Distinct Binding and Immunogenic Properties of the Gonococcal Homologue of Meningococcal Factor H Binding Protein

Neisseria meningitidis is a leading cause of sepsis and meningitis. The bacterium recruits factor H (fH), a negative regulator of the complement system, to its surface via fH binding protein (fHbp), providing a mechanism to avoid complement-mediated killing. fHbp is an important antigen that elicits protective immunity against the meningococcus and has been divided into three different variant groups, V1, V2 and V3, or families A and B. However, immunisation with fHbp V1 does not result in cross-protection against V2 and V3 and vice versa. Furthermore, high affinity binding of fH could impair immune responses against fHbp. Here, we investigate a homologue of fHbp in Neisseria gonorrhoeae, designated as Gonococcal homologue of fHbp (Ghfp) which we show is a promising vaccine candidate for N. meningitidis. We demonstrate that Gfhp is not expressed on the surface of the gonococcus and, despite its high level of identity with fHbp, does not bind fH. Substitution of only two amino acids in Ghfp is sufficient to confer fH binding, while the corresponding residues in V3 fHbp are essential for high affinity fH binding. Furthermore, immune responses against Ghfp recognise V1, V2 and V3 fHbps expressed by a range of clinical isolates, and have serum bactericidal activity against N. meningitidis expressing fHbps from all variant groups

Extraction of antioxidant compounds from Jabuticaba (Myrciaria cauliflora) skins: Yield, composition and economical evaluation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Obtaining an extract with high antioxidant activity using environmentally friendly technologies and low-cost raw materials is of great interest. In the present work, a combined extraction process developed by our research group involving ultrasound treatment and agitated solvent extraction was evaluated. This method was compared in terms of yield, composition, and economical feasibility to traditional extraction methods, including ultrasound assisted, agitated bed and soxhlet extraction with ethanol (acidified or not). The proposed method maximizes the extraction of phenolic compounds with acceptable degradation of anthocyanin pigments from an unusual source: Brazilian jabuticaba (Myrciaria cauliflora) skins. The use of ultrasonic irradiation continuously supporting a main extraction process has demonstrated increased performance but implies in high consumption of energy and consequently, money. However, the procedure described in this paper appears to be a viable option because it uses shorter ultrasonic irradiation and results in high antioxidant activity extracts, and the anthocyanin profile corroborates literature data (cyanidin-3-glucoside and delphinidin-3-glucoside). (C) 2010 Elsevier Ltd. All rights reserved.10112331Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPq [141894/2009-1]FAPESP [2008/10986-2

Optimization and economic evaluation of pressurized liquid extraction of phenolic compounds from jabuticaba skins

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The optimization of the extraction of anthocyanins and other phenolic compounds from jabuticaba skins, a promising Brazilian source of these compounds, was studied using pressurized liquid extraction (PLE). An optimization study was performed using ethanol as a solvent and with extraction pressure (510 MPa), temperature (313-393 K) and static extraction time (3-15 min) as independent variables. The optimum PLE conditions for all response variables were estimated; however, PLE conditions resulting in the highest recovery of anthocyanins (5 MPa, 553 K and 9 min of static extraction time) were chosen for comparison with a conventional low-pressure solvent extraction (LPSE). The attributes compared were yield, content of anthocyanins and phenolic compounds and economic feasibility. Similar extraction yields were obtained by LPSE and PLE under optimized conditions; however 2.15 and 1.66-fold more anthocyanins and total phenolic compounds, respectively, were extracted using PLE, while the cost of manufacturing (COM) obtained for the PLE extract was 40-fold lower. (C) 2011 Elsevier Ltd. All rights reserved.1083444452Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPq [141894/2009-1]FAPESP [2008/10986-2

Supercritical Fluid Extraction Of Lemon Verbena (sf Aloysia triphylla): Process Kinetics and Scale-Up, Extract Chemical Composition and Antioxidant Activity, and Economic Evaluation

The extract of lemon verbena ( Aloysia triphylla ) was obtained by supercritical fluid extraction (SFE) using laboratory and pilot scale equipments. The scale-up criterion selected (maintaining solvent to feed ratio constant) was successfully used for a 14-fold scale-up. The extract obtained in pilot scale was separated in three fractions, which were characterized as for their phytochemical profile, total flavonoids content, and antioxidant activity. The extracts obtained by SFE were compared to classical Soxhlet extraction method. Maximum yield obtained for SFE was 1.8%, and for Soxhlet, 7.1%. The chemical composition revealed different phytochemical profiles for SFE and Soxhlet extracts; the last ones presented more flavonoids, while SFE extracts were more concentrated in volatile compounds. The major compounds identified in the volatile fraction of the extracts were spathulenol, phytol and octadecatrienal. Some extracts presented pro-oxidant activity and others presented antioxidant activity. The SFE process was shown to be economically feasible for obtaining lemon verbena extracts; the minimum manufacturing cost (COM) obtained was US$ 1070.00/kg, with a payback time of 2 years.49456957

