Analysis of macro nutrient content in biofouling waste organic fertilizer pearl oyster (Pinctada maxima L.)

Biofouling development is a major problem in bilvave aquaculture around the world. The purpose of this study was to obtain macro nutrient analysis data for organic fertilizer from pearl oyster (Pinctada maxima L) biofouling waste. Where is the manufacture of solid organic fertilizer products that have quality equivalent to other commercial organic fertilizers by utilizing pearl oyster (Pinctada maxima L.) biofouling waste so that high quality solid organic fertilizers are produced which are in accordance with the Quality Standards for solid organic fertilizers and the Indonesian National Standard. Organic fertilizer from pearl oyster biofouling waste is obtained by using pearl oyster biofouling waste which is taken from the results of cleaning microorganisms attached to the pearl oyster shell area. Another major concern regarding biofouling is the potential for food competition caused by the attachment of the filter-feeder. Besides, the waste of biofouling pearl oysters is extracted and soaked in fresh water for one week at a time. Afterward, the pearl oyster biofouling waste is dried in the sun to dry, odorless, blackish brown in color. Analysis of macro nutrient content using Atomic Absorption Spectrophotometer and UV-Vis Spectrophotometer. The results of the analysis of macro nutrient content were Water Content (5.76%), C (14.48%), Organic Matter (24%), N-total (0.92%), P-total (0, 25%), K-total (1.02%), C/N ratio (15.72).

Distribution of the Pearl Oyster Pinctada maxima off Eighty Mile Beach, Western Australia

The silver-lipped pearl oyster, Pinctada maxima, is the primary species used for the culture of pearls in the Indo-Pacific region. The Western Australian fishery relies on wild-caught animals, and as such, knowledge of the status and distribution of P. maxima underpins sustainable management of the fishery. Eighty Mile Beach, in tropical Western Australia, is the key harvest area for P. maxima, with oysters collected by divers to depths of ∼35 m, although there are anecdotal accounts of oysters beyond diving depths. Image-based, and acoustic methods were used to elucidate distribution patterns of P. maxima off Eighty Mile Beach, including data from 862 km2 of multibeam survey and 119 towed video transects spanning an area from the 20 to 100 m contour lines. We quantified habitat characters including depth, substrate, and benthic community composition associated with pearl oyster distribution. Multibeam sonar data was also coupled with towed video data to produce predictive statistical models of P. maxima habitat. We found P. maxima to depths of 76 m, although more than 90% of individuals occurred shallower than 40 m and less than 2% were found deeper than 50 m. Oysters occupied flat, sandy habitats with neighbouring benthic communities of filter feeders (>98% of observations). These results show P. maxima predominantly occurs in depths <40 m, with no evidence that extensive populations extend into deep water in the region.

Pearl Sac Gene Expression Profiles Associated With Pearl Attributes in the Silver-Lip Pearl Oyster, Pinctada maxima

Pearls are highly prized biomineralized gemstones produced by molluscs. The appearance and mineralogy of cultured pearls can vary markedly, greatly affecting their commercial value. To begin to understand the role of pearl sacs—organs that form in host oysters from explanted mantle tissues that surround and synthesize pearls—we undertook transcriptomic analyses to identify genes that are differentially expressed in sacs producing pearls with different surface and structural characteristics. Our results indicate that gene expression profiles correlate with different pearl defects, suggesting that gene regulation in the pearl sac contributes to pearl appearance and quality. For instance, pearl sacs that produced pearls with surface non-lustrous calcification significantly down-regulate genes associated with cilia and microtubule function compared to pearl sacs giving rise to lustrous pearls. These results suggest that gene expression profiling can advance our understanding of processes that control biomineralization, which may be of direct value to the pearl industry, particularly in relation to defects that result in low value pearls.

Demplot Budi Daya Lobster dan Kerang Mutiara secara Terintegrasi dalam Rangka Penguatan Kemitraan Masyarakat Lombok Utara

Integrated Community Partnership Program (PKM) activities of lobster and pearl shells with the aim of increasing marine aquaculture production through the application and development of integrated aquaculture technologies. In addition, this activity is expected to increase knowledge and skills in productive economic business activities. In addition, this activity is expected to increase knowledge and skills in productive economic business activities. The method of implementing PKM is the method of demonstration plot, where the target community groups play an active role at all stages of activities. Implementation of activities offered to support the realization of PKM activities with steps that have been mutually agreed upon include strengthening and socializing PKM activities, training, strengthening institutional management, demonstration plots of integrated system cultivation and coaching and mentoring. The results of PKM activities provide a positive value for the target community, with integrated aquaculture production of floating net cages (KJA) in the sea no longer relying on one commodity, but one KJA unit can produce two commodities namely lobster (Panulirus homarus) and pearl shells (Pinctada maxima). Thus the potential to provide additional income for the community from these two commodities. In addition, through this PKM activity, it is expected that the knowledge and skills of the target communities will increase in order to strengthen community partnerships.

Molecular identification of bacteria isolated from culture medium of the gold-lipped pearl oyster Pinctada maxima larvae

Wullur S, Napitupulu H, Wantania LL, Ginting EL, Mamangkey NGF, Smolak R, Ogello E. 2020. Molecular identification of bacteria isolated from culture medium of the gold-lipped pearl oyster Pinctada maxima larvae. Biodiversitas 21: 5291-5297. This study was conducted for the molecular identification of bacteria species isolated from culture medium of the gold-lipped pearl oyster, Pinctada maxima larvae. The pearl oysters were cultured using live-microalgae (Isochrysis sp) and fish waste diet (FWD) as food sources. Bacteria were isolated from the oyster larvae and identified based on the 16S rRNA gene sequence. The isolated bacteria were grown on agar plates and incubated at 37°C for 24 to 48 hours. Representative colonies of the bacteria were selected and cultured for molecular analysis. The 16S rRNA genes of the bacteria were amplified and the sequences were matched with the NCBI GenBank database. Seven different colonies were observed based on morphological characters. Similarity test by conducting the Basic Local Alignment Search Tool (BLAST) in the NCBI GenBank database, using the 16S rRNA gene sequences showed that the seven isolates colonies possess high similarity to five bacteria species i.e. Pseudomonas pachastrellae, Vibrio alginolyticus, Bacillus filamentosus, Bacillus cereus and Idiomarina fontislapidosi belonging to four different genera i.e. Bacillus, Staphylococcus, Vibrio, and Alteromonas.