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The study aims to develop a full-scale plant to produce yeast biodiesel from cardoon stalks, based on the biorefinery concept, and to evaluate its environmental burden using a cradle-to-gate, scaled-up LCA approach. The results identified the following environmental hotspots all over the whole chain: the production of enzymes required in the hydrolysis of steam-exploded biomass and the heat and organic solvents required for lipid extraction and the subsequent distillation steps. The analysis of the LCA normalization results revealed that the highest environmental burdens were associated with human carcinogenic toxicity (69.2%). A further interesting result was that the GHG emissions associated to yeast biodiesel are negative (−1.5 g CO2 eq/MJ), due to the environmental credits generated by the co-products. Comparison with other biodiesel sources were also carried out showing that yeast biodiesel from cardoon stalks has the potential to become a competitive alternative from an environmental perspective.

Stranded driftwood feedstocks may represent, after pretreatment with steam explosion and enzymatic hydrolysis, a cheap C-source for producing biochemicals and biofuels using oleaginous yeasts. The hydrolysis was optimized using a response surface methodology (RSM). The solid loading (SL) and the dosage of enzyme cocktail (ED) were variated following a central composite design (CCD) aimed at optimizing the conversion of carbohydrates into lipids (YL) by the yeast Solicoccozyma terricola DBVPG 5870.A second-order polynomial equation was computed for describing the effect of ED and SL on YL.The best combination (ED = 3.10%; SL = 22.07%) for releasing the optimal concentration of carbohydrates which gave the highest predicted YL (27.32%) was then validated by a new hydrolysis. The resulting value of YL (25.26%) was close to the theoretical maximum value.Interestingly, fatty acid profile achieved under the optimized conditions was similar to that reported for palm oil. Keywords: Stranded driftwood feedstocks, Solicoccozyma terricola, Enzymatic hydrolysis, Yeast biochemicals and biofuels, Response surface methodology

Due to the increasing consumer demand, the production of low alcoholic and non alcoholic beer is the new goal of the present brewing producers. Although the beer with reduced alcohol content is currently obtained by physical methods, the use of non-Saccharomyces yeast, with low fermentations capacities, may represent an interesting biological approach. In this study the ethanol content and the volatile profile of a beer obtained using the basidiomycetous psychrophilic yeast strain Mrakia gelida DBVPG 5952 was compared with that produced by a commercial starter for low alcohol beers, Saccharomycodes ludwigii WSL17. The two beers were characterized by a low alcohol content (1.40% and 1.32% v/v) and by a low diacetyl production (5.04 and 5.20 μg/L). However, the organoleptic characteristics of the beer obtained using M. gelida are more appreciated by the panelists, in comparison to the analogous produced with the commercial strain of S. ludwigii.

The rising consumer demand for “natural” foodstuffs has encouraged a growing part of both the academic and industrial scientific communities to develop novel biocatalysts for producing flavoring molecules. In this context, nonconventional yeasts (NCYs) have attracted increasing interest due to their biochemical characteristics and potential applications, being able to produce aroma compounds from a variety of carbon sources, including sugars, alkanes, plant oils, starch hydrolysates, ethanol, and glycerol. Apart from classical fermentation processes (de novo synthesis), bioconversion of appropriate precursor compounds are also being developed to produce food aromas. An overview on the potential of NCYs’ whole cell for producing food flavors by biotransformation is illustrated in this chapter by a discussion of the production of different class of compounds, namely alcohols, aldehydes, ketones, lactones, terpenes, and terpenoids, alkenes, phenols, and sulfur compounds.

