Judul: Potensi Berat Basah Kaliandra (Calliandra calothyrsus) Berdasarkan Jumlah Percabangan.
Abstrak: Pendugaan potensi berat basah kaliandra melalui penerapan metode sampling memerlukan model alometrik, namun sayangnya model alometrik tersebut belum banyak dibuat. Penelitian ini bertujuan menduga potensi berat basah kaliandra berdasarkan jumlah percabangan dan penerapan pendugaanya. Penelitian dilakukan menggunakan metode sensus dan sampling. Metode sensus dilakukan untuk mendapatkan gambaran sebaran jumlah percabangan kaliandra. Berdasarkan hasil sensus tersebut, dilakukan pemilihan 35 pohon contoh secara purposive untuk mendapatkan rata-rata berat basah setiap jumlah percabangan kaliandra. Kaliandra contoh terpilih ditebang dan ditimbang berat basahnya. Hasil penelitian menunjukkan bahwa rata-rata berat basah kaliandra meningkat seiring dengan meningkatnya jumlah percabangan dan potensi berat basah kaliandra mencapai 27.62 ton/ha.
Keyword: jumlah percabangan, kaliandra, metode sampling, pelet kayu

Judul: Pengaruh Arang Sekam, Kompos dan Pupuk NPK terhadap Pertumbuhan Kaliandra Merah (Calliandra calothyrsus).
Abstrak: Kaliandra merah pada usia muda memiliki pertumbuhan yang lambat, sehingga perlu dilakukan pemupukan untuk meningkatkan pertumbuhan kaliandra merah di lapangan. Tujuan penelitian adalah mengetahui pengaruh arang sekam, kompos dan pupuk NPK terhadap pertumbuhan kaliandra di lapangan. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) faktorial 3x3x2 dengan 9 ulangan sehingga tanaman kaliandra merah yang digunakan sebanyak 162 bibit. Peubah yang diamati dalam penelitian ini adalah tinggi, diameter, berat basah daun dan cabang, berat kering daun dan cabang, panjang cabang, tinggi bebas cabang, jumlah cabang dan persen fase hidup. Hasil penelitian menunjukkan kombinasi perlakuan arang sekam, kompos dan pupuk NPK yang memberikan pengaruh nyata terhadap pertambahan diameter dan sangat nyata terhadap berat basah dan kering daun, serta berat basah dan kering cabang kaliandra merah. Perlakuan yang memberikan respon terbaik terhadap pertambahan diameter, berat basah dan kering daun, serta berat basah dan kering cabang kaliandra merah adalah A3B1C2, yaitu arang sekam 20%, tanpa kompos dan pupuk NPK 5 g.
Keyword: arang sekam, kaliandra merah, kompos, pertumbuhan, pupuk NPK

Judul: Extracellular Expression of thermostable Geobacillus stearothermophilus T1.2RQ Lipase for Biodiesel Production
Abstrak: The extracellular expression of enzymes in an excellent secretion host such as Bacillus subtilis is a useful strategy for making enzymes of industrial significance more affordable by lowering the cost of its downstream processing. Lipases are a category of hydrolases that catalyze the hydrolysis of triglycerides to glycerol and free fatty acids. Also, lipases catalyze the hydrolysis and transesterification of other esters as well as the synthesis of esters. They can perform very specific biotransformation reactions and are widely used in food, organic synthesis, detergents, cosmetic, and pharmaceutical industries. Geobacillus stearothermophilus T1.2RQ lipase is an industrially-desired thermostable lipolytic enzyme with an excellent hydrolytic and transesterification activity. This study aimed to express T1.2RQ lipase, in B. subtilis WB800 and ensure its secretion into the extracellular medium. Three signal peptides (AmyQ, Epr, LipA) and two promoters (Pgrac01 and Pgrac100) were used in the secretory-expression of T1.2RQ lipase, based on five constructed expression vectors constructed by restriction cloning and PCR mutagenesis. Sangers sequencing was used to verify constructs to ensure they are in the correct reading frame. Recombinants vectors, pHT43 (plasmid control), pHT43-T1.2RQ, pHT43- T1.2RQ_AmyQ, pHT43-T1.2RQ_Epr, and pHT43-T1.2RQ_LipA, were transformed by electroporation into Bacillus subtilis WB800. The electroporation was successful with the optimum condition of 2500V, 200 ohms, 25µF, and 5milliseconds. Recombinant B. subtilis pHT43 (negative control) and pHT43-T1.2RQlip + signal peptides were streaked on the lipidic agar, LA+TBN. All four recombinants, including the negative control (B. subtilis WB800-pHT43), produced clear zones on the TBN agar plate after overnight incubation (fig 2), indicating the presence of a lipolytic enzyme in all of the recombinant B. subtilis cells. pHT43-T1.2RQlip + signal peptides (AmyQ, Epr, and LipA) have clear zones with significantly higher diameters than B. subtilis WB800-pHT43 (negative control). This phenomenon suggests that the recombinant thermostable lipase T1.2RQ introduced into these cells was successfully expressed, thereby increasing the lipolytic capability of its host cells T1.2RQ lipase was expressed in 50ml terrific broth medium (TB) and the expression induced with 1mM IPTG. Lipase activity assay using p-nitrophenyl esters showed that all three signal peptides directed the secretion of T1.2RQ lipase into the extracellular medium. Signal peptide, LipA, resulted in the highest extracellular activity of 5.6 U/mL, which corresponds to a 6-fold increase over the parent B. subtilis WB800 strain. Meanwhile, signal peptides, AmyQ and Epr produced 4.2 U/mL and 3.4 U/mL activity respectively. SDS-Zymogram analysis confirmed that T1.2RQ lipase was correctly processed and secreted in its original size of 44 kDa. An attempt to further increase lipase expression level by promoter optimization showed that, contrary to expectation, promoter Pgrac100 exhibited similar expression levels as the original Pgrac01. Nevertheless, the demonstration of the successful secretion of T1.2RQ lipase in this work confirms the latter as a promising approach for the industrial production of the enzyme
Keyword: Bacillus subtilis, Expression, Extracellular, Heterologous, Lipase, Thermostable