The Effects of Different Varieties of Aurantii Fructus Immaturus on the Potential Toxicity of Zhi-Zi-Hou-Po Decoction Based on Spectrum-Toxicity Correlation Analysis.

In accordance with the provision in China Pharmacopoeia, Citrus aurantium L. (Sour orange-SZS) and Citrus sinensis Osbeck (Sweet orange-TZS) are all in line with the requirements of Aurantii Fructus Immaturus (ZS). Both kinds of ZS are also marketed in the market. With the frequent occurrence of depression, Zhi-Zi-Hou-Po decoction (ZZHPD) has attracted wide attention. Currently, studies have shown that ZZHPD has a potential toxicity risk, but the effect of two commercial varieties of ZS on ZZHPD has not been reported. In this study, the toxicity differences of ZZHPD prepared by SZS and TZS were revealed through repeated administration experiments in rats. This indicated that different varieties of ZS could affect the toxicity of the prescription. In order to further study the chemical material basis of the toxicity difference, the fingerprints of ZZHPD prepared by different varieties of ZS were established by high-performance liquid chromatography (HPLC). Five different characteristic peaks were screened by non-target chemometrics. They were identified as geniposide, neoeriocitrin, naringin, hesperidin, and neohesperidin using an HPLC-time-of-flight mass spectrometry analyzer (TOF/MS) and an HPLC-triple stage quadrupole mass spectrometry analyzer (QqQ-MS/MS). Combined with a quantitative analysis and previous studies on promoting the intestinal absorption of geniposide, it is speculated that the synergistic effects of the components may be the main reason for the difference of toxicity among the different medicinal materials. This study provides a reference for the clinical, safe use of ZZHPD, and also provides a new perspective for the study of the potential toxic substances of traditional Chinese medicine compound preparations.

Fully Synthetic Heparan Sulfate-Based Neural Tissue Construct That Maintains the Undifferentiated State of Neural Stem Cells.

Heparin and heparan sulfate (HS) are attractive components for constructing biomaterials due to their ability to recruit and regulate the activity of growth factors. The structural and functional heterogeneity of naturally derived heparin and HS is, however, an impediment for the preparation of biomaterials for regenerative medicine. To address this problem, we have prepared hydrogels modified by well-defined synthetic HS-derived disaccharides. Human induced pluripotent cell-derived neural stem cells (HIP-NSCs) encapsulated in a polyethylene glycol-based hydrogel modified by a pendent HS disaccharide that is a known ligand for fibroblast growth factor-2 (FGF-2) exhibited a significant increase in proliferation and self-renewal. This observation is important because evidence is emerging that undifferentiated stems cells can yield significant therapeutic benefits via their paracrine signaling mechanisms. Our data indicate that the HS disaccharide protects FGF-2, which has a very short biological half-live, from degradation. It is anticipated that, by careful selection of a synthetic HS oligosaccharide, it will be possible to control retention and release of specific growth factor, which in turn will provide control over cell fate.

Safety Assessment of Monosaccharides, Disaccharides, and Related Ingredients as Used in Cosmetics.

The Cosmetic Ingredient Review Expert Panel (Panel) assessed the safety of 25 monosaccharides, disaccharides, and related ingredients and concluded these are safe in the present practices of use and concentration described in the safety assessment. Many of these ingredients are common dietary sugars, dietary sugar replacements, or very closely related analogs and salts; 7 of the ingredients are listed by the Food and Drug Administration as generally recognized as safe food substances. The most commonly reported cosmetic function is as a skin-conditioning agent; other commonly reported functions are use as a humectant or as a flavoring agent. The Panel reviewed the animal and clinical data included in this assessment, acknowledged that the oral safety of many of these ingredients has been well established, and found it appropriate to extrapolate the existing information to conclude on the safety of all the monosaccharides, disaccharides, and related ingredients.

Effects of inhibition of hepatic sulfotransferase activity on renal genotoxicity induced by lucidin-3-O-primeveroside.

