Physicochemical characteristics of phytonutrient retained red palm olein and butter-fat blends and its utilization for formulating chocolate spread.

Phytonutrients retained palm olein (PRPOL) was prepared and blended into butterfat at different ratios. The physicochemical characteristics and the phytonutrient composition of blends, as well as its utilization in the preparation of functional chocolate spread were evaluated. The results showed that the redness, yellowness, slip melting point, free fatty acids, peroxide value, iodine value, unsaponifiable matter, diacylglycerol and monoacylglycerol increased while lightness, saponification value, and triacylglycerol significantly decreased upon incorporation of increased quantities of PRPOL into butterfat. The incorporation affected short chain, medium chain and long chain fatty acids content along with variation in the palmitic, stearic, oleic acids content of the blends as compared to butterfat alone. Improvement in carotenoids (6-27 fold), phytotosterols (3-15 fold), tocopherols and tocotrienols (4-17 fold), and squalene (1-6 fold) in blends was observed upon incorporation of PRPOL. Cholesterol level in the blends was reduced (10-50 %) as compared to the butterfat. The blends showed an intermediate solid fat content of PRPOL and butterfat. Moreover, radical scavenging activity of the blends increased with increase in PRPOL quantity. Prepared chocolate spreads showed similar fat, moisture, colour components (L*, a* and b*) and better emulsion stability. The hardness of the spreads was increased upon increasing quantity of PRPOL. The sensory evaluation showed that chocolate prepared by replacing butterfat with 20 % PRPOL had acceptable sensory attributes.

Hypolipidemic mechanism of oryzanol components- ferulic acid and phytosterols.

UNLABELLED: The effect of oryzanol (well known hypolipidemic component in rice bran oil) and its chemical constituents- ferulic acid (FA) and phytosterols on hypolipidemia were investigated. METHODS AND RESULTS: Docking (in silico) studies showed that FA had a better binding ability with lipase while sterols bound well with HMG-CoA reductase. Further in vivo studies of feeding high fat (30%) to rats increased body weights, serum TC, TG, non-HDL-C and reduced HDL-C were observed, compared to normal diet fed group (ND). ORZ treated groups alleviated the lipid profile. Furthermore, increased organ weights, higher intestinal lipase activity, and liver lipid peroxidation was observed in the high-fat group (HF). These effects were ameliorated in oryzanol concentrate fed groups (ORZ). Higher fecal fat was found in ORZ groups, analysis of fecal matter by mass spectroscopy revealed the presence of FA. In vitro, a bile acid binding study supported the strong affinity of sterol towards bile acids. In conclusion, oryzanol in the intestine is cleaved into FA and sterol by intestinal lipase enzymes both lipase and HMG-CoA reductase activities were inhibited, respectively. These hydrolysates eliminated the bile acids, thus lowering lipid profiles.

Physico-chemical characteristics and stability aspects of coconut water and kernel at different stages of maturity.

Coconut water and kernel are the edible portions of the coconut. A study was carried out to evaluate the physico-chemical characteristics, phytonutrients and stability of coconut water (CW), kernel (CK) at different stages of maturity and commercial coconut products (CCP). The moisture content of CW, CK and CCP were in the range of 95-97 g 100 g(-1), 50-85 g 100 g(-1) and 0.4-3 g 100 g(-1) respectively. Fat content in CW was low (4-115 mg 100 g(-1)) whereas in kernel it was high (37-56 g 100 g(-1)). The CW was acidic in nature (pH 4.5-5.2). Ash content of CK decreased with maturity (1.0-1.5 %) whereas that of CW remained steady (0.3-0.4 g 100 g(-1)) with maturity. The total sugar content (3.9-4.6 g 100 g(-1)) and acidity (0.3-0.4 g 100 g(-1)) of CW did not change with maturity. The phenolics content increased in water (1.4-4.3 mg 100 g(-1)) and kernel with maturity (18.5-24.8 mg 100 g(-1)). The fatty acid composition of the oil extracted from the CK had increased saturated fatty acids (C12:0) (38-48 g 100 g(-1)) and decreased monounsaturated fatty acid (C18:1) (13-5 g 100 g(-1)) with maturity. The percentage of medium chain fatty acids increased with different stages of maturity (47-78 g 100 g(-1)). The CW and CK contained higher amount of phenolics (1.4-4.3 mg 100 g(-1) and 18.5-24.8 mg 100 g(-1) respectively) and total tocopherols of CK (0.14-0.59 mg 100 g(-1)) when compared to CCP. This study indicated that CW and CK could serve as valuable raw materials for the preparation of functional food supplement.