Production of phenolic-rich extracts from Brazilian plants using supercritical and subcritical fluid extraction: Experimental data and economic evaluation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Flame vine (Pyrostegia venusta) (FV), ice-cream-bean (Inga edulis) (IC), dog's knot (Heteropterys aphrodisiaca) (DK), and common bean (Phaseolus vulgaris L.) (BE) extracts were obtained by supercritical and subcritical fluid extraction (SFE) at 323 K and 35 MPa using pure carbon dioxide (CO2), carbon dioxide with ethanol (CO2 + EtOH) and carbon dioxide with water (CO2 + H2O). The extraction efficiency was evaluated by factoring in the solvent system and plant matrix influence in extraction yield (EY), antioxidant activity (AA), total phenolic content (TPC) and total flavonoid content (TFC). The manufacturing costs of crude extracts (COMEY) and phenolic-rich fractions (COMTPC) were also evaluated. The highest EY was achieved using CO2 + H2O, except for IC extracts. The BE extracts showed the highest TPC (338 mg GAE/g extract, dw), and the highest TFC was obtained for IC extracts using CO2 (260 mg CE/g extract, dw). AA achieved higher values for FV extracts using CO2 + EtOH (0.096 mL/mg). The lowest COMEY and COMTPC were obtained for FV and BE extracts using CO2 + H2O in a 0.5 m(3) extraction column. (C) 2014 Elsevier Ltd. All rights reserved.13196109Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPESP [2008/10986-2]CNPq [140290/2009-5, 301301/2010-7

Anacardium occidentale L. leaves extraction via SFE: Global yields, extraction kinetics, mathematical modeling and economic evaluation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The purpose of this work was to obtain extracts from Anacardium occidentale leaves using supercritical fluid extraction (SFE). The use of ethanol and isopropyl alcohol as co-solvents was evaluated. Mass transfer kinetics experiments were performed, and overall extraction curves were modeled. SFE process was compared with different low pressure solvent extraction processes in terms of global yield and the composition of the extract. The techniques used as low pressure solvent extraction processes were: Soxhlet extraction, agitated bed extraction, ultrasound assisted extraction using ethanol as the solvent and hydrodistillation. The extracts were analyzed by thin layer chromatography (TLC) using different eluents. Finally, the economic evaluation was conducted using the software SuperPro designer 6.0 (R) to simulate the process and to estimate the cost of manufacturing (COM) of SFE extracts. The results indicated the presence of essential oils, flavonoids and antioxidant compounds in all the extracts. The higher yield of extract was obtained with the ultrasound assisted extraction. However, the samples with more functional compounds were verified in the SFE extracts and the extracts showed low COM. The model that best described the overall extraction curves for the SFE process was the Sovova model, which showed minimum values for the sum of the squares of the residues. (c) 2013 Elsevier B.V. All rights reserved.78114123Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPERN [PPP003/2007]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPq [472023/2006-3]FAPERN [PPP003/2007]FAPESP [2008/10986-2

Near-critical carbon dioxide extraction of khoa (Satureja boliviana Benth Briq) using ethanol as a co-solvent: Experiment and modeling

In this work the volatile oil from khoa was extracted using pressurized CO(2) with and without ethanol as co-solvent. Kinetic experiments were performed at pressures of 6.5 and 7 MPa and temperatures of 294.15 K. The composition of the volatile oil was determined using gas chromatography. The volatile oil was formed predominantly by cymene, 1-8 cineole, isomenthone, pulegone, thymol and caryophyllene. Consequently, we present a mathematical modeling study of the extraction of essential oil from khoa. The overall extraction curves (OECs) obtained for khoa oil were modeled considering the mass transfer based on local equilibrium between solvent and a solid. The influence of pressure and co-solvent on the extraction kinetics was evaluated using a mathematical modeling. The model was solved numerically and validated with experimental data. A novel method for calculating the initial mass fraction of khoa-extract is proposed; data of the proposed model are in excellent agreement with the experimental data. Furthermore, the influence of fluid flow rate and particle size has been studied on the extraction efficiency. Finally, a methodology has been established to estimate extraction yield curves in large scale using the data obtained in small-scale experiments. (C) 2010 Elsevier B.V. All rights reserved.55392993

Upscaling microwave-assisted polymerizations

Driven by the success of microwave-assisted polymer chemistry as outlined in the other chapters of this series, the need for upscaling these processes has been identified. Within this chapter an overview is given of the general aspects of upscaling microwave-assisted polymerizations via both large batch reactors and continuous flow microwave reactors. Important challenges and limitations such as microwave penetration depth for large batch reactors and intrinsic temperature gradients in tubular flow reactors are discussed. An overview of the literature reports on upscaling of microwave-assisted polymerizations is also given