Publication Date
1985
Location
Kyoto Japan
Description
Leaf protein concentrate extracted from tree legume Leucaena leucocephala cultivar Cunningham (LLP) was stored under humid tropical conditions (24-28°C and 84-92% rh) in the form of wet cake during a 10 day period. Samples of LLP were taken every second day for chemical analyses and protein quality assays. The effect of storage on dried LLP was also assessed against two control proteins: peanut meal (PNM) and fish meal (FM), either free of aflatoxins or infected by the aflatoxigenic fungus Aspergi_llus flavus to the level 280 mcg aflatoxin B1 equivalent/kg. Storage of wet LLP under such conditions resulted in infestation by fungus A. Flavus with a gradual increase in aflatoxin content. While there was a gradual decrease in both DHP and oxidizing material levels, the incidence of liver lesions in ducks fed the LLP, indicating toxicity due to aflatoxins, substantially increased with storage. This did not cause deterioration of protein quality as measured by PER assay on the ducklings as had been expected from the increasing levels of aflatoxins; the longer the storage, the higher the nutritional value of LLP stored as wet cake. Contamination of LLP by A. flavus resulted in a progressive increase in dye-binding capacity and to a lesser extent in computed PER and amino acid indexes(EAAI and CS). There was a negative effect of aflatoxins on the nutritional value of dry protein concentrates infected with A. flavus and this effect was magnified by low quality proteins (LLP and PNM as compared to FM). The results indicate the importance of the problem of fungal contamination of leaf proteins in wet and/or dry form as well as other protein sources during their storage in humid tropical conditions. Storage of wet LLP positively affects animals and may be detected by those chemical methods used in projecting protein quality. This was not the case in dry proteins infected by culture of A. flavus. The positive effect of storing LLP in wet cake form prior to feeding warrants further study.
Citation
Ostrowski-Meissner, H T.; Komang, I; Supratman, W; Barchia, I; and Cacang, S, "Effect of Contamination by Aspergillus flavus on the Nutritive Value of Leaf Protein Concentrate of Leucaena leucocphala During Storage" (1985). IGC Proceedings (1985-2023). 32.
(URL: https://uknowledge.uky.edu/igc/1985/ses9/32)
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Effect of Contamination by Aspergillus flavus on the Nutritive Value of Leaf Protein Concentrate of Leucaena leucocphala During Storage
Kyoto Japan
Leaf protein concentrate extracted from tree legume Leucaena leucocephala cultivar Cunningham (LLP) was stored under humid tropical conditions (24-28°C and 84-92% rh) in the form of wet cake during a 10 day period. Samples of LLP were taken every second day for chemical analyses and protein quality assays. The effect of storage on dried LLP was also assessed against two control proteins: peanut meal (PNM) and fish meal (FM), either free of aflatoxins or infected by the aflatoxigenic fungus Aspergi_llus flavus to the level 280 mcg aflatoxin B1 equivalent/kg. Storage of wet LLP under such conditions resulted in infestation by fungus A. Flavus with a gradual increase in aflatoxin content. While there was a gradual decrease in both DHP and oxidizing material levels, the incidence of liver lesions in ducks fed the LLP, indicating toxicity due to aflatoxins, substantially increased with storage. This did not cause deterioration of protein quality as measured by PER assay on the ducklings as had been expected from the increasing levels of aflatoxins; the longer the storage, the higher the nutritional value of LLP stored as wet cake. Contamination of LLP by A. flavus resulted in a progressive increase in dye-binding capacity and to a lesser extent in computed PER and amino acid indexes(EAAI and CS). There was a negative effect of aflatoxins on the nutritional value of dry protein concentrates infected with A. flavus and this effect was magnified by low quality proteins (LLP and PNM as compared to FM). The results indicate the importance of the problem of fungal contamination of leaf proteins in wet and/or dry form as well as other protein sources during their storage in humid tropical conditions. Storage of wet LLP positively affects animals and may be detected by those chemical methods used in projecting protein quality. This was not the case in dry proteins infected by culture of A. flavus. The positive effect of storing LLP in wet cake form prior to feeding warrants further study.
