Concept of a six-fold multiplex planar bioassay to distinguish endocrine agonist, antagonist, cytotoxic and false-positive responses

To analyze a complex sample for endocrine activity, different tests must be performed to clarify androgen/estrogen agonism, antagonism, cytotoxicity, anti-cytotoxicity, and corresponding false-positive reactions. This means a large amount of work. Therefore, a six-fold planar multiplex bioassay concept was developed to evaluate up to the mentioned six endpoints or mechanisms simultaneously in the same sample analysis. Separation of active constituents from interfering matrix via high-performance thin-layer chromatography and effect differentiation via four vertical stripes (of agonists and end-products of the respective enzyme-substrate reaction) applied along each separated sample track were key to success. First, duplex endocrine bioassay versions were established. For the androgen/anti-androgen bioassay applied via piezoelectric spraying, the mean limit of biological detection of bisphenol A was 14 ng/band and its mean half maximal inhibitory concentration IC50 was 116 ng/band. Applied to trace analysis of six migrate samples from food packaging materials, 19 compound zones with agonistic or antagonistic estrogen/androgen activities were detected, with up to seven active compound zones within one migrate. For the first time, the S9 metabolism of endocrine effective compounds was studied on the same surface and revealed partial deactivation. Coupled to high-resolution mass spectrometry, molecular formulas were tentatively assigned to compounds, known to be present in packaging materials or endocrine active or previously unknown. Finally, the detection of cytotoxicity/anti-cytotoxicity and false-positives was integrated into the duplex androgen/anti-androgen bioassay. The resulting six-fold multiplex planar bioassay was evaluated with positive control standards and successfully applied to one migrate sample. The streamlined stripe concept for multiplex planar bioassays made it possible to assign different mechanisms to individual active compounds in a complex sample. The concept is generic and can be transferred to other assays.

A Novel Approach about Edible Packaging Materials Based on Oilcakes-A Review

Due to the growing global population and subsequent environment degradation, as well as changes in the climate, changing consumers' dietary habits is necessary to create strategies for the most efficient use of natural resources to eliminate waste in the food supply chain. The packaging of food is essential to preserve the food's properties, extend its shelf life and offer nutritional information. Food products are packaged in various materials of which the most used are plastics, but they have a negative impact on the environment. Various efforts have been made to address this situation, but unfortunately, this includes recycling rather than replacing them with sustainable solutions. There is a trend toward edible packaging materials with more additional functions (antioxidant, antimicrobial and nutritional properties). Edible packaging is also a sustainable solution to avoid food waste and environment pollution. Oilcakes are the principal by-products obtained from the oil extraction process. These by-products are currently underused as animal feed, landfilling or compost. Because they contain large amounts of valuable compounds and are low-cost ingredients, they can be used to produce materials suitable for food packaging. This review covers the recent developments in oilcake-based packaging materials. Special emphasis is placed on the study of materials and technologies that can be used to make edible film in order to research the most suitable ways of developing oilcake-based film that can be consumed simultaneously with the product. These types of materials do not exist on the market.

Effect-Directed Profiling of Monofloral Honeys from Ethiopia by High-Performance Thin-Layer Chromatography and High-Resolution Mass Spectrometry

Ethiopian honey is used not only as food but also for treatment in traditional medicine. For its valorization, bioactive compounds were analyzed in nine types of monofloral Ethiopian honey. Therefore, a non-target effect-directed profiling was developed via high-performance thin-layer chromatography combined with multi-imaging and planar effect-directed assays. Characteristic bioactivity profiles of the different honeys were determined in terms of antibacterial, free-radical scavenging, and various enzyme inhibitory activities. Honeys from Hypoestes spp. and Leucas abyssinica showed low activity in all assays. In contrast, others from Acacia spp., Becium grandiflorum, Croton macrostachyus, Eucalyptus globulus, Schefflera abyssinica, Vernonia amygdalina, and Coffea arabica showed more intense activity profiles, but these differed depending on the assay. In particular, the radical scavenging activity of Croton macrostachyus and Coffea arabica honeys, the acetylcholinesterase-inhibiting activity of Eucalyptus globulus and Coffea arabica honeys, and the antibacterial activity of Schefflera abyssinica honey are highlighted. Bioactive compounds of interest were further characterized by high-resolution mass spectrometry. Identifying differences in bioactivity between mono-floral honey types affects quality designation and branding. Effect-directed profiling provides new insights that are valuable for food science and nutrition as well as for the market, and contributes to honey differentiation, categorization, and authentication.

