Safety studies conducted on a proprietary high-purity aloe vera inner leaf fillet preparation, Qmatrix.

The aloe vera plant has a long history of safe use for oral and topical applications. This publication describes safety studies conducted on a proprietary high-purity aloe vera inner leaf fillet preparation, Qmatrix. In a 13-week study in rats, Qmatrix was administered via gavage at 0, 500, 1000 and 2000 mg/kg body weight (bw)/day. There were no significant changes in food or water consumption, body weight, serum biochemistry or hematology at any of the doses tested. Sporadic, significant increases were observed in some of the measured urinalysis parameters; however, these variations were not treatment-related, as most were observed only in one sex, not dose-dependent and within historical control values. Organ weights were unaffected, except for a statistically significant, though not dose-dependent, increase in absolute and relative weights of the right kidney in males at 500 and 2000 mg/kg bw/day, respectively. Histopathological analysis revealed no abnormal signs. Qmatrix was non-mutagenic in an Ames test and a chromosomal aberration test at concentrations up to 10,000 microg/plate, and in an in vivo bone marrow micronucleus test at doses up to 5000 mg/kg bw/day. Based on these results, Qmatrix is not genotoxic in vitro or in vivo and; has an oral NOAEL greater than 2000 mg/kg bw/day following 90 days of oral exposure.

No evidence demonstrating hepatotoxicity associated with hydroxycitric acid.

Although a number of cases of hepatotoxicity are associated with the use of Hydroxycut weight management products, it has been alleged that their effects are primarily due to the presence of hydroxycitric acid (HCA, as Super CitriMax) in the formulations. However, while these products contain up to 20 different ingredients, some do not contain HCA. Case studies reported to date have not considered in depth the literature on the numerous animal and human studies that have been conducted on the safety and efficacy of HCA. No HCA-associated hepatotoxicity or treatment-related adverse effects have been reported in these studies, and thus it is premature to make the assumptions presented in the recent case studies regarding Hydroxycut. If it is established in well controlled studies that the use of these formulations with and/or without HCA can result in the occurrence or progression of hepatotoxicity, additional studies should be conducted to characterize the causative factor(s).

Literature review on the safety of Toyocerin, a non-toxigenic and non-pathogenic Bacillus cereus var. toyoi preparation.

Bacillus cereus var. toyoi is a naturally occurring, non-toxigenic and non-pathogenic strain of B. cereus. Safety studies were conducted on a B. toyoi preparation (Toyocerin, including but not limited to enterotoxicity, eye irritation, genotoxicity, acute, subchronic and chronic toxicity studies and human clinical trials. In rabbits, Toyocerin did not exhibit enterotoxicity and was only slightly irritating to the eyes. It was non-mutagenic in an Ames assay at up to 10,000 microg/plate and did not exhibit clastogenic activity in a chromosomal aberration test at up to 450 mg/ml. It was non-toxic in acute and repeated-dose (30 and 60 days and 1 year) toxicity studies in rats and mice at up to 3 x 10(11)spores/kg bw/day. In an eight-day human clinical trial, Toyocerin did not cause any adverse effects in healthy male and female subjects at 1 x 10(9) and 1 x 10(10)spores/kg bw/day. In feeding trials, Toyocerin not cause any adverse effects in rabbits, pigs, chickens, turkeys and cattle at doses ranging from 8.5 x 10(7) to 4 x 10(9)spores/kg bw/day for durations of 2 weeks to 18 months. Taken together, these studies demonstrate that Toyocerin is safe at the doses tested.

Safety studies conducted on high-purity trans-resveratrol in experimental animals.

trans-Resveratrol is a naturally occurring polyphenolic compound found in a variety of foods, but predominantly in grapes. Safety studies were conducted on high-purity trans-resveratrol (Resvida), including skin and eye irritation, dermal sensitization, subchronic and reproductive toxicity, genotoxicity, and absorption, metabolism and excretion. Resvida was non-irritating to skin and eyes and non-sensitizing. It was non-mutagenic in a bacterial reverse mutation assay in Salmonella typhimurium and Escherichia coli, but exhibited clastogenic activity in a chromosomal aberration test in human lymphocytes. However, in an in vivo bone marrow micronucleus test in rats, Resvida was non-genotoxic. In a 28-day study, Resvida caused no adverse effects in rats at 50, 150 and 500 mg/kg bw/day. Similarly, in a 90-day study, Resvida did not cause any adverse effects in rats at up to 700 mg/kg bw/day; the highest dose tested. Resvida did not induce any adverse reproductive effects in an embryo-fetal toxicity study in rats at a dose of 750 mg/kg bw/day. Also, in vitro and in vivo absorption, metabolism, and excretion studies in Caco-2 cells, rat primary hepatocytes and male and female rats (in vivo) show that Resvida is readily absorbed, metabolized and excreted. These studies provide evidence that Resvida is well tolerated and non-toxic.

