Closed Culture System Research Articles

Transcriptomic analysis of gonads in Malabar red snapper (Lutjanus malabaricus) reveals genes associated with gonad development

Malabar red snapper (Lutjanus malabaricus) is an important and high-value aquaculture species in Singapore that is attracting substantial interest and new industry investment. The consistent production of good quality eggs is an important step for establishing a selective breeding program for the species in Singapore. To achieve improved spawning outcomes, reproductive studies are needed to address the challenges in Malabar red snapper seed production, such as limited spawning success in closed culture systems. However, despite its rising profile as an aquaculture candidate and the need to improve broodstock husbandry, currently there are scarce genomic resources for the species, particularly related to genes involved in sex determination and differentiation. Herein, we report the first gonadal transcriptomes of adult L. malabaricus generated using RNA-Seq of testes (n = 6) and ovaries (n = 6). A total of 14,421 significant differentially expressed genes (DEGs) were found by comparing the gene expression profiles of ovaries and testes, including 6499 upregulated female-biased and 7922 downregulated male-biased DEGs. These DEGs included genes known to be involved in reproductive processes such as male-biased dmrt1, spat4, odf3b and sox9, and female-biased cyp19a1, zp4, sox3, bmp15 and esr1. The expression level of 16 selected DEGs were validated by RT-qPCR. This study lays the basis for further research in genes involved in sex determination and differentiation, sex control and breeding in Malabar red snapper.

The Effect of Different Concentration of Liquid Organic Fertilizer on the Growth of Sea Grape (Caulerpa lentillifera)

Sea grapes (Caulerpa lentillifera) have potential economic value and need to be conserved in their natural environment. The growth and distribution of C. lentillifera depend on physical (such as substrate) and chemical (nutrient) factors of the marine environment. The purpose of this study is to analyze the effect of different concentrations of liquid organic fertilizers on the growth of C. lentillifera in a closed culture system. This research was done from April to June 2022. The culture of C. lentillifera was done under a closed culture system using a fiber cage (50 x 50 x 60 cm) inside a (plastic) greenhouse. The experimental design used a complete randomized design of 5 treatments with three replications each. Variables observed during this study were length, weight, and sea grape ramuli quantity. The data was analyzed by using one-way ANOVA. The results show that adding liquid organic fertilizer with different concentrations has an impact on the sea grape weight (F value 3.764 > F tab 3.48) and an increase in the quantity of sea grape ramuli (F value 3.608 > F tab 3.48). The optimum concentration of liquid organic fertilizer for the growth of sea grapes was 20 ml.L−1. The culture of C. lentillifera can be done in a closed system and give good results in its growth. Further study still needs to be done by applying different treatments such as salinity and temperature in order to get exactly good conditions for C. lentillifera to grow in culture conditions and give a good quality that can be consumed and a good economic value.

Alterations in the gut microbiome of whiteleg shrimp (Penaeus vannamei) postlarvae following exposure to an AHPND-causing strain of Vibrio parahaemolyticus

Acute hepatopancreatic necrosis disease (AHPND), attributed to the production of PirA/PirB toxins by certain Vibrio sp. strains, poses a significant threat to global shrimp aquaculture, causing substantial mortality and economic losses. To enhance our understanding of this disease within a closed culture system on the northern coast of Peru, we conducted a comparative analysis of the gut microbiomes between healthy and diseased postlarvae. Diseased postlarvae were obtained through exposure to an AHPND-causing strain of Vibrio parahaemolyticus. Five healthy and five diseased postlarvae were randomly sampled from experimental rearing tanks, and their medial guts were extracted. High-throughput sequencing targeting the V4 region of the 16S rRNA gene was employed for amplicon library construction, and assessments of alpha and beta diversities and taxonomic composition were conducted. Our results revealed reduced diversity and distinct compositional profiles in the gut microbiomes of diseased postlarvae. The order Rhodobacteriales was dominant in the gut microbiomes of healthy postlarvae. In contrast, the order Vibrionales (including an unassigned genus within Vibrionales, Vibrio, and Pseudoalteromonas) exhibited the highest abundance in diseased postlarvae. In conclusion, exposure to an AHPND-causing strain of V. parahaemolyticus induces significant dysbiosis in the gut microbiome of whiteleg shrimp postlarvae.

