Use of spectrophotometric method lignin acetyl bromide for determining lignin content in forage plants

• Grant number: 09/00074-9
• Support Opportunities: Scholarships abroad - Research
• Start date: May 30, 2009
• End date: September 29, 2009
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Romualdo Shigueo Fukushima
• Grantee: Romualdo Shigueo Fukushima
• Host Investigator: Monty S. Kerley
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: University of Missouri, Columbia (UM), United States

Abstract

Lignin quantification by the spectrophotometric method using as standard the lignin isolated from the plant has been gathering the attention of researchers in Brazil and worldwide. It is well known that there is not an ideal method for lignin quantification in vegetable products. Accuracy of analytical procedures employed nowadays are questionable, particularly the acid detergent lignin (ADL), which is the most widely used method. Because the present procedure is a spectrophotometric method (UV light at 280 nm), it is necessary the use of a standard (in the present case, it is the lignin extracted from the plant using acidic dioxane) with which is made the standard curve. Before, from each vegetable sample it was extracted lignin and the respective standard curve built. However, in several occasions the number of samples being studied is high, which turns the utilization of this method problematic. Thus, more studies aiming at speeding up the procedure, particularly the question of standard curve, were absolutely necessary, if it is desired that the present technique be accepted in other laboratories of food analysis. One possible solution could be the search for a 'universal standard', that is a lignin extracted from one plant type and use this lignin to quantify lignin content in any plant, no matter if it is a grass species, a legume, a bamboo or a wood sample. This research project is being finalized here at University of Missouri, Animal Sciences Division.In this premise, it was of fundamental importance that all lignins behaved the same at 280 nm, no matter which plant species being studied. To verify this hypothesis, lignin was extracted from 14 plants (grass, legume, bamboo and wood samples) and purified three commercial (Aldrich) lignins. As expected, all curves had similar intercepts and slopes. Once proved the hypothesis that any lignin can be used as standard and for this method be better accepted by other researchers, other projects should be conducted in order to show positive results. Other analytical methods should be used for comparative purposes and lignin results from all methods correlated with 'in vitro' dry matter digestibility. That is the objective of this proposal. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

FUKUSHIMA, ROMUALDO S.; KERLEY, MONTY S.; RAMOS, MARCELO H.; PORTER, JAMES H.; KALLENBACH, ROBERT L.. Comparison of acetyl bromide lignin with acid detergent lignin and Klason lignin and correlation with in vitro forage degradability. ANIMAL FEED SCIENCE AND TECHNOLOGY, v. 201, p. 25-37, MAR 2015. (09/00074-9)