A 91-day feeding study in rats with caprenin

Current Role of Nanotechnology Used in Food Processing Industry to Control Food Additives and Exploring Their Biochemical Mechanisms

BACKGROUND

With the advent of food additives centuries ago, the human race has found ways to improve and maintain the safety of utility, augment the taste, color, texture, nutritional value, and appearance of the food. Since the 19th century, when the science behind food spoilage was discerned, the use of food additives in food preservation has been increasing worldwide and at a fast pace to get along with modern lifestyles. Although food additives are thought to be used to benefit the food market, some of them are found to be associated with several health issues at an alarming rate. Studies are still going on regarding the mechanisms by which food additives affect public health. Therefore, an attempt has been made to find out the remedies by exploiting technologies that may convey new properties of food additives that can only enhance the quality of food without having any systemic side effects. Thus, this review focuses on the applications of nanotechnology in the production of nano-food additives and evaluates its success regarding reduction in the health-related hazards collaterally maintaining the food nutrient value.

METHODOLOGY

A thorough literature study was performed using scientific databases like PubMed, Science Direct, Scopus, Web of Science for determining the design of the study, and each article was checked for citation and referred to formulate the present review article.

CONCLUSION

Nanotechnology can be applied in the food processing industry to control the unregulated use of food additives and to intervene in the biochemical mechanisms at a cellular and physiological level for the ensuring safety of food products. The prospective of nano-additive of chemical origin could be useful to reduce risks of hazards related to human health that are caused majorly due to the invasion of food contaminants (either intentional or non-intentional) into food, though this area still needs scientific validation. Therefore, this review provides comprehensive knowledge on different facets of food contaminants and also serves as a platform of ideas for encountering health risk problems about the design of improved versions of nano-additives.

Evaluation of structured lipids with behenic acid in the prevention of obesity

Obesity affects all social classes, making it necessary to develop effective products that aid weight loss or help prevent weight gain. The objective of this work was to study the anti-obesity effects of structured lipids (SL) obtained by enzymatic interesterification, based on olive oil, soy oil and fully hydrogenated crambe oil. Twenty-four C57Bl/6 mice were distributed into four experimental groups according to the diet consumed: Control Diet (CD), Structured Lipids Diet (SLD), High-fat Control Diet (HCD), High-fat Structured Lipids Diet (HSLD). The animals that were fed SLs presented a smaller weight gain, despite a larger intake of the diet. The lowest weight gain was reflected in reduced amounts of adipose tissue and lower liver weight. A significant increase in lipids excreted by the animals in the feces was observed, despite there being no sign of toxicity or presence of diarrhea. The animals that consumed the HSLD presented lower total and LDL-cholesterol, increased HDL-cholesterol and increased hepatic arachidonic acid and docosahexaenoic acid levels. In addition, they did not develop hepatic steatosis. The study therefore showed that SLs could play a major role in combating or preventing obesity and other resultant diseases, without producing side effects.

Relation between statistics and treatment-related changes obtained from toxicity studies in rats: if detected a significant difference in low or middle dose for quantitative values, this change is considered as incidental change?

The purpose of a toxicity test is to determine the no-observed-effect level (NOEL) of test substance through biological and pharmacological techniques. If the low dose not does show statistically significant and biologically relevant changes in the data evaluated in a study, the usual practice is to consider this dose as the NOEL. To overcome this, 6 types of techniques that seemed to be appropriate are presented in this paper by investigating the results of several domestic and foreign theses on toxicology. The most appropriate techniques appear to be the trend test, comparison between treatment group and historical control by t-test, and confirmation that all individual values lie within the 95% confidence interval (2 SD) of the historical control value, if a significant difference is admitted in the low dose.

90-Day repeated-dose toxicity study of licorice flavonoid oil (LFO) in rats

Licorice flavonoid oil (LFO) is a new functional food ingredient consisting of licorice hydrophobic polyphenols in medium-chain triglycerides (MCT). As part of a safety evaluation, a 90-day oral toxicity study in rats was conducted using an LFO concentrate solution (2.90% glabridin). Male and female animals were assigned to one of 12 groups (10 males or females per group) and received corn oil (negative control), MCT (vehicle control), or 400, 600, 800 or 1600 mg/kg of the LFO concentrate solution. In conclusion, LFO concentrate solution induced an anticoagulation effect in both sexes, although there was a clear sex difference. Based on these findings, it is concluded that the no-observed-adverse-effect level (NOAEL) for the LFO concentrate solution is estimated to be 800 mg/kg/day for female rats, and approximately 400 mg/kg/day for male rats.

