The problem of misidentification between edible and poisonous wild plants: Reports from the Mediterranean area

Phytochemical and bioactive potentials of African Annonaceae species

This review aims to gather available information on the medicinal, nutritional, and bioactive profiles of Annonaceae species in the African continent, sponsoring their use worldwide and mainly in African communities, where access to food and medicines for basic health care is scarce. >60 medicinal taxa were compiled, belonging to 22 genera, namely Annickia, Annona, Anonidium, Artabotrys, Cleistochlamys, Cleistopholis, Dennettia, Duguetia, Greenwayodendron, Hexalobus, Isolona, Lettowianthus, Monanthotaxis, Monodora, Neostenanthera, Polyceratocarpus, Sphaerocoryne, Uvaria, Uvariastrum, Uvariodendron, Uvariopsis and Xylopia; the most diverse and economically important genera were the genera Annona, Uvaria and Xylopia with 7 species each. Annonaceae species hold a valuable nutritional profile, rich in proteins, fibers, and minerals, being also good sources of a wide range of bioactive compounds of high biological relevance. These compounds are especially important in developing countries, where most of these species are available for direct use as food and/or medicines by the most deprived populations.

Identification of toxic Gelsemium elegans in processed food and honey based on real-time PCR analysis

Gelsemium elegans (GE) is a widely distributed hypertoxic plant that has caused many food poisoning incidents. Its pollen can also be collected by bees to produce toxic honey, posing a great threat to the health and safety of consumers. However, for the complex matrices such as cooked food and honey, it is challenging to perform composition analysis. It is necessary to establish more effective strategies for investigating GE contamination. In this study, the real-time PCR (qPCR) analysis combined with DNA barcode matK was proposed for the identification and detection of GE. Fifteen honey samples along with twenty-eight individuals of GE and the common confusable objects Lonicera japonica, Ficus hirta, Stellera chamaejasme and Chelidonium majus were gathered. Additionally, the food mixtures treated with 20-min boiling and 30-min digestion were prepared. Specific primers were designed, and the detection capability and sensitivity of qPCR in honey and boiled and digested food matrices were tested. The results demonstrated that the matK sequence with sufficient mutation sites was an effective molecular marker for species differentiation. GE and the confusable species could be clearly classified by the fluorescence signal of qPCR assay with a high sensitivity of 0.001 ng/μl. In addition, this method was successfully employed for the detection of deeply processed food materials and honey containing GE plants which even accounted for only 0.1 %. The sequencing-free qPCR approach undoubtedly can serve as a robust support for the quality supervision of honey industry and the prevention and diagnosis of food poisoning.

Plant identification applications do not reliably identify toxic and edible plants in the American Midwest

INTRODUCTION

Exposure to potentially toxic plants is a global problem, resulting in thousands of calls to poison centers and emergency department visits annually and occasional deaths. Persons with limited botanical knowledge may be tempted to rely on smartphone applications to determine if plants are safe to forage. This study evaluated the reliability of several popular smartphone applications to identify foraged foods and distinguish them from potentially toxic plants in the Midwestern United States.

METHODS

Sixteen plant species were selected based on local availability, attractiveness as foraged food, and potential for misidentification. Of the 16 species, five are edible, three are potentially toxic if improperly harvested or prepared, and eight are considered to be toxic. Plant specimens were identified by graduate-level botanists and photographed during multiple stages of their growth cycles. LeafSnap, PictureThis, Pl@ntNet and PlantSnap were used to identify the plants.

RESULTS

Overall accuracy of the applications in identifying plant genus was 76% (95% confidence interval: 73-79, range 96% for PictureThis to 53% for PlantSnap). Accuracy for identification of plant species was 58% (95% confidence interval 55-62%, range 94% for PictureThis to 34% for PlantSnap). Five of eleven potentially toxic species were identified as an edible species by at least one application.

CONCLUSION

Accuracy of the smartphone applications varies, with PictureThis outperforming other apps. At this time, apps cannot be used to safely identify edible plants. Foragers must have adequate botanical knowledge to ensure safe harvesting of wild plants.