Background: Some lignocellulosic biomass feedstocks occur in Mediterranean Countries. They are still largely unexploited and cause considerable problems due to the lack of cost-effective harvesting, storage and disposal technologies. Recent studies found that some basidiomycetous yeasts are able to accumulate high amount of intracellular lipids for biorefinery processes (i.e., biofuels and biochemicals). Accordingly, the above biomass feedstocks could be used as carbon sources (after their pre-treatment and hydrolysis) for lipid accumulation by oleaginous yeasts. Results: Cardoon stalks, stranded driftwood and olive tree pruning residues were pre-treated with steam-explosion and enzymatic hydrolysis for releasing free mono- and oligosaccharides. Lipid accumulation tests were performed at two temperatures (20 and 25 °C) using Leucosporidium creatinivorum DBVPG 4794, Naganishia adeliensis DBVPG 5195 and Solicoccozyma terricola DBVPG 5870. S. terricola grown on cardoon stalks at 20 °C exhibited the highest lipid production (13.20 g/l), a lipid yield (28.95%) close to the maximum theoretical value and a lipid composition similar to that found in palm oil. On the contrary, N. adeliensis grown on stranded driftwood and olive tree pruning residues exhibited a lipid composition similar to those of olive and almonds oils. A predictive evaluation of the physical properties of the potential biodiesel obtainable by lipids produced by tested yeast strains has been reported and discussed. Conclusions: Lipids produced by some basidiomycetous yeasts grown on Mediterranean lignocellulosic biomass feedstocks could be used as supplementary sources of oils for producing biofuels and biochemicals. © 2018 The Author(s).

In the last years, the increased sensitivity of a new generation of STR kits has contributed to a stronger focus on the issue of contamination. DNA contamination can occur by either direct or indirect transfer. Direct transfer includes contact, but also activities within the vicinity of an item that may result in the transfer of DNA from an individual without any contact (speaking or coughing). Indirect transfer of DNA is when DNA from an individual comes to be on an item via an intermediary surface. Contamination within the laboratory may occur as a result of unprotected speaking, through the presence of DNA on unused laboratory gloves, and ineffective cleaning procedures. A recent study noted the transfer of dried blood from and to cotton via tools used during examination (scissors, forceps and gloves), and indicated that these instruments pose a high contamination risk if they are not adequately cleaned. In our work, we analyzed all the gloves used in one day by four operators working in our laboratory. For every glove, we evaluated the presence of contamination DNA from the operator or from other samples. The results are presented here. In forensic caseworks, it is imperative to change gloves every time after touching items or surfaces, prior to touching the exhibit. It is desirable to wear multiple layers of gloves to avoid skin exposure during the changing of gloves.

Yeasts play a relevant role as starter cultures in traditional foods and beverages, as well as in innumerable biotechnological applications for obtaining high-value bulk and fine biochemicals. Despite a considerable number of studies on yeasts have been performed by using almost exclusively the species Saccharomyces cerevisiae (otherwise labeled as baker’s yeast), the number of yeast species described so far accounts for more than 1600, belonging to over 130 ascomycetous and basidiomycetous genera. This huge yeast diversity includes many non-Saccharomyces species possessing useful, and sometimes uncommon, metabolic features potentially interesting for both food and nonfood industries. Like other organisms, cold-adapted yeasts include species able to survive and grow in cold environments. They are usually labeled as psychrophiles or psychrotolerants on the basis of their cardinal growth temperatures. Among them, yeasts belonging to the phylum Basidiomycota apparently exhibit a superior adaptation to cold. This apparent superiority, which could be the result of some metabolic strategies implemented for adapting life to different thermal conditions in order to overcome the adverse effect of cold, can be considered worthwhile for implementing their biotechnological application at low temperatures. Accordingly, cold-adapted basidiomycetous yeasts have attracted considerable attention for their biotechnological potential, because they have developed the ability to synthesize cold-active enzymes, as well as other important biochemicals, namely, cryoprotectant compounds, polymers, lipids, and other miscellaneous compounds.

The main terrestrial cold areas (outside Antarctica and the Arctic and subarctic regions, viz., the Earth strip running approximately between 60°N and 60°S) are those covered by glaciers and permafrost soil, primarily confined in the Himalayas, Andes, and European high mountains and only little portions in other parts of the globe.

