Energy Reserve Lipids of Zooplanktonic Crustaceans from an Oligotrophic Saline Lake In Relation to Food Resources and Temperature

1993 ◽  
Vol 50 (11) ◽  
pp. 2404-2420 ◽  
Author(s):  
Michael T. Arts ◽  
Richard D. Robarts ◽  
Marlene S. Evans
Keyword(s):  
Lipid Content ◽  
Saline Lake ◽  
Time Lag ◽  
Algal Species ◽  
Daphnia Pulex ◽  
Energy Reserve ◽  
Wild Populations ◽  
Or Groups ◽  
Salinity Levels ◽  
Reserve Lipid

In three zooplankton species examined over a 2-yr period in an oligotrophic saline (22 g∙L−1) lake, triacylglycerols (energy reserve lipids) were the most abundant lipid class followed by phospholipids and sterols. Marked seasonal differences in patterns of total and energy reserve lipid content in the herbivorous calanoid Leptodiaptomus sicilis were correlated with temporal patterns in edible algal biomass and temperature. The appearance of particular algal species, or groups of similar-sized species, occurred synchronously with changes in lipid content of both L. sicilis and Daphnia pulex. These periods of changing lipid content were used to infer nutritional suitability or inadequacy (unavailability) of specific algae for wild populations of zooplankton. Energy transfer from phytoplankton to the carnivorous calanoid Hesperodiaptomus nevadensis through L. sicilis involved a time lag of approximately 1–2 mo; this was hypothesized to result from a feeding dependency on L. sicilis copepodites due to a gape limitation of the predator. Demographics of D. pulex in this lake were unusual because the species was consistently absent during spring. In addition, total lipids and triacylglycerols were low (<15% and <4.5 μg∙animal−1, respectively), suggesting that D. pulex had been pushed into a subsistence niche by the rising salinity levels.

Integrated Dairy Plant Effluent Treatment and Production of Biomass and Lipids using Micro Algae - "Chlorella vulgaris"

2012 ◽  
Vol 10 (1) ◽  
Author(s):  
Bharathiraja Balasubramaniyan ◽  
Jayamuthunagai Jayaraman
Keyword(s):  
Chlorella Vulgaris ◽  
Lipid Content ◽  
Research Work ◽  
Algal Species ◽  
Oxygen Demand ◽  
Effluent Treatment ◽  
Toxic Substances ◽  
Pure Strain ◽  
Treated Effluent ◽  
High Lipid

Abstract Algal biomass is a potentially inexpensive source of energy which has high lipid content. As India is the Asia’s largest milk producing country (104.8 million tons in the year 2008), the milk production terminates with an effluent production of 5.24% of the total milk produced i.e., 20 million tons of dairy waste is produced. This effluent can be broken down in many ways, but a more economical way is broken down by the growth of the algal species Chlorella vulgaris which results in the tremendous reduction in various toxic salts concentration and other complex chemicals. As the dairy effluent is hostile to the natural environment, the algae is used not only to break down the toxic substances but also to produce Biomass, which is produced at a rate of 17g/l, which contains a lipid content of 30% ( from 1:1 ratio of effluent and water). Also the treated effluent has low chemical oxygen demand [COD], hence this can be used for irrigation of farms mainly those which are heavily fed with chemical fertilizers. The biosynthesis of organics salts, alkanoates [PHAs] and other phenolic compounds, involves algal species the process is secured by using i) large inoculums ii) tolerant strain (pure strain or GM, if available). This research work uses the pure strain of Chlorella vulgaris which involves the treatment of effluent with three different dilutions and analyzing them.

Differential filtration efficiencies of Daphnia pulex

1982 ◽  
Vol 60 (9) ◽  
pp. 2129-2133 ◽  
Author(s):  
Richard A. Osgood
Keyword(s):  
Algal Species ◽  
Daphnia Pulex ◽  
Chlorella Pyrenoidosa ◽  
Radioactive Label ◽  
Ankistrodesmus Falcatus ◽  
Filtration System ◽  
Food Concentrations ◽  
Feeding Trials ◽  
Filtering Rates ◽  
Differential Filtration

When three green algae Chlorella pyrenoidosa, Ankistrodesmus falcatus, and Closterium acerosum (Chlorophyta) were presented to Daphnia pulex in a mixture, these cells were ingested differentially; filtering rates were 1.30, 2.79, and 7.53 mL∙animal−1 h−1, respectively. Filtration rates on each of these algal species presented singly at equivalent (biovolume) food concentrations were not significantly different (p > 0.05) from the rates measured in a mixture. The algal cells for the feeding trials were individually labeled with metal tracers (Fe, Mn, and Zn) and this technique is compared with a radioactive label (32P). The differential filtration efficiencies are viewed as a passive selection mechanism resulting in preferential ingestion of larger food cells and is simply related to the physical properties of Daphnia's filtration system.

