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ABSTRAK
PENGGUNAAN RUMPUT LAUT Kappaphycus alvarezii
SEBAGAI BAHAN SUBTITUSI PADA PAKAN PENDEDERAN
UDANG PUTIH Litopenaeus vannamei POST – LARVAE 10
Oleh
Donny Kusuma Hardjani NIM : 30612003
(Program Studi Doktor Biologi)
Penurunan produksi sektor perikanan tangkap mendorong perkembangan sektor perikanan budidaya (akuakultur). Salah satu komoditas penting yang dibudidayakan adalah udang putih L i to p e n a e u s v a n n a m e i . Secara umum sistem budidaya di indonesia masih bersifat konvensional, kontrol budidaya yang rendah menyebabkan munculnya beberapa masalah salah satunya sindrom vibriosis. Penggunaan rumput laut di bidang akuakultur bertujuan sebagai antioksidan, antipatogen, dan imunostimulan. Kandungan karagenan pada rumput laut berpotensi sebagai imunostimulan yang mampu meningkatkan resistensi udang putih terhadap sindrom vibriosis. Kappaphycus alvarezii merupakan salah satu jenis rumput laut dengan kandungan karagenan sekitar 67,3%, namun kandungan protein dan lemaknya lebih rendah dibandingkan pakan konvensional. Rendahnya kandungan nutrisi K. alvarezii menyebabkan penggunaannya sebagai bahan subtitusi pada pakan memerlukan pengolahan sehingga didapatkan kandungan nutrisi yang lebih tinggi. Fermentasi dengan menggunakan ragi Saccharomyces cerevisiae dan penambahan Spirulina sp. merupakan 2 teknik pengolahan yang dilakukan pada penelitian ini. Penelitian ini bertujuan untuk mendapatkan komposisi rumput laut terbaik yang mampu meningkatkan resistensi udang terhadap sindrom vibriosis tanpa menurunkan pertumbuhan dan kualitas air, juga mengetahui pengaruh subtitusi terhadap aktivitas dan struktur mikroba yang bekerja pada sistem budidayanya.
Proses fermentasi menggunakan ragi Saccharomyces cerevisiae dilakukan dengan variasi inokulum 5% (v/v), 10% (v/v) dan 15% (v/v), setiap perlakuan diulang sebanyak 3 kali. Analisis nutrisi dilakukan dengan menggunakan metode proksimat, HPLC (asam amino), GC – MS (asam lemak). Berdasarkan laju pertumbuhan dan kandungan nutrisinya perlakuan penggunaan inokulum 10% (v/v) merupakan perlakuan terbaik dengan laju pertumbuhan sebesar 0,38 ± 0.05 h-1 dan peningkatan nutrisi yang mendukung resistensi L . v a n n a m e i terhadap sindrom vibriosis meliputi peningkatan karagenan terfermentasi 5,78%, asam amino ±20% dan asam lemak ±48%.
Pengujian dilakukan pada tahap pendederan dengan menggunakan L . v a n n a m e i post – larvae 10. Pengujian dilakukan sebanyak 3 kali dengan berbagai komposisi rumput laut K. alvarezii tanpa fermentasi, yang ditambahkan
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udang. Subtitusi berbagai komposisi rumput laut K. alvarezii tidak berpengaruh nyata terhadap parameter pertumbuhan (berat rata – rata, biomasa, FCR dan FER), kualitas fisik air (salinitas, suhu, pH dan DO) dan kualitas kimia air (ammonia, nitrit dan nitrat) jika dibandingkan dengan kontrol.