Background The ability of some microorganisms to accumulate lipids is well known; however, only recently the number of studies on microbial lipid biosynthesis for obtaining oleochemical products, namely biofuels and some building blocks for chemistry, is rapidly and spectacularly increased. Since 1990s, some oleaginous yeasts were studied for their ability to accumulate lipids up to 60–70% of their dry weight. Due to the vast array of engineering techniques currently available, the recombinant DNA technology was the main approach followed so far for obtaining lipid-overproducing yeasts, mainly belonging to the Yarrowia lipolytica. However, an alternative approach can be offered by worldwide diversity as source of novel oleaginous yeasts. Lipogenic aptitude of a number of yeast strains has been reviewed, but many of these studies utilized a limited number of species and/or different culture conditions that make impossible the comparison of different results. Accordingly, the lipogenic aptitude inside the yeast world is still far from being fully explored, and finding new oleaginous yeast species can acquire a strategic importance. Results Holtermanniella wattica, Leucosporidium creatinivorum, Naganishia adeliensis, Solicoccozyma aeria, and Solicoccozyma terricola strains were selected as a result of a large-scale screening on 706 yeasts (both Ascomycota and Basidiomycota). Lipid yields and fatty acid profiles of selected strains were evaluated at 20 and 25 °C on glucose, and on glycerol, xylose, galactose, sucrose, maltose, and cellobiose. A variable fatty acid profile was observed in dependence of both temperature and different carbon sources. On the whole, L. creatinivorum exhibited the highest performances: total lipid yield (YL) >7 g/l on glucose and glycerol, % of intracellular lipids on cell biomass (YL/DW) >70% at 20 °C on glucose, lipid coefficient (YL/Glu) around 20% on glucose, and daily productivity (YL/d) on glucose and sucrose >1.6 g/(l*d). Conclusions This study provides some meaningful information about the lipogenic ability of some yeast species. Variable lipid yields and fatty acid profiles were observed in dependence of both temperature and different carbon sources. L. creatinivorum exhibited the highest lipogenic performances. Electronic supplementary material The online version of this article (doi:10.1186/s13068-016-0672-1) contains supplementary material, which is available to authorized users.

In recent years new molecular biology techniques have emphasized changes in cancer research and important advances in genomic and proteomic fields have led to the need to develop tissue banks for research purpose. Since pathology departments must store tissue blocks for many years, the biomaterial stored in their archives can represent a very useful tool for research. However, the lack of specific laws and the absence of an explicit consensus to the use of these specimens for research purposes cause many difficulties. We must also notice that, sometimes, for these tissues it is particularly difficult to obtain an "a posteriori" consensus, because many subjects could be dead or unavailable. On May 1st 2012 “The Italian Privacy Authority” established that, when the involved person is unavailable or dead, this kind of samples can be used for research purposes without a consent or, as an alternative, in anonymous way. We would like to underlie both the importance of histopathology specimens in cancer research and the essential role of the pathologists because they are the only ones that can recognize and classify pathological tissues, ensure that the tissue removals for research projects do not compromise the diagnosis and the analysis of the resection margins

During the last years, DNA profiling techniques have become more sensitive and mixtures with multiple contributors occur often. Nevertheless, interpretation of mixture profiles is the most complex task in the forensic field. The ISFG published recommendations for the interpretation of mixed DNA profiles that may have allelic drop-out or drop-in. The DNA commission of the ISFG has supported the use of likelihood ratios (LRs) as preferable to other methods. LR can be calculated by probabilistic programs, using semi and fully continuous (probabilistic) methods. These methods increase the efficiency of forensic laboratories and improve the consistency and transparency of the reported results. LRmix is an open-source system dedicated to the interpretation of forensic DNA profiles with a particular focus on complex DNA mixtures. This software is programmed on a LR model and facilitates the calculation of LR for complex mixtures, with partial profiles with known and unknown contributors. Here, we report the re-analysis of two old complex cases processed in our laboratory in the last years. In both cases, we used the software LRmix Studio with interesting consequences: in one case we solved the crime, in the other one, the results allowed the case to be reopened.