Use of yeast crude extract for sequential injection determination of carbohydrates

Autor(es)

Silva‚ F.V. ; Souza‚ G.B. ; Nogueira‚ A.R.A.

• Tipo de documento: Artigo Científico
• Fonte: Analytical Letters; v. 34, n. 8, p. 1377-1388, 2001.

Resumo

A sequential injection procedure for enzymatic-potentiometric determination of non-structural carbohydrates content (sucrose, fructose and glucose) in forrage plants was developed. In the proposed methodology, a yeast crude extract (Saccharomyces cerevisae) solution was employed as source of invertase to promote the sucrose hydrolysis. Periodate reduction monitoring was used as quantitative parameter. The periodate remained from reduction reaction between IO4- ions and sugar reducing units was monitored using a periodate tubular selective electrode. Agreement results were obtained when the developed procedure was compared with the spectrophotometric method used for carbohydrate determination (anthrone). Detection limit of 0.13% (m v(-1)) sucrose, relative standard deviation <2.0% (n=10) and analytical frequency of 24 samples h(-1) could be observed when 280 mul of sample and yeast crude extract with activity around 5,000 I.U. were employed. The use of crude extract solution associated with sequential injection approach was easy to perform and presented reproductive results. (AU)

• Processo FAPESP: 98/10814-3 - Preparo de amostras agronômicas e determinações multielementares por espectrometria de emissão atômica em plasma induzido
• Beneficiário: Joaquim de Araújo Nóbrega
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 97/14499-2 - Determinacao de acucares redutores, amonia e acido latico em silagens com a utilizacao de analise por injecao sequencial.
• Beneficiário: Fernando Vitorino da Silva
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 00/00997-5 - Desenvolvimento e avaliação de procedimento para solubilização de amostras de interesse agronômico em sistema em fluxo a alta temperatura e alta pressão
• Beneficiário: Fernando Vitorino da Silva
• Modalidade de apoio: Bolsas no Brasil - Doutorado