Abstract-Fungal microorganisms are widely studied in the bioconversion of substrates. Among them, Pleurotus sajor-caju is well recognized for its known ability to colonize and degrade wastes through solid state bioprocess (SSB). Fruit residues are inexpensive substrates that present characteristics favorable for microorganisms' colonization. The aim of this work was to investigate the mycelial growth of P. sajor-caju on pequi and guavira fruit wastes through SSB, in order to valorize these residues by their biotransformation. Cultivations were carried out with the substrates at pH 5 and with 60% moisture in an incubator at 30 °C for 25 days. Microbiological analyzes for fungi and bacteria beyond proximate composition of the substrates were evaluated every 5 days. It was observed that P. sajor-caju reached maximum growth at the 15 th day in guavira waste and at the 25 th day in pequi waste. The protein enrichments obtained were 30.31% and 37.20% for guavira and pequi wastes, respectively. It was concluded that guavira favored microbial growth and protein concentration, presenting a final product very rich in protein with potential application for animal nutrition.Index Terms-Brazilian savannah, fungi, residues, kinetic.

Microorganisms are effective platforms for the production of a variety of chemicals including biofuels, commodity chemicals, polymers and other natural products. However, deep cellular understanding is required for improvement of current biofuel cell factories to truly transform the Bioeconomy. Modifications in microbial metabolic pathways and increased resistance to various types of stress caused by the production of these chemicals are crucial in the generation of robust and efficient production hosts. Recent advances in systems and synthetic biology provide new tools for metabolic engineering to design strategies and construct optimal biocatalysts for the sustainable production of desired chemicals, especially in the case of ethanol and fatty acid production. Yeast is an efficient producer of bioethanol and most of the available synthetic biology tools have been developed for the industrial yeast Saccharomyces cerevisiae. Non-conventional yeast systems have several advantageous characteristics that are not easily engineered such as ethanol tolerance, low pH tolerance, thermotolerance, inhibitor tolerance, genetic diversity and so forth. Currently, synthetic biology is still in its initial steps for studies in non-conventional yeasts such as Yarrowia lipolytica, Kluyveromyces marxianus, Issatchenkia orientalis and Pichia pastoris. Therefore, the development and application of advanced synthetic engineering tools must also focus on these underexploited, non-conventional yeast species. Herein, we review the basic synthetic biology tools that can be applied to the standard S. cerevisiae model strain, as well as those that have been developed for non-conventional yeasts. In addition, we will discuss the recent advances employed to develop non-conventional yeast strains that are efficient for the production of a variety of chemicals through the use of metabolic engineering and synthetic biology.

Due to the amount of nutrients available in the agroindustrial wastes, these can be converted into high added-value products by the action of microorganisms in solid-state bioprocesses. The aim of this work was to evaluate the growth physiology and lipase production of the fungus Lichtheimia ramosa using the following Brazilian savannah fruit wastes as substrates: bocaiuva (Acrocomia aculeata), pequi (Caryocar brasiliense), guavira (Campomanesia pubescens), araticum (Annona crassiflora) and seriguela (Spondias purpurea). These residues were triturated, homogenized, adjusted to pH 5.0 and 60 % moisture, sterilized and packaged in plastic tray-type bioreactors before inoculation with 10 % (w/v) of L. ramosa pre-culture medium. The cultivations were conducted in a bacteriological incubator at 30 °C for 40 days. Samples were taken every 5 days and fungi and bacteria contents, proximate composition and lipase activity were evaluated. The maximum fungal counting was observed between 25 and 35 days. L. ramosa reached the stationary phase next to 40 days in all substrates. Mesophilic and psicrophilic aerobic bacteria were not detected. Protein enrichment was obtained for all media, being superior in seriguela residues (391.66 %), followed by pequi (160.04 %), araticum (143.31 %), guavira (102.42 %), and bocaiuva (67.88 %). Lipase production was observed in all cultivated media, except in pequi residues that showed decreasing lipase activity. The higher production was observed in guavira (1.12 U/g) followed by araticum (0.58 U/g), seriguela (0.41 U/g) and bocaiuva (0.21 U/g) waste substrates. It was concluded that the studied fruit wastes have been successfully utilized as substrates for protein enrichment and lipase production with L. ramosa.

Background: Enzyme production by solid state bioprocess (SSB) using residues as substrate for microorganisms is an alternative for costs reduction and to avoid their disposal into environment. The aim of this work was to evaluate the physiology of the fungus Lichtheimia ramosa in terms of microbial growth and production of amylases, β-glucosidases, carboxymethylcellulase (CMCase), and xylanases, via SSB, utilizing wastes of the Brazilian savannah fruits bocaiuva (Acrocomia aculeata), guavira (Campomanesia pubescens) and pequi (Caryocar brasiliense) as substrate at different temperatures (25, 30, and 35ºC) during 168 hrs. Results: Samples were taken every 24 hrs, which resulted in 8-points kinetic experiments to determine microbiological and enzymatic contents. The best substrate for β-glucosidase activity was pequi waste after 48 hrs at 30ºC (0.061 U/mL). For amylase activity, bocaiuva presented itself as the best substrate after 96 hrs at 30ºC (0.925 U/mL). CMCase activity was higher in guavira waste after 96 hrs at 35ºC (0.787 U/mL). However, the activity was more expressive for xylanase in substrate composed of bocaiuva residue after 144 hrs at 35ºC (1.802 U/mL). Conclusions: It was concluded that best growth condition for L. ramosa is at 35ºC for all substrates and that xylanase is the enzyme with more potential in SSB, considering the studied Brazilian savannah fruit wastes.

No abstract