Kelps on demand: Closed-system protocols for culturing large bull kelp sporophytes for research and restoration.

Culturing kelps for commercial, conservation, and scientific purposes is becoming increasingly widespread. However, kelp aquaculture methods are typically designed for ocean-based farms, and these methods may not be applicable for smaller scale cultivation efforts common in research and restoration. Growing kelps in closed, recirculating culture systems may address many of these constraints, yet closed system approaches have remained largely undescribed. Extensive declines of the bull kelp(Nereocystis luetkeana), an ecologically important canopy species in the Northeast Pacific, have received widespread attention and prompted numerous research and conservation initiatives. Here, we detail two approaches for cultivating N. luetkeana sporophytes in closed recirculating systems. Nereocystis luetkeana were reared as attached thalli in custom seaweed growth flumes and also free-floating in tumble culture tanks. Careful control of stocking density, water motion, aeration, and nutrient levels allowed for rapid growth and normal morphogenesis of laboratory-grown kelp. Culture systems reached up to 3 kg · m-3 , and individual thalli attained lengths of up to 6 m before the trials were terminated. Our results demonstrate the potential of recirculating, closed culture systems to overcome limitations associated with traditional culture methods. Recirculating systems enable the precise control of culture conditions, improving biosecurity and facilitating cultivar development and other research. Kelps can be grown away from the ocean or outside their native ranges, and seasonal or annual species can be produced year-round without seasonal constraints.

Effects of citrate-stabilized gold and silver nanoparticles on some safety parameters of Porphyridium cruentum biomass.

Introduction: Our research raises the question of how realistic and safe it is to use gold and silver nanoparticles in biotechnologies to grow microalgae, which will later be used to obtain valuable products. To this purpose, it was necessary to assess the influence of 10 and 20nm Au and Ag nanoparticles stabilized in citrate on the growth of microalga Porphyridium cruentum in a closed cultivation system, as well as some safety parameters of biomass quality obtained under experimental conditions. Methods: Two types of experiments were conducted with the addition of nanoparticles on the first day and the fifth day of the cultivation cycle. Changes in productivity, lipid content, malondialdehyde (MDA), as well as antioxidant activity of microalgae biomass have been monitored in dynamics during the life cycle in a closed culture system. Results: The impact of nanoparticles on the growth curve of microalgae culture was marked by delaying the onset of the exponential growth phase. A significant increase in the content of lipids and MDA in biomass was noted. Excessive accumulation of lipid oxidation products within the first 24h of cultivation resulted in altered antioxidant activity of red algae extracts. Discussion: Citrate-stabilized gold and silver nanoparticles proved to be a stress factor for red microalga Porphyridium cruentum, causing significant changes in both biotechnological and biomass safety parameters. Addition of Au and Ag nanoparticles during the exponential growth phase of porphyridium culture led to an enhanced lipid accumulation and reduced MDA values in biomass.

Bioactive compounds by microalgae and potentials for the management of some human disease conditions.

Microalgae biomasses are excellent sources of diverse bioactive compounds such as lipids, polysaccharides, carotenoids, vitamins, phenolics and phycobiliproteins. Large-scale production of these bioactive substances would require microalgae cultivation either in open-culture systems or closed-culture systems. Some of these bioactive compounds (such as polysaccharides, phycobiliproteins and lipids) are produced during their active growth phase. They appear to have antibacterial, antifungal, antiviral, antioxidative, anticancer, neuroprotective and chemo-preventive activities. These properties confer on microalgae the potential for use in the treatment and/or management of several neurologic and cell dysfunction-related disease conditions, including Alzheimer's disease (AD), AIDS and COVID-19, as shown in this review. Although several health benefits have been highlighted, there appears to be a consensus in the literature that the field of microalgae is still fledgling, and more research needs to be carried out to ascertain the mechanisms of action that underpin the effectiveness of microalgal compounds. In this review, two biosynthetic pathways were modeled to help elucidate the mode of action of the bioactive compounds from microalgae and their products. These are carotenoid and phycobilin proteins biosynthetic pathways. The education of the public on the importance of microalgae backed with empirical scientific evidence will go a long way to ensure that the benefits from research investigations are quickly rolled out. The potential application of these microalgae to some human disease conditions was highlighted.

