Publication Date
1985
Location
Kyoto Japan
Description
A comparison was made of in vitro and in vivo methods for the evaluation of protein quality in protein concentrates from leaves (LPC) of tree legume leucaena (Leucaena leucocephala) cultivars Cunningham and Peru grown in Indonesia and harvested during dry and wet seasons. Unfractionated protein concentrates were recovered by steam coagulation at either 85°C or 55°C (within 5 min of maceration and dejuicing). The leaves were evaluated using a number of in vitro and in vivo methods recommended for assessing food and feed grade proteins. In vitro methods used in this study tended to over-estimate the quality of leucaena protein as compared to the bioassays conducted on poultry or on the protozoon Tetrahymene pyriformis. Reactivity of lysine as measured by the dye-binding capacity method was well correlated with bioassay results. Assessment of the LPC from total amino acid content did not reflect the value of protein fed to chickens. Possible reasons for lack of correlation between the assays and an in vitro procedure for routine screening of nutritive value of leucaena protein are discussed. A dye-binding measurement of lysine content with simultaneous analyses of mimosine, DHP and oxidizable material, which indicate the presence of anti-nutritive compounds present in leucaena LPC (Tetrahymene pyriformis), have been tentatively adopted for routine assessment of leucaena protein preparations. Of bio-availability assays for lysine, sulfur-containing amino acids and tryptophan, the last was best correlated with the in vitro and in vivo assays, suggesting trytophan's nutritional importance in leucaena proteins.
Citation
Ostrowski-Meissner, H T.; Supratman, W; and Komang, i, "Assessing the Nutritive Value of Proteins Extracted from Leucaena leucocephala: A Comparison of In vivo and In vitro Assays" (1985). IGC Proceedings (1985-2023). 4.
(URL: https://uknowledge.uky.edu/igc/1985/ses9/4)
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Assessing the Nutritive Value of Proteins Extracted from Leucaena leucocephala: A Comparison of In vivo and In vitro Assays
Kyoto Japan
A comparison was made of in vitro and in vivo methods for the evaluation of protein quality in protein concentrates from leaves (LPC) of tree legume leucaena (Leucaena leucocephala) cultivars Cunningham and Peru grown in Indonesia and harvested during dry and wet seasons. Unfractionated protein concentrates were recovered by steam coagulation at either 85°C or 55°C (within 5 min of maceration and dejuicing). The leaves were evaluated using a number of in vitro and in vivo methods recommended for assessing food and feed grade proteins. In vitro methods used in this study tended to over-estimate the quality of leucaena protein as compared to the bioassays conducted on poultry or on the protozoon Tetrahymene pyriformis. Reactivity of lysine as measured by the dye-binding capacity method was well correlated with bioassay results. Assessment of the LPC from total amino acid content did not reflect the value of protein fed to chickens. Possible reasons for lack of correlation between the assays and an in vitro procedure for routine screening of nutritive value of leucaena protein are discussed. A dye-binding measurement of lysine content with simultaneous analyses of mimosine, DHP and oxidizable material, which indicate the presence of anti-nutritive compounds present in leucaena LPC (Tetrahymene pyriformis), have been tentatively adopted for routine assessment of leucaena protein preparations. Of bio-availability assays for lysine, sulfur-containing amino acids and tryptophan, the last was best correlated with the in vitro and in vivo assays, suggesting trytophan's nutritional importance in leucaena proteins.