Oryzanol as natural antioxidant for improving sunflower oil stability.

Sunflower oil is being made shelf stable by the incorporation of synthetic antioxidants such as tertiary butyl hydroquinone (TBHQ), while natural antioxidants like oryzanol and tocopherols can also be used. The aim of the current investigation was to evaluate the antioxidant effect of natural oryzanol (Oz) concentrate (15.5 % oryzanol) and purified Oz (80 % oryzanol) on oxidative and thermal stability of sunflower oil. Sunflower oil was incorporated with Oz concentrate to provide 0, 0.12, 0.25, 0.50, 0.84, 1.0, 1.60, 2.0, 2.5 and 3.20 % oryzanol in the oil, stored for 5 weeks at 37 °C and oxidative stability was evaluated. It was found that the oryzanol concentrate showed good antioxidant effect with increase in concentration of oryzanol. In another set of experiments, sunflower oil containing purified Oz at 1 % level individually and in combination with 0.1 % α- tocopherol (α-T) was heated at 120 °C for 24 h to evaluate thermal stability. Sunflower oil containing 1 % Oz (80 % purity) showed 98.40 % and sunflower oil containing 1 % Oz and 0.1 % α-T showed 108.75 % antioxidant effect compared to TBHQ taken as 100 %. The study indicated that sunflower oil containing 1 % Oz (80 % purity) and 0.1 % α-T combination provides a synergistic effect in inhibiting primary and secondary products and showed highest thermal stability. SFO containing 1 % Oz added as concentrate also showed good antioxidant effect during storage. Hence, instead of using synthetic antioxidants like TBHQ, we can add natural oryzanol (purified or as concentrate) to sunflower oil to increase its oxidative and thermal stability.

Preparation of food supplements from oilseed cakes.

Oilseed cakes have been in use for feed preparation. Being rich in proteins, antioxidants, fibers, vitamins and minerals, oilseed cakes have been considered ideal for food supplementation. These oilseed cakes can be processed and made more palatable and edible by suitable treatments and then incorporated as food supplements for human consumption. Rice bran pellets (RBP), stabilized rice bran (SRB), coconut cake (CC) and sesame cake (SC) were taken up for the study. These were mixed with distilled water and cooked in such a way to separate the cooked solid residue and liquid extract followed by freeze drying to get two products from each. The raw, cooked dried residue and extract were analyzed for various parameters such as moisture (0.9-27.4 %), fat (2.1-16.1 %), ash (3.3-9.0 %), minerals (2.6-633.2 mg/100 g), total dietary fiber (23.2-58.2 %), crude fiber (2.7-10.5 %), protein (3.2-34.0 %), and the fat further analyzed for fatty acid composition, oryzanol (138-258 mg/100 g) and lignan (99-113 mg/100 g) contents and also evaluated sensory evaluation. Nutritional composition of products as affected by cooking was studied. The cooked products (residue and extract) showed changes in nutrients content and composition from that of the starting cakes and raw materials, but retained more nutrients in cooked residue than in the extract. The sensory evaluation of cooked residue and extract showed overall higher acceptability by the panelists than the starting cakes and raw materials. On the basis of these findings it can be concluded that these cooked residue and extract products are highly valuable for food supplementation than the raw ones.

