Juliana Ferreira Soares

Thermochemical processes for biofuels production from biomass

The contribution of biomass to the world’s energy supply is presently estimated to be around 10% to 14%. The conversion of biomass to biofuels can be achieved primarily via biochemical and thermochemical processes. Recently, the use of thermochemical processes as pyrolysis and gasification has received great attention. The biomass composition and form of process conduction can affect greatly the efficiency of conversion for both gasification and pyrolysis. This review compiles recent thermochemical studies using several kinds of biomass to obtain biofuels and, additionally, it presents a brief description of main gasification and pyrolysis processes employed. Publications in Patent database also were reported and compiled.

Concentration of metabolites from Phoma sp. using microfiltration membrane for increasing bioherbicidal activity

ABSTRACT This study is focused on the concentration of fermented broth from Phoma sp. to increase its herbicidal activity. For this purpose, biomolecules produced by submerged fermentation using Phoma sp. were concentrated by hollow fiber microfiltration membranes. The membrane feed was separated into two streams (retentate and permeate) and the crude broth was concentrated to 10, 30, 50, 70 and 90% (relative to the initial volume). The retentate samples were submitted to bioassays (triplicate) for evaluating their phytotoxic effects on five young leaves of species of Cucumis sativus and also on pre-emergence of weeds as Bidens pilosa and Amaranthus retroflexus. The highest herbicidal activity was 80.7% obtained for a concentration of 30% in the retentate fraction. At this condition, the bioherbicide presented severe damage symptoms on the detached leaves of Cucumis sativus if compared to the crude fermented broth. In the pre-emergence of B. pilosa and A. retroflexus, 100% control was obtained for assays performed in a germination chamber. For greenhouse assays using the substrate, the control rate of A. retroflexus was dependent of concentration of bioherbicide. The promising results achieved in the research with membrane separation process allow us to propose and develop further studies for evaluating this technology in the concentration of other metabolites produced by fermentation which also have bioherbicidal activity. GRAPHICAL ABSTRACT

Extracts from Lupinus albescens: antioxidant power and antifungal activity in vitro against phytopathogenic fungi

ABSTRACT Fungi are considered the most damaging microorganisms in agriculture. The indiscriminate use of chemical treatments in agricultural products causes the development of pest resistance and affects human health. An alternative to synthetic fungicides is the use of natural products such as plant extracts for the management of fungal diseases in plants. Extracts from different parts of Lupinus albescens (roots, stalks, leaves, and flowers) were obtained by extraction using supercritical carbon dioxide (CO2) or compressed liquefied petroleum gas (LPG). Thereafter, the antioxidant activity of each extract was measured, and the antifungal activity in vitro of extracts was evaluated against Fusarium oxysporum and Fusarium verticillioides. For a concentration of 5000 mg/L, the half maximal inhibitory concentration (IC50) ranged from 29.25 μg/mL to 192.96 μg/mL. Antifungal tests showed that all matrices presented inhibitory effect against both fungi tested. The extracts obtained from roots by CO2 and LPG presented 70.1% and 65.1% inhibition against F. oxysporum, and 67.8% and 61.2% inhibition against F. verticillioides, respectively. These results suggest that the extracts obtained from L. albescens by extractions using supercritical CO2 and compressed LPG might be a potential source of antioxidants and natural fungicides.

Cellulases for Food Applications

Abstract Enzymes are important additives in the food industry with a wide range of applications. Cellulases are used in different food processing units, thus presenting a fundamental role in improving the extraction and clarification of fruit and vegetable juices; improving cloud stability and texture, and decreasing viscosity of nectars and purees from tropical fruits; improving extraction of olive oil; and altering the texture, flavor, and other sensory properties such as aroma and volatile characteristics of fruits and vegetables. In this way, this chapter presents the state-of-the-art of the applications of cellulase in the food industry, focusing on the mentioned topics.

CHARACTERIZATION OF BIOLOGICAL FLOC AND MICROFAUNA IN ACTIVATED SLUDGE SYSTEM

The microscopic investigation of the floc and the microfauna present in the sludge is an important indicator of the performance and efficiency of the activated sludge system. Given this importance, the study aimed to characterize the structure of the biological flocs and identify the organisms that make up the microfauna in the aeration tanks from the industrial WWTP, relating to the physico-chemical parameters and process efficiency. For the characterization of floc and microfauna qualitative microscopic technique was employed. The physical-chemical parameters were supplied by industry’s own laboratory. During the study were observed groups of testate amoebae, rotifers, attached ciliates and ciliates free natantes characterizing the process with good purification and as the structure of the flocs between ideal and filamentous bulking. Qualitative analysis of biological floc structure proved important for the identification of cases of the filamentous bulking.