Sulfotransferase 1A (SULT1A) expression is lower in the liver of humans than that of rodents. Therefore, species differences should be taken into consideration when assessing the risk of rodent hepatocarcinogens metabolically activated by SULT1A in humans. Although some renal carcinogens require SULT1A-mediated activation, it is unclear how SULT1A activity in the liver affects renal carcinogens. To explore the effects of SULT1A activity in the liver on genotoxicity induced by SULT1A-activated renal carcinogens, B6C3F1 mice or gpt delta mice of the same strain background were given lucidin-3-O-primeveroside (LuP), a hepatic and renal carcinogen of rodents, for 4 or 13 weeks, respectively, and pentachlorophenol (PCP) as a liver-specific SULT inhibitor, was given from 1 week before LuP treatment to the end of the experiment. A 4 week exposure of LuP induced lucidin-specific DNA adduct formation. The suppression of Sult1a expression was observed only in the liver but not in the kidneys of PCP-treated mice, but co-administration of PCP suppressed LuP-induced DNA adduct formation in both organs. Thirteen-week exposure of LuP increased mutation frequencies and cotreatment with PCP suppressed these increases in both organs. Given that intact levels of SULT activity in the liver were much higher than in the kidneys of rodents, SULT1A may predominantly activate LuP in the liver, consequently leading to genotoxicity not only in the liver but also in the kidney. Thus, species differences should be considered in human risk assessment of renal carcinogens activated by SULT1A as in the case of the corresponding liver carcinogens.

Cyclosporine A as a Cardioprotective Agent During Donor Heart Retrieval, Storage, or Transportation: Benefits and Limitations.

BACKGROUND: Storage of donor hearts in cardioplegic solutions supplemented with conditioning agents activating endogenous mitochondrial protective signaling enhanced their postreperfusion recovery. The present study investigates the role of timing and duration of cardiac exposure to cyclosporine A (CsA), another putative mitochondrial protectant, on cardiac functional recovery and potential mechanisms of CsA action in an isolated working rat heart model of donor heart retrieval and storage. METHODS: After measurement of baseline function, hearts were arrested and stored for 6 hours at 4°C in either Celsior alone or Celsior + CsA (0.2 µM), then reperfused for 45 minutes in Krebs solution, when functional recovery was assessed. Two additional groups of Celsior-alone stored hearts were exposed to 0.2 µM CsA for the initial 15 minutes (nonworking period) or the full 45-minute period of reperfusion. Coronary effluent was collected pre- and poststorage for assessment of lactate dehydrogenase release. Tissue samples were collected at the end of each study for immunoblotting and histological studies. RESULTS: CsA supplementation during cold storage or the first 15-minute reperfusion significantly improved functional recovery and significantly increased phospho-AMPKαThr172 and phospho-ULK-1Ser757. Hearts exposed to CsA for 45 minutes at reperfusion recovered poorly with no phospho-AMP-activated protein kinase α activation, decreased phospho-eNOSSer633, and decreased mitochondrial cytochrome c content with increased lactate dehydrogenase release. CONCLUSIONS: Inclusion of CsA during cold storage is cardioprotective. Effects of CsA addition to the perfusate during reperfusion were time dependent, with benefits at 15 minutes but not 45 minutes of reperfusion. The toxic effect with the presence of CsA for the full 45-minute reperfusion is associated with impaired mitochondrial integrity and decreased eNOS phosphorylation.

Attenuation of isoproterenol-induced cardiotoxicity in rats by Narirutin rich fraction from grape fruit.

BACKGROUND: Oxidative stress is one of the major mechanism involved in pathogenesis of myocardial infarction. Use of natural products as therapeutic approach for ischemic myocardial injury is gaining attention worldwide. PURPOSE: This study was designed to investigate efficacy of Narirutin rich fraction (NRF), obtained from grape fruit peel, in the treatment of isoproterenol induced myocardial infarction in rats. METHODS: After 3-days pretreatment with NRF (100  mg/kg and 200  mg/kg, p.o.) myocardial injury was induced by subcutaneous administration of isoproterenol (85  mg/kg) for 2 days. Hemodynamic parameters, biochemical parameters, histological and ultrastructural changes were observed. RESULTS: Isoproterenol induced myocardial injury was evidenced by significant alterations in ECG, mean arterial pressure and left ventricular functions. Myocardial creatine kinase-MB isoenzyme, lactate dehydrogenase, superoxide dismutase, catalase, and glutathione level were reduced while MDE levels were increased. Histological findings also showed severe changes. Treatment with NRF significantly attenuated these parameters in dose dependent manner. CONCLUSION: Thus, present study provides evidences for efficacy of NRF against isoproterenol induced myocardial infarction in rats.

Ameliorative effect of pumpkin seed oil against emamectin induced toxicity in mice.

