Alkaline and acid phosphatases of the marine diatoms Chaetoceros affinis var. willei (Gran) Hustedt and Skeletonema costatum (Grev.) Cleve

1975 ◽  
Vol 19 (3) ◽  
pp. 217-226 ◽  
Author(s):  
Mona Møller ◽  
Sverre Myklestad ◽  
Arne Haug
Keyword(s):  
Skeletonema Costatum ◽  
Acid Phosphatases ◽  
Marine Diatoms ◽  
Alkaline And Acid Phosphatases

Influence of the Insecticide Diflubenzuron (Dimilin) on the Growth of Marine Diatoms and a Harpacticoid Copepod in Culture

1985 ◽  
Vol 42 (7) ◽  
pp. 1272-1277 ◽  
Author(s):  
N. J. Antia ◽  
P. J. Harrison ◽  
D. S. Sullivan ◽  
T. Bisalputra
Keyword(s):  
Skeletonema Costatum ◽  
Harpacticoid Copepod ◽  
Adult Survival ◽  
Thalassiosira Weissflogii ◽  
Marine Diatoms ◽  
Tigriopus Californicus ◽  
Per Se ◽  
Juvenile Development ◽  
Cyclotella Cryptica ◽  
Injurious Effects

Diflubenzuron (Dimilin) was tested, in the concentration range 0.1–5000 μg∙L−1, for possible injurious effects on the growth and photosynthesis of three chitin-producing (Thalassiosira weissflogii, T. norden-skioldii, Cyclotella cryptica) and one nonchitinaceous (Skeletonema costatum) diatoms. For comparison, the effects of the pesticide were also examined on adult survival and juvenile development of the harpacticoid copepod Tigriopus californicus. While the development of the copepod was hindered at concentrations of the order of 1–10 μg∙L−1, the diatoms were barely affected by Dimilin even at the highest concentration tested (5 mg∙L−1). We conclude that Dimilin acts specifically on insects and crustaceans as a larvicide by interfering with chitin deposition into cuticles during juvenile development through ecdysis. The lack of effect from Dimilin on the chitin-producing diatoms has suggested that the insecticide may not inhibit chitin biosynthesis per se as was previously believed, but that it presumably deregulates one or more of the larval postsynthetic processes responsible for chitin integration into cuticles.

The ultrastructure and histochemistry of the cyst wall of Bucephalus haimeanus (Lacaze-Duthiers, 1854)

Parasitology ◽  
1977 ◽  
Vol 75 (2) ◽  
pp. 207-214 ◽  
Author(s):  
Jacqueline C. Higgins ◽  
D. E. Wright ◽  
R. A. Matthews
Keyword(s):  
Cyst Wall ◽  
Protein Complexes ◽  
Middle Layer ◽  
Outer Edge ◽  
Acid Phosphatases ◽  
Free Aldehyde ◽  
Aldehyde Groups ◽  
And Function ◽  
Cyst Cavity ◽  
Alkaline And Acid Phosphatases

Metacercarial cysts of Bucephalus haimeanus occur throughout the liver of Pomatoschistus microps, greater concentrations being found around the gall bladder, blood vessels and periphery of the liver. The cyst wall is composed of three layers, an inner granular, middle vacuolated and outer nucleated layer. The inner layer consists of three zones, an inner zone of irregularly compacted, granular material; a middle densely compacted zone and an outer moderately compacted zone. Vacuoles of the middle layer vary in appearance and appear to be discharging their contents into the cyst cavity. The cells of the outer layer are flattened and elongated with elongate nuclei but no other distinct organelles. Occasionally at the outer edge of the cyst are electron-dense cells which are in the process of degeneration. Only small amounts of collagen and very few leucocytes are associated with the cysts.The cyst wall is carbohydrate in nature containing some free aldehyde groups, galactogen and neutral mucosubstances. The inner layer appears to consist of mainly acidic mucopolysubstances and weakly acidic sulphomucins. Large amounts of protein, carbohydrate-protein complexes and DNA are also present within the cyst wall. Alkaline and acid phosphatases, ATPase, β-glucuronidase and N-acetyl-β-glucosaminidase were detected. The origin and function of the cyst wall is discussed.

