extraction of polyphenols Dotaz Zobrazit nápovědu
Passiflora species, mangosteen, and cherimoya peels are a source of bioactive phenolic compounds. Nevertheless, a significant fraction of polyphenols, called non-extractable polyphenols (NEPs), are retained in the extraction residue after a conventional extraction. Thus, alkaline, acid, and enzymatic-assisted extractions to recover high contents of antioxidant NEPs from the extraction residue of fruit peels, were compared in this work. A high-performance thin-layer chromatography method with UV/Vis detection was developed in order to obtain the phenolic profile for the extracts. The most intense bands were further analyzed by direct analysis in real-time-high-resolution mass spectrometry to tentatively identified NEPs in fruit peel extracts. Total phenolic and proanthocyanidin contents and antioxidant capacity of the extracts were measured to carry out a multivariate statistical analysis. Alkaline hydrolysis was the most efficient treatment to recover NEPs from fruit peels as well as a promising treatment to obtain antioxidant extracts along with EAE. Cherimoya peel extracts were the richest in antioxidant NEPs. This work highlights that many NEPs remain on the extraction residue of fruit peels after conventional extraction and are not usually taken into account.
The phenomenon of antibiotic resistance has been recognized as one of the greatest threats to humanity. Therefore, there is an enormous need to introduce new antibiotics to the medical practice that will effectively eradicate the resistant bacterial strains threatening human health and life. One solution currently being considered as an alternative to antibiotics involves secondary metabolites of plants that can be used in modern antibacterial therapy. Polyphenols represent a broad and diversified group of plant-derived aromatic compounds. Their antibacterial potential has been recognized via specific mechanisms of action, e.g., by inhibition of bacterial biofilm formation, through synergistic effects with the action of currently used antibiotics, and by inhibition of the activity of bacterial virulence factors.
- MeSH
- antibakteriální látky * farmakologie MeSH
- Bacteria MeSH
- lidé MeSH
- polyfenoly * farmakologie MeSH
- rostlinné extrakty farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The ingestion of contaminated water and food is known to cause food illness. Moreover, on assessing the patients suffering from foodborne disease has revealed the role of microbes in such diseases. Concerning which different methods have been developed for protecting food from microbes, the treatment of food with chemicals has been reported to exhibit an unwanted organoleptic effect while also affecting the nutritional value of food. Owing to these challenges, the demand for natural food preservatives has substantially increased. Therefore, the interest of researchers and food industries has shifted towards fruit polyphenols as potent inhibitors of foodborne bacteria. Recently, numerous fruit polyphenols have been acclaimed for their ability to avert toxin production and biofilm formation. Furthermore, various studies have recommended using fruit polyphenols solely or in combination with chemical disinfectants and food preservatives. Currently, different nanoparticles have been synthesized using fruit polyphenols to curb the growth of pathogenic microbes. Hence, this review intends to summarize the current knowledge about fruit polyphenols as antibacterial agents against foodborne pathogens. Additionally, the application of different fruit extracts in synthesizing functionalized nanoparticles has also been discussed.
- MeSH
- antibakteriální látky chemie farmakologie MeSH
- Bacteria účinky léků metabolismus MeSH
- biofilmy účinky léků MeSH
- lidé MeSH
- nanočástice MeSH
- ovoce chemie MeSH
- polyfenoly chemie farmakologie MeSH
- potravinářská mikrobiologie MeSH
- potravinářské konzervační látky chemie farmakologie MeSH
- rostlinné extrakty chemie farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Klíčová slova
- pozitivní účinky, negativní účinky,
- MeSH
- antikarcinogenní látky MeSH
- antioxidancia * fyziologie MeSH
- bezpečnost * MeSH
- fytoestrogeny škodlivé účinky MeSH
- karcinogeny MeSH
- kardiovaskulární nemoci prevence a kontrola MeSH
- lékové interakce MeSH
- lidé MeSH
- mutageny škodlivé účinky MeSH
- polyfenoly * fyziologie metabolismus škodlivé účinky terapeutické užití MeSH
- potravní doplňky škodlivé účinky MeSH
- rostlinné extrakty MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
Global obesity rates are of epidemic proportion. With limited treatments available there is a large demand for therapeutic alternatives. Polyphenols derived from coloured rice varieties may serve as a potential functional food alternative in combating obesity and obesity-related diseases. The antioxidant and anti-inflammatory properties of polyphenols found in coloured rice varieties could have the ability to neutralize oxidative stress and modulate inflammatory responses in obese populations. This review discusses polyphenols derived from rice, the oxidative stress and inflammatory pathways involved in obesity pathogenesis, bioavailability of polyphenols and the therapeutic potential of polyphenols on transcriptional and molecular pathways related to obesity and obesity-related diseases.
