Tulang ikan kambing-kambing salah satu limbah padat yang masih menjadi hasil samping yang belum dimanfaatkan. Tulang ikan kambing-kambing merupakan salah satu limbah padat yang sangat berpotensi sebagai salah satu sumber kalsium. Penelitian ini bertujuan untuk memanfaatkan tulang ikan kambing-kambing  menjadi produk yang bernilai ekonomis dan sumber kalsium. Penelitian ini menggunakan metode hidrolisis protein untuk mengetahui karakteristik bahan baku tulang ikan kambing-kambing dan proksimat (kadar air, kadar lemak, kadar abu), kalsium dan nilai FTIR tepung tulang ikan kambing-kambing  yang dihasilkan. Penelitian ini menggunakan ekstraksi basa NaOH dengan perbedaan konsentrasi yaitu 1N, 1,5N dan 2N. Nilai rendemen yang didapatkan adalah 7,55%, 12,94% dan 10,96%. Nilai kadar air yang didapatkan adalah 3,79%,  4,15% dan 3,87%. Nilai kadar lemak adalah 0,12%, 0,11% dan 0,10%. Nilai kadar abu yang didapatkan adalah 90,05 %, 88,76% dan 87,52%. Nilai kalsium yang didapatkan adalah 31,83 %, 35,75% dan 32,33%. Pengujian FTIR menunjukkan pada tepung tulang ikan kambing-kambing terdapat kalsium.Kata kunci: ekstraksi; kalsium; ikan kambing-kambing (Abalistes stellaris) Starry triggerfish bone is one of the solid waste, which is a by-product that has not been utilized. It has great potential as a source of calcium. This research aims to utilize starry triggerfish bone to be a valuable product and source of calcium. This research used the protein hydrolysis method to determine the characteristic of raw material and proximate of starry triggerfish bone (water, fat and ash content), calcium and FTIR values of starry triggerfish bone meal. This research uses NaOH base extraction with different concentrations of 1N, 5N and 2N. The yield value obtained were 7,55%, 12,4% and 10,96%. The values of water content obtained were 3,7%, 4,15% and 3,87%. The value of fat content were 0,12%, 0,11% and 0,10%. Ash content values obtained were 90,05%, 88,76% and 87,52%. Calcium values obtained were 31,83%, 35,75% and 32,33%. FTIR testing showed that the bone meal of starry triggerfish contained calcium.Keywords: extraction; calcium; starry triggerfish (Abalistes stellaris)

AbstrakPenelitian ini bertujuan untuk mengetahui pengaruh Penambahan nanokalsium cangkang tiram (Crassostrea gigas) pada pakan dengan dosis berbeda terhadap pertumbuhan udang galah (macrobrachium rosenbergii). Rancangan percobaan yang digunakan adalah Rancangan Acak Lengkap (RAL) dengan 4 perlakuan dan 3 ulangan, pada perlakuan A (pakan komersial tanpa penambahan CaO). Perlakuan B (pakan komersial dengan tambahan 1% CaO), perlakuan C (pakan komersial dengan penambahan 2% CaO), perlakuan D (pakan komersial dengan penambahan 3% CaO). Kemudian selama penelitian 2 bulan pada akuarium dilengkapi juga sistem resirkulasi. Hasil penelitian menunjukkan dengan penambahan nanokalsium sebanyak 2% berpengaruh nyata terhadap kelangsungan hidup Udang yaitu A 95.0%, B 95.0%, C 100% dan D 92.5%, dan pada frekuensi molting udang galah memiliki tingkat tertinggi yaitu A 0,64 kali/ekor, lalu diikuti oleh perlakuan B 0,63 kali/ekor, kemudian diikuti oleh perlakuan D yaitu 0,53 kali/ekor, dan yang terendah diikuti oleh perlakuan A 0,51 kali/ekor.Kata kunci: nanokalsium; kelangsungan hidup; pertumbuhan; udang galahAbstractThis study aims to determine the effect of the addition of oyster shell nano-calcium (Crassostrea gigas) at different doses on the growth of giant shrimp (Macrobrachium rosenbergii). The experimental design used was Completely Randomized Design (CRD) with four treatments and two replications, in treatment A (commercial food without CaO addition). Treatment B (commercial feed with additional CaO 1%), treatment C (commercial feed with the addition of 2% CaO), treatment D (commercial feed with an addition of 3%). Then for two months of research there was an aquarium equipped with a recirculation system. The results showed that with nano-calcium approvals of 2% real participation in the survival of giant prawns, namely A 95.0%, B 95.0%, C 100% and D 92,5 %. and the moulting frequency of giant shrimp has the highest level of C 0.64 times/individual, then followed by treatment B 0.63 times/individual, then followed by treatment D 0.53 times/individual, and the lowest was followed by treatment A 0.51 times/individual.Keywords: nano-calcium; survival rate; growth; giant prawn