Genotoxicity studies on a high-purity rebaudioside A preparation.

Rebaudioside A (Reb A) is a steviol glycoside isolated from the leaves of the Stevia rebaudiana plant. This non-nutritive, natural sweetener is reported to be 250-450 times sweeter than sucrose and has potential for wide use in the US diet, and is used in Japan and South America today. The safety of Reb A has been investigated in several recently published studies and information on genotoxicity is described herein. Reb A was investigated for its potential to induce genotoxicity in three in vitro and two in vivo assays (conducted according to OECD guidelines). Reb A was non-mutagenic in an Ames test using Salmonella typhimurium and Escherichia coli, in a chromosomal aberration test using Chinese Hamster V79 cells and in a mouse lymphoma assay using L5178Y+/- cells, all studies were conducted at concentrations up to 5000 microg/ml, with and without metabolic activation. Also, Reb A was non-genotoxic in a bone marrow micronucleus test in mice at doses up 750 mg/kg bw and in an unscheduled DNA synthesis test in rats at 2000 mg/kg bw. These studies provide additional evidence that Reb A is not genotoxic at the doses tested and further support the generally recognized as safe determination of Reb A.

Transformation-mediated complementation of a FUM gene cluster deletion in Fusarium verticillioides restores both fumonisin production and pathogenicity on maize seedlings.

The filamentous ascomycete Fusarium verticillioides is a pathogen of maize and produces the fumonisin mycotoxins. However, a distinct population of F. verticillioides is pathogenic on banana and does not produce fumonisins. Fumonisin-producing strains from maize cause leaf lesions, developmental abnormalities, stunting, and sometimes death of maize seedlings, whereas fumonisin-nonproducing banana strains do not. A Southern analysis of banana strains did not detect genes in the fumonisin biosynthetic gene (FUM) cluster but did detect genes flanking the cluster. Nucleotide sequence analysis of the genomic region carrying the flanking genes revealed that the FUM cluster was absent in banana strains except for portions of FUM21 and FUM19, which are the terminal genes at each end of the cluster. Polymerase chain reaction analysis confirmed the absence of the cluster in all banana strains examined. Cotransformation of a banana strain with two overlapping cosmids, which together contain the entire FUM cluster, yielded fumonisin-producing transformants that were pathogenic on maize seedlings. Conversely, maize strains that possess the FUM cluster but do not produce fumonisins because of mutations in FUM1, a polyketide synthase gene, were not pathogenic on maize seedlings. Together, the data indicate that fumonisin production may have been lost by deletion of the FUM cluster in the banana population of F. verticillioides but that fumonisin production could be restored by molecular genetic complementation. The results also indicate that fumonisin production by F. verticillioides is required for development of foliar disease symptoms on maize seedlings.

Fumonisin disruption of ceramide biosynthesis in maize roots and the effects on plant development and Fusarium verticillioides-induced seedling disease.

The fungus Fusarium verticillioides infects maize and produces fumonisins, inhibitors of ceramide synthase. Seeds of the cultivar Silver Queen were inoculated with fumonisin-producing or non-fumonisin-producing strains of F. verticillioides. Leaf lesion incidence and severity of effects on root and stalk growth were significantly correlated with fumonisin in roots and disruption of sphingolipid metabolism in roots. Uninoculated seeds grown in soil watered with solutions of fumonisin B1 exhibited above-ground symptoms indicative of F. verticillioides-induced seedling disease and dose-dependent reduction in root mass that was inversely correlated with fumonisin B1, sphingoid bases, and sphingoid base 1-phosphates in roots. There was also evidence of an adaptive response to disrupted sphingolipid metabolism in both the virulence and watering assays, suggesting induction of pathways responsible for metabolism of sphingoid base 1-phosphates after prolonged exposure. The results suggest that fumonisin, and its effects on sphingolipids, could contribute to all aspects of F. verticillioides maize seedling disease.

Fumonisin production and bioavailability to maize seedlings grown from seeds inoculated with Fusarium verticillioides and grown in natural soils.