- MeSH
- antioxidancia metabolismus MeSH
- LDL-cholesterol účinky léků MeSH
- lidé MeSH
- obezita farmakoterapie metabolismus patofyziologie MeSH
- oxidační stres účinky léků MeSH
- polyfenoly farmakologie terapeutické užití MeSH
- reaktivní formy kyslíku metabolismus MeSH
- rostlinné extrakty MeSH
- rýže (rod) chemie MeSH
- tukové buňky metabolismus účinky léků MeSH
- zánět metabolismus patofyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Pressure-driven membrane-based technologies represent a valid approach to reduce the environmental pollution of several agro-food by-products. Recently, in relation to the major interest for natural compounds with biological activities, their use has been also addressed to the recovery, separation and fractionation of phenolic compounds from such by-products. In particular, tight ultrafiltration (UF) and nanolfiltration (NF) membranes have been recognized for their capability to recover phenolic compounds from several types of agro-food by-products. The separation capability of these membranes, as well as their productivity, depends on multiple factors such as membrane material, molecular weight cut-off (MWCO) and operating conditions (e.g., pressure, temperature, feed flow rate, volume reduction factor, etc.). This paper aims at providing a critical overview of the influence of these parameters on the recovery of phenolic compounds from agro-food by-products by using tight UF and NF membranes. The literature data are analyzed and discussed in relation to separation processes, molecule properties, membrane characteristics and other phenomena occurring in the process. Current extraction methodologies of phenolic compounds from raw materials are also introduced in order to drive the implementation of integrated systems for the production of actractive phenolic formulations of potential interest as food antioxidants.
Silymarin is a well-known standardized extract from the seeds of milk thistle (Silybum marianum L., Asteraceae) with a pleiotropic effect on human health, including skin anticancer potential. Detailed characterization of flavonolignans properties affecting interactions with human skin was of interest. The partition coefficients log Pow of main constitutive flavonolignans, taxifolin and their respective dehydro derivatives were determined by a High Performance Liquid Chromatography (HPLC) method and by mathematical (in silico) approaches in n-octanol/water and model lipid membranes. These parameters were compared with human skin intake ex vivo. The experimental log Pow values for individual diastereomers were estimated for the first time. The replacement of n-octanol with model lipid membranes in the theoretical lipophilicity estimation improved the prediction strength. During transdermal transport, all the studied compounds permeated the human skin ex vivo; none of them reached the acceptor liquid. Both experimental/theoretical tools allowed the studied polyphenols to be divided into two groups: low (taxifolin, silychristin, silydianin) vs. high (silybin, dehydrosilybin, isosilybin) lipophilicity and skin intake. In silico predictions can be usefully applied for estimating general lipophilicity trends, such as skin penetration or accumulation predictions. However, the theoretical models cannot yet provide the dermal delivery differences of compounds with very similar physico-chemical properties; e.g., between diastereomers.
- MeSH
- hydrofobní a hydrofilní interakce MeSH
- lidé MeSH
- ostropestřec mariánský chemie MeSH
- permeabilita MeSH
- polyfenoly aplikace a dávkování chemie farmakologie MeSH
- škára účinky léků MeSH
- systémy cílené aplikace léků * MeSH
- termodynamika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Crops, such as white cabbage (Brassica oleracea L. var. capitata (L.) f. alba), are often infested by herbivorous insects that consume the leaves directly or lay eggs with subsequent injury by caterpillars. The plants can produce various defensive metabolites or free radicals that repel the insects to avert further damage. To study the production and effects of these compounds, large white cabbage butterflies, Pieris brassicae and flea beetles, Phyllotreta nemorum, were captured in a cabbage field and applied to plants cultivated in the lab. After insect infestation, leaves were collected and UV/Vis spectrophotometry and HPLC used to determine the content of stress molecules (superoxide), primary metabolites (amino acids), and secondary metabolites (phenolic acids and flavonoids). The highest level of superoxide was measured in plants exposed to fifty flea beetles. These plants also manifested a higher content of phenylalanine, a substrate for the synthesis of phenolic compounds, and in activation of total phenolics and flavonoid production. The levels of specific phenolic acids and flavonoids had higher variability when the dominant increase was in the flavonoid, quercetin. The leaves after flea beetle attack also showed an increase in ascorbic acid which is an important nutrient of cabbage.
