Beneficial modulation of the gut microbiome by leachates of Penicillium purpurogenum in the presence of clays: A model for the preparation and efficacy of historical Lemnian Earth.

The experiments presented here are based on the reconfiguration of an ancient medicine, Lemnian Earth (LE) (terra sigillata, stamped earth, sphragis), an acclaimed therapeutic clay with a 2500-year history of use. Based on our hypothesis that LE was not a natural material but an artificially modified one involving a clay-fungus interaction, we present results from experiments involving the co-culture of a common fungus, Penicillium purpurogenum (Pp), with two separate clay slurries, smectite and kaolin, which are the principal constituents of LE. Our results show: (a) the leachate of the Pp+smectite co-culture is antibacterial in vitro, inhibiting the growth of both Gram-positive and Gram-negative bacteria; (b) in vivo, supplementation of regular mouse diet with leachates of Pp+smectite increases intestinal microbial diversity; (c) Pp+kaolin does not produce similar results; (d) untargeted metabolomics and analysis of bacterial functional pathways indicates that the Pp+smectite-induced microbiome amplifies production of short-chain fatty acids (SCFAs) and amino acid biosynthesis, known to modulate intestinal and systemic inflammation.

The ecology and bioactivity of some Greco-Roman medicinal minerals: the case of Melos earth pigments.

Mineral compounds, as pigments and therapeutics, appeared regularly in the technical and medical texts of the Greco-Roman (G-R) world. We have referred to them as 'G-R medicinal minerals' and we suggest that despite their seeming familiarity, there are actually many unknowns regarding their precise nature and/or purported pharmacological attributes. Earth pigments are part of that group.

analysing psimythion (synthetic cerussite) pellets (5th-3rd centuries BCE) and hypothesising gas-metal reactions over a fermenting liquid within a Greek pot.

A Pb-based synthetic mineral referred to as (pl. ) was manufactured in the Greek world at least since the 6th c BCE and routinely by the 4th c BCE. Theophrastus () describes its preparation from metallic Pb suspended over a fermenting liquid.

Bridging the Gaps: Bole and Terra Sigillata as Artefacts, as and as Antibacterial Clays.

Medicinal earths are an important and yet, so far, little scientifically explored archaeological resource. They are almost always identified by their source locality. Our work over the last few years has focused on their chemical and mineralogical characterization and their testing as anti-bacterials.

The interweaving roles of mineral and microbiome in shaping the antibacterial activity of archaeological medicinal clays.

Ethnopharmacological Relevance: Medicinal Earths (MEs), natural aluminosilicate-based substances (largely kaolinite and montmorillonite), have been part of the European pharmacopoeia for well over two millennia; they were used generically as antidotes to 'poison'.

Aim Of The Study: To test the antibacterial activity of three Lemnian and three Silesian Earths, medicinal earths in the collection of the Pharmacy Museum of the University of Basel, dating to 16th-18th century and following the methodology outlined in the graphical abstract. To compare them with natural clays of the same composition (reference clays) and synthetic clays (natural clays spiked with elements such as B, Al, Ti and Fe); to assess the parameters which drive antibacterial activity, when present, in each group of samples.