scholarly journals A synergic approach for nutrient recovery and biodiesel production by the cultivation of microalga species in the fertilizer plant wastewater

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Indu Ambat ◽  
Sabina Bec ◽  
Elina Peltomaa ◽  
Varsha Srivastava ◽  
Anne Ojala ◽  
...  
Keyword(s):  
Lipid Content ◽  
Algal Species ◽  
Acid Methyl Ester ◽  
Biomass Concentration ◽  
Biomass Productivity ◽  
Biodiesel Production ◽  
Freshwater Microalgae ◽  
Fertilizer Plant ◽  
Solvent Extraction Method

AbstractThe combination of wastewater treatment and biodiesel production using algal cultivation was studied in the present work. The two main goals of the work were achieved by the cultivation of freshwater microalgae such as Chlamydomonas sp., Scenedesmus ecornis, and Scenedesmus communis in two different dilutions of fertilizer plant wastewater (FWWD1 and FWWD2) collected from Yara Suomi Oy, Finland. The growth pattern of different algal species in FWWD1 and FWWD2 was observed. The effect of pH on biomass concentration, lipid content, biomass productivity, and lipid productivity by all three algal species in FWWD1 and FWWD2 were monitored. The maximum biomass concentration and productivity were observed in FWWD1 at pH7.5 for Chlamydomonas sp. and at pH 8.5 for S. ecornis and S. communis. The maximum lipid content was detected in Chlamydomonas sp at pH5.5, followed by S. ecornis and then S. communis at pH 7.5 in FWWD2 obtained after co-solvent extraction method. The most significant removal percentage of COD by all algal species were observed in FWWD1, whereas the highest removal percentage of TN and TP were detected in FWWD2, respectively. The fatty acid methyl ester (FAME) characterization of each algal species in FWWD1 and FWWD2 at their optimum pH was investigated to determine the quality of obtained biodiesel.

Experimental Observations on the Effects of Predation by Goldfish (Carassius auratus) on the Zooplankton of a Small Saline Lake

1975 ◽  
Vol 32 (9) ◽  
pp. 1589-1594 ◽  
Author(s):  
Chris P. Archibald
Keyword(s):  
Carassius Auratus ◽  
Saline Lake ◽  
Daphnia Pulex ◽  
Fish Predation ◽  
Field Studies ◽  
Minimum Size ◽  
Size Distributions ◽  
Short Term ◽  
Goldfish Carassius Auratus ◽  
Zooplankton Communities

The short-term effects of various intensities offish predation on zooplankton communities were examined. Field studies indicated that fish predation was, as expected, size-selective: in the presence of fish, size distributions of the principal prey, Daphnia pulex, were skewed toward the smaller size-classes and the minimum size of egg-bearing D. pulex was also smaller. Fecundity of Diaptomus ashlandi, and probably also of Daphnia pulex, was greater with fish present. This caused the abundance of these two dominant species to increase initially with increasing predation. Subsequently, the species declined at higher predation levels in order of their interest to fish, with large D. pulex[Formula: see text] declining before small D. pulex (< 1.35 mm) and both groups doing so at lower predation levels than Diaptomus ashlandi.

A rapid method for the estimation of mean dry weight and lipid content of the infective juveniles of entomopathogenic nematodes using image analysis

Nematology ◽  
1999 ◽  
Vol 1 (6) ◽  
pp. 655-660 ◽  
Author(s):  
Lihong Qiu ◽  
Robin Bedding
Keyword(s):  
Image Analysis ◽  
Body Size ◽  
Lipid Content ◽  
Entomopathogenic Nematodes ◽  
Dry Weight ◽  
Video Camera ◽  
Energy Reserve ◽  
Cross Sectional ◽  
Computerised Image Analysis ◽  
Area X