Pengujian aktivitas dilakukan menggunakan ecoplate pada seluruh perlakuan, sedangkan analisis struktur komunitas dilakukan hanya pada perlakuan terbaik menggunakan metode isolasi, purifikasi dan identifikasi (16sRNA). Penggunaan subtitusi berbagai macam komposisi K. alvarezii menurunkan aktivitas penggunaan substrat karbon oleh komunitas mikroba air dan saluran pencernaan udang dibandingkan dengan kontrol. Perubahan aktivitas komunitas mikroba disebabkan oleh kandungan pakan yang lebih kompleks, kandungan antimikroba pada pakan serta perubahan jumlah substrat yang terdapat pada air dan saluran pencernaan udang. Struktur komunitas pada perlakuan terbaik terdiri dari genus Alcaligenes, Bacillus, Microbacterium dan Myroides pada sampel air dan udang sedangkan Brachybacterium dan Pseudomonas hanya pada sampel udang. Bakteri genus Microbacterium, Myroides dan Brachybacterium hanya ditemukan pada perlakuan yang disubtitusi dengan rumput laut. Bakteri genus Microbacterium dan genus Myroides memiliki kemampuan menggunakan substrat kelompok polimer, karbohidrat, asam karboksilat, karbon fosfat, asam amino dan amina, sedangkan genus Brachybacterium secara spesifik mampu menggunakan substrat xylan. Bakteri dominan dari awal hingga akhir pemeliharaan pada sampel air adalah bakteri dari genus Bacillus, sedangkan pada saluran pencernaan adalah bakteri genus Pseudomonas dominan pada awal pemeliharaan dan bakteri genus Bacillus pada akhir pemeliharaan. Bakteri – bakteri dominan memiliki enzim katabolisme untuk mendegradasi substrat kelompok polimer, karbohidrat, asam karboksilat, karbon – fosfat, asam amino dan amina. Genus Bacillus, Alcaligenes dan Pseudomonas memiliki kemampuan untuk menghasilkan antimikroba berdasarkan kemampuannya menggunakan substrat asam itakonik. Peningkatan kesintasan pada pendederan udang putih kemungkinan tidak hanya dipengaruhi oleh faktor komposisi nutrisi pada rumput laut terfermentasi, namun dipengaruhi juga oleh aktivitas dan struktur komunitas mikroba perairan dan saluran pencernaan udang
Kata Kunci : Kappaphycus alvarezii, Saccharomyces cerevisiae, L i t o pe n a e u s
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ABSTRACT
SEAWEED Kappaphycus alvarezii AS FEED SUBSTITUTION IN
WHITE SHRIMP Litopenaeus vannamei
POST LARVAE 10 NURSERY
By
Donny Kusuma Hardjani NIM: 30612003
(Doctoral Program in Biology)
The decline in captured fisheries production encourages the development of aquaculture sector. One of the most important commodities in aquaculture is white shrimp Litopenaeus vannamei. Generally, aquaculture system in Indonesia is still conventionally cultivated and low control in the cultivation system causes several problems, with one of them being vibriosis syndrome. In aquaculture, seaweed is commonly used as feed for its antioxidants, antipathogen, and immunostimulant capabilities. Carrageenan in seaweed can potentially be used as an immunostimulant on white shrimp and increase vibriosis syndrome resistance. Kappaphycus alvarezii is a type of seaweed which contain about 67.3% of carrageenan. However, its protein and fat contents are lower than conventional feed. To be used as feed substitute, K. alvarezii needs to undergo pretreatments to increase its nutritional value. Fermentation using Saccharomyces cerevisiae yeast and the addition of Spirulina sp. are two processing techniques conducted in this study to increase the nutritional value of K. alvarezii. This study aims to obtain the best composition for K. alvarezii which can increase shrimp resistance to vibriosis syndrome without decreasing its growth and water quality. Furthermore, this study also aims to know the effect of feed substitution on microbial community activities and structures operated on the nursery system.
Fermentation process of K. alvarezii using S. cerevisiae was conducted with several inoculum variation; 5% (v/v), 10% (v/v), and 15% (v/v). Each treatment was repeated for 3 times. Nutritional analysis was performed using proximate methods, HPLC for amino acid contents, and GC - MS for fatty acid contents. The best yeast growth rate and nutritional contents was observed in K. alvarezii seaweed fermented using 10% (v/v) inoculum, having a growth rate of 0.38 ± 0.05 h-1, and nutritional contents which improve L. vannamei resistance to vibriosis syndrome include 5.78 % of fermented carrageenan, ± 20% amino acid , and ± 48% fatty acids.
The effect of several feed subtitution formulas in L. vannamei post - larvae 10 at the nursery stage was observed with two tests; a performance test (14 days) and a challenge test using V. harveyi bacteria (7 days). The tests was conducted for three times, using various composition of K. alvarezii without fermentation, K. alvarezii added with Spirulina sp., and fermented K. alvarezii. The nursery was kept as a batch system under controlled conditions. The final test shown that feed subtitution with 1.5% of fermented seaweed had 95.28% survival rate in the
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Microbial community activity testing was performed using ecoplate on all treatments, while isolation, purification and identification methods (16sRNA) for microbial community structure analysis was performed only on the best treatment observed. Various compositions of K. alvarezii in feed subtitutions decreased the activity of carbon substrate utilization by microbial communities in both water and shrimp gastrointestinal tracts compared to controls. Changes in microbial community activity are caused by the more complex feeding contents, antimicrobial contents in the diet and changes in the amount of substrate contained in water and gastrointestinal tracts. Community structure for the best treatment consists of several genera of Alcaligenes, Bacillus, Microbacterium and Myroides found on both water and shrimp samples, while Brachybacterium and Pseudomonas only found on shrimp samples. Microbacterium, Myroides and Brachybacterium genus are found only in seaweed substitution treatment. Bacteria from Microbacterium and Myroides genus have the ability to use polymer, carbohydrates, carboxylic acids, carbon phosphates, amino acids and amines group substrates, whereas Brachybacterium genus is specifically capable to utilize xylan substrates. Bacillus bacteria was found to be dominant on water samples during all nursery phases, whereas Pseudomonas bacteria was dominant at the beginning of nursery phase and Bacillus bacteria was dominant at the end of nursery phase. Bacillus and Pseudomonas have catabolism enzymes to degrade several substrate groups, such as polymer, carbohydrates, carboxylic acids, carbon-phosphates, amino acids and amines. Bacillus, Alcaligenes and Pseudomonas bacterias were able to produce antimicrobials substanced based on their ability to use itaconic acid substrate. Increased survival rate of white shrimp at nursery phase may not only be influenced by nutritional compositions in fermented seaweed, but also influenced by activity and microbial community structure on water and shrimp gastrointestinal tract.