P–143 Improved embryonic development and utilization rates with EmbryoScope: A within-subject comparison versus a benchtop incubator

Abstract Study question In consecutive intracytoplasmic sperm injection (ICSI) cycles, is embryonic development in EmbryoScope better than the previous one obtained in a benchtop (G–185) incubator? Summary answer Embryonic development, and oocyte and embryo utilization rates (OUR and EUR) are significantly improved in the EmbryoScope, as compared to G–185. What is known already The time-lapse imaging (TLI) system, which allows a non-invasive continuous assessment of embryo morphokinetics parameters in a closed culture system has been developed, promising improved embryo development by reducing oscillations in pH, humidity and temperature. To investigate this hypothesis, one study has already compared embryonic development in a TLI versus a benchtop incubator. However, It has never been investigated whether embryonic development can be improved within-subject, by changing from benchtop incubator in the first intracytoplasmic sperm injection (ICSI) cycle to the EmbryoScope, a TLI incubator, in the following ICSI cycle, and that was the objective of the present study. Study design, size, duration This study had a retrospective within-subject design, in which each cycle served as its own control. Data were obtained via chart review of patients undergoing ICSI in a private university–affiliated IVF center that fulfilled the following criteria: second ICSI attempt in which embryos had been cultured in a TLI incubator system (TLI group, n = 71), preceded by a first ICSI attempt in which embryos had been cultured in a conventional incubator (Control group, n = 71). Participants/materials, setting, methods Embryonic development up to the fifth day of development, OUR (transferred embryos plus frozen embryos per retrieved oocytes) and EUR (transferred embryos plus frozen embryos per fertilized oocytes) were compared between the groups using generalized linear models followed by Bonferroni post hoc. The post hoc achieved power was 82.6%, considering the sample size, the effect size obtained for blastocyst development rate and 5% significance level. Main results and the role of chance There were significant differences in fertilization rate (76.0% ± 1.3 vs. 80.0% ± 1.4, p = 0.044, OR: 1.051, CI: 1.001 – 1.103), non-fertilization rate (14.8% ± 0.6 vs. 6.3% ± 0.4, p < 0.001, OR: 0.424, CI: 0.370 – 0.486), day–2 non-cleavage rate (3.8% ± 0.2 vs. 1.1% ± 0.1, p < 0.001, OR: 0.285, CI: 0.234 – 0.347), blastocyst development rate (40.9% ± 1.1 vs. 55.6% ± 1.3, p < 0.001, OR: 1.358, CI: 1.267 – 1.456), frozen blastocyst rate (31.8% ± 0.8 vs. 37.0% ± 0.9, p < 0.001, OR: 1.163, CI: 1. 085 – 1.248), OUR (40.7% ± 1.0 vs. 50.2% ± 1.1, p < 0.001, OR: 1.232, CI: 1.155 – 1.314), and EUR (52.4% ± 1.1 vs. 66.6% ± 1.2, p < 0.001, OR: 1.269, CI: 1.202 - 1.341), all in favor of TLI group. Pregnancy rate (30.2% vs. 30.8%, p = 0.940), implantation rate (24.6% ± 40.0 vs. 26.1% ± 41.6, p = 0.830), and miscarriage rate (21.1% vs. 15.0%, p = 0.622) were similar between Control and TLI groups, respectively. Limitations, reasons for caution (i) Different culture dishes were used in each system; (ii) it is not possible to confirm how much of the embryonic improvement was due to the culture conditions; (iii) the study design is not ideal for the comparison of clinical outcomes and, also, underpowered to do so. Wider implications of the findings: Even though the clinical outcomes were similar between the groups, the results may also lead to higher cumulative pregnancy outcomes following embryo thawing and transfer. Trial registration number Not applicable

The Growth of Leaf Lettuce and Bacterial Communities in a Closed Aquaponics System with Catfish

