Retort process modelling for Indian traditional foods.

Indian traditional staple and snack food is typically a heterogeneous recipe that incorporates varieties of vegetables, lentils and other ingredients. Modelling the retorting process of multilayer pouch packed Indian food was achieved using lumped-parameter approach. A unified model is proposed to estimate cold point temperature. Initial process conditions, retort temperature and % solid content were the significantly affecting independent variables. A model was developed using combination of vegetable solids and water, which was then validated using four traditional Indian vegetarian products: Pulav (steamed rice with vegetables), Sambar (south Indian style curry containing mixed vegetables and lentils), Gajar Halawa (carrot based sweet product) and Upama (wheat based snack product). The predicted and experimental values of temperature profile matched with ±10 % error which is a good match considering the food was a multi component system. Thus the model will be useful as a tool to reduce number of trials required to optimize retorting of various Indian traditional vegetarian foods.

Modeling of chromium (VI) biosorption by immobilized Spirulina platensis in packed column.

This study describes biosorption of chromium (VI) by immobilized Spirulina platensis, in calcium alginate beads. Three aspects viz. optimization of bead parameters, equilibrium conditions and packed column operation were studied and subsequently modeled. Under optimized bead diameter (2.6mm), calcium alginate concentration (2%, w/v) and biomass loading (2.6%, w/v) maximum biosorption was achieved. 140 g l(-1) loading of optimized beads resulted in 99% adsorption of chromium (VI) ions from an aqueous solution containing 100 mg l(-1) of chromium (VI). The quantitative chromium (VI) uptake was effectively described by Freundlich adsorption isotherm. The immobilized S. platensis beads were further used in a packed bed column wherein the effects of bed height, feed flow rate, inlet chromium (VI) ion concentration were studied by assessing breakthrough time. The performance data were tested for various models fitting in order to predict scale up-design parameters such as breakthrough time and column height. Results were encouraging.

Kinetic and equilibrium modeling of chromium (VI) biosorption on fresh and spent Spirulina platensis/Chlorella vulgaris biomass.

Biosorption of chromium (VI) was studied using both fresh and spent algal biomass of Spirulina platensis and Chlorella vulgaris. Both showed comparable behavior suggesting that biosorption is primarily a surface phenomenon. Biosorption rate was very fast during the first five minutes, in which almost 50% of the chromium (VI) was adsorbed. Two step kinetic model was proposed for biosorption. Equilibrium data obeyed Freundlich and Langmuir adsorption isotherms. Fresh algal biomass of S. platensis gave maximum of 73.6% biosorption of chromium (VI) in 100 ppm solution at 1 g l(-1) cell loading. For improved economics, beta-carotene was extracted from S. platensis and the spent biomass was used for chromium (VI) biosorption. The maximum biosorption by spent biomass was increased to 86.2%. Thus, this two step process not only showed improved efficiency in biosorption ( approximately 17% increase) but also gave valuable byproduct, namely beta-carotene.

Efficacy of potassium and magnesium in essential hypertension: a double-blind, placebo controlled, crossover study.

OBJECTIVE: To evaluate the antihypertensive activity of potassium given alone or in combination with magnesium in patients with mild hypertension. DESIGN: A double blind, randomised, placebo controlled, crossover trial of 32 weeks' duration. SETTINGS: Cardiology outpatient department, Sassoon General Hospitals, Pune, India. PATIENTS: 37 Adults with mild hypertension (diastolic blood pressure less than 110 mm Hg). INTERVENTION: Patients received either placebo or potassium 60 mmol/day alone or in combination with magnesium 20 mmol/day in a crossover design. No other drug treatment was allowed. MEASUREMENTS: Blood pressure and heart rate assessed at weekly intervals and biochemical parameters at monthly intervals. RESULTS: Potassium alone or in combination with magnesium produced a significant reduction in systolic and diastolic blood pressures (p less than 0.001) and a significant reduction in serum cholesterol concentration (p less than 0.05); other biochemical variables did not change. Magnesium did not have an additional effect. Urinary potassium excretion increased significantly in the groups who received potassium alone or in combination with magnesium. The drug was well tolerated and compliance was satisfactory. CONCLUSION: Potassium 60 mmol/day lowers arterial blood pressure in patients with mild hypertension. Giving magnesium as well has no added advantage.

