Volatile and non-volatile/semi-volatile compounds and in vitro bioactive properties of Chilean Ulmo (Eucryphia cordifolia Cav.) honey.

Ulmo honey originating from Eucryphia cordifolia tree, known locally in the Araucania region as the Ulmo tree is a natural product with valuable nutritional and medicinal qualities. It has been used in the Mapuche culture to treat infections. This study aimed to identify the volatile and non-volatile/semi-volatile compounds of Ulmo honey and elucidate its in vitro biological properties by evaluating its antioxidant, antibacterial, antiproliferative and hemolytic properties and cytotoxicity in Caco-2 cells. Headspace volatiles of Ulmo honey were isolated by solid-phase microextraction (SPME); non-volatiles/semi-volatiles were obtained by removing all saccharides with acidified water and the compounds were identified by GC/MS analysis. Ulmo honey volatiles consisted of 50 compounds predominated by 20 flavor components. Two of the volatile compounds, lyrame and anethol have never been reported before as honey compounds. The non-volatile/semi-volatile components of Ulmo honey comprised 27 compounds including 13 benzene derivatives accounting 75% of the total peak area. Ulmo honey exhibited weak antioxidant activity but strong antibacterial activity particularly against gram-negative bacteria and methicillin-resistant Staphylococcus aureus (MRSA), the main strain involved in wounds and skin infections. At concentrations >0.5%, Ulmo honey reduced Caco-2 cell viability, released lactate dehydrogenase (LDH) and increased reactive oxygen species (ROS) production in a dose dependent manner in the presence of foetal bovine serum (FBS). The wide array of volatile and non-volatile/semi-volatile constituents of Ulmo honey rich in benzene derivatives may partly account for its strong antibacterial and antiproliferative properties important for its therapeutic use. Our results indicate that Ulmo honey can potentially inhibit cancer growth at least partly by modulating oxidative stress.

Identification of alkylbenzene sulfonate surfactants leaching from an acrylonitrile butadiene rubber as novel inhibitors of calcineurin activity.

Calcineurin (CN) is a Ca(2+)/calmodulin (CaM) dependent serine/threonine protein phosphatase and plays important role in several cellular functions in both higher and lower eukaryotes. Here we report inhibition of CN by linear alkylbenzene sulfonate. The clue to the finding was obtained while identifying the inhibitory material leaching from acrylonitrile butadiene rubber used for packing. Using standard dodecylbenzene sulfonate (C12-LAS), we obtained strong inhibition of CN with a half maximal inhibitory concentration of 9.3 µM, whereas analogs such as p-octylbenzene sulfonate and SDS hardly or only slightly affected CN activity. Three alkaline phosphatases, derived from shrimp, bacteria, and calf-intestine, which exhibit similar enzymatic activities to CN, were not inhibited by C12-LAS at concentrations of up to 100 µM. Furthermore, C12-LAS did not inhibit Ca(2+)/CaM-dependent myosin light chain kinase activity when tested at concentrations of up to 36 µM. The results indicate that C12-LAS is a potent selective inhibitor of CN activity.

[Effects of benzene and selenium on telomerase in mouse lymphocytes in vivo].

OBJECTIVE: To study the effects of benzene and selenium on telomerase in mouse lymphocytes in vivo and evaluate telomerase activity as an early marker of benzene effects on lymphocytes. METHODS: Male Kunming mice were divided randomly into 8 groups, including negative control group, reagent control group, 100 mg/kg benzene group, 200 mg/kg benzene group, 400 mg/kg benzene group, 200 mg/kg benzene + 0.75 mg/kg selenium group, 200 mg/kg benzene + 1.50 mg/kg selenium group and 200 mg/kg benzene + 3.00 mg/kg selenium group, 5 mice in each group. The mice in different groups were treated with different methods, once daily for 5 days. After 48 hours of the final exposure, lymphocytes were separated and the telomerase activities were detected with TRAPELISA. RESULTS: Compared with negative and reagent control groups, the telomerase activity was increased after treatment with different dose of benzene and at the dose of 100 mg/kg benzene group it was significantly increased (P < 0.01). At the dose of 200 mg/kg benzene + 0.75 mg/kg selenium group, it was significantly increased (P < 0.01). Compared with the counterpart treated with 200 mg/kg benzene group, the expression of telomerase was increased at the different concentrations after treatment with benzene combined with selenium and it was significantly increased at the dose of 200 mg/kg benzene + 0.75 mg/kg selenium group (P < 0.05). CONCLUSION: Increased telomerase activity in lymphocytes stimulated by benzene at different concentrations indicates activation and proliferation of these lymphocytes of mice in vivo. Telomerase activity is probably a sensitive early marker of lymphocyte proliferation by benzene. Selenium can upregulate the telomerase activity.

