Cabbage Extract Research Articles

Presence of Antipromotion Factors in Cabbage Extracts

Presence of Antipromotion Factors in Cabbage Extracts

Oviposition stimulants inBarbarea vulgaris forPieris rapae andP. napi oleracea: isolation, identification and differential activity

The closely related butterflies,Pieris rapae andP. napi oleracea, readily laid eggs onBarbarea vulgaris in greenhouse cages. When offered a choice between cabbage andB. vulgaris, P. rapae showed no preference, butP. napi oleracea preferredB. vulgaris. Bioassays of extracts ofB. vulgaris foliage revealed the presence of oviposition deterrent(s) in l-butanol extracts as well as stimulants in the postbutanol water extracts. However, the deterrent effect was apparently outweighed by the strong stimulatory effect in the whole plants. The postbutanol water extract was preferred over an equivalent cabbage extract by both species, but more significantly in the case ofP. napi oleracea. The stimulants were isolated by open column chromatography and HPLC, and the activity was associated with three glucosinolates.P. napi oleracea was more sensitive thanP. rapae to the natural concentration of compounds1 and3, whereas both species were strongly stimulated to oviposit by natural concentrations of compound2. Compounds1 and2 were identified as (2R)-glucobarbarin and (2S)-glucobarbarin, respectively, and3 was identified as glucobrassicin, on the basis of their UV, mass, and NMR spectra. When the pure compounds were tested at the same concentrations applied to bean plants, the (2R)-glucobarbarin at 0.2 mg/plant was preferred over a standard cabbage extract by both butterfly species. However, at a dose of 0.02 mg/plant,P. rapae preferred the cabbage extract whereasP. napi oleracea still preferred the (2R)-glucobarbarin. No such difference in response of the two species to the same two concentrations of (2S)-glucobarbarin was obtained. The results indicate a distinct difference in sensitivity of these butterflies to the epimers of glucobarbarin, and the differences in behavioral responses of the two butterfly species depend to a large extent on the concentration of stimulant present.

Acylated flavonol glycosides from cabbage leaves

Seven flavonol glycosides were isolated from a leaf extract of cabbage and characterized by chemical and spectroscopic methods including 1H and 13C NMR and negative ion FAB-MS. Five compounds were new natural products or were fully characterized for the first time. They are derivatives of kaempferol-3- O-β- d-sophoroside-7- O-β- d-glucoside acylated at C-2‴ with either caffeic acid, p-coumaric acid or ferulic acid, and of quercetin-3- O-β- d-sophoroside-7- O-β- d-glucoside acylated with either caffeic acid or ferulic acid. Kaempferol-3- O-β- d-sophoroside-7- O-β- d-glucoside and kaempferol-3- O-β- d-(2-sinapoylsophoroside)-7- O-β- d-glucoside were found for the first time in cabbage, but they have previously been found in other Brassica species.

Study of natural ascorbigen and related compounds by HPLC

The effect of processing of vegetables on ascorbigen formation, the ultimate fate of its transformation, their pharmacological evaluation are areas requiring detailed study using analytical methods capable of measuring various individual components. A reversed-phase chromatographic system for separation of ascorbigen, which is an indole containing a derivative of l-ascorbic acid, and its synthetic analogs with different substituents in the indole nucleus was developed. The isocratic chromatographic system was also developed for separation of ascorbigen and its transformation products in acidic media. Ascorbigen B which was previously described as the 2-epimer of natural ascorbigen was shown by HPLC to be a mixture of compounds, where natural ascorbigen ‘dimer’ was the major component, and natural ascorbigen and its ‘trimer’ were the minor components. To determine the content of ascorbigen and its transformation products in extracts of fresh or sour cabbage a reversed-phase chromatographic system with gradient elution was developed, with l′-methylascorbigen as an internal standard. Extracts of fresh or sour cabbage contained the ascorbigen (2·4–5·5 mg per 100 g fresh weight), as the major component and ascorbigen ‘dimer’ (0·1–0·3 mg per 100 g fresh weight), ascorbigen ‘trimer’ (0·1–0·3 mg per 100 g fresh weight), 3-hydroxymethylindole (0·2–0·3 mg per 100 g fresh weight) and (indole-3-yl)acetonitrile (0·1–0·5 mg per 100 g fresh weight) as the minor components.

