Ruttnera lamellosa is a species of unicellular freshwater alga belonging to the family Chloromonadaceae. This microscopic organism is primarily found in nutrient-rich, stagnant freshwater bodies and is notable for its unique morphology and ecological role as a primary producer. While not widely studied, Ruttnera lamellosa contributes to the understanding of freshwater ecosystems and algal diversity.

Botanical Classification

• Domain: Eukaryota
• Clade: Heterokontophyta
• Class: Chrysophyceae
• Order: Chromulinales
• Family: Chloromonadaceae
• Genus: Ruttnera
• Species: Ruttnera lamellosa

Cellular Characteristics

Ruttnera lamellosa exhibits the following cellular features:

• Size: Microscopic cells, typically ranging between 10 and 30 µm in length.
• Shape: Flattened, lamellar (plate-like) morphology, from which the species derives its name.
• Flagella: Possesses two flagella, used for motility in aquatic environments.
• Chloroplasts: Contains chloroplasts for photosynthesis, giving the cells a greenish hue.
• Cell Wall: Composed of silica, providing rigidity and protection.

Habitat and Ecology

• Environment: Found in freshwater ecosystems, including ponds, lakes, and slow-moving streams. Prefers eutrophic (nutrient-rich) conditions.
• Temperature Range: Thrives in moderate to warm temperatures, but can tolerate seasonal variations.
• Role in Ecosystem:
  • Functions as a primary producer, contributing to oxygen production and serving as a food source for microorganisms and small aquatic organisms.
  • Plays a role in nutrient cycling, particularly in phosphorus-rich environments.

Chemical Composition

The biochemical profile of Ruttnera lamellosa is less explored but likely includes:

• Photosynthetic Pigments: Chlorophylls and carotenoids for photosynthesis.
• Proteins: Moderate protein content, supporting its role in aquatic food webs.
• Polysaccharides: Storage carbohydrates, possibly in the form of laminarin or related compounds.
• Silica: Essential for the composition of its cell wall.

Applications and Potential Uses

Although Ruttnera lamellosa is not widely utilized, its characteristics offer potential in various fields:

• Environmental Monitoring:

  • Useful as a bioindicator to assess the health of freshwater ecosystems, particularly in eutrophic environments.

• Ecological Studies:

  • Helps in understanding algal diversity and the ecological dynamics of freshwater ecosystems.

• Biotechnology:

  • Potential source of bioactive compounds for pharmaceuticals, though further research is needed.

How to Cultivate Ruttnera lamellosa

Cultivating Ruttnera lamellosa in a controlled environment requires specific conditions:

1. Growth Medium: Requires nutrient-enriched freshwater, with added phosphorus and nitrogen for optimal growth.
2. Light: Needs moderate light intensity to support photosynthesis.
3. Temperature: Thrives in temperatures between 15°C and 25°C.
4. Aeration: Requires gentle aeration to maintain circulation and oxygenation.
5. Harvesting: Cells can be harvested using filtration or centrifugation techniques.

Environmental and Safety Considerations

• Environmental Role:

  • Contributes to biodiversity and ecological balance in freshwater ecosystems.
  • Supports the aquatic food web by providing energy to higher trophic levels.

• Safety:

  • Non-toxic and poses no known risks to humans or animals.
  • Care should be taken to prevent excessive blooms, which could disrupt aquatic ecosystems.

References__________________________________________________________________________

Assunção, M. F., Varejão, J. M., & Santos, L. M. (2017). Nutritional characterization of the microalga Ruttnera lamellosa compared to Porphyridium purpureum. Algal research, 26, 8-14.

Abstract. Sustainable food and human health are the major concerns of the society in the last decades. Functional foods and nutraceuticals from natural sources such as microalgae are regarded as a solution. In this study the nutritional composition of Ruttnera lamellosa ACOI 339 has been evaluated and compared to the widely studied Porphyridium purpureum. R. lamellosa showed a proximate composition with 8.81% of protein and 43.88% of carbohydrate and also a convenient lack of fiber (0.94%). The strain revealed a lipid content of 2.68% with substantial amount of long chain polyunsaturated fatty acids, especially docosahexaenoic fatty acid (C22:6ω3 – DHA) representing 6.36% of total fatty acids. The intracellular polysaccharide is rich in xylose, and also a promising antioxidant capacity of 12.02 mg/L equivalent to ascorbic acid was detected as an additional feature of the valuable biomass.

Andersen, R. A., Kim, J. I., Tittley, I., & Yoon, H. S. (2014). A re-investigation of Chrysotila (Prymnesiophyceae) using material collected from the type locality. Phycologia, 53(5), 463-473.