Grape cane, leaves and grape marc are waste products from viticulture, which can be used to obtain secondary stilbene derivatives with high antioxidant value. The presented work compares several extraction methods: maceration at laboratory temperature, extraction at elevated temperature, fluidized-bed extraction, Soxhlet extraction, microwave-assisted extraction, and accelerated solvent extraction. To obtain trans-resveratrol, trans-ε-viniferin and r2-viniferin from grape cane of the V. vinifera variety Cabernet Moravia, various conditions were studied: different solvents, using powdered versus cut cane material, different extraction times, and one-step or multiple extractions. The largest concentrations found were 6030 ± 680 µg/g dry weight (d.w.) for trans-resveratrol, 2260 ± 90 µg/g d.w. for trans-ε-viniferin, and 510 ± 40 µg/g d.w. for r2-viniferin. The highest amounts of stilbenes (8500 ± 1100 µg/g d.w.) were obtained using accelerated solvent extraction in methanol.
- MeSH
- časové faktory MeSH
- chemická frakcionace metody MeSH
- hole * MeSH
- nukleární magnetická rezonance biomolekulární MeSH
- polyfenoly chemie izolace a purifikace MeSH
- rostlinné extrakty chemie izolace a purifikace MeSH
- rozpouštědla MeSH
- stilbeny chemie izolace a purifikace MeSH
- teplota MeSH
- Vitis chemie MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Polyphenols are known for their antimicrobial activity, whilst both polyphenols and the globular protein β-lactoglobulin (bLG) are suggested to have antioxidant properties and promote cell proliferation. These are potentially useful properties for a tissue-engineered construct, though it is unknown if they are retained when both compounds are used in combination. In this study, a range of different microbes and an osteoblast-like cell line (human fetal osteoblast, hFOB) were used to assess the combined effect of: (1) green tea extract (GTE), rich in the polyphenol epigallocatechin gallate (EGCG), and (2) whey protein isolate (WPI), rich in bLG. It was shown that approximately 20-48% of the EGCG in GTE reacted with WPI. GTE inhibited the growth of Gram-positive bacteria, an effect which was potentiated by the addition of WPI. GTE alone also significantly inhibited the growth of hFOB cells after 1, 4, and 7 days of culture. Alternatively, WPI significantly promoted hFOB cell growth in the absence of GTE and attenuated the effect of GTE at low concentrations (64 µg/mL) after 4 and 7 days. Low concentrations of WPI (50 µg/mL) also promoted the expression of the early osteogenic marker alkaline phosphatase (ALP) by hFOB cells, whereas GTE inhibited ALP activity. Therefore, the antioxidant effects of GTE can be boosted by WPI, but GTE is not suitable to be used as part of a tissue-engineered construct due to its cytotoxic effects which negate any positive effect WPI has on cell proliferation.
- MeSH
- antibakteriální látky chemie farmakologie MeSH
- antioxidancia chemie farmakologie MeSH
- Bacteria účinky léků MeSH
- buněčná diferenciace účinky léků MeSH
- buněčné linie MeSH
- čaj chemie MeSH
- dospělí MeSH
- fibroblasty cytologie účinky léků MeSH
- katechin analogy a deriváty chemie farmakologie MeSH
- kultivované buňky MeSH
- lidé MeSH
- mladý dospělý MeSH
- osteoblasty cytologie účinky léků MeSH
- osteogeneze účinky léků MeSH
- polyfenoly chemie farmakologie MeSH
- proliferace buněk účinky léků MeSH
- syrovátkové proteiny chemie farmakologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