Aquaponics is a circulating and sustainable system that combines aquaculture and hydroponics and forms a symbiotic relationship between fish, plants, and microorganisms. We hypothesized that feed alone could support plant growth, but the symbiosis with fish adds some beneficial effects on plant growth in aquaponics. In this study, we created three closed culture systems, namely, aquaponics, hydroponics without nitrogen (N) and phosphorus (P), and aquaculture, and added the same amount of feed containing N and P to all the treatments in order to test the hypothesis. Accumulation of NO3− and PO43− was alleviated in aquaponics and hydroponics as a result of plant uptake. Lettuce plants grown in aquaponics grew vigorously until 2 weeks and contained a constant level of N in plants throughout the production period, whereas those in hydroponics grew slowly in the early stage and then vigorously after 2 weeks with a late increment of N concentration. These results suggest that catfish help with the faster decomposition of the feed, but, in hydroponics, feed can be slowly dissolved and decomposed owing to the absence of the fish. The bacterial community structures of the culture solution were investigated using 16S rRNA gene amplicon sequencing. At the class level, Actinobacteria, Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria were the major microbial groups in the solutions. Aquaponics prevented the pollution of tank solution and maintained a higher water quality compared with hydroponics and aquaculture, suggesting that aquaponics is a more sustainable cultivation system even in a small-scale system.

Diurnal Fe(II)/Fe(III) cycling and enhanced O2 production in a simulated Archean marine oxygen oasis

The oxygenation of early Earth’s atmosphere during the Great Oxidation Event, is generally accepted to have been caused by oceanic Cyanobacterial oxygenic photosynthesis. Recent studies suggest that Fe(II) toxicity delayed the Cyanobacterial expansion necessary for the GOE. This study investigates the effects of Fe(II) on two Cyanobacteria, Pseudanabaena sp. PCC7367 and Synechococcus sp. PCC7336, in a simulated shallow-water marine Archean environment. A similar Fe(II) toxicity response was observed as reported for closed batch cultures. This toxicity was not observed in cultures provided with continuous gaseous exchange that showed significantly shorter doubling times than the closed-culture system, even with repeated nocturnal addition of Fe(II) for 12 days. The green rust (GR) formed under high Fe(II) conditions, was not found to be directly toxic to Pseudanabaena sp. PCC7367. In summary, we present evidence of diurnal Fe cycling in a simulated shallow-water marine environment for two ancestral strains of Cyanobacteria, with increased O2 production under anoxic conditions.

From frustules to medusae: A new culture system for the study of the invasive hydrozoan Craspedacusta sowerbii in the laboratory

AbstractThe invasive freshwater jellyfish Craspedacusta sowerbii, native from East Asia (Yangzi Jiang River), was introduced in Europe for the first time in the basins of the Royal Botanic Garden in London. From the beginning of the 20th century, worldwide reports of the presence of C. sowerbii have been increasing (USA, Canada, Europe, Australia, Russia). Despite its now worldwide distribution, C. sowerbii has rarely been the subject of recent studies. Moreover, C. sowerbii is difficult to rear in the laboratory, and individuals generally from the wild have only been reared for short periods. Many aspects of laboratory cultures have proven to be problematic for all stages of the life cycle (from frustule to medusae): lack of optimal growing system (circular current or not), water quality (physical and chemical conditions), diet (the type of food), and temperature. In this article, we present a technique for culturing all life stages of C. sowerbii, from polyps to medusae, to study its life history in the laboratory. To demonstrate the success of our culture protocol, the growth of polyps was measured for 80 days at 19 and 29°C. Colony growth increased at both temperatures in our culture system, and data were similar to those presented in the literature, illustrating the success of this protocol. Medusae were cultured for 70 days, and their bell diameter increased from 0.60 ± 0.08 mm (Day 0) to 9.0 ± 2.1 mm (Day 32). We developed a closed culture system that allowed specimens (i.e., polyps and medusae) to be maintained for more than 2 months (80 days for polyps, 72 days for medusae). This culture system will allow researchers in the future to study more precisely the metabolism (growth, ingestion, longevity) of polyps and medusae to understand life‐history characteristics important to this species' ecology (periods of medusae production, predation, and diet).

