In 1826, a storm caused a rock slide at Crawford Notch that killed an entire family of nine and brought national attention to the notch. The tragedy and the idyllic beauty of the surrounding area may have inspired Cole to paint this landscape. Cole, who subscribed to the romantic notion that unspoiled nature is a reflection of God’s presence and that the destruction of virgin forests is an outrageous violation of His will, has included elements in this painting that hint at his message: serene, breathtaking beauty of the area, human activity that is beginning to spoil this beauty, and gathering storm clouds that foreshadow the impending catastrophe.
Sigma β-Glucuronidases are routinely used for the enzymatic hydrolysis of glucuronides from urine1,2, plasma3,4, and other fluids5 prior to analysis by enzyme immunoassay, mass spectrometry, gas chromatography, high performance liquid chromatography, or other means. Typically, between 1 and 20 units of glucuronidase is used per μl of plasma, urine, or bile for the enzymatic hydrolysis of glucuronides present in these samples.1–5 The exact amount needed will depend on the specific conditions used and must be determined empirically.
The enzyme from Patella vulgata is reported to be much more effective in hydrolyzing opiod-glucuronides.6,7 Whereas the Helix pomatia and E. coli enzymes are reported to be slightly more effective in hydrolyzing steroid-glucuronides.8
One Sigma or modified "Fishman" unit will liberate 1.0 μg of phenolphthalein from phenolphthalein glucuronide per hr at 37 °C at pH 5.0 (pH 6.8 for the E. coli source) (30 min assay).
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