The microbial lipopeptides,which is an important kind of biosurfactants,possesses powerful surface activities and peculiar biological properties.

Antifungal activity of antimicrobial lipopeptide from Bacillus subtilis fmbJ to Penicillium notatum AS 3.

Human defensins are a family of cationic antimicrobial peptides with molecular weights of 4~5 kDa, containing conserved intramolecular 6 disulfide-linked cysteine residues.

Defensins contained in mussel and other marine mollusca are important antimicrobial peptides.

After the intestinal mucous membranes of chicken were treated by ultrasonic treatment and acid extraction,an antimicrobial peptide was isolated from the intestine of chicken by Sephadex G-50 gel filtration chromatography and centrifugal ultrafiltration.

Induction pattern of antimicrobial peptides genes in Drosophila;

After nitrogen depletion,significant fatty acid quantities were accumulated inside the fungal mycelia(50%~55%,weight oil ratio in dry biomass),resulting in a notable microbial oil production of 18.

The advantage, technology, effect factors in preparation of microbial oils and its utilization were introduced in paper.

The microbial oil richen in AA has been refined.

One option could be the exploitation of carbohydrate-based microorganism greasea,s it consists of similar fatty acids to that of plant oila,nd some organisms may also produce glycerides with high content of poly-unsatu-rated fatty acids(PUFAs).

This thesis summarized the significance and production technology of studying and developing microorganism grease.

The transesterification of microorganism grease with short-chain alcohols,in the presence of base-catalyst,by means of low frequency ultrasound(28 and 40kHz) in order to obtain biodiesel fuel was studied.