The natural rubber latex extracted from the bark of Hevea brasiliensis plays various important roles in today's modern society. Following ultracentrifugation, the latex can be separated into 3 layers: C-serum, lutoids, and rubber particles. Previous studies have shown that a large number of proteins are present in these 3 layers. However, a complete proteome for this important plant is still unavailable. Protein sequences have been recently translated from the completed draft genome database of H. brasiliensis, leading to the creation of annotated protein databases of the following H. brasiliensis biosynthetic pathways: photosynthesis, latex allergens, rubberwood formation, latex biosynthesis, and disease resistance. This research was conducted to identify the proteins contained within the latex by way of de novo sequencing from mass spectral data obtained from the 3 layers of the latex. Peptides from these proteins were fragmented using collision-induced dissociation, higher-energy collisional dissociation, and electron-transfer dissociation activation methods. A large percentage of proteins from the biosynthetic pathways (63% to 100%) were successfully identified. In addition, a total of 1839 unique proteins were identified from the whole translated draft genome database (AnnHBM).
The effects of supplementing different dietary selenium (Se) sources on intestinal histomorphology, caecal bacterial proliferation, and caecum short-chain fatty acid in layer chickens were studied. A total of 120 of 54-week-old Lohman Brown Classic laying hens were subjected to four dietary treatments: control group with no Se supplementation (T1), 0.3 mg/kg of sodium selenite (T2), 0.3 mg/kg of selenium yeast (T3), and 0.3 mg/kg of bacterial Se (Stenotrophomonas maltophilia, ADS18) (T4). All treatments were also supplemented with 250 mg/kg of vitamin E. Results showed significantly (p < 0.05) higher villus height in different small intestine parts in hens fed with diets containing organic Se sources (T3 and T4), as compared to inorganic sources (T2) and control (T1). A greater crypt depth was observed for the T1 group, as compared to T3 and T4 groups. The total bacterial populations of Bifidobacteria spp. and Lactobacilli spp. were significantly increased (p < 0.05), and tEscherichia coli population was significantly decreased (p < 0.05) in T3 and T4 groups. No effect on the total caecal short-chain fatty acid (SCFAs) content was observed. However, there was a significant increase (21.5%) of the butyric acid content in T4 group. In conclusion, organic Se supplementation, particularly bacterial organic Se, enhances intestinal histomorphology, increases the beneficial caecal bacterial proliferation, and increases butyric acid content.