Keywords: Kappaphycus alvarezii, Saccharomyces cerevisiae, Litopenaeus vannamei, survival rate, vibriosis, microbial activity, microbial community.
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ABSTRACT
SEAWEED Kappaphycus alvarezii AS FEED SUBSTITUTION IN
WHITE SHRIMP Litopenaeus vannamei
POST LARVAE 10 NURSERY
By
Donny Kusuma Hardjani NIM: 30612003
(Doctoral Program in Biology)
The decline in captured fisheries production encourages the development of aquaculture sector. One of the most important commodities in aquaculture is white shrimp Litopenaeus vannamei. Generally, aquaculture system in Indonesia is still conventionally cultivated and low control in the cultivation system causes several problems, with one of them being vibriosis syndrome. In aquaculture, seaweed is commonly used as feed for its antioxidants, antipathogen, and immunostimulant capabilities. Carrageenan in seaweed can potentially be used as an immunostimulant on white shrimp and increase vibriosis syndrome resistance. Kappaphycus alvarezii is a type of seaweed which contain about 67.3% of carrageenan. However, its protein and fat contents are lower than conventional feed. To be used as feed substitute, K. alvarezii needs to undergo pretreatments to increase its nutritional value. Fermentation using Saccharomyces cerevisiae yeast and the addition of Spirulina sp. are two processing techniques conducted in this study to increase the nutritional value of K. alvarezii. This study aims to obtain the best composition for K. alvarezii which can increase shrimp resistance to vibriosis syndrome without decreasing its growth and water quality. Furthermore, this study also aims to know the effect of feed substitution on microbial community activities and structures operated on the nursery system.
Fermentation process of K. alvarezii using S. cerevisiae was conducted with several inoculum variation; 5% (v/v), 10% (v/v), and 15% (v/v). Each treatment was repeated for 3 times. Nutritional analysis was performed using proximate methods, HPLC for amino acid contents, and GC - MS for fatty acid contents. The best yeast growth rate and nutritional contents was observed in K. alvarezii seaweed fermented using 10% (v/v) inoculum, having a growth rate of 0.38 ± 0.05 h-1, and nutritional contents which improve L. vannamei resistance to vibriosis syndrome include 5.78 % of fermented carrageenan, ± 20% amino acid , and ± 48% fatty acids.
The effect of several feed subtitution formulas in L. vannamei post - larvae 10 at the nursery stage was observed with two tests; a performance test (14 days) and a challenge test using V. harveyi bacteria (7 days). The tests was conducted for three times, using various composition of K. alvarezii without fermentation, K. alvarezii
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quality parameters (salinity, temperature, pH and DO) and water chemical quality parameters (ammonia, nitrite and nitrate) when compared to control.
Microbial community activity testing was performed using ecoplate on all treatments, while isolation, purification and identification methods (16sRNA) for microbial community structure analysis was performed only on the best treatment observed. Various compositions of K. alvarezii in feed subtitutions decreased the activity of carbon substrate utilization by microbial communities in both water and shrimp gastrointestinal tracts compared to controls. Changes in microbial community activity are caused by the more complex feeding contents, antimicrobial contents in the diet and changes in the amount of substrate contained in water and gastrointestinal tracts. Community structure for the best treatment consists of several genera of Alcaligenes, Bacillus, Microbacterium and Myroides found on both water and shrimp samples, while Brachybacterium and Pseudomonas only found on shrimp samples. Microbacterium, Myroides and Brachybacterium genus are found only in seaweed substitution treatment. Bacteria from Microbacterium and Myroides genus have the ability to use polymer, carbohydrates, carboxylic acids, carbon phosphates, amino acids and amines group substrates, whereas Brachybacterium genus is specifically capable to utilize xylan substrates. Bacillus bacteria was found to be dominant on water samples during all nursery phases, whereas Pseudomonas bacteria was dominant at the beginning of nursery phase and Bacillus bacteria was dominant at the end of nursery phase. Bacillus and Pseudomonas have catabolism enzymes to degrade several substrate groups, such as polymer, carbohydrates, carboxylic acids, carbon-phosphates, amino acids and amines. Bacillus, Alcaligenes and Pseudomonas bacterias were able to produce antimicrobials substanced based on their ability to use itaconic acid substrate. Increased survival rate of white shrimp at nursery phase may not only be influenced by nutritional compositions in fermented seaweed, but also influenced by activity and microbial community structure on water and shrimp gastrointestinal tract.
Keywords: Kappaphycus alvarezii, Saccharomyces cerevisiae, Litopenaeus vannamei, survival rate, vibriosis, microbial activity, microbial community.
