Edible flowers, a source of valuable phytonutrients and their pro-healthy effects – A review

Evaluation of the physical, antioxidant, and organoleptic properties of biscuits fortified with edible flower powders

Foods enriched with plants have gradually become an area of increasing research interest because plant ingredients may offer several positive effects on human health and the body. The aim of our study was to develop biscuits fortified with three different types of edible flowers (marigold, lavender, and rose) and examine their physical and antioxidant characteristics, as well as consumer acceptability. The antioxidant properties and characterization of biscuits highlighted that edible flowers may cause increased total polyphenol and total flavonoid yields, as well as DPPH radical scavenging activities. Concerning biscuits fortified with rose petals, the total monomer anthocyanin content was also raised. In addition, the results showed that the antioxidant properties of biscuits increased with increasing concentration (from 2.5% to 5.0%) of edible flowers. Despite this, the consumer acceptability results clearly showed that the addition of marigold and lavender at a concentration of 5.0% caused significantly decreased overall acceptance. We found that the fortification step may increase the spread ratio, which is an important quality attribute of biscuits. We found slight variations in the diameter, thickness, and baking loss parameters of fortified biscuits compared to the control. All in all, the best results were obtained when the biscuits were fortified with rose petals at a concentration of 5%.

Alternative Assisted Extraction Methods of Phenolic Compounds Using NaDESs

A renewed understanding of eco-friendly principles is moving the industrial sector toward a shift in the utilization of less harmful solvents as a main strategy to improve manufacturing. Green analytical chemistry (GAC) has definitely paved the way for this transition by presenting green solvents to a larger audience. Among the most promising, surely DESs (deep eutectic solvents), NaDESs (natural deep eutectic solvents), HDESs (hydrophobic deep eutectic solvents), and HNaDESs (hydrophobic natural deep eutectic solvents), with their unique features, manifest a wide-range of applications, including their use as a means for the extraction of small bioactive compounds. In examining recent advancements, in this review, we want to focus our attention on some of the most interesting and novel 'solvent-free' extraction techniques, such as microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) in relation to the possibility of better exploiting DESs and NaDESs as plausible extracting solvents of the phenolic compounds (PCs) present in different matrices from olive oil components, such as virgin olive pomace, olive leaves and twigs, virgin and extra virgin olive oil (VOO and EVOO, respectively), and olive cake and olive mill wastewaters (OMWW). Therefore, the status of DESs and NaDESs is shown in terms of their nature, efficacy and selectivity in the extraction of bioactive phytochemicals such as secoiridoids, lignans, phenolic acids and alcohols. Related studies on experimental design and processes' optimization of the most promising DESs/NaDESs are also reviewed. In this framework, an extensive list of relevant works found in the literature is described to consider DESs/NaDESs as a suitable alternative to petrochemicals in cosmetics, pharmaceutical, or food applications.

Ethnobotanical study on edible flowers in Xishuangbanna, China

BACKGROUND

Edible flowers (EFs) represent valuable sources of both food and medicinal resources, holding the promise to enhance human well-being. Unfortunately, their significance is often overlooked. Ethnobotanical studies on the EFs are lacking in comparison with their botanical and phytochemical research. The practice of consuming flowers as food has a rich culture and long history in China, especially among different linguistic groups in Xishuangbanna, Yunnan. However, economic activities have led to a decline of this tradition. Consequently, preserving the traditional knowledge and culture tied to the EFs in Xishuangbanna becomes both essential and pressing.

METHODS

The field ethnobotanical survey was conducted in Xishuangbanna during five visits in April 2021 and May 2023, covering 48 villages and 19 local markets of all three county-level areas and 9 different linguistic groups. By conducting a comprehensive literature review and on-site field surveys, relevant information regarding the EFs of Xishuangbanna was systematically collected and documented. Additionally, the relative frequency of citation (RFC) values were calculated from the survey data.