Evaluation of the mutagenicity of 'pan masala', a chewing substitute widely used in India.

Mutagenicity of polar and non-polar extracts of a popular brand of 'pan masala' was examined using the Salmonella/mammalian microsome test (Ames assay) and 2 tester strains of Salmonella typhimurium, TA98 and TA100. These extracts were also subjected to pretreatment with sodium nitrite at acidic pH, to simulate conditions for endogenous nitrosation. The aqueous, aqueous:ethanolic and chloroform extracts as well as their nitrosated mixtures were non-mutagenic in the Ames assay, in the presence and absence of metabolic activation. Only the ethanolic extract elicited a weak mutagenic response in strain TA98 without metabolic activation demonstrating the presence of direct-acting frameshift mutagens in 'pan masala'.

Effects of cimetidine combination with cyclophosphamide in transplanted murine tumors.

Studies were carried out on the combination of Cimetidine (CMTD) with Cytoxan (CTX) in three murine tumors. While the combination significantly potentiated the anticancer effect of CTX in L1210 leukemia, the results with P388 leukemia were not significantly different. The results with Lewis Lung Carcinoma showed a consistent reduction in the number of metastases. However, there was no consistent concomitant prolongation in survival. The host strain, biology of the tumour and the drug used in combination with CMTD might be some of the factors responsible for the varied response.

Pharmacokinetics of methotrexate in Indian children and its relationship to nutritional status.

Any significant change in the pharmacokinetics of an anticancer drug would have a bearing on its therapeutic efficacy and toxicity. Nutritional deficiencies have been shown to affect the pharmacokinetics of a drug. Since malnutrition and undernutrition are widely prevalent in India, the effect of initial nutritional status on the overall kinetics of methotrexate (MTX) administered to cancer patients appeared to be of practical importance. A study of 6 Indian children with malignancies was made to examine the pharmacokinetics of low dose MTX and its relationship to the nutritional status. The results indicate that the relative weight correlates well with the anthropometric parameters, nutritional parameters and dietary intake and may be used as a marker of nutritional status.

Anticancer activity of new 3-amino-pyrrolidinedione-nitrogen mustard derivatives on murine sarcoma 180.

A 2,5-pyrrolidinedione linked nitrogen mustard derivative, (R,S)3-[N,N-bis(2-chloroethyl)]-amino-1-(2'-methoxyphenyl)pyrrolidine- 2,5-dione hydrochloride (I) showed a marked antiproliferative effect on mouse Sarcoma 180. Since (I) is also active against L1210 and P388 leukaemias, its toxicity in mice was evaluated. A study of acute toxicity revealed focal liver cell necrosis. Another derivative, (R,S)3-[N,N-bis-(2-chloroethyl)]amino-1-(4'-n-butoxyphenyl)pyrrolidine- 2,5-dione dihydrate (II), which also possessed significant anticancer effect on P388 and L1210 leukaemias, was inactive against Sarcoma 180.

Anti-tumour effect of alpha-amino N-substituted-pyrrolidin-2,5-dione-N-mustards on the growth of P388 lymphocytic leukaemia.

(R,S)alpha-[N,N-[bis (2-chloroethyl)]-amino]-N-(o-methoxyphenyl)-pyrrolidin-2,5-dione hydrochloride (I), a new nitrogen mustard incorporated into a 2,5-pyrrolidinedione ring system, was found to be active against P388 lymphocytic leukaemia when administered by i.p., s.c. and p.o. routes. The anti-tumour activity, exhibited by compound (I), against intracerebrally grafted P388 tumour is of interest. However, (R,S)alpha-[N,N-[bis (2-chloroethyl)]-amino]-N-(p-n-butoxyphenyl)-pyrrolidin-2,5-dione dihydrate (II), was found to be active against the P388 tumour following i.p. administration only.

Combined effect of cyclophosphamide and extracts of Crotalaria and Senecio plants on experimental tumours.