Abstract:. We isolated 17 strains of Chrysotila stipitata and 10 strains of Chrysotila lamellosa from samples collected at exposed chalk surfaces, Westgate, Kent, England, which is the type locality for C. stipitata (generitype) and C. lamellosa. The nuclear-encoded small subunit and large subunit rRNA were used in a molecular phylogenetic analysis. We also examined the cells using light microscopy. Chrysotila stipitata had two chloroplasts per cell, as originally described, and it was positioned within the Coccolithales (Prymnesiophyceae) in a RAxML tree. Chrysotila stipitata gene sequences formed a clade with Pleurochrysis, and because Chrysotila has priority, Pleurochrysis was placed in synonymy. New nomenclatural combinations were also made. Chrysotila lamellosa was located within the order Isochrysidales, and like other members of the order, C. lamellosa had one chloroplast per cell. We reinstated the generic name Ruttnera to accommodate this species (Ruttnera lamellosa comb. nov.). We also showed that several other taxa described from the chalk cliff type locality were alternate life stages for C. stipitata, and we assigned these as synonyms of C. stipitata.

Liao, S., Yin, S., & Huang, Y. (2020, December). C 38 Ethyl Alkenoates as New Group II Isochrysidales Proxy for Detecting Mixed Alkenone Productions in Ocean Sediments. In AGU Fall Meeting Abstracts (Vol. 2020, pp. B083-08).

Abstract. Alkenones are polyunsaturated long chain methyl and ethyl ketones produced by Isochrysidales, an order of haptophyte algae. Based on phylogenetic data, members of Isochrysidales have been classified into three groups, with each group showing significant differences in temperature calibrations and preferred growth environments. Alkenones have been widely used for paleo-sea surface temperature (SST) reconstructions in the past 40 years. However, such reconstructions remain challenging in coastal areas and high latitude ocean areas due to the potential mixed alkenone productions by Group II (coastal species) and Group III (marine species) Isochrysidales. Therefore, identification of mixed alkenone productions in sediments is important for assessing corresponding reconstruction results. However, there are currently no definitive biomarkers to indicate the alkenone contribution from Group II Isochrysidales for ocean sediments where the dominant alkenone producers belong to Group III Isochrysidales. Here, we systematically examine samples from cultures of Group II (Isochrysis nuda, Isochrysis litoralis, Ruttnera lamellosa, Isochrysis galbana, Tisochrysis lutea and one strain isolated from sea ice in Baffin Bay) and Group III (Emiliania huxleyi and Gephyrocapsa oceanica) Isochrysidales and environmental samples of Group I Isochrysidales. For the first time, we report the production of C37 ethyl ester (C37OEt) and C38 ethyl ester (C38OEt) (also called alkenoates) with extended chain lengths by Isochrysidales. While C37OEt alkenoates could be found in all culture samples of Group II and Group III Isochrysidales, C38OEt alkenoates are only found in Group II Isochrysidales. Our results indicate that C38OEt alkenoates are specific biomarkers for Group II Isochrysidales, and could be easily detected with gas chromatography-mass spectrometry (GC-MS) under single ion monitoring (SIM) mode after hydrogenating corresponding samples. Importantly, the Group II strain isolated from ice has the highest production of C38OEt alkenoates (percentage of C38OEt/C37Me is ~10 times higher than that of other Group II samples), allowing easier identification of its contribution to alkenone profiles of high latitude ocean sediments and subsequent study of environmental changes (e.g., temperature, sea ice).

Kaiser, J., van der Meer, M. T., & Arz, H. W. (2017). Long-chain alkenones in Baltic Sea surface sediments: new insights. Organic Geochemistry, 112, 93-104.

Abstract. C37 alkenones produced by certain haptophytes of the Isochrysidales are valuable sedimentary biomarkers used to estimate sea surface temperature (SST) in the open ocean. However, in coastal seas the role of salinity gradients on alkenone producing species and SST estimates is poorly known. Alkenones were analyzed in surface sediments from the marine Skagerrak region and the entire brackish Baltic Sea. Three types of alkenone distribution patterns were identified: type A distribution, which resembles the distribution in Emiliania huxleyi, type B distribution, which is similar to Ruttnera lamellosa, Isochrysis galbana and Pseudoisochrysis paradoxa distributions, although these haptophytes are absent from the Baltic Sea, and type C distribution, which is also found in worldwide lake sediments. These types of distribution are apparent in the percentage of C37:4 alkenone (%C37:4), which is significantly negatively correlated to sea surface salinity (SSS). The distribution of alkenones very likely results from distinct alkenone-producing haptophytes, whose spatial distribution is ultimately related to SSS, as supported by the hydrogen isotope fractionation (α) between alkenones and water .....