Invasive alien species are one of the major agents of human-accelerated global change: they threaten biodiversity, alter ecosystem structure, functions and services, inflict large economic costs and cause serious problems to human health. The effects on human health are indeed a major problem and also cause substantial costs but, surprisingly, very few studies have analyzed this topic. The paper describes and analyses the hazards to human health associated with species introductions, and discusses major correlates and possible responses. Four categories were identified: invasive species (1) causing diseases or infections; (2) exposing humans to wounds from bites/stings, biotoxins, allergens or toxicants; (3) faciliting diseases, injuries or death; and (4) inflicting other negative effects on human livelihood. Invasive species affect human health via several ways, i.e. as alien pathogens and invaders that bring/facilitate parasites or produce toxins. Others cause denutrition/malnutrition or exert displaced or deferred impacts. Their negative impacts are expected to intensify in the near future due to the increased opportunities of invasions associated with climate change, the augmented pathways of introductions and the synergic effects of climate change. It is imperative to improve our understanding of the pathways of arrival of invasive species affecting human health, their biological patterns and the mechanisms of impact, because all this information is essential to develop more effective and stringent policies for preventing and mitigating the negative effects that these species cause.

Sumac is the common name for a genus (Rhus) that contains over 250 individual species of flowering plants in the family Anacardiaceae. These plants are found in temperate and tropical regions worldwide, often grow in areas of marginal agricultural capacity, and have a long history of use by indigenous people for medicinal and other uses. The research efforts on sumac extracts to date indicate a promising potential for this plant family to provide renewable bioproducts with the following reported desirable bioactivities: antifibrogenic, antifungal, antiinflammatory, antimalarial, antimicrobial, antimutagenic, antioxidant, antithrombin, antitumorigenic, antiviral, cytotoxic, hypoglycaemic, and leukopenic. As well, the bioactive components can be extracted from the plant material using environmentally benign solvents that allow for both food and industrial end-uses. The favorable worldwide distribution of sumac also suggests that desirable bioproducts may be obtained at the source, with minimal transportation requirements from the source through processing to the end consumer. However, previous work has focussed in just a few members of this large plant family. In addition, not all of the species studied to date have been fully characterized for potential bioactive components and bioactivities. Thus, there remains a significant research gap spanning the range from lead chemical discovery through process development and optimization in order to better understand the full potential of the Rhus genus as part of global green technology based on bioproducts and bioprocesses research programs.

In the present study we investigated the metabolic conversion of cyanidin glycosides in human subjects using solid-phase extraction, HPLC–diode array detector, MS, GC, and enzymic techniques. Volunteers consumed approximately 20 g chokeberry extract containing 1·3 g cyanidin 3-glycosides (899 mg cyanidin 3-galactoside, 321 mg cyanidin 3-arabinoside, 51 mg cyanidin 3-xyloside and 50 mg cyanidin 3-glucoside). Blood samples were drawn at 0, 0·5, 1, and 2 h post-consumption of the extract. Urine samples were also collected at 0, 4–5, and 22–24 h. We have confirmed that human subjects have the capacity to metabolise cyanidin 3-glycosides, as we observed at least ten individual anthocyanin metabolites in the urine and serum. Average concentrations of anthocyanins and anthocyanin metabolites in the urine reached levels of 17·9 (range 14·9–20·9) μmol/l within 5 h post-consumption and persisted in 24 h urine samples at levels of 12·1 (range 11·1–13·0) nmol/l. In addition, average total levels of anthocyanins and anthocyanin metabolites detected in the serum were observed at 591·7 (range 197·3–986·1) nmol/l within 2 h post-consumption. Cyanidin 3-galactoside accounted for 55·4 % (9·9 (range 7·2–12·6) μmol/l) and 66·0 % (390·6 (range 119·4–661·9) nmol/l) of the detected anthocyanins in the urine and serum samples, respectively. The metabolites were identified as glucuronide conjugates, as well as methylated and oxidised derivatives of cyanidin 3-galactoside and cyanidin glucuronide. Conjugation probably affects the biological activity of anthocyanins and these metabolic products are likely in part responsible for the reported health benefits associated with the consumption of anthocyanins.

Anthocyanins are the largest group of water-soluble pigments in the plant kingdom. They are responsible for most of the red, blue, and purple colors of fruits, vegetables, flowers, and other plant tissues or products. The analysis of anthocyanins is complex as a result of their ability to undergo structural transformations and complexation reactions. In addition, they are difficult to measure independently of other flavonoids, as they have similar structural and reactivity characteristics. Anthocyanins are generally extracted with weakly acidified alcohol-based solvents, followed by concentration (under vacuum), and purification of the pigments. Paper and/or thin-layer chromatography and UV-Vis spectroscopy have traditionally been used for the identification of anthocyanins. Capillary zone electrophoresis, a hybrid of chromatography and electrophoresis, is gaining popularity for the analysis of anthocyanins; however, liquid chromatography (LC) has become the standard method for identification and separation in most laboratories and may be used for both preparative and quantitative analysis. LC with mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy are possibly the most powerful methods for the structural elucidation of anthocyanins available, to date. At present, the most satisfactory method for mixture analysis is the multistep method of separation, isolation, and quantification by LC with peak identification by MS and high-field NMR.