Risk of Poisoning from Garden Plants: Misidentification between Laurel and Cherry Laurel

The misidentification between edible and poisonous plants is an increasing problem because of the new trend to collect wild plants, especially by amateur collectors who do not have the botanical skills to distinguish between edible and toxic species. Moreover, morphologically similar species are sometimes responsible for accidental contamination or used in the intentional adulteration of products for human and animal consumption. Laurus nobilis L. (laurel) and Prunus laurocerasus L. (cherry laurel) are typical ornamental shrubs of the Mediterranean region. Laurel is considered a non-toxic plant, widely used as flavorings. Conversely, cherry laurel leaves, morphologically similar to those of laurel, contain toxic cyanogenic glycosides. Considering this, the aim of this study was to carry out an in-depth evaluation of laurel and cherry laurel leaves by using light and scanning electron microscopy coupled with three step phytochemical analyses (qualitative and quantitative colorimetric assays and liquid chromatography). This allowed to highlight the distinguishing features of plant species investigated features such as the venation pattern, presence/absence of nectaries, calcium oxalate crystals, secretory idioblasts, and cyanogenic glycosides. Concluding, this multidisciplinary approach can be useful for the identification of plants but also fragments or pruning residues containing cyanogenic glycosides, in quality control tests, intoxications, and criminal cases.

Plant Poisons in the Garden: A Human Risk Assessment

A study of the plants, and their associated poisons, in the Poison Garden at The Alnwick Garden was undertaken across a calendar year. By selecting 25 plants in the Poison Garden, we have been able to develop a single chromatographic method for the determination and quantification of 15 plant toxins by liquid chromatography mass spectrometry (LC-MS). Chromatographic separation was achieved on a C18 column (3.5 µm, 100 × 4.6 mm) with a gradient method using water +0.1% formic acid and methanol +0.1% formic acid. The developed method was validated for precision, linearity, limits of detection and quantification and extraction recoveries. The method showed good linearity with a R2 value of >0.995 for all 15 compounds with good precision of 10.7%, 6.7% and 0.3% for the low, medium and high calibration points, respectively. The LC-MS method was used to analyse 25 plant species, as well as their respective parts (i.e., bulb, flower, fruit, leaf, pollen, seed, stem and root), to assess the human risk assessment to children (aged 1 to <2 years) in relation to the plant toxin and its respective LD50. The analysis found that the greatest potential health risks were due to the ingestion of Colchicum autumnale and Atropa belladonna. As a caution, all identified plants should be handled with care with additional precautionary steps to ensure nil contact by children because of the potential likelihood of hand-to-mouth ingestion.

Barcoding High Resolution Melting (Bar-HRM) enables the discrimination between toxic plants and edible vegetables prior to consumption and after digestion

The consumption of poisonous plants can lead to serious health problems or even casualties due to various factors, including easy access to poisonous plants due to their common distribution, co-occurrence and resemblance with edible plants, and the lack of regulation in the food product supply chain. Clinical diagnosis of intoxications usually relies on the availability of the plant consumed by the patient and on the morphology of the plant parts found in the patient's stomach. Therefore, given the fragmented nature of ingested plant material, species identification may face serious difficulties, can be inaccurate, and time-consuming. This highlights the need for rapid and reliable tools to identify toxic species. In the present study, we developed an ITS2-high-resolution melting (HRM) assay for: (1) the discrimination of common toxic plants and their edible lookalikes, and (2) the detection of toxic plants in digested samples. More specifically, we designed species-specific ITS2 primers for the authentication of poisonous species in simulated mixtures and verified them with Bar-HRM. Moreover, the developed HRM-based molecular tool was capable of quantifying the toxic species Datura stramonium in simulated mixtures with the edible Amaranthus retroflexus down to at least 0.5% v/v. This study shows that species-specific ITS2 primers can amplify the DNA from fragmented and/or artificially digested samples and that Bar-HRM is capable of detecting poisonous plant species in digested samples even after 4 h. The developed Bar-HRM protocol has important implications for application in medicine, forensics, and the agricultural industry, either to accurately detect the cause of plant intoxications or as a tool for quality control in the supply chain. PRACTICAL APPLICATION: In this work, we established a high-resolution melting DNA-based protocol capable of discriminating between phenotypically similar common toxic and edible plant species in mixtures, even at very low quantities. This technology also proved efficient in detecting the toxic species in mixtures digested in artificial gastric acid, as it would be the case after accidental ingestion. This work is expected to have important implications for application in medicine, forensics, and the agricultural industry, either for identifying the cause of plant intoxications or as a tool for quality control in different steps of the supply chain.

Characterization of Ingredients Incorporated in the Traditional Mixed-Salad of the Capuchin Monks

