No abstract

Microorganisms have a high potential as biofuel sources. Co-culture of microalgae and yeasts can result in high lipid production as a modification treatment. The goal of this study was to see how the co-culture of the Glagah consortium (diversity of associated microalgae and bacteria from Glagah Lagoon, Yogyakarta) and Lipomyces starkeyi affected the production of biomass, lipids, proteins, and carbohydrates. The culture was performed under airtight conditions on a shaker at 127 rpm, with a light intensity of 27.75 mol/m2/s and a temperature of 30°C. The culture was subjected to a dark: light (6:18) treatment. Biomass was measured by dry weight, lipids by the Bligh and Dyer method, proteins by the Bradford method and carbohydrates by the phenol-sulfuric acid method. On day 3, L. starkey culture produced the most biomass, yielding 2.21 g/L with a productivity of 0.49 g/L/day. On day 4, the highest lipids produced from co-culture treatment yielded 1.03 g/g with a productivity of 0.21 g/L/day. The highest protein yield was obtained from L. starkeyi culture treatment on day 4, yielding 0.60 g/g with a productivity of 0.12 g/L/day. On day 6, co-culture produced the total carbohydrates, yielding 4.78 g/g with a productivity of 0.68 g/L/day. The co-culture treatment produced the highest lipids and carbohydrates production (1.03 g/g and 4.78 g/g) and productivity (0.21 g/L/day and 0.68 g/L/day), while L. starkeyi culture produced the highest total biomass and protein production (2.21 g/L and 0.6 g/g)  and productivity (0.49 g\L\day and 0.12 g/L/day). In microalgae culture, CO2 generally given directly through the aeration process. In this study, the source of CO2 was yeast, whereas yeast also obtained O2 from microalgae in the consortium for their metabolic process. This mutualism symbiosis will help in providing benefits in reducing the costs for the cultivation process, especially in optimizing the production of biomass an lipids.

Indonesia is a maritime country with high diversity of marine biota, which one is from Phylum Echinoderms. Echinoderms are known as biota of marine which is are living on corals, sandy, and on the intertidal zone and deep ocean. The intertidal characteristics of Sundak Beach has a suitable structure to echinodems life because there are many corals, but there is many species has not been identified before. The purpose of this research is to know the diversity of echinoderms phylum on the intertidal zone. Sampling was carried out on August, 24th 2019 with purposive random sampling method along the coastal-line in intertidal zone. The result of this research are identified and classified on the each class. Based on the results, the are found species from Echinodea, Holothuroidea, and Ophiuroidea. Species from Echinoidea are Tripneustes gratilla, Echinometra mathaei, Heterocentrotus trigonarius, Diadema antillarum., and Echinothrix calamaris. Holothuroidea namely Holothuria atra. Ophiuroidea namely Ophiotrix fragilis, Ophiocoma scolopendrina, and Ophiocoma erinaceus. The conclusion from this study is the discovery of five species from class Echinoidea, one species from class Holothuroidea and three species from class Ophiuroidea.

Echinoderm is one of the phylum which has high diversity and abundance in Indonesia, especially in Gunung Kidul, Yogyakarta. Sadranan and Slili beach are side by side beach located in Gunung Kidul. This beach is dominated by coral and rocky coral with macroalgae that provide the habitat of Echinoderms. This research is conducted to study the abundance and distribution pattern of Echinoderms in the intertidal zone between Sadranan and Slili beach. Sampling was carried out on Friday, 4 October 2019 at 05.00 p.m. in the intertidal zone using quadrat plot methods. The beach area is 2240 m2 which is divided into 21 plots with 1 x 1 m size. Data analysis was performed by measuring Margalef index (D), Pielou index (e), and Shannon-Wiener index (H’) then analyzing the distribution pattern and habitat parameters. The result shows that the Echinoderms which has the highest abundance is Echinometra mathei with 19 individual founds. The distribution pattern of Echinometra mathei, Stomopneustes variolaris, Heterocentrotus trigonarius, Ophiocoma erinaceus, Macrophiotrix longipeda, Ophiomastix annulosa, and Echinus sp. is clumped. The distribution pattern of Tripneustes gratilla, Diadema antillarum, Echinotrix calamaris, and Ophiocoma scolopendrina is uniform