Káva je velmi oblíbený nápoj užívaný jako povzbuzující prostředek, ale také společensky při setkávání lidí či tradičně na závěr jídelního menu. Jedná se o vařený nápoj připravený z pražených semen kávovníku (Coffea). Kromě alkaloidu kofeinu obsahuje celou řadu jedinečných složek, které zodpovídají za rozličné zdravotní účinky. V sedmdesátých letech 20. století se začínala objevovat data o zvýšeném riziku onkologických a kardiovaskulárních onemocnění v souvislosti s konzumací kávy. Jedná se však o populační studie, v nichž pití kávy bylo spojováno s dalšími společenskými zvyklostmi (zejména kouření cigaret), a kauzalitu nebylo možno prokázat. Kvalitnější studie nového tisíciletí naopak ukazují na možné četné zdravotní benefity pití kávy. Zřejmě nejvyššího předpokladu zdravotní prospěšnosti lze dosáhnout konzumací tří až čtyř šálků tohoto nápoje. Takové množství kávy navíc neobsahuje dostatečné množství kofeinu na to, aby se mohl projevit signifikantní diuretický efekt.
Coffee is a very popular drink used as a stimulant, but also socially when meeting people or traditionally at the end of the eating menu. It is a brewed drink prepared from roasted seeds of a bush of the genus Coffea. In addition to the alkaloid caffeine, it contains a number of unique components that are responsible for various health effects. In the 1970s, data began to emerge on the increased risk of cancer and cardiovascular disease associated with coffee consumption. However, these were population-based studies in which coffee drinking was associated with other social behaviours (notably cigarette smoking) and causality could not be proven. In contrast, the better quality studies of the new millennium point to possible multiple health benefits of coffee drinking. Probably the highest assumption of health benefits can be achieved by consuming 3–4 cups of this beverage. Such a quantity of coffee does not contain sufficient caffeine to cause a significant diuretic effect.
- MeSH
- diabetes mellitus prevence a kontrola MeSH
- kardiovaskulární nemoci prevence a kontrola MeSH
- káva * chemie MeSH
- kofein farmakologie MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
- Klíčová slova
- zelená káva,
- MeSH
- káva * chemie MeSH
- klinické zkoušky jako téma MeSH
- kofein terapeutické užití MeSH
- kyselina chlorogenová * chemie MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
RATIONALE: The major objective of this exploratory study was to implement selected ion flow tube mass spectrometry, SIFT-MS, as a method for the on-line quantification of the volatile organic compounds, VOCs, in the headspace of the ground roasted coffee. METHODS: The optimal precursor ions and characteristic analyte ions were selected for real-time SIFT-MS quantification of those VOCs that are the most abundant in the headspace or known to contribute to aroma. NO+ reagent ion reactions were exploited for most of the VOC analyses. VOC identifications were confirmed using gas chromatography/mass spectrometry, GC/MS, coupled with solid-phase microextraction, SPME. RESULTS: Thirty-one VOCs were quantified, including several alcohols, aldehydes, ketones, carboxylic acids, esters and some heterocyclic compounds. Variations in the concentrations of each VOC in the seven regional coffees were typically less than a factor of 2, yet concentrations patterns characteristic of the different regional coffees were revealed by heat map and principal component analyses. The coefficient of variation in the concentrations across the seven coffees was typically below 24% except for furfural, furan, methylfuran and guaiacol. CONCLUSIONS: The SIFT-MS analytical method can be used to quantify in real time the most important odoriferous VOCs in ground coffee headspace to sufficient precision to reveal some differences in concentration patterns for coffee produced in different countries.
