Indrajit D. Desai

Iron fortification of domestic drinking water to prevent anemia among low socioeconomic families in Brazil

Iron deficiency anaemia is a most common micronutrient deficiency affecting mostly the low socioeconomic populations of the developing world. The objective of this study was to evaluate the feasibility of iron fortification of household drinking water to prevent iron deficiency anaemia among members of the low socioeconomic families of Southern Brazil. A total of 21 low socioeconomic families representing 88 subjects including 1-6 years old children whose haemoglobin level was between 10 and 12 g/dl were selected to participate in this study. Nine families in the control group were supplied with placebo solution and 12 families in the experimental group were supplied iron solution with ascorbic acid to be added to their domestic drinking water over a period of 4 months. The feasibility and acceptability of iron fortified drinking water was assessed through home visits and questionnaires. Blood samples were collected at the beginning and after 4 months of the study for the determination of haemoglobin and serum ferritin levels. The results of this study indicated that iron fortified drinking water was well received by the low socioeconomic families and that it was effective in improving the haemoglobin and serum ferritin levels. It can be concluded from this study that iron fortification of household drinking water is a simple and effective alternative for developing countries along with other technological approaches to iron fortification of foods.

Vitamin E content of crude and refined vegetable oils in Southern Brazil

Abstract In recent years there has been a trend toward increased use of vegetable oils in the diets of the Brazilian population. The objective of this study was to examine the vitamin E content of commonly used vegetable oils in crude form and in major fractions of oils obtained during industrial processing and refining procedures. Soybean, corn, redpalm, cottonseed, peanut, sunflower, ricebran, olive, and coconut oils were analyzed for α-tocopherol, the most active form of vitamin E, and for β-, γ-, and β-tocopherols, the less active forms of vitamin E, by the recent method of high-pressure liquid chromatography. It appears from our study that total tocopherol content is not the best indicator of vitamin E activity in vegetable oils and that the α-tocopherol equivalent and its ratio to polyunsaturated fatty acids (PUFA) are a more meaningful index of the vitamin E status of these oils. The α-tocopherol equivalent for Brazilian oils ranged from 33 mg/100 g for sunflower oil to about 13 mg/100 g for olive oil and only a trace amount for coconut oil. Most commonly used oils such as soybean, com, cottonseed, ricebran, and sunflower contain 17 to 33 mg α-tocopherol per 100 g of oil. The ratio of α-tocopherol equivalent to PUFA content (in mg/g) varied from 0.4 for soybean, corn, and sunflower oils to above 1 for olive and redpalm oils. None of the commonly used vegetable oils in Brazil, except coconut oil, had a value below the adequate ratio of 0.4. Processing and refining do cause some losses especially during steam deodorization, but major proportions of tocopherols, on average about 78%, are still retained in the refined oil. The data indicate that these vegetable oils are a primary source of vitamin E in the diet of this population.

Effects of ultrasonic homogenization of human milk on lipolysis, IgA, IgG, lactoferrin and bacterial content

Abstract Effects of ultrasonic homogenization of human milk on its lipolytic activity, IgA, IgG, lactoferrin and bacterial content were tested using milk from 42 different mothers. Homogenization carried out at temperatures lower than 45°C increased lipolytic activity to levels approaching those produced by bile salt stimulation and did not appreciably alter the other indices measured. Temperatures higher than 55°C during sonication fully inhibited the lipolytic activity, decreased IgA and IgG levels, and completely eliminated bacterial contaminants. Low-temperature ultrasonic homogenization of human milk could be suitable as a method to minimize fat losses during tube feeding because this method increases lipolytic activity without destroying IgA, IgG and lactoferrin.

Studies on fortification of refined soybean oil with all-trans-retinyl palmitate in Brazil : stability during cooking and storage

Abstract Fortification of foods is a well recognized approach to solving nutritional problems in many parts of the world and particularly so in the developing nations. Common vegetable oils such as soybean oil can potentially be utilized for fortification with vitamin A in countries like Brazil where production and consumption of vegetable oils has been increasing very rapidly in recent years. The objective of the present study was to verify such feasibility by fortifying soybean oil with vitamin A and testing its stability during storage under various conditions and during different ways of cooking and frying foods with oils. The results of this study clearly showed that vitamin A palmitate added to soybean oil was stable for up to 6 months in sealed metal cans stored at room temperature. The retention of vitamin A for 9 months of storage under similar conditions was 99% of the original. Various trials involving cooking rice and beans, the staple foods of Brazil, with vitamin A-fortified soybean oil, indicated that retention of vitamin A in cooked rice was 99% and in beans was 88% when cooked by boiling for 90 min, and 90% when cooked under pressure for 40 min. Trials with vitamin A-fortified soybean oil for frying potatoes under repeated conditions of frying and storage indicated that there was progressive loss of vitamin A in oil depending on the frequency of repeated use of the same oil for frying. More than 58% of vitamin A was still retained after use of fortified soybean oil for four repeated fryings of potatoes in the same oil. On the whole, the results of this study clearly demonstrate that vitamin A palmitate added to refined soybean oil remains stable during commonly used storage and cooking procedures and that fortification of vegetable oils is feasible in Brazil and possibly in other developing regions of the world.

