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15. Aromas from Quebec. V. Essential oils from the fruits and stems of Heracleum maximum Bartram and their unsaturated aliphaticacetates

Author

St-Gelais, Alexis, Collin, Guy, and Pichette, André

Abstract

Both the fruits and stems of Heracleum maximum Bartram, a common Apiaceae found throughout northern North America, have been traditionally consumed as spice and food by American First Nations and settlers. As both parts of the plant bear a distinctive scent, they have been submitted to volatile constituent extraction and their essential oils were studied by GC–FID and GC–MS. The fruits’ oil was found to be mostly constituted of aliphatic esters, with octyl acetate (65.6%) as main constituent, while the stems yielded a generally terpenic oil, dominated by limonene (45.2%). These results were in line with data for other Heracleum species, and constitute the first study of the volatile constituents of H. maximum. The observation of several octadecenyl acetates as trace compounds in the stems’ oil allowed for the comprehensive identification of these uncommon and closely related isomers.

Published
2016
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20. PHYSICAL AND MECHANICAL PROPERTIES OF PANEL BASED ON OUTER BARK PARTICLES OF WHITE BIRCH: MIXED PANELS WITH WOOD PARTICLES VERSUS WOOD FIBRES

Author

Pedieu, Roger, Riedl, Bernard, and Pichette, André

Subjects
Compuesto hidrofóbica de corteza, mechanical and physical properties, Hydrophobic bark composite, paneles mixtos, mixed panels, propiedades físicas y mecánicas
Abstract

The use of outer white birch bark in canoes is an example of its oldest use by the first nations in Canada. This use confirms the hydrophobic characteristics of this bark, which can be capitalized on by using it in the outer layers of three-layer mixed composite panels in order to protect them from water infiltration from their surface. These panels were made up of outer white birch bark particles in the surface layers with coarse wood particles or wood fibres in the core layer. A factorial experiment used in a complete block design permitted to carry a suitable statistical analysis of measured properties. The two main considered factors were respectively the bark percentages in the surface layers with three levels and the type of material used in the core with two levels. Four replicates were done for each panel. The panels with wood particles in the core layer gave physical and mechanical properties satisfying the indoor requirements for particleboards and those with wood fibres in the core layer passed the requirement of medium fibres density board. Panel with 45% bark particles in the surface and 55% wood particles in the core was selected as the best because of its good dimensional stability. El uso de la corteza externa de abeto blanco en la fabricación de canoas por las primeras naciones de Canadá es un ejemplo de su uso más antiguo. Esto confirma sus características hidrófugas, la cual puede ser explotada mediante su uso en la superficie del panel compuesto de 3 capas para protegerlo de filtraciones de humedad. Estos tableros fueron fabricados con partículas de corteza externa en las capas superficiales, y con partículas gruesas o fibras de madera en el corazón. Un experimento factorial en un diseño de bloque completo hizo posible realizar el diseño de experimento. Los dos grandes factores considerados, fueron el porcentaje de corteza en las capas superficiales con 3 niveles y el tipo de material usado en el corazón, con dos niveles respectivamente (partículas y fibras de madera). Cuatro réplicas fueron hechas para cada panel. Sólo los tableros con partículas gruesas de madera en el corazón pasaron todas las pruebas físicas satisfaciendo los requerimientos del interior de los tableros de partículas. Paneles con 45% de partículas de corteza en la superficie y 55% de partículas de madera en el corazón fueron seleccionados como los mejores, debido a su buena estabilidad dimensional.

Published
2008

33. Dihydrochalcone Derivatives from Populus balsamifera L. Buds for the Treatment of Psoriasis.

Author

Bélanger, Audrey, Grenier, Alexe, Simard, François, Gendreau, Isabelle, Pichette, André, Legault, Jean, and Pouliot, Roxane

Subjects
PSORIASIS, POPLARS, BUDS, NATIVE Americans, CELL growth
Abstract

Psoriasis is a skin disorder characterized by epidermal hyperplasia, hyperkeratosis, and inflammation. The treatments currently available on the market only improve patients' quality of life and are associated with undesirable side effects. Thus, research leading to the development of new, effective, and safer therapeutic agents is still relevant. Populus balsamifera L. buds were used traditionally by Native Americans to treat various skin pathologies such as eczema and psoriasis. In this study, the antipsoriatic activities of dihydrochalcone derivatives from Populus balsamifera L. buds, known as balsacones, were investigated. The experiments were performed in vitro using a psoriatic skin substitute model. Also, anti-inflammatory and antioxidant activities were investigated. The tested balsacones showed promising antipsoriatic properties by slowing down cell growth and by regulating the expression of involucrin, loricrin, and Ki67 better than methotrexate in psoriatic substitutes. All five tested compounds could be an effective topical treatment for psoriasis, with promising anti-inflammatory and antioxidant actions that may contribute to clinical improvement in patients with psoriasis. [ABSTRACT FROM AUTHOR]

Published
2020
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34. Antioxidant activity, inhibition of nitric oxide overproduction, and in vitro antiproliferative effect of maple sap and syrup from Acer saccharum.

Author

Legault J, Girard-Lalancette K, Grenon C, Dussault C, and Pichette A

Subjects
Animals, Antineoplastic Agents, Phytogenic therapeutic use, Antioxidants therapeutic use, Blueberry Plants, Cell Line, Cell Line, Tumor, Cell Proliferation drug effects, Citrus sinensis, Fibroblasts drug effects, Fibroblasts metabolism, Fragaria, Humans, Lipopolysaccharides, Macrophages drug effects, Macrophages metabolism, Mice, Phytotherapy, Plant Extracts therapeutic use, Plant Exudates, Reactive Oxygen Species metabolism, Acer, Antineoplastic Agents, Phytogenic pharmacology, Antioxidants pharmacology, Neoplasms drug therapy, Nitric Oxide biosynthesis, Plant Extracts pharmacology
Abstract

Antioxidant activity, inhibition of nitric oxide (NO) overproduction, and antiproliferative effect of ethyl acetate extracts of maple sap and syrup from 30 producers were evaluated in regard to the period of harvest in three different regions of Québec, Canada. Oxygen radical absorbance capacity (ORAC) values of maple sap and syrup extracts are, respectively, 12 +/- 6 and 15 +/- 5 micromol of Trolox equivalents (TE)/mg. The antioxidant activity was also confirmed by a cell-based assay. The period of harvest has no statistically significant incidence on the antioxidant activity of both extracts. The antioxidant activity of pure maple syrup was also determined using the ORAC assay. Results indicate that the ORAC value of pure maple syrup (8 +/- 2 micromol of TE/mL) is lower than the ORAC value of blueberry juice (24 +/- 1 micromol of TE/mL) but comparable to the ORAC values of strawberry (10.7 +/- 0.4 micromol of TE/mL) and orange (10.8 +/- 0.5 micromol of TE/mL) juices. Maple sap and syrup extracts showed to significantly inhibit lipopolysaccharide-induced NO overproduction in RAW264.7 murine macrophages. Maple syrup extract was significantly more active than maple sap extract, suggesting that the transformation of maple sap into syrup increases NO inhibition activity. The highest NO inhibition induced by the maple syrup extracts was observed at the end of the season. Moreover, darker maple syrup was found to be more active than clear maple syrup, suggesting that some colored oxidized compounds could be responsible in part for the activity. Finally, maple syrup extracts (50% inhibitory concentration = 42 +/- 6 microg/mL) and pure maple syrup possess a selective in vitro antiproliferative activity against cancer cells.

Published
2010
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