Probiotic has been widely used in functional food because of numerous advantages for health. MRS broth is commonly used as standard medium in studying lactobacilli. However, in some communities - like muslim and vegetarian society, components in MRS broth/medium become an issue. Beef extract and peptone – animal derived substances as nitrogen sources in the MRS medium should be avoided for the vegetarian. Meanwhile, for the muslim society, all components must be halal-certified including those animal derived ingredients. Therefore, several alternative sources for beef extract and peptone substitution were studied. Combination of alternative nitrogen sources was applied. In order to increase the effect of the alternative nitrogen sources, alternative carbon sources were also included. This is the first report about effects of L. brevis media components on cells growth to expression level of surface layer protein (Slp). Whey, lactose, sucrose, and galactose showed high contribution to L. brevis growth. However, the tested concentration of those substances were not sufficient to obtain equal bacterial growth and Slp expression than that of MRS broth. In addition, yeast extract appeared necessary to maintain cell wall and Slp expression.

One of the most promising ways to produce high hydrogen yield is through dark fermentation by using dark fermentative bacteria due to the capability of these microbial agents to convert various organic compounds, particularly sugar, into hydrogen gas. In this study, three Gram-positive hydrogen-producing bacteria with a different character of colony on agar, namely as RP 009, RP 010, and RP 011, had been successfully isolated from Mount Pancar hot spring, West Java. All these isolates were able to produce hydrogen gas in all cheese whey concentration, consisting of cheese whey 30%, 60%, and 100%. RP 011 was the most favorable hydrogen producers in this study due to its high hydrogen productivity (4,400.625 ml biogas/L medium) as well as its ability to adapt and consecutively produce hydrogen even in the very high concentration of the organic compound. The best cheese whey concentration for hydrogen production in this study was 60%, considering the efficiency and effectiveness of the organic compound conversion into hydrogen gas. Ultimately, this study presented the potential of high hydrogen productivity of indigenous hot spring bacteria isolated from Mount Pancar hot spring in which had major potential for environmentally friendly bioenergy and biomass refineries.

Morphology and molecular characterization of microalgae isolated from Wakatobi Marine National Park was conducted. An understanding of the characteristics of morphology, molecular, as well as metabolites profile of the microalgae species is potentially useful for its future application. The primary aim of this study was to isolate, identify and characterize the microalgae strain isolated from Wakatobi Marine National Park labeled as LIPI13-WKT066 with the emphasis on the evaluation of amino acid content as a basis for its health application. Morphological observation under the microscope and molecular identification suggested that the microalgae strain of LIPI13-WKT066 belong to the strain under species of Chlorella volutis. Metabolite characterization of the microalgae strain showed that the content of protein (11.9%), lipid (12.4%) and carbohydrate (4.7%) was in the regular range. Further analysis of its amino acid content revealed the potency of the microalgae strain to be used as antihypertensive agent.

Three strains of fast-growing microalgae were investigated in this study for their potential of lipid production and its possible use in health application. Lipid content, lipid productivity, and fatty acids profile of the 3 microalgae strains were also analyzed. The strain of LBB13-2-AL045 and LBB13-2-AL048 possessed highest lipid content (49.08 ± 0.25%) and lipid productivity (40.27 ± 1.91 mg.L-1 .day-1), respectively, among the other tested strains. The fatty acids profile from the 3 strains exhibited its possible use in health application. The two strains of LBB13-2-AL046 and LBB13-2-AL048 possessed high valuable fatty acids of polyunsaturated fatty acids (PUFA) omega-3 and omega-6, whereas LBB13-2-AL045 possessed balance ratio of saturated fatty acid (SFA) : monounsaturated fatty acid (MUFA) : PUFA (1 : 1.3 : 1) as is recommended by American Heart Association (AHA) (1 : 1.4 : 0.8). The high content of omega-3 and omega-6 fatty acids indicated that the algal lipids of two strains (LBB13-2-AL046 and LBB13-2-AL048) were potential to be applied in cardiovascular health. The balance ratio of SFA : MUFA: PUFA as is recommended by AHA indicated that the algal oil of LBB13-2-AL045 strain was recommended in order to generate the best LDL/HDL ratio.