Demonstrations with red cabbage indicator

This paper extends the use of the red cabbage extract into demonstrations that illustrate the acidic or basic nature of solutions of gases and gives suggestions for modifications to project the beautiful range of colors and shades for better viewing in large lecture halls.

Several known indole compounds are not important precursors of direct mutagenic N-nitroso compounds in green cabbage

In this study we investigated the role of indole-3-acetonitrile, indole-3-carbinol, indole and tryptophan in the formation of N-nitroso compounds in green cabbage extracts. Green cabbage extracts were separated by gel permeation chromatography. Fractions were treated with nitrite, tested for mutagenicity and analysed for total N-nitroso. Fractions in which spiked indole-3-acetonitrile, indole-3-carnibol, indole and tryptophan eluted appeared to be low in mutagenic activity and contained relatively small amounts of N-nitroso compounds. To detect indole compounds other than the ones used in the gel permeation chromatography experiments, high-performance liquid chromatography and gas chromatography-mass spectrometry analyses were performed of green cabbage extracts. Indole-3-carboxaldehyde was found to be the most commonly occuring indole compound, but it did not show direct mutagenic activity upon nitrite treatment. Indole-3-acetonitrile was the second most common compound; although it was mutagenic after nitrite treatment, its contribution to the mutagenicity of nitrite-treated green cabbage was roughly estimated to be only 2%. No other indole compounds were detected. From this study we conclude that neither the tested indole compounds nor indole-3-carboxaldehyde play a significant role in the formation of direct mutagenic N-nitroso compounds in nitrate-treated green cabbage extracts.

Oviposition behavior of the cabbage root fly,Delia radicum (L.), influenced by host plant extracts

An ethanolic extract of cabbage leaves (Brassica oleraceavar. capitata,Golden Acre)and derived fractions were tested on natural and surrogate leaves in order to study the oviposition behavior of the cabbage root fly Delia radicum(Diptera: Anthomyiidae). On surrogate plastic leaves coated with a thin layer of paraffin wax and treated with 0.1 gram leaf equivalent (gle) of an ethanolic raw cabbage extract, the females displayed the same sequence of behavioral patterns as on a natural host plant. The quantified oviposition behavior correlated well with the actual number of eggs laid. The extract-treated surrogate leaves received at least as many eggs as natural leaves with a similar surface area. Previous exposure to surrogate or natural leaves seemed not to induce a specific preference. The three fractions (hexane, butanol, and water) of the raw extract stimulated the oviposition behavior. This was taken as evidence for the presence of a multicomponent mixture or a “chemical pattern” in the cabbage leaves stimulating oviposition. At the tested concentration each fraction alone could stimulate in some individuals the complete behavior. No effect of volatile components of the raw extract could be detected. This is thought to be due to the extraction procedure, which limits the production of attractive, volatile compounds, such as isothiocyanates.

Inhibition by selected food components of human and porcine intestinal pteroylpolyglutamate hydrolase activity

Studies were conducted to determine the in vitro effect of selected food components on activity of the brush border membrane pteroylpolyglutamate hydrolase (folate conjugase) of porcine and human intestine. Foods differed widely in their effects although the pattern of the effects on both porcine and human enzymes was similar. Extracts of legumes, tomatoes, and orange juice consistently inhibited the conjugase activity. Citrate was also inhibitory to some extent. In contrast, extracts of cereal grain flours, whole egg, milk, cabbage, cauliflower, and lettuce caused little inhibition. Purified phytohemagglutinins, soybean trypsin inhibitors, and bovine milk folate-binding protein had no effect on the conjugase activity at the concentrations tested. The food substances that inhibited the conjugase activity did not bind the polyglutamyl folate substrate or inhibit intestinal brush border membrane sucrase and alkaline phosphatase. These findings suggest that food composition may influence folate bioavailability by interfering with the intestinal deconjugation of dietary polyglutamyl folates.