RESULTS

A total of 212 taxa (including species and varieties) of EFs from 58 families and 141 genera were documented in the study area. The edible parts of flowers were classified into 13 categories including peduncle, petal, flower buds, inflorescence as a whole, and etc. They were consumed in 21 ways and as 8 types of food. The inflorescence was the most commonly consumed category, accounting for 85 species (40.1%) of the total categories. They always eat flowers as vegetables (184 species, 86.8%). The preparing form of stir-frying was the preferred food preparation method (138, 65.1%). The Xishuangbanna locals had profound knowledge of which EFs required specific processing to remove their toxicity or bitterness. The dishes can be made from either exclusively from the flowers themselves or by incorporating them alongside other plant parts like stems and leaves. Some EFs with high RFC value, such as Musa acuminata and Bauhinia variegata var. candida, showed significant cultural meanings. These edible flowers occupy specific positions in local traditional culture.

CONCLUSION

Traditional knowledge regarding edible flowers holds substantial significance and serves as a representative element of the flower-eating culture in Xishuangbanna. Nevertheless, this knowledge and cultural practice are currently decreasing. Serving as a bridge between tradition and modernity, the flower-eating culture, which derives from local people's practical experience, shows the potential of EFs and can be applied to the conservation of biocultural diversity, healthy food systems, and sustainable development.

Nutraceutical potential, and antioxidant and antibacterial properties of Quararibea funebris flowers

The flowers of Quararibea funebris tree are an important component of tejate, a traditional Mexican beverage. The flowers exhibited a high concentration of total polyphenolic compounds, total carotenoids, and vitamin C. UPLC analysis revealed the presence of salicylic acid, kaemferol-3-O-glucoside, trans-cinnamic acid, rutin, scopoletin, l-phenylalanine, 4-coumaric acid and quercetin-3-glucoside, among others metabolites. The flowers exhibited volatile compounds as isolongifolene, α-cedrene, 2,5,5-trimethyl-2,3,4,5,6,7-hexahydro-1H-2,4a-ethanonaphthalene, while that linoleic acid, palmitic acid, and linolenic acid were the major fatty acids present in the oil extract. Magnesium, potassium, and calcium were the minerals most abundant in the flowers. In addition the methanolic extract of the flowers exhibited antimicrobial properties against the tested pathogenic microbial strains. In conclusion, these results showed that the Q. funebris flowers not only have an aromatic and flavoring power for the Tejate beverage, but also contains compounds with antioxidant, antimicrobial, and nutraceutical potential, which helps to explain its therapeutic uses.

Flowers and Inflorescences of Selected Medicinal Plants as a Source of Triterpenoids and Phytosterols

Steroids and triterpenoids are compounds valued for their various biological and pharmacological properties; however, their content in medicinal and edible plants is often understudied. Flowers have been consumed since the ancient times as a part of traditional cuisine and as alternative medicines. Currently, the interest in medicinal and edible flowers is growing since contemporary consumers are incessantly seeking innovative natural sources of bioactive compounds. The aim of this report was the GC-MS (gas-chromatography-mass spectrometry) analysis of steroid and triterpenoid content in flowers, inflorescences and leaves of several plants (Berberis vulgaris L., Crataegus laevigata (Poir.) DC., Pulsatilla vulgaris Mill., Rosa rugosa Thunb., Sambucus nigra L. and Vinca minor L.), applied in herbal medicine in various forms, including isolated flowers (Flos), inflorescences (Inflorescentia) or aerial parts (Herba, i.e., combined flowers, leaves and stems). The most abundant source of triterpenoids was V. minor flowers (6.3 mg/g d.w.), whereas the steroids were prevailing in P. vulgaris flowers (1.8 and 1.1 mg/g). The profiles of triterpenoid acids and neutral triterpenoids in C. laevigata and S. nigra inflorescences were particularly diverse, involving compounds belonging to lupane-, oleanane- and ursane-type skeletons. The obtained results revealed that some flowers can constitute an abundant source of phytosterols and bioactive triterpenoids, valuable for utilization in functional foods, dietary supplements and cosmetic products.

