Growth and Motility of the Diatom Cylindrotheca Closterium: Implications for Commercial Applications
Year: 2009
Type: other
Abstract: A unialgal isolate of Cylindrotheca closterium (Ehremberg) Lewin and Reimann from the Newport River estuary was grown in f/2 seawater media under continuous saturating irradiance at 27uC.Growth rates and motility were measured in four replicate flasks under two experimental growth conditions: 1) unstirred batch cultures shaken once per day to suspend the cells and break down density gradients within the flasks, and 2) continuously stirred batch cultures on an orbital shaker (160 rpm).Cell densities were measured daily for six days by counting a minimum of 1,000 cells from each of four replicate culture flasks using a Neubauer hemacytometer.Daily measurements of motility were made by noting the percentage of cells moving within a 0.04 mm 2 area of the hemacytometer over a 10 sec interval.Both treatments showed similar logarithmic growth during the first three days but equilibrium cell density was twice as great in the unstirred treatment by day six.Growth rates on day one in both experimental conditions exceeded 2.3 divisions per day.Initial high motility rates ($95%) were maintained until day three in the unstirred treatment but dropped in half by day two in the continuously stirred treatment.A significant negative correlation existed between culture age and motility in both treatments.These findings have implications for growing C. closterium in industrial applications including use as a settlement agent and feed in abalone hatcheries, bioassay for the detection of heavy metals in surface sediments, and remediation tool to remove nutrients from aquaculture effluents.
Author: Michael B. Kingston
Language: English
Topic: Diatoms and Algae Research
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2188824096