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A simple and rapid method is presented for the trace-level analysis of 10 polar pharmaceutical residues in various types of water samples from the aquatic environment. Using this method, the pharmaceuticals and several drug metabolites can be analyzed in drinking and surface waters and in wastewater (treated and untreated sewage) at concentrations down to 0.01 [micro]g/L. Samples are prepared by a simple in situ derivatization enabling the preconcentration of very polar metabolites by automated solid-phase extraction. The analytes were separated by liquid chromatography with tandem mass spectrometric detection and quantified by comparison with an internal standard. Limits of quantification were between 0.01 and 0.02 [micro]g/L for three phenazone-type pharmaceuticals, six of their metabolites, and the antiepileptic drug carbamazepine. Except for dimethylaminophenazone, recoveries for all analytes were between 87 and 117% for raw and purified sewage, groundwater, and surface and drinking water. Investigations of some environmental samples revealed that sewage and surface water treatment causes a slight reduction of the concentrations of some analytes whereas other compounds were persistent during water treatment. Thus, some compounds were detected at the low-microgram per liter level in sewage effluents of wastewater treatment plants in Berlin (Germany) and were also found at high-nanogram per liter concentrations in Berlin surface water samples.

Mycotoxin contamination of wheat kernels and diversity of fungal pathogens were monitored in a survey of 26 fields in Nakuru district, Kenya, in 2006. Sampling was performed twice; at mid-anthesis in July for leaves, stems and spikelets and at harvest in September for spikelets and kernels. Kernels were analysed for the occurrence of 32 mycotoxins using a high performance liquid chromatography – electrospray tandem mass spectrometry (LC-ESI-MS/MS) method. Fungi were isolated from surface-sterilized tissues and differentiated morphologically to the genus level. Fusarium isolates were identified based on the sequence of translation elongation factor 1-alpha gene. Eleven Fusarium-related mycotoxins were quantified with deoxynivalenol being detected at highest frequency (69%) and highest concentrations. Occurrence of enniatins in wheat (50%) is reported for the first time in Kenya. Non- Fusarium mycotoxins detected included aflatoxin G2, ochratoxin A, alternariol and alternariol monomethyl ether. Prevalence of Fusarium species on different wheat parts was 100% at both growth stages. Nineteen Fusarium species were identified with seven species – Fusarium chlamydosporum, Fusarium boothi, Fusarium poae, Fusarium scirpi, Fusarium arthrosporioides, Fusarium oxysporum and Fusarium graminearum– accounting for 80% of infections. At anthesis, spikelets and leaves were the most and least susceptible tissue, respectively. At harvest, infection of spikelets was 59% higher than that of kernels. [ABSTRACT FROM AUTHOR]

Biosynthesis of the hypericins that accumulate in the dark glands of some members of the genus Hypericum is poorly understood. The gene named hyp-1, isolated from Hypericum perforatum L. has been proposed as playing an important role in the final steps of hypericin biosynthesis. To study the role of this candidate gene in relation to the production of hypericins, the expression of this gene was studied in 15 Hypericum species with varying ability to synthesise hypericin. While the accumulation of hypericins and emodin, an intermediate in the respective pathway, was associated with the dark glands in the hypericin-producing species, the hyp-1 gene was expressed in all studied species regardless of whether hypericins and emodin were detected in the plants. The coding sequences of hyp-1 cDNA were isolated from all species and showed more than 86% similarity to each other. Although, in general, an increased level of the hyp-1 gene transcript was detected in hypericin-producing species, several of the hypericin-lacking species expressed comparable levels as well. Our results question the role of the hyp-1 gene product as a key enzyme responsible for biosynthesis of hypericins in the genus Hypericum. The function of the hyp-1 gene may not be restricted to hypericin biosynthesis only, or some additional factors are necessary for completion of hypericin biosynthesis.

A study has been carried out on the chemical composition and in vivo anti-oedematogenic activity of several extracts from Hypericum grandifolium Choisy (Hypericaceae) collected in Tenerife (Canary Islands). The HPLC-MS analysis (HPLC-ESI/MS and HPLC-FT/MS) revealed the presence of hyperforin, flavonoids and probably benzophenone derivatives, while naphthodianthrones were absent. Pharmacological results revealed that the methanol extracts and the aqueous, butanol and chloroform fractions obtained therefrom possess anti-oedematogenic activity against TPA-induced ear oedema and carrageenan-induced paw oedema, the chloroform fraction being the most active. Subfractions derived from the chloroform fraction also showed anti-oedematogenic activity. From these results, it can be suggested that different constituents, such as the flavonoids and the benzophenone derivatives, could be responsible, at least in part, for the anti-oedematogenic effects observed for this species.