Effect of the Drying Method and Optimization of Extraction on Antioxidant Activity and Phenolic of Rose Petals

The effect of freeze and hot air drying methods on the retention of total phenolics, antioxidant activity (AA), and color of different cultivars of rose petals was analyzed. Both methods similarly preserved the phenolic content and AA, while freeze drying showed better red color retention. Furthermore, the conditions of total phenolics and AA extraction from two rose cultivars, Lovely Red and Malu, were optimized by response surface methodology through a Box–Behnken design. The solvent exhibited a major effect on the total phenolic content (TPC) and AA. The selected parameters were ethanol 38%, 75 °C, and 30 min. Under these conditions, the predicted values for Lovely Red were 189.3 mg GA/g dw (TPC) and 535.6 mg Trolox/g dw (AA), and those for Malu were 108.5 mg GA/g dw (TPC) and 320.7 mg Trolox/g dw (AA). The experimental values were close to the predicted values, demonstrating the suitability of the model. Ultrasound-assisted extraction increased the AA of the extracts but not the TPC. Fifteen compounds were identified in the Lovely Red cultivar, with no differences between the two drying methods. The results obtained suggest that the analyzed cultivars, particularly the red ones, can be considered a natural source of powerful antioxidant compounds.

Effect of Overfilled Solvent and Storage Time of Subcritical Extraction of Jasminum sambac on Yield, Antioxidant Activity, Antimicrobial Activity and Tentative Volatile Compounds

Essential oil from Jasminum sambac flowers has demonstrated the potential of antioxidant and antimicrobial properties. However, jasmine flowers contain only a small amount of essential oil; therefore, subcritical fluid extraction (SFE) with HFC-134a, one of the effective extraction methods for flower extraction, was performed in this study. The percentage of overfilled solvent and storage time of the flowers were varied during the extraction. Antioxidant potential, antimicrobial potential and tentative volatile compounds were investigated in this study to observe the quality of the essential oil. It was discovered that a greater amount of overfilled solvent resulted in thicker essential oil and a longer storage time resulted in a lower amount of total oil yield. It could be seen that almost all extraction conditions did not have any significant difference in antioxidant and antimicrobial potential. The essential oil contained primary compounds such as indole, 9-tricosene, α-farnesene, muurolene, and benzyl alcohol. This study led to the conclusion that the amount of overfilled solvent from SFE affected the thickness of jasmine essential oil and its tentative volatile compounds. The longer storage time caused the significantly lower essential oil yield, but changing the extraction conditions had no significant effect on antioxidant or antimicrobial potential.

Ultrasonic Enhancement of Aqueous Two-Phase Extraction and Acid Hydrolysis of Flavonoids from Malvaviscus arboreus Cav. Flower for Evaluation of Antioxidant Activity

The ultrasonic-assisted aqueous two-phase extraction (UAATPE) of flavonoid glycosides from Malvaviscus arboreous Cav. flower (MACF) was developed using ethanol/ammonia sulfate systems, followed by the ultrasonic-assisted acid hydrolysis (UAAH) of the top extract with HCl solution. The optimization of UAATPE and UAAH processes was accomplished by single-factor experiments and response surface methodology. As a result, the flavonoid glycosides enriched in the top phase could achieve a maximum yield of 35.9 ± 1.1 mg/g by UAATPE and were completely hydrolyzed by UAAH deglycosylation. The flavonoid glycosides and their hydrolyzates were separated and characterized by high-performance liquid chromatography and ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. Ultrasonic enhancement of the extraction and hydrolysis was explored by comparative study. Furthermore, the in vitro activity of the flavonoid glycosides and the aglycones were comprehensively evaluated by antioxidant activity assays, including ferric-reducing antioxidant power and scavenging DPPH, hydroxyl, and superoxide radicals. All of the IC₅₀ values suggest that the antioxidant activity of flavonoid aglycones was stronger than that of their glucosides and even vitamin C, revealing that the deglycosylated flavonoids from MACF were the more powerful antioxidants. This study provided an effective and eco-friendly strategy for the extraction, separation, and purification of flavonoids from MACF, as well as for the development of the potential flavonoid antioxidants.