Retention of natural antioxidants of blends of groundnut and sunflower oils with minor oils during storage and frying.

Unrefined groundnut oil (GNO) and refined sunflower oil (SFO) were blended with four minor oils including laboratory refined red palmolein (RRPO), physically refined rice bran oil (RBO), unrefined sesame oil (SESO), and unrefined coconut oil (CNO) containing natural antioxidants viz., ß-carotene, tocopherols, oryzanol and lignans. The five blends prepared were GNO + RRPO (80:20), GNO + RBO (80:20), GNO + SESO (80:20), SFO + RRPO (50:50) and SFO + CNO (60:40). Prepared blends contained saturated fatty acids (SFA) (16.7-53.3 %); monounsaturated fatty acids (MUFA) (16.0-45.5 %) and polyunsaturated fatty acids (PUFA) (29.2-37.8 %). GNO blends viz., GNO + RRPO, GNO + RBO and GNO + SESO contained ß-carotene (10.7 mg/100 g), oryzanol (0.12 g/100 g) and lignans (0.35 g/100 g) respectively as natural antioxidants. SFO was enriched with ß-carotene (28.7 mg/100 g) and medium chain fatty acids (34.2 %) by blending with RRPO and CNO respectively. The oil blends (200 ml) were packed and stored at 38 °C/90 % relative humidity (RH) and 27 °C/65 % RH and samples were withdrawn at fixed intervals for analysis. Freshly prepared blends were also investigated for their frying performance. During storage, GNO + RBO blend showed highest oxidative stability probably due to the presence of oryzanol in the order GNO + RBO > GNO + SESO > GNO + RRPO. During frying, the peroxide value of GNO blends with RBO (rich in oryzanol) and SESO (rich in lignans) was less while the free fatty acid value was less in SFO blends with RRPO and CNO. Hence, blending of natural antioxidants rich minor oils (RRPO, RBO and SESO) with the major vegetable oils (GNO and SFO) may preserve them by lowering their rate of oxidation during storage and frying.

Omega-3 fatty acids enriched chocolate spreads using soybean and coconut oils.

Chocolate spreads were developed by incorporating two different soybean oil margarines, fat phases prepared using 85 % soybean oil (M1) and 1:1 blend of soybean oil and coconut oil (M2) with commercial palm stearin. Eight formulations were tried by varying skim milk powder (SMP)/fluid skimmed milk (FSM), type of fats (M1, M2, a commercial margarine and a table spread), sugar and cocoa powder and their quality characteristics were compared with a commercial hazelnut cocoa spread. The moisture and fat content were 5-6.1 % and 31.4-32.8 % for formulations with SMP and 21.5-24.7 % and 15.6-21.4 % respectively for those with FSM. Rheological studies of FSM spreads showed higher G″ value (loss modulus) than G' (storage modulus) indicating better spreadability. Descriptive sensory analysis revealed that the products had acceptability score of 8.3 to 10.5 (maximum score: 15). Fat extracted from spreads prepared using M1 and M2 was found to contain 43.9 and 22.3 % linoleic acid and 2.1 and 4.4 % linolenic acid respectively, were free from trans fat while the commercial hazelnut spread had 9.8 % linoleic acid but did not contain linolenic acid. Hence, the developed chocolate spreads have the potential to overcome ω-3 deficiency, ω-6/ω-3 imbalance and to enhance the health standard of people.

Studies on the nutraceuticals composition of wheat derived oils wheat bran oil and wheat germ oil.