AbstractA method using computer image analysis for the estimation of dry weight, lipid content, body size and length of individual infective juveniles (IJ) of entomopathogenic nematodes (EN) is described. Images of IJ, captured using a video camera, were digitalised and transferred to a computer for analysis. The longitudinal cross-sectional area of the nematode (Area), mean grey level (MGL) and perimeter of the nematode image (Perimeter) were measured automatically. Nematode samples having a range of sizes, mean dry weights and lipid contents, as well as a series of samples of different ages were examined. It was found that: i) the index Area x MGL correlates well with the mean dry weight of the nematode, which is in turn a good indicator of the total energy reserve of the nematodes; ii) MGL correlates well with the lipid content (as % dry weight) which is a good indicator of the quality of the energy reserve; and iii) the perimeter of the nematode image can be used to estimate the length of an IJ. Compared to currently available methods, such as direct measurement of mean dry weight or lipid content, computerised image analysis gives more information concerning the samples tested and enables variations in dry weight, lipid content, body size and length between individual IJ to be estimated readily. A sample of 30 IJ can be examined in 30 to 60 min making this method ideal for quality control during production, processing, formulation and storage of EN-based biopesticide products. Methode rapide pour l'estimation du poids sec et du contenu lipidique moyens des juveniles infestants de nematodes entomopathogenes basee sur l'analyse d'images - Il est decrit une methode utilisant l'analyse numerisee d'images et permettant l'estimation du poids sec, du contenu lipidique, de la taille et de la longueur du corps des juveniles infestants (IJ) de nematodes entomopathogenes. Les images des IJ, saisies par video-camera, sont digitalisees et transferees pour analyse sur ordinateur. La surface de la coupe longitudinale du nematode (Area), le niveau moyen d'opacite (MGL) et le perimetre de l'image du nematode (Perimeter) sont mesures automatiquement. Des echantillons de nematodes de taille, de poids sec et de contenu lipidique varies ainsi qu'une serie representant differents ages ont ete examines. Il a ete constate que: i) l'index Area x MGL est bien correle au poidsmoyen du nematode, lequel represente un bon indicateur de la reserve energetique totale du nematode; ii) MGL est bien correle au contenu lipidique (en % du poids sec), bon indicateur de la qualite de la reserve energetique; iii) le perimetre de l'image peut etre utilise pour estimer la longueur des IJ. Comparee aux methodes couramment utilisees- telle la mesure directe du poids sec et du contenu lipidique moyens - l'analyse numerisee des images donne une meilleure information sur les echantillons testes et permet une estimation rapide des variations individuelles du poids sec, du contenu lipidique, de la taille et de la longueur des IJ. Un echantillon de 30 IJ peut etre examine en 30 a 60 min ce qui rend cette methode ideale pour les controles de qualite pendant la production, les traitements, la formulation et le stockage des produits biopesticides a base de nematodes entomopathogenes.

Lipid Mobilization in Dormant and Nondormant Caryopses of Yellow Foxtail (Setaria lutescens)

Weed Science ◽  
1983 ◽  
Vol 31 (1) ◽  
pp. 28-36 ◽  
Author(s):  
Fredric R. Lehle ◽  
David W. Staniforth ◽  
Cecil R. Stewart
Keyword(s):  
Lipid Content ◽  
Aleurone Layer ◽  
Lipid Bodies ◽  
Fresh Weight ◽  
Spherical Average ◽  
Fresh Weight Basis ◽  
Lipid Mobilization ◽  
Isopropanol Extract ◽  
Delayed Initiation ◽  
Reserve Lipid

The major reserve lipid of yellow foxtail [Setaria lutescens(Weigel) Hubb.] caryopses is triacylglyceride stored in lipid bodies. Lipid bodies are heavily concentrated in the cells of the embryo axis, scutellum, and aleurone layer and are roughly spherical (average diam 0.5μm). Percentage lipid (hot isopropanol extract) on a fresh-weight basis of mature, unimbibed seed and caryopses collected locally was about 6.4 and 11%, respectively. About 95% of the total (0.23 mg/caryopsis) was saponifiable and distributed among fatty acid classes as follows: 16:0, 5.8%; 18:0, 1.5%; 18:1, 16.2%; 18:2, 73.7%; and 18:3, 2.8%. In nondormant caryopses, saponifiable lipid content declined (18:1 and 18:2 only) about 23% during the first 6 days after imbibition in the dark at 25 C. This modest decline was preceded by the appearance of an alkaline lipase at about 24 h after the onset of imbibition. Free fatty acids accumulated during these early stages of germination and accounted for about 22% of the total saponifiable lipid remaining (0.17 mg/caryopsis) 6 days after the onset of imbibition. Lipid content and lipase activity did not change in dormant caryopses treated similarly. The delayed initiation of lipid mobilization in germinating caryopses suggests that triacylglyceride degradation is not a pivotal metabolic pathway controlling dormancy.

Membrane fluidity and lipid content of human spermatozoa selected by swim-up method

2001 ◽  
Vol 24 (6) ◽  
pp. 327-334 ◽  
Author(s):  
A. Force ◽  
G. Grizard ◽  
M. N. Giraud ◽  
C. Motta ◽  
B. Sion ◽  
...  
Keyword(s):  
Membrane Fluidity ◽  
Lipid Content ◽  
Human Spermatozoa

Lipid content of the test meal modifies the result of 13C-acetate breath test

2001 ◽  
Vol 120 (5) ◽  
pp. A466-A466
Author(s):  
H KUSUNOKI ◽  
K HARUMA ◽  
J HATA ◽  
K FUTAGAMI ◽  
M HARA ◽  
...  
Keyword(s):  
Lipid Content ◽  
Test Meal ◽  
Breath Test
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