In vivo fluorescence, extracted fluorescence, and chlorophyll concentrations in algal mass measurements

Tunzi, Milton G.; Chu, Margaret Y.; Bain, Richard C.

doi:10.1016/0043-1354(74)90121-3

Cited by 20 publications

(6 citation statements)

References 8 publications

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“…Fluorescence is the most sensitive technique for measuring low concentrations of chlorophyll and has been widely used for studying the distribution of phytoplankton in nature [23]. More recently, in vivo fluorescence has been applied to laboratory experiments as a means of determining algal growth [24–26]. Fluorescence has applications in other assays (e.g., biomarker assays such as cytochrome P450); therefore, the instruments may become more widely available as environmental laboratories expand their testing capabilities.…”

Section: Resultsmentioning

confidence: 99%

Modifications to the algal growth inhibition test for use as a regulatory assay

Geis¹,

Fleming

Korthals

et al. 2000

Enviro Toxic and Chemistry

114

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Abstract-Biological assays using aquatic invertebrates and fish do not necessarily predict protection levels for primary producers such as algae and aquatic macrophytes. State regulatory programs may not be protecting the environment from many phytotoxic compounds. Recent modifications of the U.S. Environmental Protection Agency's algal test were evaluated for their potential use as a regulatory assay. Primary goals of this investigation were to downsize the algal assay and to evaluate various methods of automation. Disposable microplates with 2-ml sample wells were evaluated as an alternative testing chamber for the 96-h growth inhibition test with Raphidocelis subcapitata (formerly known as Selenastrum capricornutum). We compared the standardized Erlenmeyer flask test to the microplate test using CuCl 2 , NaCl, phenol, ZnCl 2 , and a surfactant. We noted improved control performance with the microplate test, whereas median inhibitory concentration values were similar for both methods. Other procedures we addressed included the use of EDTA, filtration of samples, and the effect of colored samples on algal growth. We also evaluated growth estimates by comparing manual cell counting to more automated growth estimates using fluorescence and absorbance endpoints. The use of fluorescence and absorbance measurements demonstrated reductions in replicate variability over manual counting and may offer time-saving alternatives for laboratory analysts.

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Section: Resultsmentioning

confidence: 99%

Modifications to the algal growth inhibition test for use as a regulatory assay

Geis¹,

Fleming

Korthals

et al. 2000

Enviro Toxic and Chemistry

114

View full text Add to dashboard Cite

show abstract

“…Since the description of a method for the measurement of in vivo chl concentration using the ability of this molecule to fluoresce (Lorenzen 1966), this optical property has been scarcely used for the estimation of algal growth (Thomas 1970, Hannan and Patouillet 1972, Tunzi et al 1974, Paasche 1977, Brand and Guillard 1981, Sugg and VanDolah 1999). Although the development of modified fluorometers of extreme sensitivity for in vivo measurements makes the detection of low chl concentrations practicable, the accurate assessment of biomass through this parameter has been recognized as limited because it varies with growth conditions and physiological state of cells (Kiefer 1973a, Slovacek and Bannister 1973, Slovacek and Hannan 1977, Mitchell and Kiefer 1988, Sosik et al 1989, Sosik and Mitchell 1991) and among species (Lorenzen 1966, Strickland 1968, Kiefer 1973b).…”

Section: Discussionmentioning

confidence: 99%

REAPPRAISAL OF PHYSIOLOGICAL ATTRIBUTES OF NINE STRAINS OF DUNALIELLA (CHLOROPHYCEAE): GROWTH AND PIGMENT CONTENT ACROSS A SALINITY GRADIENT