Fat-soluble nutraceuticals of cereals are known for number of disease preventive activities. Hence wheat bran oil (WBO) and wheat germ oil (WGO) were extracted from wheat bran and germ which yielded 3.35 % and 7.35 % of oil, containing polyunsaturated fatty acids (PUFA) (64 %, 61.2 %) respectively. Both oils contained tocopherols and carotenoids, which were higher in wheat germ oil (273 mg/100 g, 12.23 mg/100 g) than wheat bran oil (190 mg/100 g, 2.21 mg/100 g). Steryl ferulates were also present in both the oils, but their content was eight-fold higher in WBO than in WGO. Three major steryl ferulates identified by HPLC were campesteryl ferulate and sitostenyl ferulate, campestanyl ferulate and ß-sitosteryl ferulate as in γ-oryzanol and another ferulate, viz., sitostanyl ferulate. A strong IC50 value of 7.5 mg/mL and 21.6 mg/mL DPPH free radicals scavenging for wheat germ oil for wheat bran oil was observed. NMR ((13)C and (1)H) profile explored the evidence of distribution of antioxidant molecules in the unsaponifiable matter of wheat derived oil. Since oils rich in PUFA and minor components are required for the normal physiological activities, blending such oils with other edible oils of the diet in wheat growing countries like India may be useful to provide health benefits.

Stability of oryzanol fortified biscuits on storage.

Biscuit can be used as a functional food to deliver nutraceuticals to consumers. One such natural nutraceutical oryzanol is present in rice bran oil. Oryzanol possesses a variety of health benefits which include reduction of cholesterol in blood, improvement of capillary action of blood vessels, anti-aging effect and others. Biscuit is a well known cereal based processed food and the fortification of oryzanol into the biscuits will go a long way to provide antioxidant rich, highly stable and acceptable functional food to the consumers. Biscuits were prepared with commercially available fat (CF) and oryzanol fortified fat (OFF). The control biscuits (CB) and oryzanol fortified biscuits (OFB) were packed in 200 gauge polypropylene pouches, stored at 27 °C with different relative humidity (RH 11 %, 22 %, 32 %, 44 % and 56 %) and analysed for its stability during storage of 120 days. Critical moisture content of OFB (4.8 %) was slightly less than that of CB (5.3 %). The fat content of the CB (12.2 %) and OFB (12.5 %) did not change during storage while free fatty acid content (0.36 % and 0.60 %) and peroxide value (0.08 and 0.17 meq. O2/100 g biscuit) respectively for CB and OFFB was showed small but significant changes during storage. Oryzanol content (292 mg) and radical scavenging activity (81.1 %) of OFB did not change during storage. The biscuits had a shelf life of minimum 3 months at 27 °C. Oryzanol in OFB showed good stability during baking and storage of biscuits.

Hypolipidemic effect of oryzanol concentrate and low temperature extracted crude rice bran oil in experimental male wistar rats.

Blends of refined groundnut oil (GNO) and oryzanol concentrate having 3, 5, and 10% oryzanol in the blend, and a rice bran oil (RBO) which had retained all the nutrients such as oryzanol, tocopherols and tocotrienols and the unsaponifiable matter components of crude oil (GWF RBO) were prepared. Weanling rats were fed with diet containing the oil blends/rice bran oil at 10% level for 60 days and then dissected. The lipid profiles in serum, liver were investigated and the cholesterol levels were marginally reduced (7-16% in serum, 10-14.5% in liver) in rats fed oryzanol containing diet. RBO, GWF RBO containing diets showed a reduction of serum cholesterol by 14%, 15% respectively when compared to those fed with GNO. Serum and liver lipid analysis also showed significant change in TG concentration in rats fed blended oils containing oryzanol compared to the rats given GNO. Histology of liver and kidneys did not show changes. These studies indicated that oryzanol has an effect in lowering serum and liver cholesterol and shows antiatherogenic properties when incorporated into groundnut oil.

Quality characteristics and stability of Moringa oleifera seed oil of Indian origin.