- MeSH
- aldehydy analýza MeSH
- alkoholy analýza MeSH
- analýza hlavních komponent MeSH
- analýza potravin metody MeSH
- Coffea chemie MeSH
- hmotnostní spektrometrie metody MeSH
- káva chemie MeSH
- ketony analýza MeSH
- manipulace s potravinami MeSH
- mikroextrakce na pevné fázi metody MeSH
- plynová chromatografie s hmotnostně spektrometrickou detekcí metody MeSH
- těkavé organické sloučeniny analýza chemie MeSH
- Publikační typ
- časopisecké články MeSH
This work investigates the potential bioconversion of spent coffee grounds (SCG) into lactic acid (LA). SCG were hydrolysed by a combination of dilute acid treatment and subsequent application of cellulase. The SCG hydrolysate contained a considerable amount of reducing sugars (9·02 ± 0·03 g l-1 , glucose; 26·49 ± 0·10 g l-1 galactose and 2·81 ± 0·07 g l-1 arabinose) and it was used as a substrate for culturing several lactic acid bacteria (LAB) and LA-producing Bacillus coagulans. Among the screened micro-organisms, Lactobacillus rhamnosus CCM 1825 was identified as the most promising producer of LA on a SCG hydrolysate. Despite the inhibitory effect exerted by furfural and phenolic compounds in the medium, reasonably high LA concentrations (25·69 ± 1·45 g l-1 ) and yields (98%) were gained. Therefore, it could be demonstrated that SCG is a promising raw material for the production of LA and could serve as a feedstock for the sustainable large-scale production of LA. SIGNIFICANCE AND IMPACT OF THE STUDY: Spent coffee grounds (SCG) represent solid waste generated in millions of tonnes by coffee-processing industries. Their disposal represents a serious environmental problem; however, SCG could be valorized within a biorefinery concept yielding various valuable products. Herein, we suggest that SCG can be used as a complex carbon source for the lactic acid production.
- MeSH
- Bacillus coagulans enzymologie metabolismus MeSH
- bioreaktory mikrobiologie MeSH
- biotechnologie MeSH
- celulasa metabolismus MeSH
- fermentace MeSH
- hydrolýza MeSH
- káva chemie metabolismus MeSH
- kyselina mléčná biosyntéza MeSH
- Lacticaseibacillus rhamnosus enzymologie metabolismus MeSH
- odpadky - odstraňování metody MeSH
- tuhý odpad MeSH
- Publikační typ
- časopisecké články MeSH
The presented work describes the development and validation of a rapid UHPLC-UV method using a fused core particle column with an RP-Amide stationary phase for the separation and quantitative analysis of caffeoylquinic and di-caffeoylquinic acids in green coffee extracts. Three caffeoylquinic acids (3-caffeoylquinic acid, 4-caffeoylquinic acid, and 5-caffeoylquinic acid) and two di-caffeoylquinic acids (1,3-di-caffeoylquinic acid, and 3,5-di-caffeoylquinic acid) were separated and analyzed in 8 min. That was possible due to the unique selectivity of the RP-Amide stationary phase for the analyzed acids. The retention behavior of all analytes under different compositions of the mobile phase on different columns was evaluated in this study. The optimal chromatographic separation was performed using an Ascentis Express RP-Amide (100 × 2.1 mm) fused-core column with a particle size of 2.7 μm at a temperature of 30 °C. For validation of the newly developed method, acetonitrile was used as mobile phase B and 5% formic acid, filtrated through a 0.22 μm filter, was used as mobile phase A. They were delivered at a flow rate of 0.9 mL min-1 according to the elution gradient program. The detection wavelength was set at 325 nm. A solid-liquid extraction with a solution of methanol and a 5% water solution of formic acid (25 + 75 v/v) using an ultrasonic bath was chosen for the preparation of the available commercial samples of food supplements containing a green coffee extract. Recoveries for all analyzed acids were 98.2-101.0% and the relative standard deviation ranged from 0.3% to 1.4% for intra-day and from 0.3% to 3.0% for inter-day repeatability. The limits of detection were in the range of 0.30-0.53 μg mL-1.