EFFECT OF THE GERI INCUBATOR ON CLINICAL OUTCOMES IN FRESH TRANSFER ART CYCLES

The GERI (Genea) incubator combines a closed culture system to provide stable conditions for the embryo, along with timelapse monitoring to aid selection. Although there are strong theoretical arguments that these interventions can improve outcomes, as with other “add ons“ there is limited data to demonstrate if they can actually benefit patients. Assessment of embryo morphology has traditionally required repeated removal from conventional incubators, exposing embryos to fluctuations in environment. Time-lapse Systems (TLS) such as GERI offer two potential advantages: - Assessment without the need for physical disturbance (closed culture) - Additional information regarding embryo development, acquired through continuous monitoring Although there are strong theoretical arguments that these interventions can improve clinical outcomes, there is limited data to demonstrate true benefit to patients, with a Cochrane review (2019) concluding insufficient good quality evidence of any difference between TLS and conventional incubation. Study question: Does embryo culture in the GERI system have any influcence on blastulation, implantation and pregnancy rates in fresh IVF/ICSI cycles A retrospective cohort study of all fresh IVF/ICSI blastocyst transfer cycles from Jan 2016 to Dec 2019 was performed. Cleavage stage transfer, elective freeze-all, cycles with no embryos, and female age 42+ were excluded. All treatments were in a tertiary level university affiliated reprodictive medicine centre, and 578 cycles met the inclusion criteria. Treatments were divided into those where embryo culture was in standard incubators, and those using GERI. Clinical outcomes were calculated and compared using Chi square analysis for proportions and t-test for means. Clinical Pregnancy rates were similar between groups ( 45.0% vs 38.1%, p=0.09), however significantly more embryos were transferred in the traditional incubator cases (1.44 vs 1.17, p<0.0001). There was a significantly higher implantation rate with the GERI cultured blastocysts (38.2% vs 26.1%, p =0.0004). More embryos were available for cryopreservation in the GERI cohort (p=0.0081) Although age, AMH, number of oocytes retrieved were the same between groups, the fact this this was a retrospective analysis means that bias and the impact of confounding factors cannot be excluded. The GERI system has the potential to help outcomes by the use of a closed culture system which could benefit embryo development, along with timelapse monitoring and use of morphokinetics to aid embryo selection and shorten the time to pregnancy.

Comparing transcriptome profiles of human embryo cultured in closed and standard incubators.

It is necessary to compare the transcriptomic profiles of human embryos cultured in time-lapse imaging (TLI) incubators and standard incubators (SI) in order to determine whether a closed culture system has a positive impact on embryos. In this study, we used RNA-sequencing (RNA-Seq) to characterize and compare the gene expression profiles of eight-cell embryos of the same quality grade cultured in TLI and SI. We sequenced a total of 580,952,620 reads for zygotes, TLI-cultured, and SI-cultured eight-cell embryos. The global transcriptomic profiles of the TLI embryos were similar to those of the SI embryos and were highly distinct from the zygotes. We also detected 539 genes showing differential expression between the TLI and SI groups with a false discovery rate (FDR) < 0.05. Using gene ontology enrichment analysis, we found that the highly expressed SI genes tended to execute functions such as transcription, RNA splicing, and DNA repair, and that the highly expressed TLI genes were enriched in the cell differentiation and methyltransferase activity pathways. This study, the first to use transcriptome analysis to compare SI and TLI, will serve as a basis for assessing the safety of TLI application in assisted reproductive technology.

Asymmetric Fitness of Second-Generation Interspecific Hybrids Between Ciona robusta and Ciona intestinalis.

Reproductive isolation is central to speciation, but interspecific crosses between two closely related species can produce viable and fertile hybrids. Two different species of tunicates in the same ascidian genus, Ciona robusta and Ciona intestinalis, can produce hybrids. However, wild sympatric populations display limited gene flow, suggesting the existence of obstacles to interspecific reproduction that remain unknown. Here, we took advantage of a closed culture system to cross C. robusta with C. intestinalis and established F1 and F2 hybrids. We monitored post-embryonic development, survival, and sexual maturation to characterize the genetic basis of simple traits, and further probe the physiological mechanisms underlying reproductive isolation. Partial viability of first and second generation hybrids suggested that both pre- and postzygotic mechanisms contributed to genomic incompatibilities in hybrids. We observed asymmetric fitness, whereby the C. intestinalis maternal lines fared more poorly in our system, pointing to maternal origins of species-specific sensitivity. We discuss the possibility that asymmetrical second generation inviability and infertility emerge from interspecific incompatibilities between the nuclear and mitochondrial genomes, or other maternal effect genes. This work paves the way to quantitative genetic approaches to study the mechanisms underlying genomic incompatibilities and other complex traits in the genome-enabled Ciona model.

