MALDI-TOF Mass Spectrometry for the Diagnosis of Citrus Canker Caused by Xanthomonas citri subsp. citri.

Citrus canker, caused by the bacterium Xanthomonas citri subsp. citri (Xcc), is a disease that causes serious problems to the global citrus industry. Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF) Mass Spectrometry (MS) has been used in human medicine to diagnose various diseases caused by both fungi and bacteria. In agriculture, this technique has potential for the diagnosis of diseases due to the low cost of large-scale analysis and quickness. This study showed that MALDI-TOF MS combined with chemometric analysis was effective for differentiating the macromolecule profile of orange leaves with canker lesions, healthy leaves, and leaves with phytotoxicity symptoms, proving that this technique may be used for the rapid diagnosis of citrus canker.

Chemical Profile and Use of the Peat as an Adsorbent for Extraction of Volatile Compounds from Leaves of Geranium (Pelargonium graveolens L' Herit).

Volatile organic compounds (VOCs) from leaves of geranium (Pelargonium graveolens L' Herit) were extracted by dynamic headspace using Porapak Q (HSD-P) as adsorbent and peat, a novel adsorbent in the extraction of plant volatiles, analyzed by gas chromatography-mass spectrometry (GC/MS) and gas chromatography-flame ionization (GC/FID), and the results were compared with those obtained by hydrodistillation (HD). The yield volatiles changed with the extraction method. HD was more efficient for extracting linalool (11.19%) and citronellyl formate (9.41%). Citronellol (28.06%), geraniol (38.26%) and 6,9-guaiadiene (9.55%) and geranyl tiglate (8.21%) were the major components identified by dynamic headspace using peat (HSD-T), while citronellol (16.88%), geraniol (13.63%), 6,9-guaiadiene (16.98%) and citronellyl formate (6.95%) were identified by dynamic headspace using Porapak Q (HSD-P). Furthermore, this work showed, for the first time, that in natura peat is useful to extract VOCs from leaves of geranium.

Isolation of Chavibetol and Methyleugenol from Essential Oil of Pimenta pseudocaryophyllus by High Performance Liquid Chromatography.

A high performance liquid chromatography (HPLC) method was developed for the simultaneous isolation, on a semi-preparative scale, of chavibetol and methyleugenol from the crude essential oil of P. pseudocaryophyllus leaves. The purity of the isolated compounds and their quantifications were developed using GC/FID. Chavibetol was isolated with high purity (98.7%) and mass recovery (94.6%). The mass recovery (86.4%) and purity (85.3%) of methyleugenol were lower than those of chavibetol. Both compounds were identified on the basis of spectral analysis. The results suggest that the method can provide chavibetol with high purity, mass recovery, and productivity from crude essential, which will be used in bioassays against stored insect pests.

Chemical Diversity in Lippia alba (Mill.) N. E. Brown Germplasm.

The aim of this study was to perform chemical characterization of Lippia alba accessions from the Active Germplasm Bank of the Federal University of Sergipe. A randomized block experimental design with two replications was applied. The analysis of the chemical composition of the essential oils was conducted using a gas chromatograph coupled to a mass spectrometer. The chemical composition of the essential oils allowed the accessions to be allocated to the following six groups: group 1: linalool, 1,8-cineole, and caryophyllene oxide; group 2: linalool, geranial, neral, 1,8-cineol, and caryophyllene oxide; group 3: limonene, carvone, and sabinene; group 4: carvone, limonene, g-muurolene, and myrcene; group 5: neral, geranial, and caryophyllene oxide; and group 6: geranial, neral, o-cymene, limonene, and caryophyllene oxide.

Influência do processamento da folha e tipo de secagem no teor e composição química do óleo essencial de manjericão cv. Maria Bonita / Influence of leaf processing and type of drying on the content and chemical composition of the essential oil of basil cv. Maria Bonita

O manjericão é uma planta medicinal aromática pertencente à família Lamiaceae, rica em óleos essenciais e com grande interesse industrial. Objetivou-se, no presente trabalho, estudar a influência do processamento da folha (inteira e pulverizada) submetida a dois tipos secagem (estufa de ventilação forçada a 38º C e sala com desumidificador), sobre o teor e composição química do óleo essencial. O delineamento utilizado foi o inteiramente casualizado (DIC), com 4 tratamentos e 6 repetições. O óleo essencial foi extraído por hidrodestilação das folhas e analisado por CG e CG/EM. O tipo de secagem e o processamento da folha do O. basilicum influenciaram no teor e composição química do óleo essencial. Maior porcentagem da área de pico do componente químico linalol foi obtida quando se realizou o processo de secagem das folhas. A secagem em estufa conservou o aroma e a coloração verde das folhas, preservando as características originais da cultivar.

