The purpose of this paper is to provide a brief review of the current state of our knowledge regarding pesticides and oxidative stress. To this end, we performed a search of the literature using Medline/Index Medicus, EMBASE/Excerpta Medica, and Chemical Abstracts; most of the relevant citations were studied and summarized. In order to better understand the nature of oxidative stress, the principles of free radical production and the body's normal defense system are discussed. The pesticides are categorized and discussed according to their ability to produce lipid peroxidation or alter body antioxidant status. It is concluded that stimulation of free radical production, induction of lipid peroxidation, and disturbance of the total antioxidant capability of the body are mechanisms of toxicity in most pesticides, including organophosphates, bipyridyl herbicides and organochlorines.

Pesticides and oxidative stress: a review.

Agricultural residues are rich in bioactive compounds. These residues can be used as an alternate source for the production of different products like biogas, biofuel, mushroom, and tempeh as the raw material in various researches and industries. The use of agro-industrial wastes as raw materials can help to reduce the production cost and also reduce the pollution load from the environment. Agro-industrial wastes are used for manufacturing of biofuels, enzymes, vitamins, antioxidants, animal feed, antibiotics, and other chemicals through solid state fermentation (SSF). A variety of microorganisms are used for the production of these valuable products through SSF processes. Therefore, SSF and their effect on the formation of value-added products are reviewed and discussed.

/pdf/agro-industrial-wastes-and-their-utilization-using-solid-419ao2hw4h.pdf

Agro-industrial wastes and their utilization using solid state fermentation: a review

Olive mill wastes: Biochemical characterizations and valorization strategies

Strains belonging to the yeast species Kluyveromyces marxianus have been isolated from a great variety of habitats, which results in a high metabolic diversity and a substantial degree of intraspecific polymorphism. As a consequence, several different biotechnological applications have been investigated with this yeast: production of enzymes (β-galactosidase, β-glucosidase, inulinase, and polygalacturonases, among others), of single-cell protein, of aroma compounds, and of ethanol (including high-temperature and simultaneous saccharification-fermentation processes); reduction of lactose content in food products; production of bioingredients from cheese-whey; bioremediation; as an anticholesterolemic agent; and as a host for heterologous protein production. Compared to its congener and model organism, Kluyveromyces lactis, the accumulated knowledge on K. marxianus is much smaller and spread over a number of different strains. Although there is no publicly available genome sequence for this species, 20% of the CBS 712 strain genome was randomly sequenced (Llorente et al. in FEBS Lett 487:71–75, 2000). In spite of these facts, K. marxianus can envisage a great biotechnological future because of some of its qualities, such as a broad substrate spectrum, thermotolerance, high growth rates, and less tendency to ferment when exposed to sugar excess, when compared to K. lactis. To increase our knowledge on the biology of this species and to enable the potential applications to be converted into industrial practice, a more systematic approach, including the careful choice of (a) reference strain(s) by the scientific community, would certainly be of great value.

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The yeast Kluyveromyces marxianus and its biotechnological potential.

This review paper provides an overview regarding the main aspects of microbial lipases production. The most important microbial lipase-producing strains for submerged and solid-state fermentations are reviewed as well as the main substrates, including the use of agroindustrial residues. Current process techniques (batch, repeated-batch, fed-batch, and continuous mode) are discussed and the main bioreactors configurations are also presented. Furthermore, the present review paper shows a general overview about the development of mathematical models applied to lipase production. Finally, some future perspectives on lipase production are discussed with special emphasis on lipase engineering and the use of mathematical models as a useful tool for process improvement and control.

A Review on Microbial Lipases Production

A microtiter plate adaptation of the well-known dinitrosalicylic acid (DNS) colorimetric method, for measurement of reducing sugars, is described. This method allows a substantial volume reduction of the reagents and a rapid analysis of a large number of samples, having an economic cost benefit and a positive impact on the environment. Therefore, it is well suited as an high-throughput technique for reducing sugars determination.

/pdf/adaptation-of-dinitrosalicylic-acid-method-to-microtiter-cnpiy4xah7.pdf

Adaptation of dinitrosalicylic acid method to microtiter plates

Yarrowia lipolytica is one of the most extensively studied ‘‘non-conventional’’ yeasts, being a strictly aerobic microorganism capable of producing important metabolites and having an intense secretory activity, which justifies efforts to use it in industry (as a biocatalyst), in molecular biology and in genetics studies. Moreover, Y. lipolytica has been considered an adequate model for dimorphism studies in yeasts. Yarrowia lipolytica presents the ability to grow on Olive Mill Wastewater (OMW) as well as to degradate organic compounds, including aliphatic and aromatic hydrocarbons, often accompanied by biosurfactants production. One of the most important products secreted by this microorganism is lipase which can be exploited for several applications in the detergent, food, pharmaceutical, and environmental industries. In addition, Y. lipolytica is able to produce citric acid and aroma from a variety of carbon sources, including sugars, alkanes, plant oils, starch hydrolysates, ethanol, and glycerol. Thus, this chapter presents an overview of Yarrowia lipolytica features and its major biotechnological applications.

/pdf/yarrowia-lipolytica-an-industrial-workhorse-1xki3un5j0.pdf

Yarrowia lipolytica: an industrial workhorse

The consumers’ demand for natural flavour and fragrances rises. To be natural, compounds have to result from the extraction of natural materials and/or to be transformed by natural means such as the use of enzymes or whole cells. Fungi are able to transform some fatty acids into lactones that can thus be natural. Although some parts of this subject have been reviewed several times, the present article proposes to review the different pathways utilised, the metabolic engineering strategies and some current concerns on the reactor application of the transformation including scaling up data. The main enzymatic steps are hydroxylation and β-oxidation in the traditional way, and lactone desaturation or Baeyer–Villiger oxidation. Although the pathway to produce γ-decalactone is rather well known, metabolic engineering strategies may result in significant improvements in the productivity. For the production of other lactones, a key step is the hydroxylation of fatty acids. Beside the biotransformation, increasing the production of the various lactones requires from biotechnologists to solve two main problems which are the toxicity of lactones toward the producing cell and the aeration of the emulsified reactor as the biochemical pathway is very sensitive to the level of available oxygen. The strategies employed to resolve these problems will be presented.

Biochemistry of lactone formation in yeast and fungi and its utilisation for the production of flavour and fragrance compounds

https://repositorium.sdum.uminho.pt/bitstream/1822/9714/1/Goncalves_BioresTechnol%5b1%5d.pdf

Biological treatment of olive mill wastewater by non-conventional yeasts.

https://repositorium.sdum.uminho.pt/bitstream/1822/41778/1/document_38974_1.pdf

Isabel Belo

Papers

Adaptation of dinitrosalicylic acid method to microtiter plates

Yarrowia lipolytica: an industrial workhorse

Biochemistry of lactone formation in yeast and fungi and its utilisation for the production of flavour and fragrance compounds

Biological treatment of olive mill wastewater by non-conventional yeasts.

Ultrasounds pretreatment of olive pomace to improve xylanase and cellulase production by solid-state fermentation.