F. A. Pimentel

Bio: F. A. Pimentel is an academic researcher from Empresa Brasileira de Pesquisa Agropecuária. The author has contributed to research in topics: Essential oil & Steam distillation. The author has an hindex of 9, co-authored 19 publications receiving 323 citations. Previous affiliations of F. A. Pimentel include Universidade Federal de Lavras.

Influência da luz e da temperatura sobre a oxidação do óleo essencial de capim-limão (Cymbopogon citratus (D.C.) Stapf)

Abstract: The identification of the chemical compounds of the essential oil was performed with a gas chromatograph coupled to a mass spectrometer. The oil was left in the presence and absence of light and submitted to different temperatures to evaluate its stability. The yields of the major compounds were evaluated every fifteen days. Citral and myrcene, the major compounds of the essential oil, were degraded over time in both the presence and absence of light, but temperature only influenced the degradation of myrcene.

A convenient method for the determination of moisture in aromatic plants

Abstract: A method is proposed for the determination of the moisture content of aromatic plants. This method is based on the co-distillation of the starting material in a modified Clevenger apparatus with four organic solvents (toluene, cyclohexane, dichloromethane and carbon tetrachloride). The results were compared with those obtained by oven drying at 105 oC and steam distillation of the essential oil. The efficiencies of the methods were shown to be equivalent. The solvent distillation method was more practical, especially with respect to operating time (2 h).

Emprego do carvão ativado para remoção de cobre em cachaça

Abstract: Copper content is of great concern among sugarcane-spirit producers. It is released from copper-made distillers, during the distillation process. Activated carbon has been used to remove copper. However, depending on the amount of carbon and the duration of reaction, it can also remove higher alcohols and esters, which are important in the final product. A sugarcane spirit with 9 mg L-1 of copper was shaken with 2 to 26 g L-1 of activated carbon, during 10 to 1440 minutes. Then, copper and organic compounds were measured. At least 12 g L-1 of carbon and 60 min shaking time were necessary to decrease copper bellow 5 mg L-1. However, other components of the product were also affected.

Potencial fungitóxico do óleo essencial de Piper hispidinervum (pimenta longa) sobre os fungos fitopatogênicos Bipolaris sorokiniana, Fusarium oxysporum e Colletotrichum gloeosporioides

Abstract: The objective of this study was to evaluate the in vitro antifungal activity of the essential oil of the leaves of Piper hispidinervum against Bipolaris sorokiniana, Fusarium oxysporum and Colletotrichum gloeosporioides. For the biological tests, using the bioanalitic test in vitro the concentrations of 100, 200, 500, 1000, 1500 and 2000 µg.mL-1 the essential oil. This were incorporated into PDA (potato dextrose agar) medium in order to evaluate fungal mycelial growth or inhibition. The statistic design used was completely randomized, with four replicates. In the concentration of 200 µg.mL-1, observed inhibited complete the phytopathogens Bipolaris sorokiniana while the Fusarium oxysporum and Colletotrichum gloeosporioides this is occurred in the concentration of 1000 µg.mL-1.

Sarisan from leaves of Piper affinis hispidinervum C. DC (long pepper)

Abstract: The essential oil obtained from the leaves of Piper affinis hispidinervum C. DC was analysed by GC– MS. Sixteen substances were identified, corresponding to 98.9% of the oil. The major component (74.3%) was sarisan (1-allyl-2-methoxy-4,5-methylenedioxybenzene), identified by NMR spectroscopy. Safrole (18.4%) was also found in the oil. Copyright © 2001 John Wiley & Sons, Ltd.

Solvent Supercritical Fluid Technologies to Extract Bioactive Compounds from Natural Sources: A Review.

Abstract: Supercritical fluid technologies offer a propitious method for drug discovery from natural sources. Such methods require relatively short processing times, produce extracts with little or no organic co-solvent, and are able to extract bioactive molecules whilst minimising degradation. Supercritical fluid extraction (SFE) provides a range of benefits, as well as offering routes to overcome some of the limitations that exist with the conventional methods of extraction. Unfortunately, SFE-based methods are not without their own shortcomings; two major ones being: (1) the high establishment cost; and (2) the selective solvent nature of CO2, i.e., that CO2 only dissolves small non-polar molecules, although this can be viewed as a positive outcome provided bioactive molecules are extracted during solvent-based SFE. This review provides an update of SFE methods for natural products and outlines the main operating parameters for extract recovery. Selected processing considerations are presented regarding supercritical fluids and the development and application of ultrasonic-assisted SFE methods, as well as providing some of the key aspects of SFE scalability.

Supercritical fluid extraction of plant flavors and fragrances.

Abstract: Supercritical fluid extraction (SFE) of plant material with solvents like CO2, propane, butane, or ethylene is a topic of growing interest. SFE allows the processing of plant material at low temperatures, hence limiting thermal degradation, and avoids the use of toxic solvents. Although today SFE is mainly used for decaffeination of coffee and tea as well as production of hop extracts on a large scale, there is also a growing interest in this extraction method for other industrial applications operating at different scales. In this review we update the literature data on SFE technology, with particular reference to flavors and fragrance, by comparing traditional extraction techniques of some industrial medicinal and aromatic crops with SFE. Moreover, we describe the biological activity of SFE extracts by describing their insecticidal, acaricidal, antimycotic, antimicrobial, cytotoxic and antioxidant properties. Finally, we discuss the process modelling, mass-transfer mechanisms, kinetics parameters and thermodynamic by giving an overview of SFE potential in the flavors and fragrances arena.

Influência dos fatores abióticos na composição química dos óleos essenciais.

Abstract: Os oleos essenciais constituem um dos mais importantes grupos de materias primas para as industrias de alimentos, farmaceutica, perfumaria e afins. Sao constituidos por uma mistura complexa de diversas classes de substâncias, dentre elas os fenilpropanoides, mono e sesquiterpenos, pertencentes ao metabolismo secundarios das plantas. O metabolismo secundario por sua vez pode ser influenciado, dentre outros, por fatores geneticos, climaticos (temperatura, intensidade de luz, efeito sazonal, etc.) e edaficos. Observa-se que, grande parte das especies popularmente utilizadas, encontra-se proxima ao estado silvestre, mantendo forte interacao com o ambiente. Informacoes sobre o efeito de condicoes ambientais no metabolismo secundario de plantas provem principalmente de esforcos da pesquisa para maximizar a producao de constituintes ativos de especies medicinais e aromaticas. Como aplicacao pratica, avancos no sentido de compreender a influencia dos fatores ambientais na regulacao de biossintese de metabolitos secundarios, podem contribuir para um aumento na producao de compostos de interesse nestas especies. Neste artigo sera abordada a acao de alguns fatores abioticos no rendimento e composicao de oleos essenciais, com base nos dados da literatura, sem a pretensao de esgotar este extenso tema.