Cold pressed and hexane extracted moringa seed oils (CPMSO and HEMSO) were evaluated for their physico-chemical and stability characteristics. The iodine value, saponification value and unsaponifiable matter of CPMSO and HEMSO were found to be 67.8 and 68.5 g I2 / 100 g oil, 190.4 and 191.2 mg KOH / g oil and 0.59 and 0.65%, respectively. The total tocopherols of CPMSO and HEMSO were found to be 95.5 and 90.2 mg/Kg. The fatty acid composition of CPMSO and HEMSO showed oleic acid as the major fatty acid (78-79%). The oxidative, thermal and frying stabilities of the CPMSO were compared with commercial raw and refined groundnut oil (GNO and RGNO). The CPMSO was of adequate thermal stability and better oxidative stability as it showed 79% lesser peroxide formation than GNO. The frying stability of CPMSO was better as it showed lower increase in free fatty acid (28%), peroxide value (10 meq O2/Kg) and color (25%) than RGNO (48%, 22 meq O2/kg and 52%, respectively) after frying.

Shelf-life study of Indian traditional food based nutraceutical (oryzanol) enriched instant mixes Bhath-OZ and Upma-OZ.

To provide nutraceutical such as oryzanol through food, two instant mixes based on the Indian traditional food cuisine Bisibele bhath and Upma(Bhath-OZ and Upma-OZ) were developed and evaluated for shelf-life. The formulations contained cereals, pulses, and spices along with oryzanol enriched oil and were packed in 200gauge/50 gauge metallized polyester packaging material and stored under ambient (27 °C 65%RH) and accelerated conditions (37 °C/92%RH). Samples were withdrawn periodically and peroxide value (PV), free fatty acid value (FFA), fatty acid composition, oryzanol, and total tocopherols content were estimated. Sensory evaluation of reconstituted products was also carried out. Oryzanol content (610 and 550 mg%) did not change appreciably in Bhath-OZ and Upma-OZ respectively. The peroxide value under ambient condition increased from 1.1 to 9.3 meq.O2/kg and 2.24 to 9.02 meq.O2/kg during the 6 month storage study at 27 °C and 65% RH, while under accelerated conditions at 37 °C and 92%RH, it increased from 1.12 to 8.54 meq. O2/kg and 2.24 to 6.96 meq. O2/kg during 2 month storage period. Bhath-OZ and Upma-OZ packed in metallized polyester pouches stored at 27 °C and 65% RH had a shelf-life of 4 months without affecting the oryzanol content and quality of instant mixes during the storage period.

Fat-soluble nutraceuticals and their composition in heat-processed wheat germ and wheat bran.

Nutraceuticals availability in heat-processed foods is considered to be the index for healthy food. This study has made an attempt to optimize the temperature to retain nutraceuticals in wheat bran (WB) and wheat germ (WG). Heated WG (130 °C & 140 °C) and WB (140 °C & 150 °C) were analyzed for sensory profiles. Extracted oils were subjected to physicochemical parameter as well as its nutraceuticals. Increased oil yield, color values and reduced free fatty acids were found with varied temperatures. Fat-soluble compounds total tocols, steryl ferulates and carotenoids found in WG (0.316, 0.058 and 0.011%) and WB (0.228, 0.595 and 0.015%) and maximum reductions started in WG (0.183%, 0.034% and 0.004%) at 130 °C. The free radical-scavenging activities of control samples showed high EC50 values than processed samples; however, no differences were observed between two temperatures. Study may clearly spell out that the reduced nutraceuticals observed after subjecting food raw materials to optimum temperature eventually lead to its quality.

Physico-chemical characteristics of defatted rice bran and its utilization in a bakery product.

Defatted rice bran (DRB), a byproduct of rice milling is a rich source of dietary fiber and minerals. In the present study, the physico-chemical characteristics, antioxidant potential of defatted rice bran (Laboratory-LDRB and Commercial -CDRB) and its utilization in preparation of bread were studied. The effect of incorporation of CDRB at varying levels (5, 10 & 15%) on the quality characteristics of bread including physical, rheological and sensory attributes were evaluated and the dietary fiber content and antioxidant activity were determined. The results indicated that LDRB had better nutrient profile, physical and antioxidant properties than CDRB. On the basis of physical characteristics, breads with 5% and 10% CDRB were found to be acceptable as such and those containing 15% were acceptable with addition of bread improvers. The dietary fiber content and total antioxidative activity of bread increased with increasing levels of CDRB, which also improved the shelf life. The results reveal that DRB can be incorporated in breads upto 10% and 15% as such or with bread improvers respectively, as source of fiber and natural antioxidant, as a functional ingredient.