Oyster is one of bivalve groups widely consumed by human, thus, it results in producing huge waste shells affecting the environment. One way to increase the value of oyster shells is to process them into chitosan. This study aims to isolate chitin then synthesize it into chitosan and convert chitosan into nano-sized chitosan and analyze the characteristics. The steps to produce chitosan from waste shells included demineralization using HCl 1 N and deproteinization using NaOH 3%. The next step was to convert chitin into chitosan through a deacetylation process using NaOH 50%. After chitosan was formed, it was continued to convert chitosan into nano chitosan particles using ion gelation method with the addition of surfactant (tween 80) and crosslinker (TPP 0.1% and 0.5%). The results showed that yield of transformation chitin into chitosan was 61.1%. Meanwhile, the yield calculated from initial weight of raw material was 18.33% with deacetylation degree value equal to 89.14%. Based on morphological analysis using SEM, the size of chitosan particles was not distributed homogeneously that was in the range of 892 nm-1.54 μm, while the nano chitosan particle size obtained was uniformly formed in the range of 679 nm-910 nm.

Abstract. Mud crab shell is one of the most fisheries waste can be utilized as calcium source because it contains lots of calcium carbonat. Utilizing of crab shells flour in fed is important applied as calcium supplements to freshwater prawn. The purpose of this research is to knows the effects of calcium addition from mud crab shells on fed to increase the growth rate, survival rate and moulting frequency freshwater prawn. The research has been done during 70 days in fisheris Laboratory, Abulyatama University. Result of the research shows that two percents calcium addition on fed give higher growth rate value, survival rate value and moulting frequency value than other treatments and were not added calcium on fed. The average of freshwater prawn growth rate are treatment A (0% CaO)= 1.20 g, B (1% CaO) = 1.41 g, C (2% CaO) = 1.92 g, D (3% CaO) = 1.77 g. The average of freshwater prawn survival rate result shown by treatment A = 75 %, B = 91,1 %, C = 91,1 %, and D = 89 %. The moulting frequency value results shown by treatment A = 1,06 ; B = 1,22; C = 1,57 and D = 1,34. Keywords : Calcium, Freshwater Prawn, Macrobranchium rosenbergii, Moulting Abstrak. Cangkang kepiting bakau merupakan salah satu limbah perikanan yang dapat dimanfaatkan sebagai sumber kalsium karena cangkang kepiting mengandung kalsium karbonat tinggi. Pemanfaatan tepung cangkang kepiting pada pakan adalah sebagai suplemen. Tujuan dari penelitian ini untuk mengetahui pengaruh penambahan mineral kalsium dari cangkang kepiting bakau pada pakan untuk meningkatkan laju pertumbuhan, kelangsungan hidup dan frekuensi molting udang galah. Penelitian ini dilakukan selama 70 hari di laboratorium perikanan, Universitas Abulyatama. Hasil dari penelitian menunjukkan bahwa penambahan 2 % kalsium pada pakan memberikan hasil tertinggi untuk laju pertumbuhan, kelangsungan hiidup dan frekuensi molting udang galah dibanding perlakuan lain. Nilai rata-rata pertumbuhan udang galah tiap perlakuan adalah sebagai A (0% CaO) = 1,20 gr, B (1% CaO) = 1.41 gr, C (2% CaO) = 1.92 gr dan D (3% CaO) = 1,77 gr. Sedangkang nilai rata-rata kelangsungan hidup udang galah adalah A = 75 %, B = 91,1 %, C =91,1 % dan D = 89 %. Nilai ata-rata frekuensi molting udang galah selama pemeliharaan pada tiap perlakuan adalah A = 1,06 kali/ekor, B = 1,22 kali/ekor, C = 1,57 kali/ekor dan D = 1,34 kali/ekor. Kata kunci: Kalsium, Macrobranchium rosenbergii, Moulting, Udang Galah

Sodium silicate is a commonly used activator in geopolymer that is produced commercially. In this study, rice husk ash (RHA) from agricultural waste was used to synthesize sodium silicate as an activator for geopolymer cement. This white ash was applied for producing sodium silicate with different molarities (8, 10, and 12) and then used to synthesize fly ash-based geopolymer cement. Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) were applied to investigate the micro-characteristics of the geopolymerization products. Bulk density, water absorption, compressive strength, flexural strength, and fracture toughness were carried out to measure and evaluate the geopolymers with sodium silicate. The combination of 10 M NaOH with sodium silicate increased the compressive strength by 16.21% and the flexural strength and fracture toughness by 81.6%. However, sodium silicate combined with 12 M NaOH decreased compressive strengths by 13.23% and flexural strength and fracture toughness by 61.94%. The lowest water absorption value of 12.3% was obtained in a geopolymer paste using sodium silicate combined with 10 M NaOH, and the largest was 13.3% for sodium silicate combined with 8 M NaOH. The microstructure analysis showed the hydrated calcium alumina silicate gel (C–A–S–H) and the SEM image also revealed a compact geopolymer matrix. Thus, it can be concluded that sodium silicate from rice husk ash can be utilized as an activator or reactive material to produce geopolymer cement with a good geopolymer network.