Heat stability of superoxide dismutase in cabbage

The occurrence of superoxide dismutase activity (SOD) in extracts of cabbage ( Brassica oleracea var. capitata) was detected by use of the nitroblue tetrazolium assay method for the measurement of superoxide anion (O − 2 ). The SOD activity found in aqueous extracts of cabbage was destroyed at temperatures greater than 45°C, whereas, for commercial preparations of bovine SOD, temperatures in excess of 65°C were required for deactivation of the enzyme. Heat inactivation energies have been calculated. Tests for sensitivity to cyanide have indicated that a substantial proportion of the cabbage SOD activity is due to the CuZn type of enzyme. As shown by isoelectric focusing, three SOD isoenzymes were present in the aqueous extracts of cabbage.

The heat stability of purified spring cabbage peroxidase isoenzymes

Two peroxidase isoenzymes, purified from extracts of Spring cabbage, have been shown to possess different heat-stabilities. The anionic isoenzyme had an isoelectric point of 3·7 and was relatively heat stable, while the cationic isoenzyme, pI 9·9, was more readily inactivated by heat. Neither isoenzyme showed regeneration of peroxidase activity following heat inactivation.

Dipeptidyl tetrapeptide hydrolase, a new enzyme with dipeptidyl ligase activity

Dipeptidyl tetrapeptide hydrolase, a new enzyme with dipeptidyl ligase activity, partially purified from cabbage (Brassica oleracea) extract by means of ammonium sulfate fractionation and DEAE-Sephadex A-25 column chromatography, was shown to catalyze the syntheses of Ala-Gly-Ala-Gly, Ala-Ala-Ala-Ala, and Gly-Ala-Gly-Ala from Ala-Gly, Ala-Ala, and Gly-Ala, respectively, by a direct condensation mechanism without prior activation of the carboxyl group of one molecule of substrate coupled to an energy-yielding reaction. The enzyme has a pH optimum of 7.2, a strict requirement for a reduced sulfhydryl group for catalytic activity, and a substrate specificity for a dipeptide with either two Ala residues or one Ala and one Gly residue. The enzyme substrate-binding site is estimated to be about 15 Å (1 Å = 0.1 nm) long with four subsites, each of which recognizes Ala. Only substrates with the L-isomer of Ala and with an amino group in the alpha position are active. The energy gained in the synthesis of the internal peptide bond as estimated from the equilibrium constant for the synthesis of Ala-Gly-Ala-Gly from Ala-Gly is 1861 cal (1 cal = 4.1868 J). This energy requirement is 2269 cal lower than the energy required to synthesize the peptide bond in DL-Ala-Gly from DL-Ala and Gly. When the purified enzymatically synthesized tetrapeptide product was incubated with the enzyme, it was hydrolyzed to Ala-Gly.

Chemical Recognition of Host Plants for Oviposition by the Cabbage Butterfly, Pieris rapae (Lepidoptera: Pieridae)

A bioassay using green index cards demonstrated the stimulatory effect of cabbage extracts on oviposition by Pieris rapae . The chemicals involved are water soluble, and the butterflies readily differentiated between different concentrations. High concentrations of the glucosinolate sinigrin also stimulated oviposition but had little effect on the spatial distribution of eggs over treated and control areas of cards. Response to cabbage extracts, however, resulted in precise discrimination between treated and control areas throughout the active life of the butterflies. Cabbage volatiles did not enhance stimulation of oviposition on extract-treated cards. The results suggest that more than one nonvolatile chemical is needed for both stimulation of oviposition and selection of the exact oviposition site

Effect of Common Vegetables on Thyroid Function in Rats-A Preliminary Study

Goitrogenic potency of some vegetables of Delhi were studied in rats. Adult male rats were fed separately on thiouracil, thiocyanate and extracts of carrot, cabbage and turnip procured from Delhi market for 26 days. Cabbage and turnip showed high thiocyanate contents while carrot did not show any measurable amount. Appreciable increase in thyroid weight to body weight ratio, plasma thiocyanate, plasma/sup 131/1 contents and protein bound/sup 131/ 1 or plasma were observed in all groups of experimental, rats, except carrot. Results indicated goitrogenic nature of cabbage and turnip in rats.

