Chitin a natural polymer extracted commercially from the shells of crustaceans such as prawns, crabs, krill, insects and shrimps. Chitosan is prepared from chitin by partially deacylating its acetamido groups with a strong alkaline solution. Chitin and chitosan have a wide variety of applications such as wastewater treatment which decreases the Chemical Oxygen Demand [COD] and used in preventin...

Every year, over 8 million tons of crustacean shells are discarded. However, there exists an opportunity for valorizing the chitin and calcium carbonate part composition shells. Our study revealed reduces self-aggregation effects. It was shown that crustacean-based nanofibers alone or added to cellulose offer unprecedented reductions in viscosity even after drying produce foams impossible cellu...

Chitosan is a derivative of chitin, a compound usually isolated from the shells of some crustaceans such as crab, lobster and shrimp. It has biocompatible, biodegradable, and antimicrobial properties. To use these properties of chitosan in biomedical fields, chitosan films (1%, 2%, 3% and 4%) were prepared by using l% lactic acid as solvent. The effects of chitosan films on tensile strength, el...

It has been shown (1, 2) that in human milk there are N-acetyl-n-glucosamine-containing oligosaccharides which promote the growth of Lactobacillus bifidus var. Penn. In the search for substances with lower molecular weight which would still show a growth-promoting effect in the microbiological test, activity was found in mildly hydrolyzed chitin of crab and lobster shells,’ in P-methyl N-acetyl...

Production of extracellular endochitinase could be increased 5-fold in the mycoparasite fungus Trichoderma harzianum by using the cellulase promoter cbh1 of Trichoderma reesei, whereas the total endochitinase activity increased 10-fold. The cbh1 promoter was not expressed on glucose and sucrose in T. harzianum and was induced by sophorose and on cellulase-inducing medium. The endogenous endochi...

Chitinous material was extracted from mycelia of Aspergillus niger and Mucor rouxii grown in yeast peptone dextrose broth for 15 and 21 days, respectively. The extracted material was characterized for purity, degree of acetylation, and crystallinity and tested for antibacterial and eliciting properties. The maximum glucosamine level determined in the mycelium of A. niger was 11.10% dw and in th...

A study on morphometric relationships between the hermit crab Isocheles sawayai and its shell in a population from Paraná-Santa Catarina States coast was carried out. Hermit crabs from the by-catch of shrimp fishing (4-15m depth) were collected. Cephalothoracic shield length (CL) and width (CW) from hermit crabs and total length (SL), aperture length (AL) and weight (SW) from shells were taken....

AT THE REQUEST of Dr. Ernst S. Reese of the Universi ty of Hawaii the wri ter has studied seven specimens of a polyclad turbellarian found in the shells of Trocbus sand taicbensis occupied by the hermit crab Calcines latens in Kaneohe Bay, Oahu, Hawaiian Islands. Accord ing to Dr. Reese ( in litt. ) the worm wraps itself around the abdomen of the crab and usually occurs deep in the spira l cavi...

Coenobita compressus (H. Milne Edwards) walk forward on six legs using an alternating tripod gait similar to that of insects. The first walking leg provides the driving force for locomotion aided secondarily by the second walking leg, while the chelipeds act largely as supports. The left appendages are longer and heavier than the right, and they extend further laterally from the midline during ...