Safety evaluation of a medium- and long-chain triacylglycerol oil produced from medium-chain triacylglycerols and edible vegetable oil

To reduce the incorporation of dietary lipids into adipose tissue, modified fats and oils have been developed, such as medium-chain triacylglycerols (MCT). Typical dietary lipids from vegetable oils, termed long-chain triacylglycerols (LCT), are degraded by salivary, intestinal and pancreatic lipases into two fatty acids and a monoacyl glycerol; whereas, MCT are degraded by the same enzymes into three fatty acids and the simple glycerol backbone. Medium-chain fatty acids (MCFA) are readily absorbed from the small intestine directly into the bloodstream and transported to the liver for hepatic metabolism, while long-chain fatty acids (LCFA) are incorporated into chylomicrons and enter the lymphatic system. MCFA are readily broken down to carbon dioxide and two-carbon fragments, while LCFA are re-esterified to triacylglycerols and either metabolized for energy or stored in adipose tissue. Therefore, consumption of MCT decreases the incorporation of fatty acids into adipose tissue. However, MCT have technological disadvantages precluding their use in many food applications. A possible resolution is the manufacture and use of a triacylglycerol containing both LCT and MCT, termed medium- and long-chain triacylglycerol (MLCT). This manuscript describes studies performed for the safety evaluation of a MLCT oil enzymatically produced from MCT and edible vegetable oil (containing LCT), by a transesterification process. The approximate fatty acid composition of this MLCT consists of caprylic acid (9.7%), capric acid (3.3%), palmitic acid (3.8%), stearic acid (1.7%), oleic acid (51.2%), linoleic acid (18.4%), linolenic acid (9.0%), and other fatty acids (2.9%). The approximate percentages of long (L) and medium (M) fatty acids in the triacylglyerols are as follows: L, L, L (55.1%), L, L, M (35.2%), L, M, M (9.1%), and M, M, M (0.6%). The studies included: (1) acute study in rats (LD50>5000 mg/kg); (2) 6 week repeat-dose safety study via dietary administration to rats (NOAEL of 3500 mg/kg/day), (3) in vitro genotoxicity studies using Salmonella typhimurium and Escherichia coli (negative at 5000 mg/plate), and (4) a four-week, placebo-controlled, double blind, human clinical trial utilizing 20 test subjects (no effects at 42 g MLCT/day). These data are corroborated by other studies published in the peer-reviewed literature on analogous MLCTs.

Effects of miglyol 812 on rats after 4 weeks of gavage as compared with methylcellulose/tween 80

Miglyol 812 is a medium-chain triglyceride used in toxicology studies as an excipient to improve test compound solubility/absorption. As part of a larger toxicology study, 15 Wistar Han IGS rats/sex/group were dosed by oral gavage for 4 weeks with 10 mL kg(-1) day(-1) of 100% Miglyol 812 or 0.5% methylcellulose/0.1% Tween 80 in water (MC-T) followed by 4 weeks without treatment to evaluate the potential effects of this excipient in long-term toxicology studies relative to a traditional excipient such as MC-T. Clinical signs evident during the dosing phase included soft and/or mucoid stool in 12/15 males and 11/15 females treated with Miglyol 812 but in no animals treated with MC-T. Animals treated with Miglyol 812 had a 6-7% statistically significant reduction in body weight gain as compared to MC-T-treated animals. Statistically significant changes in clinical chemistry parameters as compared to MC-T included decreased blood urea nitrogen (50% and 29% in males and females, respectively), increased cholesterol (1.6-fold and 1.5-fold in males and females, respectively), decreased total protein (6% and 8% in males and females, respectively), decreased globulins (15% and 11% in males and females, respectively), and increased triglycerides (2.8-fold and 1.7-fold in males and females, respectively). Absolute and relative thymic weights decreased 28% and 24%, respectively, in males, and 18% and 17%, respectively, in females without histological alterations. Histopathology revealed increased alveolar histiocytosis with focal interstitial inflammation in lungs in 5/10 males and 7/10 females treated with Miglyol 812 compared to only 1/10 males and 1/10 females treated with MC-T. All effects were reversible during the recovery period. Results of this study indicate that 100% miglyol 812 produces reversible gastrointestinal effects and decreases in body weight gains along with changes in several serum chemistry parameters. Therefore, it should not be considered innocuous when delivered by oral gavage in long-term rodent toxicology studies.

An investigation of the general, reproductive and postnatal developmental toxicity of Betapol, a human milk fat equivalent

Betapol consists of triglyceride fatty acids commonly found in vegetable and animal fats. A similarity to human milk fat indicated a potential use in infant formulae as well as for food use in general. To test the potential for substantial equivalence with a related food grade oil, palm oil, Betapol was fed to rats at 15% content in the diet using an augmented two-generation study, in order to obtain information on general (6 months), reproductive and postnatal developmental toxicity in a single study rather than separate studies. For comparison there were two control groups, namely a comparative control fed a diet containing 15% of food grade oil and a negative, or laboratory standard control fed a commercial rodent breeding diet (LAD), containing 2.3-4.7% fat. It was reasoned that if Betapol fed groups showed differences from the comparative control in the direction of the negative control these would reflect differences in the nutritional value of the high fat diets. Presence of a toxicant might be indicated by differences from the comparative control group opposite to the negative control group. The group fed 15% Betapol showed occasional, statistically significant differences from the comparative control group but the direction of difference was towards the negative control group and did not indicate the presence of an unexpected toxicant.