Nature's palette: An emerging frontier for coloring dairy products

Consumers all across the world are looking for the most delectable and appealing foods, while also demanding products that are safer, more nutritious, and healthier. Substitution of synthetic colorants with natural colorants has piqued consumer and market interest in recent years. Due to increasing demand, extensive research has been conducted to find natural and safe food additives, such as natural pigments, that may have health benefits. Natural colorants are made up of a variety of pigments, many of which have significant biological potential. Because of the promising health advantages, natural colorants are gaining immense interest in the dairy industry. This review goes over the use of various natural colorants in dairy products which can provide desirable color as well as positive health impacts. The purpose of this review is to provide an in-depth look into the field of food (natural or synthetic) colorants applied in dairy products as well as their potential health benefits, safety, general trends, and future prospects  in food science and technology. In this paper, we listed a plethora of applications of natural colorants in various milk-based products.

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.

High throughput analytical approach based on μQuEChERS combined with UHPLC-PDA for analysis of bioactive secondary metabolites in edible flowers

Mallow blue (Malva sylvestris L.), hibiscus (Hibiscus rosa-sinensis L.) and nasturtium (Tropaeolum majus L.), are common edible flowers rich in bioactive secondary metabolites (BASMs) whose use in sophisticated gastronomy present currently as increasing trend. In this study the BASMs profile of these edible flowers was established using an emerging green extraction technique, μQuEChERS followed by ultra-high performance liquid chromatography coupled to a photodiode array detection system (UHPLC-PDA). After validation the μQuEChERS/UHPLC-PDA methodology allow to identify that apigenin and epigallocatechin gallate are the most abundant BASMs in mallow blue flowers, while catechin and dicaffeoylquinic acid are predominant in hibiscus flowers, and myricitrin and dicaffeoylquinic acid in nasturtium flowers. Total polyphenol content is the highest in the extract of hibiscus. Nasturtium shows the greatest radical scavenging activity. The results revealed that these flowers constitute a potential source of BASMs with different bioactive properties suggesting its use in design of new functional foods.

Potential of Probiotics as an Adjunct for Patients with Major Depressive Disorder

Major depressive disorder (MDD) is an enfeebling disease with a lifetime incidence of 20%. While accumulating studies implicate a correlation between the disease and gut microbiota, data show that not every patient responded to probiotic treatments. To comprehensively assess the potential role of probiotics in MDD, this study first summarizes the current pathological hypothesis of the disease from a life-stage perspective, focuses on the potential role of "depression gut microbiota." Currently available managements are then briefly summarized and novel bio-materials having potential therapeutic effects on MDD are also evaluated. To harness the positive effect of probiotics, prebiotics, and postbiotics, clinical evidence and their applications on MDD patients are listed. Factors that may counteract the pre/probiotic applications, such as diet, physiology, gender difference, and use of antibiotics and antidepressants are also discussed. The endocannabinoid (eCBs) system may be promising targets for probiotic therapy. More evidence is needed to demonstrate the hierarchical factors in the complex network driving the disease, and probiotic can be one promising adjunct for patients with MDD.

Phenolic profile and antioxidant activity of the selected edible flowers grown in Poland

The purpose of this study was to determine phenolic profile and antioxidant activity of the selected edible flowers grown in Poland. A significant variation was observed in the both antioxidant activity and total phenolic content. Marigold flowers were characterized by the highest total phenolic content (89.22 mg GEA/g dry weight). In turn, begonia flowers exhibited the highest total flavonoids and phenolic acids content (21.96 mg QE/g dry weight, and 8.60 mg CAE/g dry weight, respectively). Taking into account the type of flowers, begonia and marigold flowers were the richest in phenolic acids. Caffeic and p-coumaric acids were the most frequent ones in the edible flowers grown in Poland. While gallic and p-coumaric acids were the prevalent ones in terms of their content. The begonia and marigold flowers contained quercetin and kaempferol, while hesperetin and naringenin were present in the chives flowers. The marigold flowers were characterized by a particularly high content of quercetin, and also exhibited the highest total antioxidant activity. The methanolic extracts of marigold and begonia flowers were characterized by the highest antioxidant activity, reducing activity, as well as the highest ability to neutralize free radicals.

