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In order to investigate the nutritive and ensiling characteristics of banana stems and leaves, the chemical compositions of banana stems and leaves were analyzed and the effects of additives on fermentation quality were measured. The research results showed: Banana stems and leaves had high fiber content (stem>58% DM, leaf >72% DM), nitrogen free extract content (>50% DM), and water soluble carbohydrate contents (WSC>5% DM), with certain nutritive value. Tannins of banana stem and leaf were 0.11% DM and 0.24% DM. There were lactic acid bacteria (>105cfu/g FM) in the banana stems and leaves; they might be well preserved with some treatments.

Four lactic acid bacteria (LAB) strains named HN78, HN87, HN91 and HN113 were separated fromStylosanthes guianensis SW. of Hainan province, which were identified bacterially using the classical classification and the sequences of 16S rDNA. The results showed that four strains wereEnterococcus hirae,Enterococcus faecalis,Lactococcus lactisandLactobacillus plantarum. The capability of lactic acid production of HN113 and HN91 were better than HN78 and HN87.

Cassava residues were taken as main raw material, Aspergillus oryzae and Aspergillus usamii were chosen as glucoamylase preparation, and response surface was used to optimize and analyze saccharification temperature, pH, rate of enzyme and total amount of Aspergillus (g/100g cassava residues) so order to find out the best operation conditon for cassava residues saccharification. It was found that the best operation condition for Aspergillus to saccharify cassava residues were as follows: saccharification temperature 70°C, pH 4, ratio of Aspergillus oryzae and Aspergillus usamii was 3:9, total amount of Aspergillus 10%, and it turned out to be a total reducing sugar content of 2.70g/L.

Pineapple peel as main material was fermented with Phaffia rhodozyma to produce astaxanthin. Using the Box-Behnken design, the effects of sugar content, initial pH and nitrogen content were studied with the yield of astaxanthin as response value, which was evaluated to optimize the fermentation conditions of astaxanthin production. The optimal fermentation conditions have been reached by the study: sugar content was 36.3 g/L, the initial pH was at 5.85 and nitrogen content was 8 g/L. By validation test, the astaxanthin yield under the optimal condition, which was basically corresponded to the model prediction, was 97.11 %.