Effect Of Nutrient Supplementation Research Articles

Nutrient limitation in the giant clam-zooxanthellae symbiosis: effects of nutrient supplements on growth of the symbiotic partners

The effect of ammonium (5, 10 μM N) and phosphate (2, 5, 10 μM P) on the growth of the giant clam Tridacna gigas and its symbiotic dinoflagellate Symbiodinium sp. was examined. A 3 mo exposure to these nutritients significantly increased the N or P composition of the soft tissues, as reflected in a corresponding change in C:N:P ratio. Furthermore, exposure to N or N+P markedly increased the amount of soft tissue, but P alone did not, demonstrating that increased availability of inorganic nitrogen enhances tissue growth of the clam host. With addition of N, or N+P, there was a significant increase in the total number of zooxanthellae per clam, with a corresponding decrease in chlorophyll a (chl a) content per zooxanthella. However, only with N+P was there an increase in the zooxanthellae mitotic index. The inverse relationship between zooxanthellae number and chl a per zooxanthella is consistent with phytoplankton studies indicating conditions of nutrient-limitation. Furthermore, the unaffected C:N:P composition of the zooxanthellae and their relatively low specific-growth rates (4 to 10%) also suggest that they are nutrient-limited in vivo. In particular, their high mean C:N:P ratio of 303:52:1 indicates that, relative to C, they are much more depleted in P and less in N than are free-living phytoplankton. Furthermore, polyphosphates (phosphate reserves) were undetectable, and the activity levels of acid phosphatase in the zooxanthellae were relatively high and not influenced by the host's exposure to increased P concentrations in the sea water, implicating the clam host in active regulation of P availability to its symbiotic algae. This is strong evidence that N-limitation of clam zooxanthellae is a function of the availability of ammonium to the symbiosis while, irrespective of nutrient levels in sea water, clam zooxanthellae still show characteristics of P-limitation.

The effect of nutrient supplementation on the biofiltration removal of butanal in contaminated air

Butanal is one of the odorous compounds produced in the animal-rendering and food-processing industries and also in sewage-treatment plants. It shows the necessity for complementing such plants with systems for off-gas treatment. Biofiltration using simple packing material was tested for the removal of butanal. Excellent results were obtained when the filters operated at optimal humidity and were supplemented with inorganic nutrients. Without nutrients, butyric acid was detected in the effluent gas, which may explain the lower efficiency of filters without nutrients. Under optimal conditions an elimination of around 90 g·m−3·h−1 was reached.

The Effect of Nutrient Supplements on High Risk Long Term Care Residnets Receiving Pureed Diets

This study assessed the change in nutritional intake and status of 15 nursing home residents receiving a pureed diet along with commercial supplements over a 6 month period. The nutritional supplements were well accepted with a significant increase in the energy and nutrient intake after their addition. Gastrointestinal distress was measured by stool size and number. The mean number of stools increased over the 6 month period with the stool sizes remaining relatively the same. Decubitus status was monitored and seven of the ten residents who had some form of decubiti demonstrated signs of complete or partial healing. After three and six months of supplementation hematocrit and serum albumin levels significantly increased.

Are symbiotic algae nutrient deficient?

The evidence for the hypothesis that symbionts in alga−invertebrate associations are nutrient deficient is critically evaluated. It is suggested that the evidence is not consistent with algal symbionts being nutrient deficient, but is consistent with the host regulating its population of symbionts by restricting their supply of nutrients. This distinction is due to the substantial release of photosynthate by symbiotic algae and suggests that there are (at least) two distinct regulatory components involved in the characteristics of nutrient-deficient algal cells.

Effect of Nutrient Supplementation on Flavor, Quality, and Shelf Life of the Cultivated Mushroom, Agaricus bisporus

SpawnMate II supplemented at spawning increased the yield of mushrooms, while safflower oil supplemented at casing reduced mushroom yield. Nutrient supplementation did not affect solids, lipid, 1-octen-3-ol content, or fatty acid composition of mushrooms. Supplementation at casing resulted in better color for the first two flushes of the crop cycle. The 1-octen-3-ol content of mushrooms decreased during postharvest storage. Use of nutrient supplementation also affected color and maturity of mushrooms during storage.

Effect of Nutrient Supplementation on Flavor, Quality, and Shelf Life of the Cultivated Mushroom,Agaricus Bisporus

SpawnMate II supplemented at spawning increased the yield of mushrooms, while safflower oil supplemented at casing reduced mushroom yield. Nutrient supplementation did not affect solids, lipid, l-octen-3-ol content, or fatty acid composition of mushrooms. Supplementation at casing resulted in better color for the first two flushes ofthe crop cycle. The 1 -octen-3-ol content of mushrooms decreased during postharvest storage. Use of nutrient supplementation also affected color and maturity of mush? rooms during storage.