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91.
Paula Cristina Souza Barbosa Larissa Silveira Moreira Wiedemann Raquel da Silva Medeiros Paulo de Tarso Barbosa Sampaio Gil Vieira Valdir Florêncio da Veiga‐Junior 《化学与生物多样性》2013,10(7):1350-1360
Oils of various species of Copaifera are commonly found in pharmacies and on popular markets and are widely sold for their medicinal properties. However, the chemical variability between and within species and the lack of standardization of these oils have presented barriers to their wider commercialization. With the aim to recognize patterns for the chemical composition of copaiba oils, 22 oil samples of C. multijuga Hayne species were collected, esterified with CH2N2, and characterized by GC‐FID and GC/MS analyses. The chromatographic data were processed using hierarchical cluster analysis (HCA) and principal component analysis (PCA). In total, 35 components were identified in the oils, and the multivariate analyses (MVA) allowed the samples to be divided into three groups, with the sesquiterpenes β‐caryophyllene and caryophyllene oxide as the main components. These sesquiterpenes, which were detected in all the samples analyzed in different concentrations, were the most important constituents in the differentiation of the groups. There was a prevalence of sesquiterpenes in all the oils studied. In conclusion, GC‐FID and GC/MS analyses combined with MVA can be used to determine the chemical composition and to recognize chemical patterns of copaiba oils. 相似文献
92.
Joo Valdir Comasseto Leandro Helgueira Andrade lvaro Takeo Omori Leonardo Fernandes Assis Andr Luiz Meleiro Porto 《Journal of Molecular Catalysis .B, Enzymatic》2004,29(1-6):55-61
The enantioselective deracemization of a number of p-substituted aryl ethanols and the reduction of p-substituted acetophenones were carried out with whole fungal cells of Aspergillus terreus CCT 4083, A. terreus CCT 3320 and Rhizopus oryzae CCT 4964 giving the corresponding alcohols in enantiomeric excesses up to >99%. 相似文献