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Nowadays, hydrogen produced globally has been synthesized from fossil fuel with limited source. Therefore, research has been developed in order to explore biological H2 production by dark fermentation. The purpose of this work was to evaluate the effect of initial pH and ferrous sulfate and ammonium sulfate concentrations on the production of biohydrogen by dark fermentation. The process was carried out in batch mode under anaerobic conditions, in the absence of light, and at standard room temperature and pressure. A microbial consortium provided by the effluent treatment plant of a local dairy company was inoculated into a synthetic medium supplemented with cheese whey permeate (20 g/L of lactose) as a carbon source. The influence of three variables was analyzed by a central composite design 2((3)), and the optimum results of hydrogen yield (4.13 mol H2/mol lactose) and productivity (86.31 mmol H2/L/day) were achieved at initial pH 7.0 and FeSO4 and (NH4)2SO4 concentrations of 0.6 and 1.5 g/L, respectively. Under these conditions, the kinetic parameters of fermentation were investigated by analyzing the profile of H2 yield and productivity, metabolite concentrations, pH, and concentration of dissolved iron. In the kinetic analysis, the modified Gompertz equation described adequately the fermentative hydrogen production from cheese whey permeate (R (2) = 0.98). The profile of ethanol and volatile organic acids showed that lactic acid and butyric acid were the main metabolites produced, and the sum of both by-products corresponded to about 58 % of the total metabolites.

An animal protein-free medium was developed for Drosophila melanogaster S2 (S2Ac-GPV2) cells genetically modified to produce the rabies virus G glycoprotein (GPV). IPL-41, used as a basal medium, was supplemented with yeastolate, carbohydrates, amino acids and lipids aiming initially to reduce and further to eliminate the need of fetal bovine serum. The S2AcGPV2 cells were fully capable of growing in serum-free supplemented IPL-41 medium containing 6 g L -1 yeastolate ultrafiltrate, 10 g Lmethionine and 1% (v/v) lipid emulsion, reaching 19 9 10 6 cells mL -1 . Maximum specific growth rate and cell productivity were 0.025 h -1 and 0.57 9 10 5 cells mL, respectively. Glucose and lactose were consumed during cell culture, but not fructose. Lactate concentration generally decreased during cell culture, while ammonium concentration reached 167 mg L -1 , however, without noticeable deleterious effects on cell growth. GPV concentration values achieved were, however, modest in the proposed medium formulation.

Animal cells can be cultured both in basal media supplemented with fetal bovine serum (FBS) and in serum-free media. In this work, the supplementation of Grace's medium with a set of nutrients to reduce FBS requirements in Spodoptera frugiperda (Sf9) cell culture was evaluated, aiming the production of Anticarsia gemmatalis nucleopolyhedrovirus (AgMNPV) at a cost lower than those for the production using Sf900 II medium. In Grace's medium supplemented with glucose, Pluronic F68 (PF68) and yeast extract (YE), the effects of FBS and milk whey ultrafiltrate (MWU) on cell concentration and viability during midexponential and stationary growth phase were evaluated. In spite of the fact that FBS presented higher statistical effects than MWU on all dependent variables in the first cell passage studies,