Sphingolipidoses in Morocco: Chemical profiling for an affordable and rapid diagnosis strategy

Sphingolipidoses are a group of metabolic diseases in which lysosomal hydrolases dysfunction disrupt normal sphingolipids' metabolism, leading to excess accumulation in cellular compartments and excretion in urine. These pathologies represent a significant burden among Moroccan population, for which an easy access to enzymatic assays and genetic tests is not guaranteed. Parallel analytical methods thus have to be developed for preliminary screening. In this study, 107 patients were addressed to the metabolic platform of the Marrakesh Faculty of Medicine for diagnosis confirmation. Thin-Layer Chromatography was used as a first step to perform chemical profiling of the patients' urinary lipids, allowing 36% of the patients to be efficiently oriented towards the adequate enzymatic assay. UPLC-MS/MS analyses of urinary sulfatides excreted in urines patient had been used to control the reliability of TLC analysis and to obtain more accurate information related to the sulfatides isoforms. This analytical process combining TLC with UPLC-MS/MS has enabled rapid and appropriate patient management in a reduced time and with reduced resources.

Efficient degradation of the organic UV filter benzophenone-3 by Sphingomonas wittichii strain BP14P isolated from WWTP sludge

Benzophenone-3 (BP3) is a widely used organic UV filter present in many environmental compartments. One way BP3 is released into the environment is through effluents from wastewater treatment plants (WWTPs). These plants are possible sources for degradation activity and WWTP sludge may potentially degrade BP3. Our goal was to identify any BP3 degrading microorganism(s) in WWTP sludge and to investigate whether the degradation was co-metabolic. Initial WWTP sludge microcosms spiked with BP3 showed 100% degradation after 20 days. Multiple transfers of these microcosms, while maintaining a strong selective pressure for BP3 degradation capabilities, resulted in the dominance of one bacterial strain. This strain was identified as Sphingomonas wittichii BP14P and was subsequently isolated. It was shown to degrade BP3 in a growth dependent manner. Strain BP14P utilized BP3 as the sole energy and carbon source and completely degraded BP3 after 7 days in minimal media. We tested the capability of BP14P to degrade nine other UV filters, but the degradation ability seemed to be restricted to BP3. However, whether this specificity is due to the lack of degradation genes, cellular transport or low bioavailability of the other UV filters remained unclear. The efficient degradation of BP3 by a group of bacteria well known for their potential for xenobiotic degradation is an important step forward for a complete risk assessment of the long-term environmental impact of BP3.

In vitro antidermatophytic activity of Otacanthus azureus (Linden) Ronse essential oil alone and in combination with azoles

AIMS

We determined the chemical composition and investigated the antifungal activity of Otacanthus azureus (Linden) Ronse essential oil (EO) against a range of dermatophytes alone or in combination with azole antifungals.

METHODS AND RESULTS

Aerial parts of the plant were steam-distilled and the obtained oil was analysed by gas chromatography/mass spectrometry and (1) H-NMR. It was shown to be largely composed of sesquiterpenes, with the main component being β-copaen-4-α-ol. Using broth microdilution techniques, this oil was found to have remarkable in vitro antifungal activities. Minimum inhibitory concentrations as low as 4 μg ml(-1) were recorded. The analysis of the combined effect of the O. azureus EO with azoles using chequerboard assays revealed a synergism between the EO and ketoconazole, fluconazole or itraconazole against Trichophyton mentagrophytes. Notably, the O. azureus essential oil showed low cytotoxicity to VERO cells.

CONCLUSIONS

The O. azureus essential oil alone or in combination with azoles is a promising antifungal agent in the treatment for human dermatomycoses caused by filamentous fungi.

SIGNIFICANCE AND IMPACT OF THE STUDY

There is much interest in the study of essential oils for the discovery of new antimicrobial drugs. This study has highlighted the antidermatophytic activity of the O. azureus EO.

Larvicidal activity of some Cerrado plant extracts against Aedes aegypti

One hundred ninety hexanic and ethanolic extract from 27 plant species from the Cerrado biome of Brazil were tested for larvicidal activity against 3rd-stage Aedes aegypti larvae at 500 microg/ml. Fourteen extracts from 7 species showed activity (>65% mortality) against the larvae. Of these Dugeutia furfuracea, Piptocarpha rotundifolia, Casearia sylvestris var. lingua, Serjania lethalis, and Xylopia aromatica were active at 56.6, 162.31, 232.4, 285.76, and 384.37 microg/ml, respectively. Annona crassiflora and Cybistax antisyphilitica showed activity at 23.06 and 27.61 microg/ml. The larvicidal properties of these species are described for the first time, and may prove to be promising in active chemical compound isolation.

Larvicidal activity of Cybistax antisyphilitica against Aedes aegypti larvae

The larvicidal activity against Aedes aegypti larvae of a stem wood hexane extract of Cybistax antisyphilitica was evaluated. Bioassay-guided fractionation of the crude extract, monitored by larvicidal assay, led to the isolation of a natural quinone identified as 2-hydroxy-3-(3-methyl-2-butenyl)-1.4-naphthoquinone (lapachol). This compound was quite potent against A. aegypti larvae (LC50 26.3 microg/ml).