APLICATION OF CHITOSAN FOR WATER QUALITY AND MACROBENTHIC FAUNA REHABILITATION IN VANNAMEI SHRIMPS (LITOPENAEUS VANNAMEI) PONDS, NORTH COAST OF SEMARANG, CENTRAL JAVA - INDONESIA

Abstract

Chitosan was widely known as natural food preservative such as noodle, meat ball, soy-tofu, wide variety of
fresh vegetables, fruits, meat and fish products, etc. Chitosan is a non-toxic substances, has no side effect as
human food and was made from the shell of shrimps (Penaeidae), or swimming crabs (Portunus pelagicus).
Chitosan is primarily a polysacharids, with β-1,4-2 amino-2-deoxy- β- D-glucopyranose. The biopolymer
has various noble functional characters such as anti-moth, anti-bacterial, coagulating agent for suspension,
or heavy metals. This substance had been examined in the Lab of Natural Product, Diponegoro University
and give a significant effect as bacteriostatic and bactericides for pathogenic bacteria such as Salmonela.sp;
Pseudomonas, E.coli, B.subtilis, S.aureus, P.aeruginosa. In the study, liquid chitosan (200 ppm) was used as
anti- harmful/ pathogenic bacteria in the brackish water pond so that can eliminate and control the bacterial
or virus outbreak which so far is the main problems in the fish and shrimp culture activities. The use of
chitosan in the brackish water ponds was carried out at a semi-traditional ponds at Mangkang Kulon north
Semarang coastal area. The experiment had significantly decrease the suspended solid or increase water
transparency, and the organic content ( by 5 %) of the bottom susbtrate. Increase the abundance of
important macro-benthic organism such as Polychaeta (7-fold) as important natural feed for the cultured fish
and shrimp as well as increase the diversity index of total macro-benthic organism. Decrease the growth of
disease vector benthic organism such as Cherithidae (Gastropods) by 24.5% . With the application of
chitosan had significantly prevent the outbreak of fish and shrimp disease and increase up to 80 % the
survival rate of Vanamae, as well as tiger shrimp Penaeus monodon, and polkadot grouper (Cromileptes,sp)
in another field application.