Botanical Briefs: Phytophotodermatitis Caused by Giant Hogweed (Heracleum mantegazzianum).

Giant hogweed (Heracleum mantegazzianum) is an invasive flowering weed that can reach a height of 13 feet. Although it is the appearance of the plant that can draw attention, contact with the sap in combination with exposure to the sun can result in severe phytophotodermatitis. Due to the growing prevalence of giant hogweed, the number of cases of H mantegazzianum-associated phytophotodermatitis in the United States is increasing. We report the case of a 27-year-old man who presented with a blistering rash on the neck and arms that developed 18 to 24 hours after trimming giant hogweed plants without photoprotection. A diagnosis of giant hogweed phytophotodermatitis should be considered for patients presenting with acute erythema and bullae in sun-exposed areas after exposure to the plant. Additionally, the public would benefit from education, especially during summer months, on identifying the plant and reducing phototoxin exposure to reduce the risk for phytophotodermatitis.

Keeping pace with the media; Giant Hogweed burns - A case series and comprehensive review.

Phytophotodermatitis is almost exclusively reported in the dermatological literature, but may progress to a chemical burn. There has been widespread media reporting during the summer of 2015 of burns caused by giant hogweed. However, there is a lack of awareness of this mechanism of injury amongst the burn multidisciplinary team, and there have been no published articles in the surgical literature regarding plant burns, other than sporadic case reports, for 20 years. We present a comprehensive review of plant burns and three cases from our adult and paediatric Burn Centres of burns caused by giant hogweed. Accurate diagnosis is straightforward with a detailed history and is important to prompt appropriate treatment, and prevent a misdiagnosis of non-accidental injury. This review and case series are timely to raise awareness of phytophotodermatitis and burns caused by plants to burns multidisciplinary teams. Prospective studies are warranted to assess the efficacy of topical treatments and surgical management.

Chemical compositions and antioxidant activity of Heracleum persicum essential oil

ABSTRACT In this study essential oil of the aerial parts of Heracleum persicum a spice widely used in Iran was isolated by conventional hydrodistillation (HD) and microwave-assisted hydrodistillation (MAHD) techniques. The extraction yield was determined and the chemical compositions of essential oils were identified by the application of gas chromatography/mass spectrometry (GC/MS). The antioxidant activity was determined by two different methods: 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and oven test methods. Although the main compounds of essential oils by the both extraction methods were similar, the essential oil extracted by HD with lower extraction efficiency showed more diverse compounds. The evaluation of antioxidant activity of the essential oil measured by delay in sunflower oil oxidation indicated that the antioxidant activity was dependent on the concentration which increased when higher concentrations of the essential oils were applied. The results of DPPH radical assay also indicated that the percentage of inhibition increased with increasing of essential oil concentration and IC50 value for essential oil extracted by MAHD method was obtained 1.25 mg/mL. Therefore the Heracleum persicum essential oil might be recommended for use as a flavoring agent and a source of natural antioxidants in functional foods, formulation of the supplements and in medicinal due to numerous pharmacological activities.

Photoallergic contact dermatitis to Heracleum giganteum.

Heracleum plants occur in numerous species worldwide and may cause phototoxic reactions due to its content of various furocoumarins. In this case report, a widespread photoallergic contact dermatitis after exposure to Heracleum giganteum (giant bear claw) is described. A photopatch test with extracts from the stem, leaves and seeds of the giant bear claw revealed a positive papulovesicular reaction that already appeared at 24 h and peaked at 72 h after irradiation with 5 J/cm(2) UVA. The unirradiated controls remained negative. We conclude that in rare cases Heracleum plants may cause severe photoallergic reactions that can be verified by photopatch testing.

Heracleum mantegazzianum and Toxicodendron succedaneum: plants of human health significance in New Zealand and the National Pest Plant Accord.

New Zealand's National Pest Plant Accord (NPPA) is a voluntary and cooperative agreement between industry, regional councils, and central government departments with biosecurity responsibilities (primarily the Ministry of Agriculture and Forestry and the Department of Conservation). Plant species included in the NPPA are declared unwanted organisms under the Biosecurity Act 1993, which prevents their sale, propagation, or distribution across the country. Although MAF Biosecurity New Zealand (the lead agency in New Zealand's biosecurity system) has evaluated the potential human health impacts of 202 species considered for inclusion in the NPPA, two species were examined primarily due to their significance to human health: Heracleum mantegazzianum (giant hogweed, cow parsnip, wild parsnip) and Toxicodendron succedaneum (rhus tree, wax tree, Japanese wax tree). As a result of this process, H. mantegazzianum has been listed in the NPPA. In contrast, T. succedaneum was not included in the NPPA, as the latter was deemed to be an inappropriate mechanism for its control. In this article the NPPA process is outlined, and the adverse impacts on human health of these two species are discussed--including symptoms, treatment, and possible management measures.