 24 h later. Blood was collected for measuring the activities of ALT and AST, and the liver was excised for assessing Cu/Zn superoxide dismutase （SOD） activity, GSH and protein concentrations and also for immunoblotting. Portions of the livers were used for histology and immunohistochemistry.Results： Pretreatment with rutin and, to a lesser extent, with quercetin significantly reduced the activity of plasma transaminases and improved the histological signs of acute liver damage in CCl4-intoxicated mice. Quercetin prevented the decrease in Cu/Zn SOD activity in CCl4-intoxicated mice more potently than rutin. However, it was less effective in the suppression of nitrotyrosine formation. Quercetin and, to a lesser extent, rutin attenuated the inflammation in the liver by down-regulating the CCl4-induced activation of nuclear factor-kappa B （NF-κB）, tumor necrosis factor-α （TNF-α） and cyclooxygenase （COX-2）. The expression of inducible nitric oxide synthase （iNOS） was more potently suppressed by rutin than by quercetin. Treatment with both flavonoids significantly increased NF-E2-related factor 2 （Nrf2） and heme oxygenase （HO-1） expression in injured livers, although quercetin was less effective than rutin at an equivalent dose. Quercetin more potently suppressed the expression of transforming growth factor-β1 （TGF-β1） than rutin.Conclusion： Rutin exerts stronger protection against nitrosative stress and hepatocellular damage but has weaker antioxidant and anti-inflammatory activities and antifibrotic potential than quercetin, which may be attributed to the presence of a rutinoside moiety in position 3 of the C ring.
L. has long been known for its medicinal properties and isolation of ingredients whose derivatives are used for therapeutic purposes. The CYP2B6 and CYP3A4 enzymes belong to a large family of ...cytochrome P450 enzymes. These enzymes are involved in the metabolism of drugs and other xeonobiotics. It is known that various compounds can induce or inhibit the activity of these enzymes. The aim of this study was to investigate the nature of the inhibitory effect of
extract on CYP2B6 and CYP3A4 enzymes, as well as the type of inhibition, the presence of reversible or pseudo-irreversible inhibition, and the possible heme destruction. The methanolic extract of
showed an inhibitory effect on CYP2B6 (by almost 90%) and CYP3A4 enzymes (by almost 70%). A significant decrease in heme concentration by 46.8% and 38.2% was observed in different assays. These results clearly indicate that the studied plant extracts significantly inhibited the activity of CYP2B6 and CYP3A4 enzymes. Moreover, they showed irreversible inhibition, which is even more important for possible interactions with drugs and dietary supplements.
Cosmetic products are complex mixtures of ingredients with different physical, chemical and functional properties formulated in order to obtain the product with desired activity and quality. This ...paper provides a comprehensive review on the effectiveness of the environmentally friendly extraction technique based on the application of GRAS solvent CO2 and high pressures which present many advantages over the conventional processes. Supercritical CO2 (SCO2) proved to be a promising extraction solvent in this process and has the potential to replace the organic toxic solvents. Due to its unique properties, the desirable texture, absence of water or solvent traces, chemical stability and presence of bioactive agents, SCO2 extracts can be easily incorporated into the cosmetic products. Depending on the plant material, the operation parameters and the chemical profile, the obtained extracts can be used as the common cosmetic ingredients (thickeners, emollients, waxes, fragrances, and colorants). Moreover, SCO2 provides a high concentration of bioactive compounds in the final extracts which exhibit many bioactivities in the cosmetic products acting as antioxidants, anti-ageing, photo-protective agents or providing antibacterial activity and inhibition of enzymes, such as tyrosinase, lipoxygenase, collagenase and hyaluronidase. This review highlights the potential application of the SCO2 extracts in the cosmetic industry. The bioactive properties of SCO2 extracts are discussed and their capability for skin health is evaluated.
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•Supercritical CO2 is green extraction solvent suitable for cosmetic purposes.•SCO2 extracts can be easily incorporated into the cosmetic products.•SCO2 extracts are highly concentrated in bioactive compounds.
The phenolic profile of wines is often used to evaluate their quality and authenticity. The phenolic composition of twenty-five commercial wines produced in different Croatian regions from eight red ...and nine white grape varieties was studied. A total of twenty-four polyphenols were analyzed using HPLC-DAD and classified into five groups based on their structure: phenolic acids, flavan-3-ols, anthocyanins, flavonoids, and stilbenes. The red wines contained higher concentrations of phenolic constituents than the white wines, of which gallic acid (11.8–90.3 mg/L), procyanidin B1 (13.7–63.8 mg/L), and catechin (10.5–34.5 mg/L) were the most abundant. In contrast to the white wines, great variability was observed in the red wines, with the autochthonous Plavac Mali and Babić showing the most specific phenolic profiles. The most representative phenolic components in the studied Croatian wines showed strong antioxidant activity. Gallic acid proved to be the most effective DPPH (IC50 = 0.33 µg/mL) and NO scavenger (IC50 = 12.36 µg/mL), while myricetin was the most potent inhibitor of lipid peroxidation (IC50 = 1.68 µg/mL). Our research has contributed to the characterization and varietal differentiation of Croatian wines, highlighting those rich in certain polyphenols as potential nutraceuticals.
The objective of this study was to spectrophotometric determinate the total phenolic, flavonoid, hydroxycinnamic acid, and flavonol content of orange, pineapple, and apple juices fortified with wild ...thyme (Thymus serpyllum L.), Dalmatian sage (Salvia officinalis L.), and wild thyme-Dalmatian sage (3:1, v/v) extracts, and to evaluate their DPPH radical scavenging activity as a contribution to the development of a new functional beverage. The plant extracts addition increased the amount of phenolic compounds in fruit juices and improved their antioxidant properties. The highest concentrations of bioactive compounds and the greatest DPPH radical activity were obtained by adding Dalmatian sage extract to orange juice. Our study provides the novelty of fortifying fruit juices with wild thyme and Dalmatian sage extracts and offers significant potential for the creation of functional beverages. Keywords: Thymus serpyllum L., Salvia officinalis L., phenolic compounds, DPPH, functional beverages, spectrophotometry.
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