Bio-economic analysis of super-intensive closed shrimp farming and improvement of management plans: a case study in Japan

Crustacean aquaculture is a multibillion-dollar industry worldwide that continues to show significant growth. Shrimp farming has been intensified for decades, and super-intensive closed culture systems have now been developed to improve productivity and reduce environmental burdens. Here, we used bio-economic approaches to investigate the mechanisms and economic productivity of shrimp farming. We used three steps: (1) path analysis by using structural equation models to determine the candidate factors associated with productivity; (2) modeling of population dynamics and profits; and (3) simulations based on the models to clarify the productive characteristics of a super-intensive closed culture system. Our findings suggest that the population dynamics of the system were limited by unidentified factors that differed from those found in many experimental studies, such as water temperature, salinity, dissolved oxygen, and nitrogenous waste. The unidentified factors were related to the number of days of rearing and cumulative biomass mortality. The production plan suggested by our simulation required frequent culture rotation to increase profits. Our case study provides important practical information about the characteristics of super-intensive shrimp farming, implications for efficient economic management, and new research subjects for the future.

Towards in situ continuous feeding via controlled release of complete nutrients for fed-batch culture of animal cells

Small-scale culture of animal cells in suspension is of importance for many applications. At a small-scale, fed-batch is achieved either by manual bolus feeding or the use of liquid handling robots. In this study, we report an alternate application of a hydrogel for in situ continuous delivery of a nutrient feed comprising 18 amino acids, vitamins, antioxidants, and trace elements. We show that amino acid release is sustained for at least seven days. Importantly, release rates of individual amino acids can be independently modulated by changing their loading. We demonstrate the application of this hydrogel for complete in situ feeding of nutrients to a suspension adapted CHO cell line expressing IgG leading to 2.7-fold and 4-fold improvement in integral viable cell density (IVCD) and volumetric productivity respectively. This is similar to improvements obtained by bolus liquid feeding. Further, supplying glucose from the same hydrogel to eliminate manual feeding led to a 1.8-fold increase in IVCD accompanied by a 3-fold increase in volumetric productivity as compared to batch culture. In summary, this study provides a proof-of-concept that hydrogels can enable completely closed in situ feeding for mammalian cell culture requiring no external intervention. Such continuous in situ delivery can potentially enable closed culture systems maintaining nutrients at low levels mimicking physiological concentrations.

UM171 Modified Cord Blood Achieves Excellent Survival and Disease Control after 2 Years of Follow-up in High and Very High Risk Malignancies

UM171 Modified Cord Blood Achieves Excellent Survival and Disease Control after 2 Years of Follow-up in High and Very High Risk Malignancies

Bio-economic analysis of super-intensive closed shrimp farming and improvement of management plans: a case study in Japan

Crustacean aquaculture is a multibillion-dollar industry worldwide that continues to show significant growth. Shrimp farming has been intensified for decades, and super-intensive closed culture systems have now been developed to improve productivity and reduce environmental burdens. Here, we used bio-economic approaches to investigate the mechanisms and economic productivity of shrimp farming. We used three steps: (1) path analysis by using structural equation models to determine the candidate factors associated with productivity; (2) modeling of population dynamics and profits; and (3) simulations based on the models to clarify the productive characteristics of a super-intensive closed culture system. Our findings suggest that the population dynamics of the system were limited by unidentified factors that differed from those found in many experimental studies, such as water temperature, salinity, dissolved oxygen, and nitrogenous waste. The unidentified factors were related to the number of days of rearing and cumulative biomass mortality. The production plan suggested by our simulation required frequent culture rotation to increase profits. Our case study provides important practical information about the characteristics of super-intensive shrimp farming, implications for efficient economic management, and new research subjects for the future.