Deodorization of a Colorant Prepared from Red Cabbage

ABSTRACTA process for preparing odor‐free colorant from red cabbage was developed. Anthocyanins in an acidified aqueous cabbage extract were adsorbed on Amberlite XAD‐7, water‐washed to remove residual cabbage odor, eluted with ethanol containing 0.1% HCl, and concentrated by evaporation. Optimal conditions for single stage batch contact and column deodorization were determined. Pigment recovery generally exceeded 90%. The stability, spectral, and colorant properties of the recovered pigments were not altered significantly by the process. Spent adsorbent could be regenerated by water washing without adversely affecting process efficiency or colorant performance.

Inducible Cadmium Binding Complexes of Cabbage and Tobacco

Cadmium complexes with apparent molecular weights of 10,000 were observed in aqueous extracts of Cd-treated cabbage (Brassica capitata L., cv. red danish) and tobacco (hybrid of Nicotiana glauca and N. langsdorffii) plants. The amount of complex (as Cd) recovered was found to be dependent on the concentration of the metal in the growth medium and the total time of exposure of plants to the metal. Induction of the complex at moderate levels of (112)Cd exposure was monitored after labeling the complex with (109)Cd in vitro. The constitutive nature of the ligand of the complex in cabbage and tobacco leaves was suggested when control plant extracts were exposed to (109)Cd. Such extracts contained (109)Cd, which eluted from Sephadex G-50 in the region of Cd complex. Simultaneous labeling with (112)Cd and (35)S or (32)P indicated that the complex contained sulfur but probably not phosphorus. The amount of (35)S which eluted coincident with (112)Cd complex increased during complex induction. No evidence was found for the presence of 10,000 molecular weight Cd complex in stem exudates (vascular sap) of Cd-treated plants.The results obtained are consistent with the presence in these tissues of a ligand which is both inducible and constitutive and binds Cd in mercaptide bonds. All of these properties, and others reported earlier, are characteristic of Cd-metallothionein formed in animals.

Purification and properties of a plant desmutagenic factor for the mutagenic principle of tryptophan pyrolysate.

A desmutagenic factor for Trp-P-2 which is a potent mutagen discovered by Sugimura and his colleagues in pyrolysis products of tryptophan has been identified from extracts of cabbage (Bvassica oleracea) leaves. Analysis of this factor to determine its composition revealed that it had a molecular weight of 43, 000 and contained 45.2 μg of sugar per mgof protein. The purified factor exhibited a hemo-protein-like absorption spectrum with a Soret band of 404 nm and α and β bands at 640 and 497 nm, respectively. In addition to counteracting the mutagenicity of Trp-P-2, the mutagenic activity of Trp-P-1, which is 4-methyl derivative of Trp-P-2, was equally abolished by the factor. Other mutagens, such as ethidium bromide and 2-aminoanthracene, were found to be susceptible to the factor, but it had no effect on such mutagens as ICR-170 and AF-2. Furthermore, the factor greatly enhanced the mutagenicity of 1, 2-diamino-4-nitrobenzene. Several lines of investigations were pursued to determine the possible mode of action to explain the results obtained with the factor. These studies indicated that the factor was a peroxidase which possessed NADPH-oxidaseactivity. In this paper, the mechanism of the desmutagenic action of the factor is discussed with special reference to these enzymatic activities.