Recipes on the composition of the “salad of the monks” (Capuchin monks) have been reported in Italy since the 17th century. Different wild edible plants were highly regarded as an important ingredient of this mixed salad. Among these, some species played a key role for both their taste and nutritional properties: Plantago coronopus L. (PC), Rumex acetosa L., Cichorium intybus L., and Artemisia dracunculus L. In the present study, the micromorphological and phytochemical features as well as the antioxidant and anti-inflammatory properties of extracts of these fresh and blanched leaves, were investigated. The extracts obtained by blanched leaves, according to the traditionally used cooking method, showed the highest content of bioactive compounds (total phenols 1202.31–10,751.88 mg GAE/100 g DW; flavonoids 2921.38–61,141.83 mg QE/100 g DW; flavanols 17.47–685.52 mg CE/100 g DW; proanthocyanidins 2.83–16.33 mg CyE/100 g DW; total chlorophyll 0.84–1.09 mg/g FW; carbohydrates 0.14–1.92 g/100 g FW) and possess the most marked antioxidant (IC₅₀ 0.30–425.20 µg/mL) and anti-inflammatory activity (IC₅₀ 240.20–970.02 µg/mL). Considering this, our results indicate that increased consumption of the investigated plants, in particular of PC, raw or cooked briefly, could provide a healthy food source in the modern diet by the recovery and enhancement of ancient ingredients.

DNA-Based Herbal Teas' Authentication: An ITS2 and psbA-trnH Multi-Marker DNA Metabarcoding Approach

Medicinal plants have been widely used in traditional medicine due to their therapeutic properties. Although they are mostly used as herbal infusion and tincture, employment as ingredients of food supplements is increasing. However, fraud and adulteration are widespread issues. In our study, we aimed at evaluating DNA metabarcoding as a tool to identify product composition. In order to accomplish this, we analyzed fifteen commercial products with DNA metabarcoding, using two barcode regions: psbA-trnH and ITS2. Results showed that on average, 70% (44-100) of the declared ingredients have been identified. The ITS2 marker appears to identify more species (n = 60) than psbA-trnH (n = 35), with an ingredients' identification rate of 52% versus 45%, respectively. Some species are identified only by one marker rather than the other. Additionally, in order to evaluate the quantitative ability of high-throughput sequencing (HTS) to compare the plant component to the corresponding assigned sequences, in the laboratory, we created six mock mixtures of plants starting both from biomass and gDNA. Our analysis also supports the application of DNA metabarcoding for a relative quantitative analysis. These results move towards the application of HTS analysis for studying the composition of herbal teas for medicinal plants' traceability and quality control.

Ethnobotany of the Aegadian Islands: safeguarding biocultural refugia in the Mediterranean

BACKGROUND

The Aegadian Islands are located west of Trapani, Sicily. Once the site of bountiful tuna fisheries and fruit orchards (plums, peaches, apricots), grapevines, prickly pears, and grains, the local economy is now based on tourism, and many traditional agricultural and maritime practices have been abandoned. In this study, we aimed to evaluate the state of traditional ecological knowledge (TEK) concerning the use of wild and cultivated plants and fungi for human health, food, maritime, and agricultural purposes on the islands of Levanzo, Favignana, and Marettimo and compare present-day practices with those documented in the past.

METHODS

In-depth semi-structured interviews were conducted in Italian with 48 participants with prior informed consent from May 2016 to July 2017 and October 2018. Herbarium voucher specimens of wild species were collected for herbarium deposit. A rigorous literature review of scientific and other local reports on TEK of wild flora and their application in food, health, and household applications was undertaken for the purpose of comparing findings from this field study with prior reports.

RESULTS

A total of 122 plant and five fungal taxa representing 54 families were cited for 355 uses. Among the most pervasive species in the landscape, Agave americana and A. sisalana had diverse applications in the past, which ranged from cordage for agricultural and maritime applications to tools for sewing, eating land snails, and constructing furniture. Fields of Ferula communis also dominate the landscape, and the dry stems were used extensively in furniture making; this species also serves as an environmental indicator for the location of the most preferred edible mushrooms, Pleurotus eryngii var. ferulae. Other important flora included topical medicinal applications of Glaucium flavum for hematomas and Artemisia arborescens for ritual bathing of newborns.

CONCLUSION

While many plant-based traditions have disappeared from daily practice, especially those related to traditional fishing and health practices, they remain in the memories of the eldest subset of the population. Documenting this knowledge before it disappears from oral history is a key factor in reducing loss of TEK and biocultural diversity, safeguarding the role of the Aegadian Islands as biocultural refugia.

Culinary and nutritional value of edible wild plants from northern Spain rich in phenolic compounds with potential health benefits