The current study was conducted to evaluate the toxic effects of emamectin insecticide in mice and the possible protective effect of pumpkin seed oil. Treated mice received emamectin benzoate in the diet at 75-ppm for 8 weeks, while another group of animals received emamectin in addition to pumpkin seed oil at a dose of 4 ml/kg. Biochemical analysis of MDA, DNA fragmentation, GSH, CAT and SOD was performed in liver, kidney and brain as oxidant/antioxidant biomarkers. In addition, gene expression of CYP2E1 and Mgst1 and histopathological alterations in these organs were evaluated. Emamectin administration induced oxidative stress in liver and kidney evidenced by elevated levels of MDA and percentage of DNA fragmentation with suppression of GSH level and CAT and SOD activities. Brain showed increase of MDA level with inhibition of SOD activity. Relative expressions of CYP2E1 and Mgst1 genes were significantly elevated in both liver and kidney. Emamectin produced several histopathological changes in liver, kidney and brain. Co-administration of pumpkin seed oil produced considerable protection of liver and kidney and complete protection of brain. In conclusion, pumpkin seed oil has valuable value in ameliorating the toxic insult produced by emamectin in mice.

Effect of some commonly used pesticides on seed germination, biomass production and photosynthetic pigments in tomato (Lycopersicon esculentum).

Pesticides are highly toxic substances. Their toxicity may not be absolutely specific to the target organisms but can adversely affect different processes in the non-target host plants. In the present study, the effect of over application of four commonly used pesticides (emamectin benzoate, alpha-cypermethrin, lambda-cyhalothrin and imidacloprid) was evaluated on the germination, seedling vigor and photosynthetic pigments in tomato. The obtained results revealed that seed germination was decreased by the pesticides and this effect was more prominent at early stages of exposure. All the tested pesticides reduced the growth of tomato when applied in higher concentration than the recommended dose, but at lower doses the pesticides had some stimulatory effects on growth as compared to the control. A similar effect of pesticides was observed on the photosynthetic pigments, i.e. a decrease in pigments concentrations was caused at higher doses but an increase was observed at lower doses of pesticides. The calculation of EC50 values for different parameters revealed the lowest EC50 values for emamectin (ranged as 51-181 mg/L) followed by alpha-cypermethrin (191.74-374.39), lambda-cyhalothrin (102.43-354.28) and imidacloprid (430.29-1979.66 mg/L). A comparison of the obtained EC50 values for different parameters of tomato with the recommended doses revealed that over application of these pesticides can be harmful to tomato crop. In a few cases these pesticides were found toxic even at the recommended doses. However, a field based study in this regard should be conducted to further verify these results.

Benzoylurea pesticides used as veterinary medicines in aquaculture: Risks and developmental effects on nontarget crustaceans.

Diflubenzuron and teflubenzuron are benzoylureas that are used in aquaculture to control sea lice. Flubenzurons have low toxicity to many marine species such as fish and algae but by their nature are likely to have significant adverse effects on nontarget species such as crustaceans and amphipods. Although the exact mechanism of toxicity is not known, these compounds are thought to inhibit the production of the enzyme chitin synthase during molting of immature stages of arthropods. These chitin synthesis inhibitors are effective against the larval and pre-adult life stages of sea lice. Due to their low solubility and results of recent monitoring studies conducted in Norway, the sediment compartment is considered the most likely reservoir for these compounds and possible remobilization from the sediment to benthic crustaceans could be of importance. For this reason, the epibenthic copepod Tisbe battagliai was selected for investigations into the acute and developmental effects of these compounds. For comparative purposes, azamethiphos was investigated to identify differences in sensitivity and act as a negative control for developmental effects at environmentally relevant concentrations. Standard acute studies with adult copepods showed little or no acute toxicity at milligrams per liter levels with the flubenzurons, whereas a naupliar developmental test demonstrated that environmentally relevant concentrations (e.g., nanograms per liter) caused a complete cessation of molting and finally death in the exposed copepods.

The minor structural difference between the antioxidants quercetin and 4'O-methylquercetin has a major impact on their selective thiol toxicity.

Antioxidants act as intermediates by picking up the high unselective reactivity of radicals and transferring it to other molecules. In this process the reactivity is reduced and becomes selective. This channeling of the reactivity can cause selective toxicity. The antioxidant quercetin is known to channel the reactivity towards thiol groups. The present study compares the thiol reactivity of quercetin with that of 4'O-methylquercetin (tamarixetin) towards creatine kinase (CK), a vital protein that contains a critical thiol moiety. Our results showed that oxidized quercetin and oxidized tamarixetin both adduct CK, which then loses its enzymatic function. Ascorbate, an important representative of the antioxidant network, is able to prevent adduction to and thus the inhibition of the enzyme by tamarixetin but not by quercetin. Apparently, tamarixetin is less thiol toxic than quercetin, because--rather than adduction to CK--tamarixetin quinone prefers to pass reactivity to the antioxidant network, i.e., to ascorbate. The findings exemplify that radical scavenging flavonoids pick up the reactivity of radicals and act as a pivot in directing the way the reactivity is channeled. A mere minor structural difference of only one methyl moiety between quercetin and tamarixetin appears to have a high impact on the selective, thiol toxicity.