Ocimum basilicum L. cv. Maria Bonita is a medicinal aromatic plant of the Lamiaceae family, it is rich in essential oils with high industrial interest. The present work aimed to study the influence of leaf processing (whole and ground leaf) in two drying types (oven-drying at 38º C and room temperature using moisture dryer) on the content and chemical composition of the essential oil. A completely randomized design was used with 4 treatments and 6 replicates. The essential oil obtained by hydrodestillation of the leaves was analyzed by GC and GC/MS. The results show that the drying type and the processing of the leaf influence the content and chemical composition of the essential oil. High amounts of linalol were obtained when the leaves underwent dry processing. The oven-dried conserved the aroma and the green color of the leaves, preserving the original characteristics of the cultivar.

Tipos e doses de adubação orgânica no crescimento, no rendimento e na composição química do óleo essencial de elixir paregórico / Sources and doses of organic fertilization in Ocimum selloi growth, essential oil yield and chemical composition

A prática da adubação orgânica, além de fornecer nutrientes para as plantas, proporciona a melhoria da estrutura física do solo, aumenta a retenção de água, diminui as perdas por erosão e favorece o controle biológico. O elixir paregórico (Ocimum selloi Benth.) é uma espécie medicinal nativa das regiões Sul e Sudeste do Brasil onde é utilizada popularmente como antidiarréico, antiespasmódico e antiinflamatório. Este trabalho teve como objetivo verificar o efeito de diferentes doses de dois adubos orgânicos no crescimento, no rendimento e na composição do óleo essencial de elixir paregórico. Os experimentos foram conduzidos em Lavras, MG, em estufa plástica com os seguintes tratamentos de adubação: ensaio A - esterco bovino: 1) sem adubação (controle); 2) solo + 3kg m-2 de esterco; 3) solo+ 6kg m-2 de esterco; 4) solo+ 9kg m-2 de esterco; 5) solo + 12kg m-2 de esterco; ensaio B - Esterco avícola: 1) sem adubação (controle); 2) solo + 1,5kg m-2 de esterco; 3) solo + 3kg m-2 de esterco; 4) solo + 4,5kg m-2 de esterco e 5) solo + 6kg m-2 de esterco. Foi verificada a influência das doses de adubação com esterco bovino e galinha sobre o crescimento da planta em altura e diâmetro do caule, acúmulo de biomassa seca, AF, AFE, RPF, teor de clorofilas, espessura do limbo foliar, rendimento e composição química do óleo essencial.

The organic fertilization provides nutrients for the plants, improves the soil physical structure, increases the water retention, reduces the erosion losses and favors the biological control. Ocimum selloi is a native medicinal plant of south and southeast of Brazil where is used popularly as antidiarrhetic, antispasmodic and anti-inflammatory. This research aimed to verify the effect of different doses of two organic fertilizers souces in O. selloi growth, essential oil yield and chemical composition. The experiments were carried out in Lavras, MG, with pots in polyethylene greenhouse with two manuring treatments: Test A - Cattle manure: 1) Soil without manuring (control); 2) Soil + 3kg m-2 cattle manure; 3) Soil + 6kg m-2 cattle manure; 4) Soil + 9kg m-2 cattle manure; 5) Soil + 12kg m-2 cattle manure; Test B - Chicken manure: 1) Soil without manuring (control); 2) Soil + 1.5kg m-2 chicken manure; 3) Soil + 3 kg m-2 chicken manure; 4) Soil + 4.5kg m-2 chicken manure and 5) Soil + 6kg m-2 chicken manure. The influence of cattle and chicken manuring doses was verified on plant height, stem diameter, dry biomass weight, TLA, SLA, LWR, chlorophylls content, leaf thickness, essential oil yield and composition.