AbstrakC-fikosianin adalah senyawa pigmen-aksesori fotosintetik berwarna biru yang terkandung dalam sianobakteria. Jaaginema sp. BTM-11 merupakan sianobakteria laut yang memiliki potensi sebagai penghasil pigmen C-fikosianin karena kandungannya yang tinggi. Nilai ekonomis pigmen C-fikosianin sangat ditentukan oleh rasio kemurnian yang dimilikinya. Penelitian ini bertujuan untuk meningkatkan kemurnian pigmen C-fikosianin dari ekstrak sianobakteria laut Jaaginema sp. BTM-11 dengan menggunakan kitosan dan arang aktif. Variabel independen pada penelitian ini adalah konsentrasi kitosan (0,075-3,750 g/L) dan konsentrasi arang aktif (2,5-10 g/L). Toksisitas C-fikosianin diuji dengan menggunakan metode Brine Shrimp Lethality Test (BSLT) untuk mendapatkan nilai Konsentrasi Letal-50 (LC50). Penggunaan kitosan konsentrasi 0,3 g/L yang dilanjutkan dengan penggunaan arang aktif konsentrasi 5,0 g/L berhasil meningkatkan rasio kemurnian pigmen C-fikosianin sebesar 57,5 dan 167,5%, secara berturut-turut. Kapasitas pengikatan kitosan dan kapasitas penjerapan arang aktif secara signifikan berhasil meningkatkan kemurnian C-fikosianin dari awalnya 0,900±0,067 menjadi 2,408±0,171. Peningkatan rasio kemurnian C-fikosianin juga diikuti dengan peningkatan toksisitas fraksi C-fikosianin sianobakteria laut Jaaginema sp. BTM-11. Nilai LC50 ekstrak Jaaginema sp. BTM-11 sebelum pemurnian yang sebesar 15,75 ppm meningkat menjadi 12,06 ppm setelah dimurnikan dengan kitosan dan arang aktif. Enhancement of Purity and Toxicity of C-Phycocyanin Pigment Extracted from Marine Cyanobacteria Jaaginema sp. BTM-11 Using Chitosan and Activated CarbonAbstractC-phycocyanin is a blue colored accessory photosynthetic pigment found in cyanobacteria. Jaaginema sp. BTM-11 is marine cyanobacteria which is potential to be used as C-phycocyanin producer due to its high contents. The economical value of the blue pigment, C-phycocyanin, is determined by its purity. This research aimed to enhancing the purity of C-phycocyanin extracted from marine cyanobacteria of Jaaginema sp. BTM-11 using chitosan and activated carbon. The independent variables of this research were chitosan concentration (0.075-3.750 g/L) and activated carbon concentration (2.50-10.0 g/L). The toxicity test of C-phycocyanin was carried out using Brine Shrimp Lethality Test (BSLT) method to obtain the Lethal Concentration-50 (LC50) value. The application of 0.3 g/L chitosan continued by of 5.0 g/L activated carbon was successfully increased the purity of C-phycocyanin by 57.5 and 167.5%, respectively. Binding capacity of chitosan and adsorption capacity of activated carbon succeed to significantly increase the purity ratio of C-phycocyanin from 0.900±0.067 to 2.408±0.171. The enhancement of purity ratio of C-phycocyanin fraction extracted from Jaaginema sp. BTM-11 was also followed by the enhancement of its toxicity. LC50 of C-phycocyanin extract before purification (15.75 ppm) was lower compared to the C-phycocyanin fraction (12.06 ppm) after being treated with chitosan and activated carbon.