- MeSH
- acetonitrily chemie MeSH
- amidy chemie MeSH
- časové faktory MeSH
- extrakce kapalina-kapalina přístrojové vybavení metody MeSH
- farmaceutická chemie přístrojové vybavení metody MeSH
- káva chemie MeSH
- kyselina chinová analogy a deriváty analýza MeSH
- limita detekce MeSH
- poréznost MeSH
- rostlinné extrakty analýza chemie MeSH
- vysokoúčinná kapalinová chromatografie přístrojové vybavení metody MeSH
- Publikační typ
- časopisecké články MeSH
- validační studie MeSH
A novel fully automated in-vitro oral dissolution test assay as a front-end to liquid chromatography has been developed and validated for on-line chemical profiling and monitoring of temporal release profiles of three caffeoylquinic acid (CQA) isomers, namely, 3-CQA,4-CQA and 5-CQA, known as chlorogenic acids, in dietary supplements. Tangential-flow filtration is harnessed as a sample processing approach for on-line handling of CQA containing extracts of hard gelatin capsules and introduction of protein-free samples into the liquid chromatograph. Oral bioaccessibility/dissolution test assays were performed at 37.0±0.5°C as per US Pharmacopeia recommendations using pepsin with activity of ca. 749,000 USP units/L in 0.1mol/L HCl as the extraction medium and a paddle apparatus stirred at 50rpm. CQA release rates and steady-state dissolution conditions were determined accurately by fitting the chromatographic datasets, namely, the average cumulative concentrations of bioaccessible pools of every individual isomer monitored during 200min, with temporal resolutions of ≥10min, to a first-order dissolution kinetic model. Distinct solid-to-liquid phase ratios in the mimicry of physiological extraction conditions were assessed. Relative standard deviations for intra-day repeatability and inter-day intermediate precision of 5-CQA within the 5-40µg/mL concentration range were <3.4% and <5.5%, respectively. Trueness of the automatic flow method for determination of 5-CQA released from dietary supplements in gastric fluid surrogate was demonstrated by spike recoveries, spanning from 91.5-104.0%, upon completion of the dissolution process. The proposed hyphenated setup was resorted for evaluating potential differences in dissolution profiles and content of the three most abundant chlorogenic acid isomers in dietary supplements from varied manufacturers.
- MeSH
- aplikace orální MeSH
- biologická dostupnost MeSH
- chromatografie kapalinová metody MeSH
- isomerie MeSH
- káva chemie MeSH
- kyselina chlorogenová aplikace a dávkování analýza farmakokinetika MeSH
- limita detekce MeSH
- on-line systémy MeSH
- potravní doplňky analýza MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- antioxidancia fyziologie MeSH
- káva * chemie imunologie MeSH
- leukocyty účinky léků MeSH
- lidé MeSH
- poškození DNA účinky léků MeSH
- reishi MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- zprávy MeSH
- MeSH
- antioxidancia fyziologie MeSH
- káva * chemie imunologie MeSH
- leukocyty účinky léků MeSH
- lidé MeSH
- poškození DNA účinky léků MeSH
- reishi MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- zprávy MeSH
Caffeine is a most widely consumed physiological stimulant worldwide, which is consumed via natural sources, such as coffee and tea, and now marketed sources such as energy drinks and other dietary supplements. This wide use has led to concerns regarding the safety of caffeine and its proposed beneficial role in alertness, performance and energy expenditure and side effects in the cardiovascular system. The question remains "Which dose is safe?", as the population does not appear to adhere to the strict guidelines listed on caffeine consumption. Studies in humans and animal models yield controversial results, which can be explained by population, type and dose of caffeine and low statistical power. This review will focus on comprehensive and critical review of the current literature and provide an avenue for further study.
- MeSH
- cévy účinky léků metabolismus MeSH
- kardiovaskulární nemoci epidemiologie MeSH
- káva škodlivé účinky chemie MeSH
- klinická studie jako téma MeSH
- kofein aplikace a dávkování škodlivé účinky MeSH
- lidé MeSH
- metaanalýza jako téma MeSH
- metabolický syndrom epidemiologie MeSH
- modely nemocí na zvířatech MeSH
- srdce účinky léků fyziologie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
