Culturing the desert microbiota

Over the last 30 years, the description of microbial diversity has been mainly based on culture-independent approaches (metabarcoding and metagenomics) allowing an in-depth analysis of microbial diversity that no other approach allows. Bearing in mind that culture-dependent approaches cannot replace culture-independent approaches, we have improved an original method for isolating strains consisting of "culturing" grains of sand directly on Petri dishes (grain-by-grain method). This method allowed to cultivate up to 10% of the bacteria counted on the surface of grains of the three sites studied in the Great Western Erg in Algeria (Timoudi, Béni Abbès, and Taghit), knowing that on average about 10 bacterial cells colonize each grain. The diversity of culturable bacteria (collection of 290 strains) predicted by 16S rRNA gene sequencing revealed that Arthrobacter subterraneus, Arthrobacter tecti, Pseudarthrobacter phenanthrenivorans, Pseudarthrobacter psychrotolerans, and Massilia agri are the dominant species. The comparison of the culture-dependent and -independent (16S rRNA gene metabarcoding) approaches at the Timoudi site revealed 18 bacterial genera common to both approaches with a relative overestimation of the genera Arthrobacter/Pseudarthrobacter and Kocuria, and a relative underestimation of the genera Blastococcus and Domibacillus by the bacterial culturing approach. The bacterial isolates will allow further study on the mechanisms of tolerance to desiccation, especially in Pseudomonadota (Proteobacteria).

Could EU herbal monographs contribute to Malta's treatment armamentarium?

Ten years have passed since Directive 2004/24/EC regulating herbal medicinal products across the EU were published. The directive created the Committee on Herbal Medicinal Products within the European Medicines Agency whose remit includes the creation and publishing of official EU monographs on herbal medicinal products. These monographs include the official uses of the products and their evidence for efficacy and safety. To this effect, we are interested in analysing the potential impact herbal product EU monographs could have on the therapeutic treatment options available for prescribers in Malta. Therefore our aim was two-fold. First, to rationalise the spread of indications of the herbal substances listed in the community herbal monograph inventory and subsequently determine if these herbal substances could potentially contribute to the treatment options available in our local scenario (Malta). 128 EU monographs were analysed resulting in a total of 230 indications which subsequently codified into 42 unique ATC codes. The Malta Medicines List contains 1456 unique ATC codes. Comparative analysis of the Malta Medicines List revealed that the 21 therapeutic areas had 4 or less pharmaceutically used substances (5th level ATC codes) registered and therefore in our opinion are areas with limited therapeutic choice. The following 4 therapeutic areas, A05 bile and liver therapy, A13 tonics, A15 appetite stimulants and D03 preparations for treatment of wounds and ulcers, could potentially benefit from the registration of herbal medicinal products according to the EU herbal monographs. If such registration is effected the aforementioned areas would no longer be considered limited because more than 4 therapeutic choices would be available to prescribers. This study is the first study across the EU to analyse the potential impact of published EU herbal monographs on therapeutic coverage in an EU member state and confirms the notion that herbal products could potentially increase the treatment options available in areas where few medical products have been registered due to Malta's small market size.

Immunomodulatory activity of cucurbitacin E isolated from Ecballium elaterium

The immunomodulatory effect of cucurbitacin E, extracted from Ecballium elaterium, was tested on peripheral human lymphocytes. These lymphocytes were co-cultured with cancer cells and an interesting lymphocyte-mediated cytotoxicity was observed.