The toxicity of behenyl alcohol. I. Genotoxicity and subchronic toxicity in rats and dogs

The genotoxic potential of behenyl alcohol, a saturated long-chain (C22:0) fatty alcohol, was examined in the Ames Salmonella typhimurium reverse mutation assay, the gene mutation, and chromosome aberrations assays in Chinese hamster V79 cells, and the micronucleus assay in NMRI mice. Behenyl alcohol did not increase the number of revertants per plate compared to controls in the S. typhimurium assay, with or without metabolic activation. No significant increases in the number of mutant colonies or in structural chromosome aberrations were observed in Chinese hamster V79 cells. In addition, behenyl alcohol did not increase the frequency of bone marrow polychromatic erythrocyte (PCE) micronuclei in mice in vivo. In two subchronic toxicity studies, CD rats and beagle dogs were administered behenyl alcohol by oral gavage for at least 26 weeks at doses of 0, 10, 100, or 1000 mg behenyl alcohol/kg body weight/day for rats and 0, 20, 200, or 2000 mg behenyl alcohol/kg body weight/day for dogs. Adverse effects were not observed following gross and histopathological evaluations of dosed rats. Compound-related effects in dogs were limited to observations of pale feces, indicative of unabsorbed behenyl alcohol, at doses of 2000 mg/kg body weight/day. There were no histopathological changes observed in dogs dosed with behenyl alcohol. The no-observed-adverse-effect-level (NOAEL) for behenyl alcohol was 1000 mg/kg body weight/day for rats, and 2000 mg/kg body weight/day for dogs, the highest doses used in these studies.

Review of the toxicologic properties of medium-chain triglycerides

Medium chain triglycerides (MCTs) are a family of triglycerides, containing predominantly, caprylic (C(8)) and capric (C(10)) fatty acids with lesser amounts of caproic (C(6)) and lauric (C(12)) fatty acids. MCTs are widely used for parenteral nutrition in individuals requiring supplemental nutrition and are being more widely used in foods, drugs and cosmetics. MCTs are essentially non-toxic in acute toxicity tests conducted in several species of animals. In ocular and dermal irritation testing MCTs exhibit virtually no potential as ocular or dermal irritants, even with prolonged eye or skin exposure. MCTs exhibit no capacity for induction of hypersensitivity. Ninety-day toxicity tests did not result in notable toxicity, whether the product was administered in the diet up to 9375mg/kg body weight/day or by intramuscular (im) injection (up to 0. 5ml/kg/day, rabbits). There was no evidence that intravenous (iv) or dietary administration of MCTs adversely affected the reproductive performance of rats or resulted in maternal toxicity, foetal toxicity or teratogenic effects at doses up to 4.28g/kg body weight/day (iv) or 12,500mg/kg body weight/day (dietary). There was no evidence that dietary administration of MCTs adversely affected the reproductive performance of pigs or resulted in maternal toxicity, foetal toxicity or teratogenic effects at doses up to 4000mg/kg body weight/day in the diet. In rabbits, following iv administration, the maternal and foetal no-observed-adverse-effect levels (NOAELs) were between 1.0 and 4.28g/kg body weight/ day. A 2-year study in rats, conducted with a closely related compound (tricaprylin, a triglyceride with C(8) fatty acids), provided no evidence of a carcinogenic effect when the material was administered by oral gavage at levels up to 10ml/kg (9.54g/kg) per day. Although tricaprylin was found to be positive in one of five strains of Salmonella typhimurium in the presence of metabolic activation in an Ames mutagenicity assay, the results of the carcinogenicity test with tricaprylin and mutagenicity tests with caprylic acid indicate that MCTs do not have the potential to be carcinogenic or mutagenic. The safety of human dietary consumption of MCTs, up to levels of 1g/kg, has been confirmed in several clinical trials.

New insights into the utilization of medium-chain triglycerides by the neonate: observations from a piglet model

Because of their unique digestive and metabolic properties, medium-chain triglycerides (MCT) are used in a variety of nutritional settings, including use as a readily digestible energy source for the neonate. This review examines recent findings from our laboratory related to MCT digestion and metabolism that are drawn from a neonatal piglet model, but which may be clinically relevant to human infants. We have shown that MCT utilization improves rapidly with postnatal age (within 24 h), which is likely due to the ontogeny of pancreatic lipase. Additional data delineate the dramatic effects of emulsification and fatty acid chain length (within the medium-chain family) on utilization, with the suggestion that triacylhexanoate is utilized at the highest rate. Again, these effects are likely mediated via an increase in the kinetics of digestion rather than metabolism. Indeed, using both in vitro and in vivo radiotracer techniques, we were unable to detect metabolic differences among even-chain fatty acid homologues. However, studies with isolated hepatocytes have shown greater oxidation rates of odd-chain fatty acids compared with even-chain homologues, in part as a result of the anaplerotic potential of propionyl-CoA arising from odd-carbon fatty acid oxidation. In vivo radiotracer studies also showed an improvement in octanoate oxidation to CO2, with a concomitant reduction in urinary dicarboxylic acid excretion when colostrum-deprived piglets were supplemented with L-carnitine. Further metabolic research led to the novel finding that piglets have a very limited hepatic capacity to synthesize ketone bodies, and that acetate may be a relatively important product of hepatic fatty acid oxidation in this species.