The need of nitrogen (N) for the growth of Spirulina platensis and the production of protein and phycocyanin pigment is influenced by the type of source and the concentration of N contained in the growing media. Spirulina platensis can assimilate various N sources, including nitrate (NO3-) and urea. Urea is a cheap N source and easy to be obtained. Urea can also have a role as potential N source to support the growth and the metabolites production of cyanobacteria S. platensis. Partial substitution of N source (NO3‑) to urea in Zarrouk medium for S. platensis cultivation has not been conducted before. This study was aiming at determining the optimum ratio of NaNO3 : CO(NH2)2 and the optimum N concentration in the Zarrouk medium for protein and phycocyanin production by S. platensis. Response Surface Method (RSM)-one factor experimental design was employed in this study for determining the optimum N concentration at specific N concentration range and optimum ratio of N source that had been previously determined. The results demonstrated that the optimum ratio of NaNO3 : CO(NH2)2 for protein and phycocyanin production was 1:1. The optimum N concentration for protein and phycocyanin pigment production in S. platensis cultivation were 5.13 mmol L-1 and 4.94 mmol L-1 with the increament in about 51.95% and 25.16%, respectively, compared to the standar Zarrouk medium.Kebutuhan unsur nitrogen (N) untuk pertumbuhan Spirulina platensis serta produksi protein dan pigmen fikosianin dipengaruhi oleh jenis sumber dan konsentrasi N yang terkandung dalam media tumbuh. Spirulina platensis dapat mengasimilasi berbagai sumber N, termasuk nitrat (NO3-) dan urea. Urea merupakan sumber N yang murah dan mudah diperoleh. Urea juga dapat berperan sebagai sumber N potensial untuk mendukung pertumbuhan dan produksi metabolit pada sianobakteria S. platensis. Substitusi sebagian sumber N (NaNO3) oleh urea dalam media Zarrouk untuk kultivasi S. platensis belum banyak dilakukan sebelumnya. Penelitian ini bertujuan untuk menentukan nisbah NaNO3 : CO(NH2)2 dan konsentrasi N optimum yang diperlukan dalam media Zarrouk untuk produksi protein dan fikosianin oleh S. platensis. Desain eksperimen RSM-one factor digunakan dalam penentuan konsentrasi N optimum pada rentang konsentrasi N dan nisbah sumber N optimum yang telah ditentukan sebelumnya. Hasil penelitian menunjukkan bahwa nisbah NaNO3 : CO(NH2)2 optimum untuk meningkatkan kandungan protein dan pigmen fikosianin S. platensis adalah 1:1. Konsentrasi N optimum untuk produksi protein dan pigmen fikosianin pada kultivasi S. platensis ialah 5,13 mmol L-1 dan 4,94 mmol L-1 dengan peningkatan sebesar 51,95% dan 25,16%, secara berturut-turut, bila dibandingkan dengan saat dikultivasi menggunakan media Zarrouk standar.

This study sought to evaluate the influence of hot water extract addition on cell growth, biomass production and lipid productivity during cultivation of microalgae Choricystis sp. LBB13-AL045 under different light intensity. The cellular growth of microalgae in terms of growth rate and produced biomass increased significantly with the addition of hot water extract into the microalgal culture under both low- and high-light intensity (3000 and 30000 lux, respectively), demonstrating that hot water extract of microalgal biomass positively interferes with the metabolism of microalgae and the production of biomass. Thus, microalgal lipid productivity was eventually increased almost three times when hot water extract (7,5 mg/mL) was employed in the microalgal cultivation with high light intensity. Hot water extract was prepared by the autoclaving varied concentration of dried microalgal biomass (2,5-7,5 mg/mL) in water. The cultivation of Choricystis sp. LBB13-AL045 showed the highest net increase of biomass production (975,05 mg) at hot water extract concentration of 7,5 mg/mL and light intensity of 30000 lux. The current investigation demonstrates that hot water extract of Choricystis’s dried biomass accelerate its growth and induce its lipid productivity for its application in biodiesel production.

This study sought to evaluate the influence of natural stone presence that was collected from Aceh Province, on the growth and the production of biomass, protein, total sugar and lipid of the microalgae Chlorella vulgaris LIPI12-AL042. Aceh’s natural stone used in this study were nephrite jade (NJ) and black jade (BJ) which were known to possess different minerals composition. The cellular growth of microalgae in terms of biomass yield and its productivity increased significantly (13,38%) under the presence of BJ stone compared to the control. Different results of reduced biomass yield and its productivity were demonstrated by the microalgae culture under the influence of NJ stone’s presence compared to the control. In terms of total sugar, both stones exhibited superior results over the control. The protein content and its yield of the Chlorella vulgaris LIPI12-AL042 cultivated under the influence of the stones demonstrated less quantity over the control.