Antioxidant Potential of Flower Extracts from Centaurea spp. Depends on Their Content of Phenolics, Flavonoids and Free Amino Acids

Scientists intensely search for new sources of antioxidants, perceived as important health-promoting agents. Some species of the large genus Centaurea provide raw materials for the pharmaceutical and cosmetic industries, as well as produce edible flowers. This is the first study that determines the content of total polyphenols, flavonoids, reducing sugars, free amino acids and the antioxidant potential in the flower extracts of C. nigra L., C. orientalis L. and C. phrygia L. The total polyphenol and flavonoid content is the highest in the extract of C. orientalis, and the lowest in that of C. phrygia. Similarly, C. orientalis shows the greatest scavenging activity on DPPH (1,1-diphenyl-2-picryl-hydrazyl), ABTS [2,2′-azobis(3-ethylbenzothiazoline-6-sulfonate)] and Fe³⁺ reducing power assays, whereas the lowest activity is found for C. phrygia. The highest content of reducing sugars is found in C. nigra, while C. orientalis has the highest levels of free amino acids. We find a strong positive correlation between total phenolics and flavonoids and the antioxidant capacity of all three Centaurea species. Moreover, the content of free amino acids strongly and positively correlates with the levels of total phenolics and flavonoids, antioxidant activity assessed by DPPH and ABTS assays and Fe³⁺ reducing power. Summing up, C. orientalis exhibits the strongest antioxidant potential of the investigated Centaurea species. This species could potentially be a natural source of antioxidant substances for the pharmacy, cosmetics and food industries. The content of free amino acids may be used as a marker of the antioxidant status of Centaurea species.

Flower beverages of native medicinal plants from Argentina (Acacia caven, Geoffroea decorticans and Larrea divaricata) as antioxidant and anti-inflammatory

ETHNOPHARMACOLOGICAL RELEVANCE

Herbal beverages have been used as a natural part of the medicinal and food culture in northwestern Argentina. The flower beverages (infusion or decoction) of Acacia caven, Geoffroea decorticans and Larrea divaricata, three native species from arid and semiarid regions of Argentina are widely used as anti-inflammatory and anti-rheumatic by several local communities.

AIM OF THE STUDY

The aim of this study was to analyze the phytochemical composition of some Argentine flower beverage and to validate its traditional use as an antioxidant and anti-inflammatory agent.

MATERIALS AND METHODS

Phenolic profiles from all flower infusions and decoctions were analyzed by both spectrophotometric analysis and HPLC-DAD. ABTS^•+; the scavenging activity of both hydrogen peroxide and hydroxyl radical was determined and finally, their ability to inhibit pro-inflammatory enzymes, such as xanthine oxidase (XOD), and lipoxygenase (LOX) was also assessed.

RESULTS

The flower beverages of all assayed species showed a high level of phenolic compounds with similar chromatographic patterns in both infusions and decoctions of each plant species, the major components of which have been identified. The flower beverages, especially G. decorticans infusion and decoctions, displayed an important antioxidant activity (SC₅₀ values between 18.14 and 47 μg/mL) through different mechanisms; all of them were able to inhibit the XOD enzyme activity and, consequently, the formation of uric acid and reactive oxygen species, the primary cause of arthritis-related diseases. The most active beverages as XOD inhibitor were G. decorticans flower infusion and decoctions (IC₅₀ values of 20 and 35 μg/mL, respectively). Pro-inflammatory enzymes, such as LOX, were also inhibited by infusions and decoctions of G. decorticans, L. cuneifolia and A caven flowers, lessening inflammation mediators in all beverages.

CONCLUSIONS

The present work validates the traditional medicinal use of flower beverages from Argentina as an anti-rheumatic and anti-inflammatory agent as it has been used for hundreds of years in several pathologies associated with oxidative stress.