Protective effects of bajijiasu in a rat model of Aß25₋35-induced neurotoxicity.

ETHNOPHARMACOLOGICAL RELEVENCE: Neurodegenerative diseases (NDs) caused by neurons and/or myelin loss lead to devastating effects on patients׳ lives. Although the causes of such complex diseases have not yet been fully elucidated, oxidative stress, mitochondrial and energy metabolism dysfunction, excitotoxicity, inflammation, and apoptosis have been recognized as influential factors. Current therapies that were designed to address only a single target are unable to mitigate or prevent disease progression, and disease-modifying drugs are desperately needed, and Chinese herbs will be a good choice for screening the potential drugs. Previous studies have shown that bajijiasu, a dimeric fructose isolated from Morinda officinalis radix which was used frequently as a tonifying and replenishing natural herb medicine in traditional Chinese medicine clinic practice, can prevent ischemia-induced neuronal damage or death. MATERIALS AND METHODS: In order to investigate whether bajijiasu protects against beta-amyloid (Aß25₋35)-induced neurotoxicity in rats and explore the underlying mechanisms of bajijiasu in vivo, we prepared an Alzheimer׳s disease (AD) model by injecting Aß25-35 into the bilateral CA1 region of rat hippocampus and treated a subset with oral bajijiasu. We observed the effects on learning and memory, antioxidant levels, energy metabolism, neurotransmitter levels, and neuronal apoptosis. RESULTS: Bajijiasu ameliorated Aß-induced learning and memory dysfunction, enhanced antioxidative activity and energy metabolism, and attenuated cholinergic system damage. Our findings suggest that bajijiasu can enhance antioxidant capacity and prevent free radical damage. It can also enhance energy metabolism and monoamine neurotransmitter levels and inhibit neuronal apoptosis. CONCLUSION: The results provide a scientific foundation for the use of Morinda officinalis and its constituents in the treatment of various AD. Future studies will assess the multi-target activity of the drug for the treatment of AD.

High-content screening assay for identification of chemicals impacting spontaneous activity in zebrafish embryos.

Although cell-based assays exist, rapid and cost-efficient high-content screening (HCS) assays within intact organisms are needed to support prioritization for developmental neurotoxicity testing in rodents. During zebrafish embryogenesis, spontaneous tail contractions occur from late-segmentation (∼19 h postfertilization, hpf) through early pharyngula (∼29 hpf) and represent the first sign of locomotion. Using transgenic zebrafish (fli1:egfp) that stably express eGFP beginning at ∼14 hpf, we have developed and optimized a 384-well-based HCS assay that quantifies spontaneous activity within single zebrafish embryos after exposure to test chemicals in a concentration-response format. Following static exposure of one embryo per well from 5 to 25 hpf, automated image acquisition procedures and custom analysis protocols were used to quantify total body area and spontaneous activity in live embryos. Survival and imaging success rates across control plates ranged from 87.5 to 100% and 93.3-100%, respectively. Using our optimized procedures, we screened 16 chemicals within the US EPA's ToxCast Phase-I library, and found that exposure to abamectin and emamectin benzoate-both potent avermectins-abolished spontaneous activity in the absence of gross malformations. Overall, compared to existing locomotion-based zebrafish assays conducted later in development, this method provides a simpler discovery platform for identifying potential developmental neurotoxicants.

Using organic-certified rather than synthetic pesticides may not be safer for biological control agents: selectivity and side effects of 14 pesticides on the predator Orius laevigatus.

