EFFECTS OF HIGH AND LOW TEMPERATURES ON THE LIPID CONTENT OF THE DIGESTIVE GLAND-GONAD COMPLEX OF BIOMPHALARIA GLABRATA AS DETERMINED BY HIGH PERFORMANCE THIN LAYER CHROMATOGRAPHY

Abstract

High performance thin-layer chromatography (HPTLC) was used to study the effects of both high and low temperatures on the neutral and polar lipid content of the digestive gland-gonad complex (DGG) of Biomphalaria glabrata snails. The low temperature experiments were performed at −10°C, 6°C, 14°C, and ambient (22–24°C) temperatures. The high temperature experiments were performed at ambient (22–24°C), 28°C, and 32°C. Snails were maintained at these temperatures for various periods of time and then their DGGs were examined by HPTLC methods to determine changes that occurred in the lipid content as a function of temperature. In the low temperature experiment, after 30 min, the snails maintained at ambient temperature had significantly greater amounts of phosphatidylcholine and phosphatidylethanolamine than those maintained at cold temperatures. These findings suggest that cold temperatures had a detrimental effect on the structural lipids of the snails. In the high temperature study, at 4 weeks after the initiation of the experiment, snails maintained at the ambient temperatures had significantly greater amounts of free sterols than those maintained at the higher temperatures. These findings suggest that high temperatures had a deleterious effect on the lipid metabolism of the snails.

Keywords:

• Biomphalaria glabrata
• densitometry
• high-performance thin-layer chromatography
• high temperature
• HPTLC
• low temperature
• neutral lipids
• polar lipids

Notes

^a Culture A was maintained at ambient temperature (22–24°C); Culture B, 14°C; Culture C, 6°C; Culture D, −10°C.

^b The phosphatidylcholine content of culture A was significantly greater than that of the other experimental groups.

^c The phosphatidylethanolamine content of culture A was significantly greater than that of the other experimental groups.

^d There were no samples for the −10°C; snails in these cultures had died.

^a Culture A was maintained at ambient temperature (22–24°C); Culture B, 14°C; Culture C, 6°C; Culture D, −10°C.

^a Culture A was maintained at ambient temperature (22–24°C); Culture B, 14°C; Culture C, 6°C; Culture D, −10°C.

^b The free sterol content of culture A was significantly greater than that of the other experimental groups.

^c The free fatty acid content of culture A was significantly greater than that of the other experimental groups.

^d The phosphatidylcholine content of culture A was significantly greater than that of the other experimental groups.

^e The phosphatidylethanolamine content of culture A was significantly greater than that of the other experimental groups.

^f There were no samples for the −10°C, snails in these cultures had died.

^a Culture A was maintained at ambient temperature (22–24°C); Culture B, 14°C; Culture C, 6°C; Culture D, −10°C.

^b There were no samples for the −10°C, snails in these cultures had died.

^c There were no samples for the −10°C, snails in these cultures had died.

^a Culture E was maintained at ambient temperature (22–24°C); Culture F, high (28°C); Culture G, very high (32–34°C).

^b The free sterol content of culture E snails was significantly greater than that of the other experimental groups.