Throughout most of history, medicinal plants and their active metabolites have represented a valuable source of compounds used to prevent and to cure several diseases. Interest in natural compounds ...is still high as they represent a source of novel biologically/pharmacologically active compounds. Due to their high structural diversity and complexity, they are interesting structural scaffolds that can offer promising candidates for the study of new drugs, functional foods, and food additives.
Plant extracts are a highly complex mixture of compounds and qualitative and quantitative analyses are necessary to ensure their quality. Furthermore, greener methods of extraction and analysis are needed today.
This book is based on articles submitted for publication in the Special Issue entitled “Qualitative and Quantitative Analysis of Bioactive Natural Products” that collected original research and reviews on these topics.
•Novel 2D-LC method for the analysis of oligonucleotides.•Optimised size and sequence based HPLC oligonucleotides separations.•Orthogonal workflow was developed using IP RP HPLC coupled with SAX ...HPLC.•2D-LC resulted in increased peak capacity, a reduction in co-elution events and improved resolution.
Oligonucleotides are commonly analysed using one dimensional chromatography (1D-LC) to resolve and characterise manufacturing impurities, structural isomers and (in respect to emerging oligonucleotide therapeutics) drug substance and drug product. Due to low selectivity and co-elution of closely related oligonucleotides using 1D-LC, analyte resolution is challenged. This leads to the requirement for improved analytical methods. Multidimensional chromatography has demonstrated utility in a range of applications as it increases peak capacity using orthogonal separations, however there are limited studies demonstrating the 2D-LC analysis of closely related oligonucleotides. In this study we optimised OGN size and sequence based separations using a variety of 1D-LC methods and coupled these orthogonal modes of chromatography within a 2D-LC workflow. Theoretical 2D-LC workflows were evaluated for optimal orthogonality using the minimum convex hull metric. The most orthogonal workflow identified in this study was ion-pair reversed phase using tributylammonium acetate (IP-RP-TBuAA) coupled with strong anion exchange in conjunction with sodium perchlorate (SAX-NaClO4) at high mobile phase pH. We developed a heart-cut (IP-RP-TBuAA)-(SAX-NaClO4) 2D-LC method for analysis of closely related size and sequence variant OGNs and OGN manufacturing impurities. The 2D-LC method resulted in an increased orthogonality and a reduction in co-elution (or close elution). Application of a UV based reference mapping strategy in conjunction with the 2D-LC method demonstrated a reduction in analytical complexity by reducing the reliance on mass based detection methods.
Sustainable Development Goal 12 and target 12.3 set by the United Nations aims to reduce”food waste” per capita global for 50% losses by 2030. Databases such as the PhInd could help us to achieve set ...goals via mapping the potential ways for valorization of polyphenols from the agri-food by-products and waste. Fruit by-products (73.2% of the PhInd entries) are the most studied sources of polyphenols and future studies might be more focused on vegetables. More than half (55.8%) of entries were evaluated polyphenols in samples created in laboratory. These samples could have significantly different composition from industrial samples. Solid-liquid extraction (53.5%) and solvents like water, ethanol and aqueous ethanol (51.5%) were the most often used for extraction of polyphenols. Green solvents as NADES (0.4%) are rarely used in studies and should be more explored.
•Fruit by-products and waste are 73.2% of PhInd entries•Data for waste from other plant classes (vegetables, nut, cereals) are lacking•Samples from industrial setting should be used more (44% entries) for valorization•Extraction of polyphenols with NADES (only 0.4%) needs further elaboration
•A fast method for the simultaneous determination of 11 additives.•HPLC coupled with DAD and MS/MS methods are used.•Good recoveries in the range of 75.2–113.8%.•Suitable for the routine monitoring ...analysis of 11 additives.
In this study, an efficient, fast and sensitive method for the simultaneous determination of eleven synthetic color additives (Allura red, Amaranth, Azo rubine, Brilliant blue, Erythrosine, Indigotine, Ponceau 4R, New red, Sunset yellow, Quinoline yellow and Tartrazine) in flour and meat foodstuffs is developed and validated using HPLC coupled with DAD and MS/MS. The color additives were extracted with ammonia–methanol and was further purified with SPE procedure using Strata-AW column in order to reduce matrix interference. This HPLC–DAD method is intended for a comprehensive survey of color additives in foods. HPLC–MS/MS method was used as the further confirmation and identification. Validation data showed the good recoveries in the range of 75.2–113.8%, with relative standard deviations less than 15%. These methods are suitable for the routine monitoring analysis of eleven synthetic color additives due to its sensitivity, reasonable time and cost.
•Easy, fast and inexpensive sample preparation method for phenolic compounds analysis in honey.•Accurate and sensitive quantification by HPLC–UV and unambiguous determination by HPLC–HRMS.•Extraction ...efficiency comparable to the conventional method.•Suitable technique for the analysis of other honey phytochemicals.
