Influence of Kappaphycus Alvarezii and Gracilaria Salicornia Supplementation on in Vitro Fermentation Pattern, Total Gas and Methane Production of Mixed Substrates

This experiment was conducted to study the effect of supplementation of Kappaphycus alvarezii (KA) and Gracilaria salicornia (GS) in vitro fermentation pattern, total gas and methane production of mixed substrates. Basal substrate comprising of concentrates and wheat straw (50:50) was supplemented with either 0% (control), 1 (KA1), 2 (KA2), 4 (KA4), 6 (KA6), and 8 % (KA8) of Kappaphycus; and, 1 (GS1), 2 (GS2), 4 (GS4), 6 (GS6), and 8 (GS8 ) of Gracilaria, respectively. Asymptote, rate constant of gas production and t-half, concentration of total volatile fatty acids (TVFA), and in vitro dry matter digestibility (IVDMD) was not affected up to 2% level KA supplementation, beyond which asymptote, and rate constant of gas production, TVFA, and IVDMD decreased and t-half increased (P<0.001). Asymptote, rate constant of gas production, TVFA and IVDMD was not affected at 1% level of inclusion, beyond which a steady decline in these parameters was observed (P<0.001). Methane production (ml/g DM) was higher (P<0.001) in CON, followed by KA1 and KA2, and lower values were observed in by KA4, KA6 and KA8. Methane production (ml/kg DM) declined (P<0.001) steadily with increased level of GS in the substrates. From the results it was concluded that inclusion of Kappaphycus alvarezii and Gracilaria salicornia at 2 and 1%, respectively in the fermentation substrate can reduce in vitro methane production without any adverse impact on total gas production and in vitro dry matter digestibility.

Identifikasi Makroalga di Perairan Moudolung Kabupaten Sumba Timur

Makroalga merupakan sumberdaya hayati laut yang banyak ditemui di perairan Indonesia, salah satunya di Perairan Sumba Timur. Namun, sampai saat ini penyebaran makroalga di perairan Sumba Timur belum diidentifikasi spesiesnya. Langkah awal yang kami lakukan adalah memulai identifikasi makroalga di perairan Moudolung, alasanyanya penyebaran makroalga cukup melimpah. Tujuan dari penelitian ini adalah untuk mengidentifikasi setiap spesies makroalga yang tersebar di perairan Moudolung. Jenis penelitian yang digunakan adalah penelitian survei. Pengambilan sampel dilakukan pada tiga titik yaitu stasiun I (berpasir), stasiun II (lamun) dan stasiun III (berbatu), selanjutnya dilakukan identifikasi makroalga. Sampel makroalgae yang diperoleh diidentifikasi dengan menggunakan buku identifikasi makroalgae. Selain itu, juga dilakukan pengujian kualitas air (suhu, DO dan pH). Hasil penelitian menunjukkan bahwa kualitas air di perairan Moudolung cukup baik dengan rata-rata suhu adalah 29oC, DO sebesar 7.7-8.1mg/L dan pH sebesar 8.30-8.40. Sementara untuk hasil identifikasi makroalga terdapat 3 kelas utama makroalga yaitu alga cokelat 7 spesies (Hormophysa triquetra, Sargasssum muticum, Turbinaria ornata (Turner) J. Agardh, Sargasum plagyophyllum, Sargassum polycystum, Dictyota pinnatifida dan Padina australis), alga merah 5 spesies (Gracilaria corticata, Eucheuma spinosum, Gracilaria salicornia C. Agaradh, Achanthopora spicifera dan Achanthopora muscoides),dan alga hijau 3 spesies (Ulva flexuosa, Ulva reticulate dan Ulva compressa L.)

Performance of Low-Cost Agar from Gracilaria salicornia on Tissue Culture of Pleurotus HK-37

Currently, the demand of Pleurotus HK-37 (oyster mushroom) in Tanzania is growing rapidly due to the increasing of awareness on its nutrition, health, and economic benefits. Despite the increasing demand, the availability of strains of Pleurotus HK-37 species is still a challenge due to high cost of tissue culture technology. The high cost of importing agar seems to be among the factors for this failure. This study aimed at investigating the performance of low-cost agar from local Gracilaria salicornia on tissue culture of Pleurotus HK-37. Local extracted agars with different gel strengths ranging between 100, 200, 300, 400, and 500 g/cm2 were used to make PDA media. The average mycelia growth rate (mm/day) ranged between 9.87 ± 1.44 and 14.9 ± 0.85 mm/day. Low-cost agar shows quite similar performance as that of standard agar on active growth of Pleurotus HK-37 mycelia. All PDA plates appeared white and feathery and showed to grow in a circular mode (radial extension). Mycelia growth on standard agar PDA took 5 days while on extracted local agar PDA took 5 to 7 days to fully colonize the plate at 27 ± 2°C. The present study shows that the production cost can be reduced by ∼35–78% by using local agar.

KENEKARAGAMAN JENIS MAKROALGA YANG BERPOTENSI SEBAGAI BAHAN OBAT DI PERAIRAN PANTAI CIDATU KABUPATEN PANDEGLANG

Macroalgae have various types of polysaccharides such as alginate, gelatin, and bioactive compounds and contain potential pigments as drugs. Research on the diversity of macroalgae types that are potentially as medicinal substances in the waters of Cidatu Beach Pandeglang has done. Research is done by transek method. Sampling locations are differentiated into three stations. Each station is made of three transect with a distance between 5 m and each transect consisting of five plots 1x1 m with a distance between plots 5 m. The potentially medicinal macroalgae in the waters of Cidatu are 10 species which are 3 species of the Chlorophyceae class (Ulva intestinalis, Ulva reticulata and Chaetomorpha crassa), 4 species of the class Phaeophyceae (Padina australis, Turbinaria decurrens, Sargassum crassifolium, and Sargassum polycystum) and 3 species of the class Rhodophyceae (Gracilaria salicornia, Gracilaria coronopifolia and Gelidium sp). The index of diversity in Cidatu beach is 2.169 which is categorized diversity moderate type.