Biomolecular analyses enable new insights into ancient Egyptian embalming.

The ability of the ancient Egyptians to preserve the human body through embalming has not only fascinated people since antiquity, but also has always raised the question of how this outstanding chemical and ritual process was practically achieved. Here we integrate archaeological, philological and organic residue analyses, shedding new light on the practice and economy of embalming in ancient Egypt. We analysed the organic contents of 31 ceramic vessels recovered from a 26th Dynasty embalming workshop at Saqqara1,2. These vessels were labelled according to their content and/or use, enabling us to correlate organic substances with their Egyptian names and specific embalming practices. We identified specific mixtures of fragrant or antiseptic oils, tars and resins that were used to embalm the head and treat the wrappings using gas chromatography-mass spectrometry analyses. Our study of the Saqqara workshop extends interpretations from a micro-level analysis highlighting the socio-economic status of a tomb owner3-7 to macro-level interpretations of the society. The identification of non-local organic substances enables the reconstruction of trade networks that provided ancient Egyptian embalmers with the substances required for mummification. This extensive demand for foreign products promoted trade both within the Mediterranean8-10 (for example, Pistacia and conifer by-products) and with tropical forest regions (for example, dammar and elemi). Additionally, we show that at Saqqara, antiu and sefet-well known from ancient texts and usually translated as 'myrrh' or 'incense'11-13 and 'a sacred oil'13,14-refer to a coniferous oils-or-tars-based mixture and an unguent with plant additives, respectively.

Applying multi-criteria analysis for preliminary assessment of the properties of alginate immobilized Myriophyllum spicatum in lake water samples.

The preliminary assessment of the properties of alginate immobilized aquatic weed Myriophyllum spicatum beads-MsAlg in a multi-element system of nine Serbian lakes water samples was done. Herein, the results obtained in the biosorption experiment with MsAlg contents of twenty-two elements analysed by inductively coupled plasma-optical emission spectrometry, biosorption capacity, element removal efficiency, total hardness (TH) and quality index of water (WQI) are presented. Scanning electron microscopy with energy dispersive X-ray spectroscopy was used for the characterization of M. spicatum and its beads. The study showed that aluminium, magnesium and strontium were adsorbed by MsAlg in the water samples from all examined lakes; barium and iron in the water samples from six lakes. The overall average efficiency of MsAlg in biosorption of elements was in the following order: Al > Ba > Sr > Fe > Mg (58.6, 51.7, 48.2, 23.9 and 17.7%, respectively). The increase of TH and WQI values after the biosorption was noticed in all studied lake water samples. The most significant correlations for pH were regarding the contents of B, Mg and Ca, whereas WQI was highly correlated to the contents of B and Mg, and pH. The complexity of the obtained data was explained by Cluster Analysis and Principal Component Analysis, which showed good discrimination capabilities between the water samples taken from different locations. Considering that the invasive M. spicatum is natural, widespread and that its immobilization is cheap and eco-friendly, presented findings could be helpful in further assessment of MsAlg beads for its potential use as biofilter.

Safety assessment of gasification biochars using Folsomia candida (Collembola) ecotoxicological bioassays.

Biochar is a product of the thermal decomposition of biomass under a limited supply of oxygen and can be deriving from pyrolysis or gasification. As the product is rich in highly recalcitrant carbon, it has been proposed as a soil amendment to improve soil fertility and to stock carbon in soils. However, the contaminant compounds present in biochar could represent potential environmental threats. The gasification biochar is a promising by-product, but its effects on soil microarthropods are still nearly unknown. The aim of this study was to assess, using a prognosis approach, any ecotoxicological consequences of four biochars (conifer, poplar, grape marc, and wheat straw) on the springtail Folsomia candida. This was assessed through a series of tests: an avoidance behavior test, a survival and reproduction test, and a test based on the hatching of eggs. Biochars were tested at different concentrations (pulverized and diluted w/w with an artificial standard soil). The results showed that the springtails did not tend to avoid the biochars' substrates up to the rate of 2-5%, but any higher levels of concentration caused the animals to keep away from it. While mortality was negatively affected only in the grape marc biochar, reproduction was significantly reduced in all biochars considered. The hatching of the eggs was anticipated at even the lowest concentrations of herbaceous biochars, while a severe delay was observed in both concentrations tested of the conifer biochar. The endpoints considered were negatively affected by pH, polycyclic aromatic hydrocarbons, and heavy metals (in order of importance). The findings confirmed the potential adverse effects that gasification biochars could have on soil microarthropods and demonstrated the necessity of introducing these tests into biochar characterization protocols.