Phycoremediation of paddy-soaked wastewater by indigenous microalgae in open and closed culture system

Phycoremediation; biotransformation of nutrients and or pollutants by microalgae, supports sustainable wastewater treatment, coupled with biomass production, resulting in enhanced cost savings, waste minimization, and energy conservation. A major challenge in this technique involves cultivation system to be adopted, mode of treatment and harvesting methods. Three different algal cultivation systems; polybags (PB), photobioreactors (PBR) and race way ponds (RWP) were employed for culturing an indigenous microalga, Scenedesmus obliquus in rice mill paddy-soaked wastewater (PSW). The maximum biomass productivity (BP) of 340 ± 2 mg/L/d was observed in PBR with an ammonical nitrogen (NH3-N) removal (RN) of 96.12 ± 0.21% and the phosphates (PO4-P) removal (RP) of 97.58 ± 0.18%. Highest lipids (L)∼12% (% biomass), protein (P)∼40% and carbohydrates (C)∼20%) were gained in PBR culture system, followed by RWP and PB.

Fabricating retinal pigment epithelial cell sheets derived from human induced pluripotent stem cells in an automated closed culture system for regenerative medicine.

Regenerative medicine has received a lot of attention as a novel strategy for injuries and diseases that are difficult to cure using current techniques. Cell production, which is vital for regenerative medicine, has undergone remarkable progress via breakthroughs in developmental biology and tissue engineering; currently, cell production requires numerous experimental operators performing manual, small-scale cell cultures. Other major obstacles for cell production and regenerative medicine include the variable quality of products based on the experimental procedure, the skills of operators, the level of labor required for production, and costs. Technological developments are required to overcome this, including automation instead of manual culture. Age-related macular regeneration (AMD) is a refractory ocular disease that causes severe deterioration in central vision due to senescence in the retinal pigment epithelium (RPE). Recently, we performed an autologous transplantation of induced pluripotent stem (iPS) cell-derived RPE cell sheets and started clinical research on allografts from RPE cell suspensions differentiated from iPS cells. The use of regenerative therapies for AMD using iPS cell-derived RPE is expected to become more widespread. In the present study, human iPS cell-derived RPE cells were cultured to form RPE cell sheets using equipment with a closed culture module. The quality of the automated cultured RPE cell sheets was confirmed by comparing their morphological and biological properties with those of manually generated RPE cell sheets. As a result, machine-cultured RPE sheets displayed the same quality as manually cultured RPE sheets, showing that iPS cell-derived RPE cell sheets were successfully cultured by an automated process.

CONSORTIUM OF WALLACEAN MICROALGAE IN WEST NUSA TENGGARA FOR BIODIESEL PRODUCTION

Abstract : This study aims to explore the species richness of biodiesel-producing microalgae in the waters of West Nusa Tenggara to develop renewable energy source, environmentally friendly, and not compete in land use with the agricultural sector. Microalga samples were collected from various waters in West Nusa Tenggara Province using the concentration method. Species determination  and data analysis of microalgae was carried out at the Biology Laboratory, University of Mataram to calculate the abundance of each species. The dominant species of biodiesel-producing microalgae were isolated and cultured by a closed culture system method. The oil content of the microalgae biomass produced was extracted by a liquid-liquid extraction method using n-hexane as a solvent. The results show that of the 49 species of marine microalgae identified in the waters of West Nusa Tenggara, there are 12 species of microalgae which are biodiesel producers. Of the 30 freshwater microalga species, only 8 species of microalgae are producers of biodiesel. The microalgae community of marine waters of West Nusa Tenggara is dominated by Bacteriastrumdelicatulum, B. variance, Chaetocerosaffinis, C. liciniosum, C. lorenzianum, Gyrosigma sp., Oscillatoria sp., Pseudonitzschia spp., and Thalassionemanitzschicoides, while freshwater microalgae communities are dominated by Microcystis aeruginosa, M. incerta, Nostoc sp., Pediastrumboryanum, and Staurastumcristatum. The dominant types of biodiesel-producing microalgae isolated and cultured are Chaetocerosamini, Nannochloropsisoculata and Nitzschia spp. Each cell density of C. amini, N. oculata, and Nitzschiaspp in culture 7 days after isolation was 3,600,960,000, 4,375,360,000, and 3,368,640,000 cells / liter respectively with oil content 34, 68, and 46%. Key words: biodiesel, microalgae, Wallacea, West Nusa Tenggara