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Wood species identification and characterization of its weathering processes are crucial steps in the scientific approach of conservation of wooden cultural heritage. Many precious wooden objects of ancient Egypt are largely present in museums, nevertheless relatively little information is available concerning the nature of timber used and on their status of conservation. To address this gap, the wooden species of three relevant archaeological wood objects (statue, box, and coffin) arising from different Egyptian archaeological sites dated from the Old Kingdom (2,686–2,181 BC) to New Kingdom (1,550–1,069 BC) were deeply studied. Five hardwood and softwood species were identified belonging to Tamarix mannifera, T. gennessarensis, Ficus sycomorus, Vachellia nilotica, and Cedrus sp. Such data confirmed the recurrence of Vachellia and Tamarix among the most common timbers found in ancient Egypt. Scanning electron microscope, Fourier transform spectroscopy, and synchrotron x‐ray radiation diffraction were conducted to evaluate the archaeological wood deterioration. The formation of microcracks, biological degradation patterns (fungal colonization), or chemical characterization (accumulation of salts on and in‐between wooden cells) were detected. SEM micrographs showed the presence of fungal hyphae and conidial spores on the wooden cells. Significant changes in the chemical wood composition and decrease in the crystallinity index were detected.

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Using high gravity fermentation for bioethanol production by Saccharomyces cerevisiae is faced with many challenges such as increasing osmotic stress and viscosity. Unfortunately, increasing specific gravity was accompanied by a decrease in fermentation efficiency. A two-stage sequential optimization strategy was carried out to solve this problem. The first stage was carried out using the Plackett-Burman Design in which eight factors were investigated at three molasses specific gravities (1.130, 1.145, 1.160). Urea, wheat bran, soy flour, and inoculum size were significant model terms and had positive effect on bioethanol production. When a validation test was performed using the predicted conditions, about a more than two-fold increase in fermentation efficiency (FE) was achieved (83%) at specific gravity 1.130, compared to the basal condition. The second stage (Taguchi Design) was conducted using eight factors. Urea, wheat bran, temperature, and agitation speed showed a significant effect on fermentation efficiency. A validation test was carried out and up to 83.82 % fermentation efficiency was recorded, which was very close to that achieved under normal gravity. In addition to the high value of FE, this strategy is cost-effective and time-saving.