Honey is a valuable functional food rich in phenolic compounds with a broad spectrum of biological activities. Analysis of the phenolic compounds in honey is a very promising tool for the quality control, the authentication and characterization of botanical origin, and the nutraceutical research. This work describes a novel approach for the rapid analysis of five phenolic acids and 10 flavonoids in honey. Phenolic compounds were rapidly extracted and concentrated from diluted honey by dispersive liquid–liquid microextraction (DLLME) and then analyzed using high performance liquid chromatography with UV absorbance detection (HPLC–UV). Some important parameters, such as the nature and volume of extraction and dispersive solvents, pH and salt effect were carefully investigated and optimized to achieve the best extraction efficiency. Under the optimal conditions, an exhaustive extraction for twelve of the investigated analytes (recoveries >70%), with a precision (RSD<10%) highly acceptable for complex matrices, and detection and quantification limits at ppb levels (1.4–12 and 4.7–40ngg−1, respectively) were attained. The proposed method, compared with the most widely used method in the analysis of phenolic compounds in honey, provided similar or higher extraction efficiency, except in the case of the most hydrophilic phenolic acids. The capability of DLLME to the extraction of other honey phytochemicals, such as abscisic acid, was also demonstrated. The main advantages of developed method are the simplicity of operation, the rapidity to achieve a very high sample throughput and low cost.
•Sample preparation techniques coupled with high-performance liquid chromatography and a suitable detector.•Combining sample preparation techniques to achieve satisfactory extraction efficiency, ...cleanup as well as excellent preconcentration capacity.•Validating an analytical method to ensure the quality and reliability of any data produced is a fundamental step in any measurement's life-cycle.•Sample preparation techniques future.
This review article compares and contrasts sample preparation techniques coupled with high-performance liquid chromatography (HPLC) and describes applications developed in biomedical, forensics, and environmental/industrial hygiene in the last two decades. The proper sample preparation technique can offer valued data for a targeted application when coupled to HPLC and a suitable detector. Improvements in sample preparation techniques in the last two decades have resulted in efficient extraction, cleanup, and preconcentration in a single step, thus providing a pathway to tackle complex matrix applications. Applications such as biological therapeutics, proteomics, lipidomics, metabolomics, environmental/industrial hygiene, forensics, glycan cleanup, etc., have been significantly enhanced due to improved sample preparation techniques. This review looks at the early sample preparation techniques. Further, it describes eight sample preparation technique coupled to HPLC that has gained prominence in the last two decades. They are (1) solid-phase extraction (SPE), (2) liquid-liquid extraction (LLE), (3) gel permeation chromatography (GPC), (4) Quick Easy Cheap Effective Rugged, Safe (QuEChERS), (5) solid-phase microextraction (SPME), (6) ultrasonic-assisted solvent extraction (UASE), and (7) microwave-assisted solvent extraction (MWASE). SPE, LLE, GPC, QuEChERS, and SPME can be used offline and online with HPLC. UASE and MWASE can be used offline with HPLC but have also been combined with the online automated techniques of SPE, LLE, GPC, or QuEChERS for targeted analysis. Three application areas of biomedical, forensics, and environmental/industrial hygiene are reviewed for the eight sample preparation techniques. Three hundred and twenty references on the eight sample preparation techniques published over the last two decades (2001–2021) are provided. Other older references were included to illustrate the historical development of sample preparation techniques.
•Authenticity control of high priced argan oils is most important.•We developed a simple and rapid HPLC–ELSD method to identify adulterations of argan oil.•The triacylglycerol patterns selectively ...and sensitively disclose adulterations.
Triacylglycerol profiles were selected as indicator of adulteration of argan oils to carry out a rapid screening of samples for the evaluation of authenticity. Triacylglycerols were separated by high-performance liquid chromatography–evaporative light scattering detection. Different peak area ratios were defined to sensitively detect adulteration of argan oil with vegetable oils such as sunflower, soy bean, and olive oil up to the level of 5%. Based on four reference argan oils, mean limits of detection and quantitation were calculated to approximately 0.4% and 1.3%, respectively. Additionally, 19 more argan oil reference samples were analysed by high-performance liquid chromatography–refractive index detection, resulting in highly comparative results. The overall strategy demonstrated a good applicability in practise, and hence a high potential to be transferred to routine laboratories.
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•TLC and HPLC–QTOF/MS techniques were employed to compare the chemical profiles of CWT and CML.•A HPLC–DAD method was developed for quantification of eight major compounds in CWT and ...CML.•The antioxidant activity of CWT and CML were compared by DPPH, FRAP and ABTS assay.•The results indicated that there were significant chemical differences between CWT and CML, and CWT had higher antioxidant activity than CML.
Citri Fructus (CF), the mature fruit of Citrus wilsonii Tanaka (CWT) or Citrus medica L. (CML), is an important citrus by-product with health promoting and nutritive properties. The present study compares the chemical and biological differences of CWT and CML. Thin layer chromatography and high performance liquid chromatography, coupled with quadrupole time-of-flight tandem mass spectrometry techniques, were employed to compare the chemical profiles of CWT and CML. A total of 25 compounds were identified and the results indicated that there were significant differences in chemical composition between the two CF species. The quantitative results obtained by HPLC coupled with diode array detector method demonstrated that naringin was present in the highest amounts in CWT, whilst nomilin was the most dominant constituent in CML. It was also found that CWT had significantly higher free radical-scavenging activity than CML.