Changes in fatty acids composition during seed growth and physicochemical characteristics of oil extracted from four safflower cultivars.

Fatty acid contents at different stages of maturity and physicochemical characteristics of oil extracted from mature seeds of four safflower cultivars (S208, S400, S541, and S303) were studied. Results indicated that for all cultivars both saturated and unsaturated fatty acid contents fluctuated with seed growth and development. Palmitic acid content decreased up to day 20 after which it started to increase for the S400, S541, and S303 cultivars, while for S208 it progressively decreased. Stearic acid fluctuated with seed growth and development. Oleic acid showed slight changes with seed growth and development, while linoleic acid decreased with seed growth and development for the S400, S541, and S303 cultivars while for S208 after day 30, it started to increase significantly. For all cultivars, glyceride contents varied among the cultivars with maximum values of 97.70, 2.80 and 0.20 for tri-, di- and monoglycerides, respectively. Physicochemical investigation of mature seed oils showed that the color, density, refractive index, free fatty acids, peroxide value, saponification value and unsaponifiable matter were similar for all cultivars while viscosity, iodine value, and acetone insoluble matter varied among the cultivars.

Rapid activation of transducin by mutations distant from the nucleotide-binding site: evidence for a mechanistic model of receptor-catalyzed nucleotide exchange by G proteins.

G proteins act as molecular switches in which information flow depends on whether the bound nucleotide is GDP ("off") or GTP ("on"). We studied the basal and receptor-catalyzed nucleotide exchange rates of site-directed mutants of the alpha subunit of transducin. We identified three amino acid residues (Thr-325, Val-328, and Phe-332) in which mutation resulted in dramatic increases (up to 165-fold) in basal nucleotide exchange rates in addition to enhanced receptor-catalyzed nucleotide exchange rates. These three residues are located on the inward facing surface of the alpha5 helix, which lies between the carboxyl-terminal tail and a loop contacting the nucleotide-binding pocket. Mutation of amino acid residues on the outward facing surface of the same alpha5 helix caused a decrease in receptor-catalyzed nucleotide exchange. We propose that the alpha5 helix comprises a functional microdomain in G proteins that affects basal nucleotide release rates and mediates receptor-catalyzed nucleotide exchange at a distance from the nucleotide-binding pocket.

The function of interdomain interactions in controlling nucleotide exchange rates in transducin.

The intramolecular contacts in heterotrimeric G proteins that determine the rates of basal and receptor-stimulated nucleotide exchange are not fully understood. The alpha subunit of heterotrimeric G proteins consists of two domains: a Ras-like domain with structural homology to the monomeric G protein Ras and a helical domain comprised of six alpha-helices. The bound nucleotide lies in a deep cleft between the two domains. Exchange of the bound nucleotide may involve opening of this cleft. Thus interactions between the domains may affect the rate of nucleotide exchange in G proteins. We have tested this hypothesis in the alpha subunit of the rod cell G protein transducin (Galpha(t)). Site-directed mutations were prepared in a series of residues located at the interdomain interface. The proteins were expressed in vitro in a reticulocyte lysate system. The rates of basal and rhodopsin-catalyzed nucleotide exchange were determined using a trypsin digestion assay specifically adapted for kinetic measurements. Charge-altering substitutions of two residues at the interdomain interface, Lys(273) and Lys(276), increased basal nucleotide exchange rates modestly (5-10-fold). However, we found no evidence that interactions spanning the two domains in Galpha(t) significantly affected either basal or rhodopsin-catalyzed nucleotide exchange rates. These results suggest that opening of the interdomain cleft is not an energetic barrier to nucleotide exchange in Galpha(t). Experiments with Galpha(i1) suggest by comparison that the organization and function of the interdomain region differ among various G protein subtypes.