Phytochemical profiles of edible flowers of medicinal plants of Dendrobium officinale and Dendrobium devonianum

The discovery of new edible flowers that are nontoxic, innocuous flowers having human health benefits, surveys of their phytochemicals and utilization are of great scientific and commercial interest. Dendrobium officinale and Dendrobium devonianum are precious Traditional Chinese Medicine. During the massive commercial cultivation, a lot of flowers were produced and certified as edible flowers, and the phytochemical profiles and bioactivities warrant evaluate. The present study aimed to investigate the phytochemicals and antioxidative activities in flowers of D. officinale (DOF) and D. devonianum (DDF). In total, 474 metabolites were identified using a widely targeted metabonomics method, 16 amino acids and 6 flavonoids were measured using high-performance liquid chromatography (HPLC), and 8 fatty acids were detected using gas chromatography-mass spectrometry (GC-MS). Both flowers contained various amino acids, including 7 essential amino acids, diverse flavonoids, especially quercetin, kaempferol and their derivatives, and high levels of methyl linoleate and methyl linolenate. The relative levels of quercetin, kaempferol and their glycosides were higher in DDF than in DOF, whereas the relative levels of several flavonoids C-glycosides were high in DOF. Ethanol extracts of both DOF and DDF showed antioxidative capacities including the scavenging of 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals. Both edible flowers contained flavonoids, amino acids, and fatty acids and have antioxidative activities, which should be explored for use in functional foods and pharmaceuticals.

Nutritional Composition, In Vitro Antioxidant Activity and Phenolic Profile of Shortcrust Cookies Supplemented by Edible Flowers

In this study, the changes in nutritional composition, phenolic compounds and antioxidant activity in free and bound fractions of shortcrust cookies were investigated. By incorporating ingredients such as kamut, matcha tea, dried mango and jasmine flowers, the contents of crude and neutral-detergent fibre reached up to 2.0% and 5.0%, respectively. Similar increments were observed in phenolic compound contents and 2,2-diphenyl-1-picrylhydrazyl scavenging activity values. Concerning cookies supplemented with matcha tea, the total phenolic compound content raised from 1.0 to 4.8 mg gallic acid equivalent/g and the antioxidant activity value increased from 0.5 to 5.7 mg trolox equivalent/g on a dry weight basis. For determining the antioxidant activity values in water-soluble and insoluble phenolic fractions of the cookies, a photochemiluminiscence assay was separately applied, and they were found up to 0.8 mg ascorbic acid equivalent/g and 3.2 mg trolox equivalent/g, respectively. The main phenolic compounds in all supplemented cookies were neochlorogenic, gallic and vanillic acids.

Chemical Identification of Specialized Metabolites from Sulla (Hedysarum coronarium L.) Collected in Southern Italy

Sulla (Hedysarum coronarium L.) is a biennal forage legume originated from the Mediterranean basin and used for animal feeding due to its high forage quality and palatability. Several species of Hedysarum have been considered for their nutritional, pharmaceutical, and biological properties, and different applications have been reported, both for human consumption and animal nutrition. Although a systematic investigation of the chemical constituents of Hedysarum spp. has been performed in order to provide chemotaxonomic evidences for the genus and to support the pharmacological application of several species within the genus, few data are available on the chemical constituents of H. coronarium, and only the content of condensed tannins and flavonoids in leaves has been previously reported. In the present paper, results from a detailed chemical analysis of the extracts from the leaves and flowers of H. coronarium grown wild in southern Italy are presented. Identification of the main specialized metabolites within the chemical classes of flavonoids, proanthocyanidins and saponins, is described, including considerations on their content in the two plant organs. Information acquired from this study expands the knowledge on H. coronarium as a source of valuable phytochemicals for different applications in human and animal health and nutrition.

Antioxidant and anticancer potentials of edible flowers: where do we stand?