Evaluation of the effect of heat treatment on the biological value of vitamin A fortified soybean oil

Abstract From the public health point of view, fortification with vitamin A of common edible vegetable oils is an important step towards the improvement of vitamin A status of populations in developing countries. Our recent study in Brazil has clearly shown that retinyl palmitate added to refined soybean oil remains stable during commonly used storage and cooking procedures and that fortification of commercial vegetable oils is feasible in Brazil and possibly in many other developing countries which principally use vegetable oils as a source of fat in their diet. The objective of this study was to investigate the biological value of vitamin A fortified soybean oil which has been subjected to various heat treatments similar to those encountered during cooking by boiling at 100°C and during repeated deep frying at 170°C. A standard rat bioassay procedure was used and evaluations were carried out based on food intake, weight gain, and levels of vitamin A in plasma and liver of test animals. The results of this study support our previous findings and indicate further that vitamin A palmitate in fortified soybean oil retains 100% of its biological value during cooking procedures requiring boiling at 100°C for about 20 minutes and that the biological value of vitamin A fortified soybean oil is reduced by about 50% after repeated use (4 times) of the same oil for deep frying at 170°C. Further studies are needed to confirm these findings in humans.

Feeding premature infants banked human milk homogenized by ultrasonic treatment.

Premature neonates fed ultrasonically homogenized human milk had better weight gain and triceps skin-fold thickness than did a control group given untreated human milk (p < 0.01) and also had lower fat loss during tube feeding (p < 0.01). Ultrasonic homogenization of human milk appears to minimize loss of fat and thus allows better growth of premature infants.

THE TOCOPHEROL, VITAMIN K, AND RELATED ISOPRENOID QUINONE COMPOSITION OF A UNICELLULAR RED ALGA (PORPHYRIDIUM CRUENTUM)1

The total lipids of axenically cultivated cells of Porphyridium cruentum were extracted with aqueous methanol‐chloroform mixture and fractionated into neutral and polar lipids by silicic acid column chromatography. Thin‐layer and reversed‐phase paper chromatographic analyses of the neutral lipid fractions revealed the occurrence of plastoquinones (PQ) A and C, vitamin K1 (K), ubiquinone‐10 (Q10), α‐tocopherol (α‐T), and α‐tocopherolquinone (α‐TQ) in the photoautotrophically cultured alga, and the same quinones but no tocopherol in the alga grown photoheterotrophically on glycerol. The plastoquinone A and vitamin K1 were isolated, identified, and estimated by spectroscopic methods. The results indicated the following decreasing order of concentrations: autotrophic culture, PQ A > K > Q10 > PQ C, α‐TQ, α‐T; heterotrophic culture, PQ A > Q10 > K > PQ C, α‐TQ. Except for the absence of plastoquinone B, the overall quinonoid composition was in general agreement with those previously reported for multicellular members of Rhodophyta, but the concentration level in total lipid was markedly lower.

Effect of heat treatment during cooking on the biological value of vitamin A fortified soybean oil in human

Our earlier studies have clearly shown that vitamin A in the form of retinyl palmitate added to refined soybean oil remains stable during cooking and storage and that fortification of commercial vegetable oils is feasible in Brazil and in other developing countries. The objective of the present study was to evaluate the biological value of vitamin A fortified soybean oil in normal adults by measuring the postabsorptive peak rise in plasma vitamin A and the total area under the absorption curve. Healthy subjects 20–51 years of age, serving as their own controls, were given a rice-based diet containing either unfortified soybean oil (control), or vitamin A fortified soybean oil added during cooking (cooked), or vitamin A fortified soybean oil added after cooking (uncooked). The results of this study demonstrated that vitamin A in the form of retinyl palmitate when added to soybean oil is well absorbed in human even after the heat treatment it received during cooking. It can be concluded from this study so f...

l-THREONINE DEAMINASE IN MARINE PLANKTONIC ALGAE. II. DISULFIDE AND SULFHYDRYL GROUP REQUIREMENTS OF ENZYME ACTIVITY IN TWO CRYPTOPHYTES1

The “biosynthetic”l threonine (deaminating) dehydratase of 2 cryptophytes (Chroomonas salina and Hemiselmis virescens) showed sensitive inhibition from all thiols tested (dithiothreitol, cysteine, etc.) but no effect from ascorbic acid or reduced NAD. By contrast, the enzyme activities from 5 noncryptophyceaen unicellular algae (2 cyanophytes, 1 rhodophyte, 1 diatom, 1 chlorophyte) were generally not affected by any of these reagents. The thiol reagent inhibition of the cryptophyte enzymes (1) achieved saturation with 60–70% reduction in activity, (2) was considerably reduced by pretreatment of the enzymes with l‐threonine and l‐isoleucine, and (3) was partially reversed by subsequent treatment with arsenite and exposure to air. It was deduced that such inhibitions were caused by thiol‐specific reduction of enzyme‐protein disulfide groups essential for the full expression of activity and that these groups were susceptible to ready reductive cleavage and oxidative restoration. This disulfide requirement, unique to the cryptophytes, may be the first recorded case of such a property of threonine dehydratase from all forms of life hitherto studied. The additional activity requirement of the cryptophyte enzymes for sulfhydryl groups (which requirement was common to all the algal enzymes) was confirmed (1) by the study of their sensitivity to inhibition from mercurials and disulfide‐sulfhydryl exchanging reagents, and (2) by the partial reversal of these inhibitions from subsequent treatment with dithio‐threitol. Both cryptophyte enzymes were densitized to feedback inhibition from l‐isoleucine by prior exposure to subinhibitory concentrations of HgCl2 or dithiodipyridine.