Functional Properties of a Food Colorant Prepared from Red Cabbage

ABSTRACTSpectral, colorant, and stability properties of colorants based on red cabbage, grape, cranberry, beet, and Red No. 40 were compared in buffer and in a simulated beverage. At pH 3, red cabbage imparted a red color similar to that of beet juice and less orange than that of the other colorants. Increasing the pH of red cabbage extracts to 4 produced a bathochromic shift and decreased color strength. Tristimulus parameters displayed maxima when L was varied. Red cabbage pigments were more stable during heating and storage than were the other colorants tested. pH had little effect on color stability; exposure to light greatly increased color loss during storage.

Binding Specificity and Possible Analytical Applications of the Cytokinin-binding Antibody, Anti-N6-Benzyladenosine

Antibodies elicited in rabbits by immunization with an N(6)-benzyladenosine-bovine serum albumin conjugate bound N(6)-benzyladenosine specifically. The affinity constants and specific binding site concentrations for a number of cytokinins and related compounds were estimated by nonlinear least squares analysis of direct or competitive ultrafiltration data. The antisera contained 230 to 330 nanomoles of cytokinin binding sites per gram protein. Affinity constants were 8.8 x 10(8) molar(-1) for 6-benzylaminopurine, 8.4 x 10(7) molar(-1) for kinetin, 9.1 x 10(7) molar(-1) for 6-(3-methyl-2-butenylamino)purine, 6.6 x 10(6) molar(-1) for 6-(4-hydroxy-3-methyl-trans-2-butenylamino)purine, and 2.0 x 10(4) molar(-1) for 6-methylaminopurine. Affinity constants were below the limit of detectability (<10(4) molar(-1)) for benzylamine, adenine, and other adenine derivatives without an N(6)-side chain. The N(6)-substituent was thus immunodominant, but the purine moiety was also necessary for binding affinity. The antibodies were immobilized on cyanogen bromide-activated Sepharose with 95% retention of binding capacity and without apparent change in affinity constants. Columns of the immobilized antibody retained 64% of the [(3)H]6-(3-methyl-2-butenylam-ino)purine from 2 nanomolar solutions and readily trapped [(14)C]6-benzylaminopurine that had been added to crude extracts of cabbage. Aqueous 10% pyridine adjusted to pH 7.3 with formic acid effectively eluted bound cytokinins from gel columns without loss of binding capacity of the immobilized antibody.

A Simple, Inexpensive, High Pressure Liquid Chromatographic Method for Separating Cytokinins in Plant Extracts

Separation of a mixture of the main cytokinins occurring naturally in plant tissues was achieved by high pressure liquid chromatography using insoluble polyvinylpyrrolidone as the solid support. The separation of each cytokinin was first assessed over a range of salt and l-butanol concentrations and pH using a mixture of borate buffer and l-butanol as the mobile phase to determine the conditions necessary for optimum resolution. A discrete separation of zeatin, N-6-(Delta-2-isopentenyl)adenine, their related ribonucleosides, and kinetin was achieved using a simple isocratic elution with 0.025 m borate buffer at pH 6.8 and 4% (v/v) l-butanol. A number of cytokinin-active compounds were detected in cabbage extracts by the Amaranthus betacyanin bioassay using this separation technique.

A Clean-up Method for the Detection of Carbamate Insecticides in Foods by Thin-Layer Chromatography

A clean-up method suitable for the detection of carbamate insecticides in unpolished rice, green tea, cabbage, and spinach by thin-layer chromatography was developed. The clean-up method consists of the treatment of food extracts with a coagulating solution, followed by washing with an alkaline solution. Washing with sodium benzoate solution is effective for removing most of caffeine in the extract of green tea. Washing with an acidic solution is necessary for the removal of contaminants in the extracts of cabbage and spinach. By this method, carbaryl (0.1 ppm) added to the food was finally recovered in an ethanolic solution (100 μl), and the detection limit on thin-layer plates was 4-5 μl. The detection of Suncide, Meobal, and Osbac from the food fortified at 1 ppm each was successful by the application of 3-7 μl of the finally obtained solution to thin-layer chromatography.