The generalist predator Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) is a key natural enemy of various arthropods in agricultural and natural ecosystems. Releases of this predator are frequently carried out, and it is included in the Integrated Pest Management (IPM) programs of several crops. The accurate assessment of the compatibility of various pesticides with predator activity is key for the success of this strategy. We assessed acute and sublethal toxicity of 14 pesticides on O. laevigatus adults under laboratory conditions. Pesticides commonly used in either conventional or organic farming were selected for the study, including six biopesticides, three synthetic insecticides, two sulfur compounds and three adjuvants. To assess the pesticides' residual persistence, the predator was exposed for 3d to pesticide residues on tomato sprouts that had been treated 1 h, 7 d or 14 d prior to the assay. The percentage of mortality and the sublethal effects on predator reproductive capacity were summarized in a reduction coefficient (E(x)) and the pesticides were classified according to the IOBC (International Organization for Biological Control) toxicity categories. The results showed that the pesticides greatly differed in their toxicity, both in terms of lethal and sub lethal effects, as well as in their persistence. In particular, abamectin was the most noxious and persistent, and was classified as harmful up to 14 d after the treatment, causing almost 100% mortality. Spinosad, emamectin, metaflumizone were moderately harmful until 7 d after the treatment, while the other pesticides were slightly harmful or harmless. The results, based on the combination of assessment of acute mortality, predator reproductive capacity pesticides residual and pesticides residual persistence, stress the need of using complementary bioassays (e.g. assessment of lethal and sublethal effects) to carefully select the pesticides to be used in IPM programs and appropriately time the pesticides application (as function of natural enemies present in crops) and potential releases of natural enemies like O. laevigatus.

Evaluation of toxicity and oxidative stress induced by intravenous iron isomaltoside 1000 in a nonclinical model.

The physicochemical characteristics of intravenous iron complexes affect the extent of weakly-bound iron and thus the degree of oxidative stress. The new preparation iron isomaltoside 1000 (IIM) was compared to iron sucrose (IS) and a control group in terms of biochemistry, oxidative stress, inflammatory markers and iron deposition in the liver, heart and kidneys of healthy rats. Renal function was significantly impaired in the IIM group versus both IS and controls. Liver enzymes were also significantly higher in IIM-treated animals versus the other groups, indicative of hepatic injury. Systolic blood pressure was significantly lower following IIM administration compared to IS or control animals. Oxidative stress in the liver, heart and kidneys was greater in the IIM group, as indicated by significantly increased levels of malondialdehyde and antioxidant enzyme activity, accompaniedby a significantly lower ratio of reduced to oxidized glutathione. Microscopy demonstrated more extensive positive staining for iron, and a smaller area of ferritin staining, in the liver, heart and kidneys of rats treated with IIM versus IS.Levels of the inflammatory markers TNF-alpha and IL6 were both significantly higher in the IIM group versus IS in all assessed tissues. These findings indicate that IIM has a less favorable safety profile than IS in healthy rats, adversely affecting iron deposition, oxidative stress and inflammatory responses, with impaired liver and renal function.

Cross-resistance, mode of inheritance and stability of resistance to emamectin in Spodoptera litura (Lepidoptera: Noctuidae).

BACKGROUND: Spodoptera litura (F.) is a cosmopolitan pest that has developed resistance to several insecticides. The aim of the present study was to establish whether an emamectin-selected (Ema-SEL) population could render cross-resistance to other insecticides, and to investigate the genetics of resistance. RESULTS: Bioassays at G(1) gave resistance ratios (RRs) of 80-, 2980-, 3050- and 2800-fold for emamectin, abamectin, indoxacarb and acetamiprid, respectively, compared with a laboratory susceptible population Lab-PK. After three rounds of selection, resistance to emamectin in Ema-SEL increased significantly, with RRs of 730-fold and 13-fold compared with the Lab-PK and unselected (UNSEL) population respectively. Further studies revealed that three generations were required for a tenfold increase in resistance to emamectin. Resistance to abamectin, indoxacarb, acetamiprid and emamectin in UNSEL declined significantly compared with the field population at G(1). Furthermore, selection with emamectin reduced resistance to abamectin, indoxacarb and acetamiprid on a par with UNSEL. Crosses between Ema-SEL and Lab-PK indicated autosomal and incomplete dominance of resistance. A direct test of a monogenic model and Land's method suggested that resistance to emamectin was controlled by more than one locus. CONCLUSION: Instability of resistance and lack of cross-resistance to other insecticides suggest that insecticides with different modes of action should be recommended to reduce emamectin selection pressure.

Chemical structure determination of DNA bases modified by active metabolites of lucidin-3-O-primeveroside.