The amino terminus of the fourth cytoplasmic loop of rhodopsin modulates rhodopsin-transducin interaction.

Rhodopsin is a seven-transmembrane helix receptor that binds and catalytically activates the heterotrimeric G protein transducin (G(t)). This interaction involves the cytoplasmic surface of rhodopsin, which comprises four putative loops and the carboxyl-terminal tail. The fourth loop connects the carboxyl end of transmembrane helix 7 with Cys(322) and Cys(323), which are both modified by membrane-inserted palmitoyl groups. Published data on the roles of the fourth loop in the binding and activation of G(t) are contradictory. Here, we attempt to reconcile these conflicts and define a role for the fourth loop in rhodopsin-G(t) interactions. Fluorescence experiments demonstrated that a synthetic peptide corresponding to the fourth loop of rhodopsin inhibited the activation of G(t) by rhodopsin and interacted directly with the alpha subunit of G(t). A series of rhodopsin mutants was prepared in which portions of the fourth loop were replaced with analogous sequences from the beta(2)-adrenergic receptor or the m1 muscarinic receptor. Chimeric receptors in which residues 310-312 were replaced could not efficiently activate G(t). The defect in G(t) interaction in the fourth loop mutants was not affected by preventing palmitoylation of Cys(322) and Cys(323). We suggest that the amino terminus of the fourth loop interacts directly with G(t), particularly with Galpha(t), and with other regions of the intracellular surface of rhodopsin to support G(t) binding.

Changes in chemical composition, minerals and amino acids during seed growth and development of four safflower cultivars.

Investigation of four safflower (Carthamus tinctorius L.) cultivars (S208, S400, S541 and S303) showed that when the seeds were harvested at different stages of growth and development (10, 20, 30, and 40 days) after flowering, moisture content significantly decreased with time. Oil, protein, ash and crude fiber were increased up to day 30. Thereafter, these parameters started to decline gradually with time. The cultivars differed in their final values; oil content of the seeds varied from 10.90 to 45.40%, moisture varied from 4.20 to 8.10% and from 8.50 to 11.10%, protein from 12.10 to 20.30% and from 13.40 to 29.60%, ash from 2.30 to 5.40% and from 2.80 to 6.50%, for the seeds and defatted meal, respectively. Crude fiber for the defatted meal was found to vary from 29.50 to 38.60%. Carbohydrate for all cultivars decreased rapidly up to day 40 with final values varying from 28.10 to 63.30% and from 56.70 to 70.30% for the seeds and defatted meal, respectively. Mineral content (Cu, Zn, Fe, Mg, Mn) fluctuated while phosphorus content significantly increased with time for all cultivars. Amino acid content of the defatted meal increased with time up to day 30 after which it started to decline gradually for all cultivars.

Taxol-DNA interactions: fluorescence and CD studies of DNA groove binding properties of taxol.

Taxol is perhaps the most successful drug used for the treatment of various cancers. Comprehensive literature accumulated on therapeutics of the drug has indicated numerous side effects. In this paper, by use of fluorescence spectroscopy, it is shown that taxol binds to DNA with an affinity constant (Ka) of 1.08 x 10(7) M-1. This binding is accompanied by a large 'red edge excitation shift' (REES) of fluorescence emission maximum in taxol-DNA complex. The results point to an interaction of taxol with its core eight-membered ring in the DNA groove and the three phenyl rings projecting away from the DNA. The drug encompasses about two base pairs of DNA upon binding to it. Systematic studies with taxol analogues confirms such a mode of binding. These interesting findings on hitherto unknown taxol-DNA interactions may have clinical implications in view of its large number of side effects and pharmacokinetics.