The key breeding sites by pupal survey for dengue mosquito vectors, Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse), in Guba, Cebu City, Philippines.

We conducted this study to assess how well a pupal survey of dengue mosquito vectors, Aedes aegypti and Aedes albopictus, is able to target the most productive breeding sites. The study was carried out monthly during the rainy season (8 months) in 2008 in Cuba, Cebu City, Philippines. The hypotheses tested were: 1) most pupae of Ae. aegypti or Ae. albopictus were produced in a few types of breeding sites and 2) the most productive types of breeding sites for each species were the most abundant. Approximately 2,500 pupae were collected from 554 breeding sites in 279 houses. Thirty-eight point four percent of ten types of breeding sites were positive for Ae. aegypti, and 11.9% of nine types of sites were positive for Ae. albopictus. Plastic drums (40.2%), metal drums (29.6%), and plastic containers (10.5%) were the key sites for Ae. aegypti pupae, whereas bamboo stumps (28.5%), plastic drums (21.1%), and rubber tires (19.1%) were the key sites for Ae. albopictus. The most productive breeding sites for Ae. aegypti were common but not the most common for Ae. albopictus. These results are relevant for dengue vector control programs.

L-Lactic acid production from raw cassava starch in a circulating loop bioreactor with cells immobilized in loofa (Luffa cylindrica).

L-Lactic acid was produced from raw cassava starch, by simultaneous enzyme production, starch saccharification and fermentation in a circulating loop bioreactor with Aspergillus awamori and Lactococcus lactis spp. lactis immobilized in loofa sponge. A. awamori was immobilized directly in cylindrical loofa sponge while the L. lactis was immobilized in a loofa sponge alginate gel cube. In the loofa sponge alginate gel cube, the sponge serves as skeletal support for the gel with the cells. The alginate gel formed a hard outer layer covering the soft porous gel inside. By controlling the rate and frequency of broth circulation between the riser and downcomer columns, the riser could be maintained under aerobic condition while the downcomer was under anaerobic condition. Repeated fed-batch L-lactic acid production was performed for more than 400 h and the average lactic acid yield and productivity from raw cassava starch were 0.76 g lactic acid g(-1) starch and 1.6 g lactic acid l(-1) h(-1), respectively.