Use of a Self-Cleaning, In-line Filter to Continuously Monitor Phytoplankton Nutrient Uptake Rates

1984 ◽  
Vol 41 (3) ◽  
pp. 540-544 ◽  
Author(s):  
J. S. Parslow ◽  
P. J. Harrison ◽  
P. A. Thompson
Keyword(s):  
Nutrient Uptake ◽  
Uptake Rate ◽  
Skeletonema Costatum ◽  
Thalassiosira Pseudonana ◽  
Ammonium Concentration ◽  
Marine Diatoms ◽  
Response Characteristics ◽  
Uptake Rates ◽  
Laboratory Cultures ◽  
Self Cleaning

Our new technique allows the decline in ambient ammonium concentration to be followed continuously during phytoplankton uptake experiments. A self-cleaning, in-line filter permits the continuous separation of cells from the medium for nutrient determination by an autoanalyzer. The technique works well with laboratory cultures of the marine diatoms Thalassiosira pseudonana and Skeletonema costatum. Changes in uptake rate on time scales of 1 min or longer can be resolved, the resolution being limited by the response characteristics of the autoanalyzer.

Effect of cadmium and aluminum on bone alkaline and acid phosphatases

1983 ◽  
Vol 31 (4) ◽  
pp. 386-390 ◽  
Author(s):  
Naoki Sugawara ◽  
Terukazu Sadamoto ◽  
Chieko Sugawara
Keyword(s):  
Acid Phosphatases ◽  
Alkaline And Acid Phosphatases

Soil microbial activity as influenced by compaction and straw mulching

2012 ◽  
Vol 26 (1) ◽  
pp. 65-69 ◽  
Author(s):  
A. Siczek ◽  
M. Frąc
Keyword(s):  
Microbial Activity ◽  
Soil Compaction ◽  
Soil Microbial Activity ◽  
Acid Phosphatases ◽  
Compacted Soil ◽  
Straw Mulching ◽  
Soil Microbial ◽  
Total Bacteria ◽  
Alkaline And Acid Phosphatases ◽  
Stimulation Of

Soil microbial activity as influenced by compaction and straw mulchingField study was performed on Haplic Luvisol soil to determine the effects of soil compaction and straw mulching on microbial parameters of soil under soybean. Treatments with different compaction were established on unmulched and mulched with straw soil. The effect of soil compaction and straw mulching on the total bacteria number and activities of dehydrogenases, protease, alkaline and acid phosphatases was studied. The results of study indicated the decrease of enzymes activities in strongly compacted soil and their increase in medium compacted soil as compared to no-compacted treatment. Mulch application caused stimulation of the bacteria total number and enzymatic activity in the soil under all compaction levels. Compaction and mulch effects were significant for all analyzed microbial parameters (P<0.001).

Role of oesophageal glands in the digestive physiology of two rumen amphistomesOrthocoelium scoliocoeliumandParamphistomum cervi

1983 ◽  
Vol 57 (1) ◽  
pp. 11-20 ◽  
Author(s):  
P. N. Sharma ◽  
C. Hora
Keyword(s):  
Chemical Composition ◽  
Hydrolytic Enzymes ◽  
Acid Phosphatases ◽  
Digestive Physiology ◽  
Cathepsin C ◽  
Oesophageal Gland ◽  
Paramphistomum Cervi ◽  
Alkaline And Acid Phosphatases

AbstractHistochemical techniques have been used to study the chemical composition of the oesophageal gland secretions ofOrthocoelium scoliocoeliumandParamphistomum cervi. Results suggest that the secretions contain numerous enzymes, e.g., non-specific alkaline and acid phosphatases, ATPase, TPPase, esterase (Cathepsin C like), β-galactosidase, β-glucuronidase and N-acetyl-β-glucosaminidase. The role of these enzymes in the digestion of food in these amphistomes is discussed.On the basis of histological and histochemical studies the caecal epithelium of the two amphistomes has been found to be syncytial bearing regularly arranged numerous, long but equal-sized and closely packed cylindrical microvilli. The role of various hydrolytic enzymes in well fed and starved flukes in relation to their gastrodermis and microvilli has also been discussed.

Sign in / Sign up

Export Citation Format

Share Document