Edible flowers are attracting special therapeutic attention and their administration is on the rise. Edible flowers play pivotal modulatory roles on oxidative stress and related interconnected apoptotic/inflammatory pathways toward the treatment of cancer. In this review, we highlighted the phytochemical content and therapeutic applications of edible flowers, as well as their modulatory potential on the oxidative stress pathways and apoptotic/inflammatory mediators, resulting in anticancer effects. Edible flowers are promising sources of phytochemicals (e.g., phenolic compounds, carotenoids, terpenoids) with several therapeutic effects. They possess anti-inflammatory, anti-diabetic, anti-microbial, anti-depressant, anxiolytic, anti-obesity, cardioprotective, and neuroprotective effects. Edible flowers potentially modulate oxidative stress by targeting erythroid nuclear transcription factor-2/extracellular signal-regulated kinase/mitogen-activated protein kinase (Nrf2/ERK/MAPK), reactive oxygen species (ROS), nitric oxide (NO), malondialdehyde (MDA) and antioxidant response elements (AREs). As the interconnected pathways to oxidative stress, inflammatory mediators, including tumor necrosis factor (TNF)-α, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), interleukins (ILs) as well as apoptotic pathways such as Bcl-2-associated X protein (Bax), Bcl-2, caspase and cytochrome C are critical targets of edible flowers in combating cancer. In this regard, edible flowers could play promising anticancer effects by targeting oxidative stress and downstream dysregulated pathways.

The Effects of Post-Harvest Treatments on the Quality of Agastache aurantiaca Edible Flowers

Agastache spp. are used as ornamental plants for their pleasant aroma and the different colors of flowers. Nowadays, their edible flowers have become attractive for their nutraceutical properties. Post-harvest treatment appears as a crucial point to avoid impairment of the nutraceutical compounds and aroma, so different treatments were tested to analyze their effect on the bioactive metabolites and volatilome. Results indicated that freeze-drying was the best solution to prolong the shelf life of these flowers. The use of high temperatures (50, 60, 70 °C) led to altered the composition of antioxidant compounds (phenolic compounds, flavonoids, anthocyanins, carotenoids). Air-drying at 30 °C was a reasonable method, even though time consuming. Concerning the aroma profile, all samples were dominated by oxygenated monoterpene compounds. Pulegone was the main or one of the major constituents of all samples together with p-menthone. Gas Chromatography-Mass Spectrometry results showed a correlation between the temperature and the number of identified compounds. Both fresh and freeze-dried samples evidenced a lesser number (10 and 19, respectively); when the temperature raised, the number of identified constituents increased. Statistical analyses highlighted significant differences between almost all aromatic compounds, even if both Principal Component and Hierarchical Cluster analyses differed at 60 and 70 °C and from the other treatments.

Innovative Extraction Techniques Using Deep Eutectic Solvents and Analytical Methods for the Isolation and Characterization of Natural Bioactive Compounds from Plant Material

The growing interest of the food, pharmaceutical and cosmetics industries in naturally occurring bioactive compounds or secondary plant metabolites also leads to a growing demand for the development of new and more effective analysis and isolation techniques. The extraction of bioactive compounds from plant material has always been a challenge, accompanied by increasingly strict control requirements for the final products and a growing interest in environmental protection. However, great efforts have been made in this direction and today a considerable number of innovative extraction techniques have been developed using green, environmentally friendly solvents. These solvents include the deep eutectic solvents (DES) and their natural equivalents, the natural deep eutectic solvents (NADES). Due to their adjustable physical-chemical properties and their green character, it is expected that DES/NADES could be the most widely used solvents in the future, not only in extraction processes but also in other research areas such as catalysis, electrochemistry or organic synthesis. Consequently, this review provided an up-to-date systematic overview of the use of DES/NADES in combination with innovative extraction techniques for the isolation of bioactive compounds from various plant materials. The topicality of the field was confirmed by a detailed search on the platform WoS (Web of Science), which resulted in more than 100 original research papers on DES/NADES for bioactive compounds in the last three years. Besides the isolation of bioactive compounds from plants, different analytical methods are presented and discussed.