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Kluyveromyces marxianus yeasts represent a valuable industry alternative due to their biotechnological potential to produce aromatic compounds. 2-phenylethanol and 2-phenylethylacetate are significant aromatic compounds widely used in food and cosmetics due to their pleasant odor. Natural obtention of these compounds increases their value, and because of this, bioprocesses such as de novo synthesis has become of great significance. However, the relationship between aromatic compound production and yeast's genetic diversity has yet to be studied. In the present study, the analysis of the genetic diversity in K. marxianus isolated from the natural fermentation of Agave duranguensis for Mezcal elaboration is presented. The results of strains in a haploid and diploid state added to the direct relationship between the mating type locus MAT with metabolic characteristics are studied. Growth rate, assimilate carbohydrates (glucose, lactose, and chicory inulin), and the production of aromatic compounds such as ethyl acetate, isoamyl acetate, isoamyl alcohol, 2-phenylethyl butyrate and phenylethyl propionate and the diversity in terms of the output of 2-phenylethanol and 2-phenylethylacetate by de novo synthesis were determinate, obtaining maximum concentrations of 51.30 and 60.39 mg/L by ITD0049 and ITD 0136 yeasts respectively. [ABSTRACT FROM AUTHOR]

Nanostructures of noble metals are being investigated for their applications in areas of biology and biotechnology, biological labeling, photothermal, photonics, optoelectronics, catalysis, surface-enhanced Raman scattering (SERS) detection etc. Among the metal nanoparticles, silver nanoparticles are well known for their size dependent properties as well as antibacterial activities. Pulsed laser ablation in liquid (PLAL) is a physical synthesis technique to obtain ultra-pure nanoparticles of metals, semiconductors and ceramics which is a green synthesis compared to other chemical methods. In this chapter, we describe antifungal activities of silver nanoparticles produced by pulsed laser ablation of a high purity silver target in distilled water. The chapter includes details of the synthesis of silver nanocolloids using PLAL and their characterization using various techniques. Antifungal activities of these silver nanocolloids on fungi such as Aspergillus niger and Penicillium spp are explained. These filamentous fungi are responsible for the deterioration of storage life of fruits and vegetables worldwide. The effects of heterogeneous shaped silver nanoparticles produced by PLAL in these two fungal species probed in vitro are discussed. The nanoparticle concentrations from 31.8 to 74.2 mg/L were able to delay mycelium growth and sporulation in both species at the conditions probed. These results open up more biological applications of nanoparticles synthesized by PLAL. [ABSTRACT FROM AUTHOR]