Puree and Juice of Thai Mango and Pineapple Analyzed by High-Performance Thin-Layer Chromatography Hyphenated with Effect-Directed Assays

The requirements for analytical tools are changing due to the global production chain, the increasing cases of adulteration, and the growing trend towards consumption of plant-based food products worldwide. The assessment of bioactivity of natural foods is currently not a quality criterion, and a paradigm shift is postulated. A non-targeted effect-directed profiling by high-performance thin-layer chromatography hyphenated with five different effect-directed assays was developed exemplarily for the puree and juice products of mango Mangifera indica L. (Anacardiaceae) and pineapple Ananas comosus (L.) Merr. (Bromeliaceae). Several bioactive compounds were detected in each sample. The additional bioactivity information obtained through effect-directed profiles improves, expands and modernizes product control. Non-target effect-directed profiling adds a new perspective to previous target analysis results that can be used not only to ensure health claims based on bioactive compounds, but also to detect unknown bioactive compounds coming from contamination or residues or changes caused by food processing.

Effect-directed profiling of Ficus religiosa leaf extracts for multipotent compounds via 12 effect-directed assays

The interest in the therapeutic values of natural compounds from plants is growing worldwide because the development of modern synthetic drugs has not lived up to expectations. The tree Ficus religiosa native to India, China and Southeast Asia is traditionally used for curing almost 50 ailments, although the majority of the individual active compounds are not known. Hence, a hyphenated high-performance thin-layer chromatography (HPTLC) method was newly developed. It allowed a physicochemical, but especially effect-directed profiling of individual compounds present in Ficus religiosa leaves obtained from four locations (in India and Germany). Extracts of different polarities were screened for bioactivity responses and most bioactivities were found in the ethyl acetate extracts. A multi-imaging via 26 different detection modes was performed, i. e. UV/Vis/FLD, 11 microchemical derivatizations and 12 effect-directed assays (EDA). By HPTLC-UV/Vis/FLD-EDA, antibiotics against Gram-positive and Gram-negative bacteria as well as acetylcholinesterase, butyrylcholinesterase, tyrosinase, α-amylase, α-glucosidase and β-glucosidase inhibitors and radical scavenging compounds were detected. Estrogen-like or gentotoxic compounds were not detected at higher extract amounts of even 5 mg/band applied. For further characterization of three most important, multipotent, bioactive compound zones, HPTLC was hyphenated with heated electrospray ionization high-resolution mass spectrometry including fragmentation (HPTLC-HESI-HRMS/MS). Multipotent bioactive compounds discovered in the extracts were equivalently calculated in reference to well-known reference inhibitors.

Emerging challenges in the extraction, analysis and bioanalysis of cannabidiol and related compounds

Cannabidiol (CBD) is a bioactive terpenophenolic compound isolated from Cannabis sativa L. It is known to possess several properties of pharmaceutical interest, such as antioxidant, anti-inflammatory, anti-microbial, neuroprotective and anti-convulsant, being it active as a multi-target compound. From a therapeutic point of view, CBD is most commonly used for seizure disorder in children. CBD is present in both medical and fiber-type C. sativa plants, but, unlike Δ⁹-tetrahydrocannabinol (THC), it is a non-psychoactive compound. Non-psychoactive or fiber-type C. sativa (also known as hemp) differs from the medical one, since it contains only low levels of THC and high levels of CBD and related non-psychoactive cannabinoids. In addition to medical Cannabis, which is used for many different therapeutic purposes, a great expansion of the market of hemp plant material and related products has been observed in recent years, due to its usage in many fields, including food, cosmetics and electronic cigarettes liquids (commonly known as e-liquids). In this view, this work is focused on recent advances on sample preparation strategies and analytical methods for the chemical analysis of CBD and related compounds in both C. sativa plant material, its derived products and biological samples. Since sample preparation is considered to be a crucial step in the development of reliable analytical methods for the determination of natural compounds in complex matrices, different extraction methods are discussed. As regards the analysis of CBD and related compounds, the application of both separation and non-separation methods is discussed in detail. The advantages, disadvantages and applicability of the different methodologies currently available are evaluated. The scientific interest in the development of portable devices for the reliable analysis of CBD in vegetable and biological samples is also highlighted.

HPTLC-aptastaining - Innovative protein detection system for high-performance thin-layer chromatography

Protein analysis using high-performance thin-layer chromatography (HPTLC) is not commonly used but can complement traditional electrophoretic and mass spectrometric approaches in a unique way. Due to various detection protocols and possibilities for hyphenation, HPTLC protein analysis is a promising alternative for e.g., investigating posttranslational modifications. This study exemplarily focused on the investigation of lysozyme, an enzyme which is occurring in eggs and technologically added to foods and beverages such as wine. The detection of lysozyme is mandatory, as it might trigger allergenic reactions in sensitive individuals. To underline the advantages of HPTLC in protein analysis, the development of innovative, highly specific staining protocols leads to improved sensitivity for protein detection on HPTLC plates in comparison to universal protein derivatization reagents. This study aimed at developing a detection methodology for HPTLC separated proteins using aptamers. Due to their affinity and specificity towards a wide range of targets, an aptamer based staining procedure on HPTLC (HPTLC-aptastaining) will enable manifold analytical possibilities. Besides the proof of its applicability for the very first time, (i) aptamer-based staining of proteins is applicable on different stationary phase materials and (ii) furthermore, it can be used as an approach for a semi-quantitative estimation of protein concentrations.