Lucidin-3-O- primeveroside (LuP) is one of the components of madder root (Rubia tinctorum L.; MR) which is reported to be carcinogenic in the kidney and liver of rats. Since metabolism of LuP generates genotoxic compounds such as lucidin (Luc) and rubiadin (Rub), it is likely that LuP plays a key role in MR carcinogenesis. In the present study, the chemical structures of Luc-specific 2'-deoxyguanosine (dG) and 2'-deoxyadenosine (dA) adducts following the reactions of dG and dA with a Luc carbocation or quinone methide intermediate derived from Acetoxy-Luc were determined by liquid chromatography with photodiode array and electron spray ionizaion-mass spectrometry (LC-PDA-ESI/MS). The identification of the two measurable adducts as Luc-N(2)-dG and Luc-N(6)-dA was confirmed by NMR analysis. Subsequently, using a newly developed quantitative analytical method using LC-ESI/MS, the formation of Luc-N(2)-dG and Luc-N(6)-dA from the reaction of calf thymus DNA with Luc in the presence of S9 mixture was observed. The fact that this reaction with Rub also gave rise to the same dG and dA adducts strongly suggests that Rub genotoxicity involves a metabolic conversion to Luc. The precise determination of the modified DNA bases generated by LuP and the method for their analysis may contribute to further comprehension of the mode of action underlying carcinogenesis by MR and related anthraquinones.

Unsaturated genistein disaccharide glycoside as a novel agent affecting microtubules.

Genistein, due to its recognized chemopreventive and antitumor potential, is a molecule of interest as a lead compound in drug design. While multiple molecular targets for genistein have been identified, so far neither for this isoflavonoid nor for its natural or synthetic derivatives disruption of microtubules and mitotic spindles has been reported. Here we describe such properties of the synthetic glycosidic derivative of genistein significantly more cytotoxic than genistein, 7-O-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-(1-->4)-(6-O-acetyl-hex-2-ene-alpha-D-erythro-pyranosyl)genistein, shortly named G21. We found that G21 causes significant mitotic delay, frequent appearance of multipolar spindles, and alteration of the interphase microtubule array.

Structure-toxicity relationship of aminoglycosides: correlation of 2'-amine basicity with acute toxicity in pseudo-disaccharide scaffolds.

A new pseudo-disaccharide NB23 with a 3',4'-methylidene protection was designed and its properties were evaluated in comparison to other two structurally related pseudo-disaccharides. The basicity of the 2'-amine was found to be well correlated to acute toxicity data in mice: the increase in the basicity is associated with the toxicity increase. Based on these data, a new pseudo-trisaccharide NB45 was constructed. NB45 exhibited significant antibacterial activity while at the same time retained low acute toxicity.

Inherent toxicity of organ preservation solutions to cultured hepatocytes.

Organ preservation solutions have been designed to protect grafts against the injury inflicted by cold ischemia. However, toxicity of University of Wisconsin (UW) solution during rewarming has been reported. Therefore, we here assessed the toxicity of UW, histidine-tryptophan-ketoglutarate (HTK), Euro-Collins, histidine-lactobionate (HL), sodium-lactobionate-sucrose and Celsior solutions in cultured hepatocytes under hypothermic (4 degrees C), intermediate (21 degrees C) and physiological (37 degrees C) conditions. Marked toxicity of UW, HTK, HL and Euro-Collins solutions was observed at both 37 and 21 degrees C. With the exception of UW solution, these solutions also increased cell injury during cold incubation (LDH release after 18 h at 4 degrees C: HTK 76+/-2%, Euro-Collins 78+/-17%, HL 81+/-15%; control: Krebs-Henseleit buffer 20+/-6%). Testing of individual components using modified Krebs-Henseleit buffers suggested that histidine and phosphate are responsible for (part of) this toxicity. These potential toxicities should be taken into account in the development of future preservation solutions.

A 28-day oral (dietary) toxicity study of sucromalt in Sprague--Dawley rats.

A new sweetener, sucromalt, was produced via enzymatic conversion of sucrose and maltose to a mixture of fructose, leucrose and gluco-oligosaccharides. The present study evaluated the safety of this sweetener when administered as a dietary admix at concentrations of 50, 100 and 200 g/kg to Sprague-Dawley rats for 28 days. There were no treatment-related effects on the general condition and behavior as determined by clinical observations, functional observational battery and locomotor activity assessments. Evaluation of clinical pathology parameters revealed no toxicologically-relevant treatment-related effects on hematology, serum chemistry or urinalysis. Macroscopic and microscopic findings revealed no treatment-related effects on any organ evaluated. A treatment-related increase in mean food consumption was observed resulting in slightly higher body weight gains (2-4%) for both the male and female rats, which was not toxicologically relevant. Results of this study clearly demonstrate that consumption of high concentrations of sucromalt for 28 days is not associated with obvious signs of toxicity.