Time series of particulate and dissolved lipid classes during spring phytoplankton blooms in Bedford Basin, a marine inlet

Abstract

The Chromarod-Iatroscan TLC/FID system was used to measure h p~d classes in the dissolved and particulate fractions of seawater samples taken dunng spnng blooms In Bedford Basln, a small inlet in eastern Canada. Polar hpids were the major dissolved lipids present during the bloon~s. Dissolved l i p~d t~m e series indicate decreased phytoplankton exudation and increased bacterial uptake of lipid classes at the t~m e of the chlorophyll maximum. There is evidence to suggest algal uptake of dissolved phospholip~ds. T h~s polar l i p~d class may be used by autotrophs as a source of N and P when inorganic nutrient levels are depleted. The energy-rich storage component, triglyceride, became the major particulate lipid class from the time of the chlorophyll maximum onwards. Other particulate hpid classes present after the chlorophyll maxlmunl suggest that in addition to increased energy storage, there was a greater degree of degradahon of hplds and larger numbers of microheterotrophs.

Seasonal studies of seston lipids in relation to microplankton species composition and scallop growth in South Broad Cove, Newfoundland

“…The lipids were extracted from the suspended particulate matter samples using chloroform-methanol 2 : l (v/v). The lipid classes in the extracts were separated on silica gel coated Chromarod-S111 using 4 different solvent systems and then measured in a n Iatroscan MK V (Parrish 1987). The first solvent system was hexane/diethyl ether/formic acid (99 : 1 : 0.05 by vol.).…”

“…In a comparison between the total triacylglycerol concentration determined by GC on the non-polar column and the total 3000 triacylglycerol concentration determined using the Iatroscan, the 2 totals were corre-2500 lated (r = 0.63, p < 0.02, n = 15) and there was no significant difference between the E means (p = 0.08). However, on average the Zm GC gave a lower total than the Iatroscan, : 151-164, 1995 Scotia from March to August (Parrish 1987, Goutx 1988, Parrish et al 1992b. Total lipid concentrations (Table 1) were 13 to 64 % of the averages of 116 + 27 and 400 * 54 pg 1-' measured in the vicinity of Halifax after the spring bloom (Parrish 1987, Goutx 1988) and 63 to 89% of the total measured in Ship Harbour, a mussel aquaculture site, in August 1989 (Parrish et al 1992b).…”

The place of diatoms in the biofuels industry

“…Crashes can result from a number of factors including nutrient exhaustion, grazing, sedimentation, or viral lysis and remains a fundamentally poorly understood process in all microalgae [36,37]. Environmental studies have shown that once chlorophyll levels begin to decrease (signaling the beginning of the end of the bloom), triacylglycerol (TAG) content increases [38,39]. Translating that into a biofuels production scenario, TAG accumulation precedes cell death and thus crashing would not necessarily be detrimental to production.…”

Dissolved organic matter (DOM) release by phytoplankton in the contemporary and future ocean

“…Parrish (1987) hypothesized that dissolved lipids he measured in Bedford Basin (Canada) were exuded by phytoplankton during the spring bloom. There has been some work on extracellular lipid production by marine diatoms grown in continuous culture (Parrish & Wangersky, 1987;Lombardi & Wangersky, 1991).…”