The combined effect of cyclophosphamide (CTX) and extracts of six patients belonging to Crotalaria and Senecio genera was assessed on experimental transplantable S180 (both ascitic and solid forms) tumour. Successive petroleum ether and methanolic extracts from these plants were obtained. The combined administration of CTX and petroleum ether extract of C. albida and the methanolic extracts of C. albida, S. chrysanthemoides, S. densiflorus and S. jacquemontianus led to prolonging the life span of S180 (ascitic) tumour bearing mice. The data indicate that the most effective extract in combination with CTX was the methanolic extract of S. chrysanthemoides. The extracts alone had no effect on survival of tumour-bearing mice. The same extracts and the same combinations had no effect on S180 solid tumour.

Acute toxicity of folic acid in mice.

The toxicity of folic acid (PGA) was studied in different inbred strains of mice. LD50 values of PGA by the i.p. route showed a unique toxicity pattern. In some strains, convulsions, ataxia and weakness were observed. Histopathological study in strains S/RVCri, BDF1, DBA/2 and DBA/2fNCri showed acute renal tubular necrosis.

Pharmacokinetics of methotrexate in adult Indian patients and its relationship to nutritional status.

Since anticancer drugs have a low therapeutic index, any significant change in the pharmacokinetics of a drug would have a bearing on therapeutic efficacy and drug toxicity. Nutritional deficiencies have been shown to affect the four processes of pharmacokinetics, ie, absorption, distribution, biotransformation, and excretion. Malnutrition and undernutrition are widely prevalent in India and thus it was thought to be of practical importance to study the effect of initial nutritional status on the overall kinetics of methotrexate, a widely used anticancer drug. The results of the study reveal that relative weight correlates well with the anthropometric parameters, nutritional parameters, and dietary intake and may be used as a marker of nutritional status. When grouped on the basis of relative weights, the undernourished patients revealed a significant (P less than 0.01) prolongation of biological half-life and a significant (P less than 0.001) reduction in clearance. Based on these results, relative weight has been proposed as a basis for drug dosage determinations in place of the existing practice of administering antineoplastic drugs on the basis of body surface area or body weight alone.

Inability of amphotericin B(Fungizone) or of sodium deoxycholate to alter natural drug resistance or sensitivity of transplanted murine leukemias.

The ability of Amphotericin B ('Fungizone') to alter the natural resistance of leukemia L1210 to vincristine was studied in BDF1 mice Neither Fungizone nor the "solubilizing agent" sodium deoxycholate, when used in combination with vincristine potentiated the activity of the drug against L1210. There was no change in the activity pattern of 5-fluorouracil against L1210 or vincristine against P388 lymphocytic leukemia respectively, which are sensitive to these drugs. Thus, both Fungizone and sodium deoxycholate failed to improve the activity of the drugs in either a naturally resistant or sensitive murine leukemia in vivo.

Combination of anticancer agents with folic acid in the treatment of murine leukaemia P388.

Folic acid (FA) was combined with anticancer agents such as (i) antimetabolites like methotrexate (MTX), 5-fluorouracil (5-FU), arabinosyl cytosine (Ara-C) and 6-mercaptopurine (6-MP); (ii) plant-derived mitotic inhibitor, vincristine (VCR), and (iii) an antibiotic, mitomycin C (Mit-C). This combination modality was used for the treatment of P388 lymphocytic leukaemia. Large doses of FA were administered to the tumour-bearing mice either prior to or simultaneously with different anticancer agents. Pre-treatment with FA significantly improved the therapeutic efficacy of 5-FU, Ara-C and Mit-C; while MTX was more effective when given simultaneously with FA. The efficacy of 6-MP and VCR was not enhanced by FA when tested similarly. Large doses of FA can potentiate the activity of certain anticancer agents when administered to P388-bearing mice at critical times that vary according to the particular drug used.

Anti tumour and pharmacological effects of the oil from Semecarpus anacardium Linn. f.

Semecarpus anacardium Linn.f. nuts were extracted by using non-polar and polar organic solvents. Hot methanol extract and a resinous fraction, isolated from it, showed antitumour activity against P388 lymphocytic leukaemia in BDF1 mice as judged by their median survival time. Petroleum ether extract and its chromatographically isolated fraction were obtained. The latter fraction was distilled under reduced pressure to get an orange-coloured oil, (b.p. 200-20 degrees/2-3 mm). Both had antitumour activity. The orange-coloured oil, on further distillation under reduced pressure, yielded Bhilawanol. An acetyl derivative of the oil was also obtained. The latter two also had antitumour activity.