Wild edible plants (WEPs) have been consumed since ancient times. They are considered as non-domesticated plants that grow spontaneously in nature, particularly in forests and bushlands, where they can be found and collected to be incorporated into human nutrition. Increasingly, WEPs are gaining importance as they are potential sources of food due to their nutritional value, besides showing positive health effects and offer innovative applications in haute cuisine. As these autochthonous plants grow naturally in the environment, they are more suitable to adapt to different climatic conditions as well as biotic and abiotic factors. Therefore, a door has been opened for their possible cultivation as they seem to require fewer expenses than other commercially cultivated plants. Moreover, the consumers demand for new products of natural origin that are sustainable and ecologically labeled have also boosted WEPs' recovery and incorporation into the market. In addition, they are considered as promising sources of essential compounds needed not only in human diet including carbohydrates, proteins, and lipids but also of other minor compounds as phenols, vitamins, or carotenoids that have shown numerous beneficial bioactivities such as antioxidants, anti-inflammatory, or anti-tumor activity. The use of these plants rich in bioactive molecules could be beneficial from the health point of view as the human body is not always capable of producing enough defenses, for instance, preventing oxidative damage. In particular, the presence of phenolic compounds in these vegetal matrices is supposed to provide a prophylactic effect against further pathogenesis and disorders related to aging or oxidative stresses. Regarding all this information based on traditional knowledge and ethnobotanical data, different WEPs found in the Northwestern region of Spain were selected, namely, Mentha suaveolens, Glechoma hederacea, Prunus spinosa, Apium nodiflorum, Artemisia absinthium, Silybum marianum, Picris hieracioides, Portulaca oleracea, Crithmum maritimum, and the genus Amaranthus. However, even though tradition and popular knowledge are excellent tools for the exploitation of these plants, it is necessary to develop regulations in this aspect to assure safety and veracity of food products. This article aims to review the main aspects of their bioactive properties, their traditional use, and the possibility of their incorporation into the market as new functional foods, looking at innovative and healthy gastronomic applications.

The Seeds of Doubt: Finding Seeds in Intriguing Places

Introduction: Seeds may be found in gastrointestinal tissue samples, and their multifaceted appearance may be challenging. The aim is to report a rough incidence of pathology samples which show seeds, specify the most frequent sample types and show an iconography of the most commonly identified seeds. Materials and Methods: Between 2017 and 2020, all gastrointestinal pathology cases in which seeds/seed parts were found, were collected and seed type described by referencing a seed image library. Results: Fifty cases with complete seeds/seed parts were collected: 16 colonic resections for colorectal cancer and diverticulosis, 13 appendiceal resections for appendicitis, 1 gastric resection. Fifteen cases were found in polypectomy specimens and 5 cases in colorectal endoscopic biopsies. Most frequent seed types were tomato, kiwi, blueberry, and blackberry seeds. Conclusion: Seeds may be found in up to 4% of specimens; their recognition may be useful to exclude parasitic infections as well as in forensic sciences.

Determination of atropine and scopolamine in spinach-based products contaminated with genus Datura by UHPLC-MS/MS

Datura species are well known because of their high concentration of tropane alkaloids, which has led to poisoning episodes when Datura is accidentally mixed with edible crops. Therefore, the European Union has set a maximum level in cereal-based infant food products of 1 µg kg^-1 for atropine and scopolamine. However, the occurrence of these compounds in other commodities has become a global concern. Spinach and derived products can be contaminated with Datura innoxia leaves. In this study, we tested frozen spinachs and spinach-based infant food products. The determination was carried out by UHPLC-MS/MS after applying the QuEChERS method as sample treatment. The LOQs were below 0.016 µg kg^-1, achieving satisfactory results in terms of precision, accuracy, and matrix effects. The obtained results (ranging between 0.02 and 8.19 µg kg^-1) were close to the maximum level set by the European Union for 24% of the samples tested.

Investigations of Phytoconstituents, Antioxidant and Anti-Liver Cancer Activities of Saueda monoica Forssk Extracted by Microwave-Assisted Extraction

Background:

Wild edible plants are good sources for bioactive compounds, vitamins, and minerals with various applications. They can play a role in supporting the immune system and are highly beneficial as resources. Suaeda monoica Forssk is a wild edible plant that grows in Iraq and it’s biological activities have not yet reported.

Methods:

Saueda monoica Forssk bioactive compounds were extracted by a microwave-assisted extraction method using ethanol as a solvent, and its chemical composition was analyzed by GC-MS. The biological activities were evaluated via antioxidant, anti-liver-cancer, antibacterial, and toxicity tests in vitro.

Results:

The results of GC-MS analysis showed that there were about 20 bioactive compounds. The most abundant compound was N,N-Dimethylglycine methyl ester, followed by 9,12,15-Octadecatrienoic acid, n-Hexadecanoic acid, and N,N-Dimethylglycine. The antioxidant activity of the ethanol extract of the plant showed a significant IC₅₀. The extract of S. monoica against liver cancer cells (HCAM) showed significant toxicity. Flow cytometric analysis showed a significant induced apoptosis and cell cycle arrested at G1 phase.

Conclusions:

The results indicated the significance of the components of Iraqi S. monoica Forssk by MAE method as a potential food supplement in nutrition systems to prevent liver cancer and enhance the liver’s defense against diseases.