The fungus Fusarium verticillioides infects maize and produces fumonisins. The purpose of this study was to determine the ability of F. verticillioides to produce fumonisins in synthetic and natural soils and their biological availability to maize roots. Maize seeds were inoculated with a pathogenic strain of F. verticillioides (MRC826) and planted in synthetic and three different natural soils. There were statistically significant reductions in stalk weight and root mass and increased leaf lesions in the MRC826-treated seedlings in all soil types. Fumonisins were detected in all of the soils of seedlings grown from MRC826-inoculated seeds. The fumonisin produced in the soils was biologically available to seedlings as demonstrated by the statistically significant elevation of free sphingoid bases and sphingoid base 1-phosphates in their roots. These results indicate that F. verticillioides produced fumonisins in the autoclaved synthetic and natural soils and that the fumonisin produced is biologically available on the basis of evidence of inhibition of ceramide synthase.

Fumonisin-ortho-phthalaldehyde derivative is stabilized at low temperature.

Fumonisins are water soluble mycotoxins produced by the fungus Fusarium verticillioides (formerly F. moniliforme). Fumonisin B(1) (FB(1)) is a diester of propane-1,2,3-tricarboxylic acid and 2-amino-12, 16-dimethyl-3,5,10,14,15-pentahydroxyeicosane, and is the most abundant of the naturally occurring fumonisins. Upon removal of the two tricarballylic acid side chains, the structure is referred to as hydrolyzed FB(1) (HFB(1)). FB(1) and HFB(1) are structurally similar to sphinganine, a sphingoid base. The fumonisins do not absorb UV light or fluoresce; therefore, derivatizing reagents are used for detection when separation is by high performance liquid chromatography (HPLC). The standard derivatizing reagent used for HPLC is ortho-phthalaldehyde (OPA) plus 2-mercaptoethanol (ME) reaction partner, however, the OPA-FB(1) derivative is not stable at room temperature. The objectives of this study were to: (1). determine the effect of temperature on the stability of the OPA-FB(1) derivative and (2). determine which structural characteristics of FB(1) contribute to the instability of the OPA-FB(1) derivative. The results indicate that OPA-FB(1), OPA-FB(3) and OPA-HFB(1) derivatives are unstable at 24 degrees C but that their stability improves significantly at 4 degrees C. The OPA-sphinganine derivative is stable for at least 24h at 24 degrees C. Thus, the instability of the OPA-FB(1) derivative may be attributed to its lack of a hydroxyl group at the carbon 1 position.

Total fumonisins are reduced in tortillas using the traditional nixtamalization method of mayan communities.

Fumonisin B1 (FB1) is a maize mycotoxin. In tortilla preparation, maize is treated with lime (nixtamalization), producing hydrolyzed FB1 (HFB1) due to loss of the tricarballylic acid side chains. This study determined the following: 1) whether nixtamalization by Mayan communities reduces total fumonisins, and 2) the steps in the process at which reduction occurs. Tortillas prepared by the traditional process contained FB1, FB2 and FB3 and their hydrolyzed counterparts. There were equimolar amounts of FB1 and HFB1 in the tortillas, but the total fumonisins were reduced 50%. The total FB1 plus HFB1 in the residual lime water and water washes of the nixtamal accounted for 50% of the total FB1 in the uncooked maize. HFB1 and FB1 were present in a 1:1 mol/L ratio in the water washes of the nixtamal, the masa dough and the cooked tortillas, whereas the ratio of HFB1:FB1 in lime water after steeping was 21. Water washes contained 11% of the FB1 that was in the uncooked maize. The results show that the traditional method reduced the total fumonisins in tortillas and reduced the sphinganine elevation (a biomarker closely correlated with fumonisin toxicity) in cells treated with extracts of tortillas compared with cells treated with extracts of contaminated maize.

Leaching and binding of fumonisins in soil microcosms.

Fumonisin B(1) (FB(1)) is a water-soluble mycotoxin produced by Fusarium verticillioides. Our research objectives were to determine the leaching of FB(1) through soils and FB(1) binding in soil. Leachate columns were used to determine the movement of FB(1) through soil. FB(1)-contaminated corn screenings or water extracts containing FB(1) were placed on the surface of soil columns. In 100% sand columns, FB(1) leaching was only slightly retarded, whereas at 50%, 75%, and 100% Cecil sandy loam, approximately 60%, 50%, and 20% of the FB(1) was recovered in the column leachate, respectively. The FB(1) retained on the 100% Cecil sandy loam column was tightly bound. However, approximately 75% of the bound FB(1) was released with 5% formic acid and 5% formic acid/acetonitrile (1:1), indicating that the nature of the interaction was probably ionic. The results suggest that FB(1) is quite stable in soils and, while tightly bound, under certain environmental conditions could be released.