Crude extract

The majority of promising drug candidates emerging from marine natural products research to date are potential cancer treatments. Six anti-cancer compounds that are either marine natural products or synthetic analogs of marine natural products have made it to clinical trials. The first of these compounds to enter clinical trials was didemnin B (43), one of a family of cyclic depsipetides isolated from the Caribbean tunicate Trididemnum solidum Didemnin B was advanced to Phase II clinical trials for treatment of small cell lung cancer, myeloma, prostate cancer, and melanoma. Unfortunately, no favorable responses were found so the compound has been withdrawn. Crude extracts of another Caribbean tunicate, Ecteinascidia turbinata, showed extremely... 

Most purification procedures for a particular protein are developed in an empirical manner, the overriding principle being purification of the protein to a homogeneous state with acceptable yield. Table 5.5 presents a summary of a purification scheme for a selected protein. Note that the specific activity of the protein (the enzyme xanthine dehydrogenase) in the immuno-affinity purified fraction (fraction 5) has been increased 152/0.108, or 1407 times the specific activity in the crude extract (fraction 1). Thus, xanthine dehydrogenase in fraction 5 versus fraction 1 is enriched more than 1400-fold by the purification procedure. 

It was known for some time that even after the corticoids had been separated from crude extracts of the adrenal cortex, the remaining material, the so-called "amorphous fraction" still possessed considerable mineralocorticoid activity. Aldosterone (250), one of the last steroids to be isolated from this fraction, proved to be the active principle. This compound proved to be an extremely potent agent for the retention of salt, and thus water, in body fluids. An antagonist would be expected to act as a diuretic in those edematous states caused by excess sodium retention. Although aldosterone has been prepared by both total and partial synthesis, the complexity of the molecule discouraged attempts to prepare antagonists based directly on the parent compound. 

Cannabinoids were used in medicine in the form of their crude extracts many centuries ago. Lately the use of cannabis for so-called recreational purposes has become a national vice of substantial proportions. Several attempts have been made to focus the potentially useful pharmacological properties of marijuana into drug molecules with no abuse potential. 

For centuries, the beneficial effects of crude extracts from the ginkgo tree were well known in China and India. In traditional Chinese medicine, a boiled-down extract of ginkgo leaves is inhaled to alleviate asthmatic symptoms, and, in India, ginkgo extracts constitute a key ingredient of Soma, a mystical liquid that is thought to increase life span.5 The Japanese know it as the Itcho tree and they frequently use its edible fruit, the ginkgo nut, in cooking. 

Fig. 6.3.4 Luminescence spectrum of the Watasenia bioluminescence reaction measured with a crude extract of light organs that contain particulate matters, in chilled 0.1 M Tris-HCl buffer, pH 8.26, containing 1.5 mM ATP. From Tsuji, 2002, with permission from Elsevier.

Luminescence reaction. In air, partially purified preparations of the photoprotein emit light in the presence of Fe2+ and a peroxide however, highly purified preparations require two additional substances, cofactors 1 and 2, to emit the same intensity of light. Both cofactors can be substituted with a small amount of a crude extract of the photoprotein. 

Fig. 8.2 Gel filtration on a column of Sephadex G-100 at pH 8 (both panels) of the crude extract of Gonyaulax polyedra cells prepared at pH 8 (upper panel) and prepared at pH 6 (lower panel). The activities of the 35 kDa and 130 kDa luciferases are measured by the addition of an excess of luciferin at pH 6.3 ( ) or at pH 8(A). The activity of the luciferin-bound LBP (luciferin-binding protein) in the upper panel is measured after the addition of an excess of 35 kDa luciferase at pH 6.3 ( ). In the lower panel, the LBP activity can be obtained by the addition of an excess of luciferin at pH 8, followed by the removal of unbound luciferin with a small column of Sephadex G-25 before the luminescence assay of bound luciferin at pH 6.3 (see the Section 8.2.8). The Overlap in the upper panel is the light emission resulting from the mixing of an aliquot of the fractions with pH 6.3 buffer. From Fogel and Hastings, 1971, with permission from Elsevier.

Chemiluminescent compounds and their precursors in P. stipticus. Although P. stipticus is negative in the luciferin-luciferase reaction, crude extracts of this fungus are chemiluminescent, like the luciferin obtained from Ompbalia flavida by Kuwabara and Wassink (1966). The chemiluminescence is elicited by the addition of H2O2 and Fe2+ under a mild condition of pH 5-8, and the luminescence is strongly... 

Cormier and Dure (1963) found another type of luciferin and called it protein-free luciferin. Protein-free luciferin was found in the vapor condensate of freeze-drying whole animals, and also in the 3 5-56 % ammonium sulfate fraction of the crude extract noted above. The protein-free luciferin behaved like an aromatic or heterocyclic compound and it was strongly adsorbed onto Sephadex and other chromatography media, requiring a considerable amount of solvent to elute it. The luminescence reaction of protein-free luciferin in the presence of luciferase required a 500-times higher concentration of H2O2 compared with the standard luciferin preparation. Both types of the luciferin preparation had a strong odor of iodoform. 

Cypridina luciferase is not available commercially at present. However, Cypridina luciferase can be readily extracted from both live and dried Cypridina, and the crude extract, after dialysis, can be used in the measurement of Cypridina luciferin. Live Cypridina can be collected in Japan, and the ostracod can be cultivated in laboratory (see the last part of Section 3.1.2). Dried Cypridina is available from certain sources, including the author s laboratory. 

Watanabe, H., et al. (1991). Aldehyde-enhanced photon emission from crude extracts of soybean seedlings. In Stanley, P. E., and Kricka, L. J. (eds.), Biolumin. Chemilumin., Proc. Int. Symp., 6th 1990, pp. 273-276. Wiley, Chichester, UK. 

Owing to the weak hydrophobicity of the PEO stationary phases and reversibility of the protein adsorption, some advantages of these columns could be expected for the isolation of labile and high-molecular weight biopolymers. Miller et al. [61] found that labile mitochondrial matrix enzymes — ornitine trans-carbomoylase and carbomoyl phosphate synthetase (M = 165 kDa) could be efficiently isolated by means of hydrophobic interaction chromatography from the crude extract. 

Crude extract Unbound with chitin fraction Binding with chitin fraction ... 

We found that the PO activity in all the plants tested increased in the presence of chitin as compared with the activity in crude extracts. This activation was not only found in chitin-eluted fraction but also in that fraction not adsorbed on chitin. This data confirms the... 

Synthetic hCT Is not commercially available now. Most assays have been developed by using hormone supplied as gifts from the CIBA-Gelgy Co., Basel, Switzerland for 131i or labeling. Immunization and standards although several useful antisera have been produced by Immunization with crude extracts of medullary carcinoma tissue. 

Stabilization of crude and purified anthocyanin extracts from agai by the addition of tannic acid resulted in a 65% half-life increase of anthocyanins from the crude extract and 610% of the half-life of the purified one. Although tannic acid was considered an efficient copigment,in general all cinnamic acids give unpleasant odors and tastes to solutions. 

The same resin was used for the purification via downstream processing of carminic acid, the natural colorant extracted from cochineal. By a direct adsorption method, a crude extract was applied on the polymeric bed gel and the adsorption kinetics studied using elution with hydrochloric acid and ethanol. The desorbed pure carminic acid concentrated under vacuum yielded a final product that complied with Codex Alimentarius requirements and FAO/OMS norms. 

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