Cifuentes

González

Inostroza

et al. 2001

Journal of Phycology

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Among the few taxonomic characters used to circumscribe sections within the subgenus Dunaliella are the physiological response to changes in salt concentration, which define a specific range for optimal growth, and the carotenogenic ability of the vegetative cells, responsible for the change in cell color from green to orange or red, under suboptimal culture conditions. Previous work based on molecular data from seven taxa of different sections of the subgenus showed no correlation between the genetic relationship inferred from the internal transcribed spacer RFLP data and the morphophysiological attributes in use in taxonomy. The present work was performed to experimentally reevaluate the physiological attributes in the same seven previous taxa ( D. tertiolecta Butcher UTEX 999 and CCMP 1320, D. parva Lerche UTEX 1983 and CCMP 362, D. salina Teodoresco UTEX 200, D. viridis Teodoresco CONC 002, and D. peircei Nicolai et Baas Becking UTEX 2192) adding D. parva CCAP 19/9 and D. pseudosalina Massyuk et Radchenko CONC 010. Growth responses and pigment content in a wide range of NaCl concentrations were assessed. The results revealed that two strains of D. parva , two strains of D. tertiolecta , and one strain of D. peircei showed similarity in their growth responses to the whole range of salt concentrations. Dunaliella parva UTEX 1983, on the other hand, showed a growth rate pattern very different from those of their conspecifics and similar to those of D. viridis CONC 002 and D. salina UTEX 200. In relation to the pigment content, none of the strains turned orange or red in color under the whole range of salt concentrations assayed, and the total carotenoids to chlorophyll ratios were always lower or equal to 1.0. These results reaffirm the validity of the physiological attributes used to discriminate sections within the subgenus Dunaliella and show correlation with the previous molecular data, but stress the need for relocating some strains into different sections.

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“…However, in vivo fluorescence (Turner Designs, Mountain View, California) values clearly demonstrated differences in the phytoplankton component of water column solids. In vivo photosynthetic pigment fluorescence is a unitless measure which can be related to cell count and/or chlorophyll-a (Tunzi et al 1974). Fluorescence was an order of magnitude higher in ponds than in inlet water and increased with decreased water exchange or increased stocking density.…”

Section: Water Quality Of Inlet Water and Various Water-exchangehtomentioning

confidence: 99%

Effect of Water Exchange Rate on Production, Water Quality, Effluent Characteristics and Nitrogen Budgets of Intensive Shrimp Ponds

Hopkins¹,

Hamilton²,

Sandier³

et al. 1993

J World Aquaculture Soc

225

108

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Water exchange is routinely used in shrimp culture. However, there are few, if any, systematic investigations upon which to base exchange rates. Furthermore, environmental impacts of pond effluent threaten to hinder further development of shrimp farming in the U.S. The present study was designed to determine effects of normal (25.0%/d), reduced (2.5%/d) and no (0%/d) water exchange on water quality and production in intensive shrimp ponds stocked with Penaeus setiferus at 44 postlarvae/m2. Additional no‐exchange ponds were stocked with 22 and 66 postlarvae/m2 to explore density effects. Water exchange rates and stocking density influenced most water quality parameters measured, including dissolved oxygen, pH, ammonia, nitrite, nitrate, Kjeldahl nitrogen, soluble orthophosphate, biochemical oxygen demand, phytoplankton and salinity. Reduced‐exchange and no‐exchange treatments resulted in reduced potential for environmental impact. Mass balance of nitrogen for the system indicates that 13–46% of nitrogen input via feed is lost through nitrification and atmospheric diffusion. Growth and survival were excellent in ponds with normal exchange, reduced exchange, and a combination of low density with no water exchange. A combination of higher stocking density and no water exchange resulted in mass mortalities. Mortalities could not be attributed to a toxic effect of any one water quality parameter. Production was 6,400 kg/ha/crop with moderate stocking density (44/m2) and reduced (2.5%/d) water exchange and 3,200 kg/ha/crop with lower stocking density (22/m2) and no water exchange. Results indicate that typical water exchange rates used in intensive shrimp farms may be drastically reduced resulting in a cost savings to farms and reduced potential for environmental impact from effluent.

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In vivo fluorescence, extracted fluorescence, and chlorophyll concentrations in algal mass measurements

Cited by 20 publications

References 8 publications

Modifications to the algal growth inhibition test for use as a regulatory assay

Modifications to the algal growth inhibition test for use as a regulatory assay

REAPPRAISAL OF PHYSIOLOGICAL ATTRIBUTES OF NINE STRAINS OF DUNALIELLA (CHLOROPHYCEAE): GROWTH AND PIGMENT CONTENT ACROSS A SALINITY GRADIENT

Effect of Water Exchange Rate on Production, Water Quality, Effluent Characteristics and Nitrogen Budgets of Intensive Shrimp Ponds

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