Phytochemical and nutritional compositions and antioxidants properties of wild edible flowers as sources of new tea formulations

Quick and Green Microextraction of Pyrrolizidine Alkaloids from Infusions of Mallow, Calendula, and Hibiscus Flowers Using Ultrahigh-Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry Analysis

A sustainable microextraction of pyrrolizidine alkaloids (PAs) from edible flower infusions using the innovative μSPEed technique is proposed. Different sorbents and extraction conditions were tested, achieving the highest extraction efficiency with an octadecylsilane sorbent (4 mg). The extraction procedure just took 1 min per sample, and only 300 μL of methanol and 300 μL of the sample were used per extraction. Ultrahigh-performance liquid chromatography coupled to tandem mass spectrometry was used for analysis. The method was properly validated, providing suitable linearity, selectivity, sensitivity (quantification limits 0.3-1 μg/L), overall recoveries (79-97%), and precision (≤17% relative standard deviation). Its application to the analysis of different infusions of mallow, calendula, and hibiscus flowers revealed similar total PA values (23-41 μg/L) and contamination profile among the mallow and hibiscus samples, with predominance of senecionine-type and heliotrine-type PAs, respectively. Conversely, calendula samples showed more variations (23-113 μg/L), highlighting the occurrence of intermedine N-oxide and europine N-oxide on them.

Edible Flowers as a Source of Dietary Fibre (Total, Insoluble and Soluble) as a Potential Athlete's Dietary Supplement

Edible flowers have been gaining popularity among researchers, nutritionists and chefs all around the world. Nowadays, flowers are used to make food look and/or taste better; however, they are also a very good source of valuable nutrients (antioxidants, vitamins, proteins, fats, carbohydrates, macro and microelements). The aim of our study was to determine the content of dietary fibre and total protein in selected edible flowers; we also compared the nutritional content of petals, differentiating between the representatives of the Oleaceae and Asteraceae families, as well as herbaceous vs. woody plants. The study material consisted of petals of 12 edible flower species (Magnolia × soulangeana, Sambucus nigra L., Syringa vulgaris L. (white and violet flowers), Robinia pseudoacacia, Forsythia × intermedia, Cichorium intybus L., Bellis perennis, Tussilago farfara L., Taraxacum officinale F.H. Wiggers coll., Centaurea cyanus L., Calendula officinalis). Dietary fibre content was determined by the enzymatic-gravimetric method and ranged from 13.22 (Magnolia × soulangeana) to 62.33 (Calendula officinalis L.) g/100 g. For insoluble dietary fibre (IDF), the values ranged from 8.69 (Magnolia × soulangeana) to 57.54 (Calendula officinalis L.) g/100 g, and the content of soluble dietary fibre (SDF) was between 1.35 (Syringa vulgaris L.-white flowers) and 7.46 (Centaurea cyanus L) g/100 g. Flowers were also shown to be a good, though underappreciated, source of plant protein, with content ranging from 8.70 (Calendula officinalis L.) to 21.61 (Magnolia × soulangeana) g/100 g dry matter (Kjeldahl method). Considerable amounts of protein were found in the flowers of the olive family (Oleaceae) and woody plants, which can enrich the daily diet, especially vegan and vegetarian. Edible flowers of the Asteraceae family, especially the herbaceous representatives, contained high levels of both total dietary fibre and its insoluble fraction; therefore, they can be a rich source of these nutrients in the daily diet of athletes, which would perform a prebiotic function for gut bacteria.

Production of Non-Volatile Metabolites from Sooty Molds and Their Bio-Functionalities

In the current study, eleven sooty mold isolates were collected from different tropical host plants. The isolates were identified under Capnodium, Leptoxyphium and Trichomerium, based on morphology and phylogeny. For the secondary metabolite analysis, the isolates were grown on Potato Dextrose Broth (PDB). The well-grown mycelia were filtered and extracted over methanol (MeOH). The metabolites in the growth medium (or filtrate) were extracted over ethyl acetate (EtOAc). The antifungal activities of each crude extract were tested over Alternaria sp., Colletotrichum sp., Curvularia sp., Fusarium sp. and Pestalotiopsis sp. The metabolites were further tested for their total phenolic, flavonoid and protein content prior to their antioxidant and anti-fungal potential evaluation. The MeOH extracts of sooty molds were enriched with proteins and specifically inhibited Curvularia sp. The total phenolic content and 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) activity was largely recovered from the filtrate corresponding to the inhibition of Alternaria sp.; while the flavonoid and free radical reduction suggested a relative induction of growth of the Fusarium sp., Colletotrichum sp. and Pestalotiopsis sp. Hence, this study reveals the diversity of sooty molds in Thailand by a modern phylogenetic approach. Furthermore, the preliminary screening of the isolates reveals the potential of finding novel compounds and providing insights for the future research on secondary metabolites of bio-trophic fungi and their potential usage on sustainable agriculture.

The Compositional Aspects of Edible Flowers as an Emerging Horticultural Product

Edible flowers are becoming very popular, as consumers are seeking healthier and more attractive food products that can improve their diet aesthetics and diversify their dietary sources of micronutrients. The great variety of flowers that can be eaten is also associated with high variability in chemical composition, especially in bioactive compounds content that may significantly contribute to human health. The advanced analytical techniques allowed us to reveal the chemical composition of edible flowers and identify new compounds and effects that were not known until recently. Considering the numerous species of edible flowers, the present review aims to categorize the various species depending on their chemical composition and also to present the main groups of compounds that are usually present in the species that are most commonly used for culinary purposes. Moreover, special attention is given to those species that contain potentially toxic or poisonous compounds as their integration in human diets should be carefully considered. In conclusion, the present review provides useful information regarding the chemical composition and the main groups of chemical compounds that are present in the flowers of the most common species.

Recovery of Polyphenolic Fraction from Arabica Coffee Pulp and Its Antifungal Applications

Coffee pulp is one of the most underutilised by-products from coffee processing. For coffee growers, disposing of this agro-industrial biomass has become one of the most difficult challenges. This study utilised this potential biomass as raw material for polyphenolic antifungal agents. First, the proportion of biomass was obtained from the Arabica green bean processing. The yield of by-products was recorded, and the high-potency biomass was serially extracted with organic solvents for the polyphenol fraction. Quantification of the polyphenols was performed by High Performance Liquid Chromatography (HPLC), then further confirmed by mass spectrometry modes of the liquid chromatography–quadrupole time-of-flight (QTOF). Then, the fraction was used to test antifungal activities against Alternaria brassicicola, Pestalotiopsis sp. and Paramyrothecium breviseta. The results illustrated that caffeic acid and epigallocatechin gallate represented in the polyphenol fraction actively inhibited these fungi with an inhibitory concentration (IC50) of 0.09, 0.31 and 0.14, respectively. This study is also the first report on the alternative use of natural biocontrol agent of P. breviseta, the pathogen causing leaf spot in the Arabica coffee.