Larvicidal activity of bis(2-ethylhexyl) benzene-1,2-dicarboxylate from Sterculia guttata seeds against two mosquito species.

The larvicidal activities of various fractions of the hexane extract of the seeds of Sterculia guttata against larvae of Aedes aegypti and Culex quinquefasciatus were determined. Bis(2-ethylhexyl) benzene-1,2-dicarboxylate (1) was identified as one of the active principles, displaying chronic toxicity against both types of larvae, with LD50 values of 79 and 64 ppm, respectively.

S5 Lipase: an organic solvent tolerant enzyme.

In this study, an organic solvent tolerant bacterial strain was isolated. This strain was identified as Pseudomonas sp. strain S5, and was shown to degrade BTEX (Benzene, Toluene, Ethyl-Benzene, and Xylene). Strain S5 generates an organic solvent-tolerant lipase in the late logarithmic phase of growth. Maximum lipase production was exhibited when peptone was utilized as the sole nitrogen source. Addition of any of the selected carbon sources to the medium resulted in a significant reduction of enzyme production. Lower lipase generation was noted when an inorganic nitrogen source was used as the sole nitrogen source. This bacterium hydrolyzed all tested triglycerides and the highest levels of production were observed when olive oil was used as a natural triglyceride. Basal medium containing Tween 60 enhanced lipase production to the most significant degree. The absence of magnesium ions (Mg2+) in the basal medium was also shown to stimulate lipase production. Meanwhile, an alkaline earth metal ion, Na+, was found to stimulate the production of S5 lipase.

[Impulsive neuron activity of several structures of the brain after administration of benzene and its homologues]. / Impul'snaia aktivnost' neironov nekotorykh struktur golovnogo mozga pri vvedenii benzola i ego gomologov.

The obtained findings have shown that dominating inter-impulse intervals in the area of 1000 and more ms, and multimodality of their distribution occur in benzene, toluol, xylol injection within time-structure of some neurons activity of sensomotor cortex, hippocampus, thalamus and lateral hypothalamus. The particularities of neuronal activity of the studied structures were revealed by the injection of chemical substances in natural and artificially produced food motivation. The mechanism of neurons activity blockade in benzene and its homologous injection was suggested to be linked with their influence upon mediator process, and perhaps, peptide factors participating in the formation of neuronal activity.

Flowers of Hibiscus rosa-sinensis, a potential source of contragestative agent. III: Interceptive effect of benzene extract in mouse.

In mouse, oral administration of the benzene extract of Hibiscus rosa-sinensis flowers at a dose level of 1 gm/kg body weight/day from day 5-8 of gestation led to termination of pregnancy in about 92% of the animals. The effect was associated with a significant fall in peripheral level of progesterone and increase in uterine acid phosphatase activity, as measured on day 10. The ovary exhibited signs of luteolysis, and the corpus luteal delta 5-3 beta -hydroxysteroid dehydrogenase activity decreased markedly. The interceptive effect of the extract was prevented completely by exogenous progesterone (1 mg/mouse/day) or chorionic gonadotropin (1 I.U./mouse/day) and partially (62.5%) by exogenous prolactin (500 micrograms/mouse/day). In unilaterally pregnant mouse having trauma-induced deciduomata in the sterile horn, the extract caused resorption of the fetuses, and regression of the deciduomata accompanied by reduction in weight of the ovaries. Luteolysis, may be due to interference with the luteotropic influence, and a consequent fall in plasma level of progesterone have been suggested as the plausible cause of termination of pregnancy.

Increased amine turnover in several hypothalamic noradrenaline nerve terminal systems and changes in prolactin secretion in the male rat by exposure to various concentrations of toluene.

Subacute exposure of rats to varying concentrations of toluene vapours leads to increases of amine levels and turnover in several types of hypothalamic noradrenaline nerve terminal systems. Furthermore, the exposure of toluene in concentrations ranging from 80-3000 ppm and benzene (1500 ppm) produced differential effects on dopamine and noradrenaline turnover within various parts of the hypothalamus. These regions are involved in neuroendocrine regulation and disturbances in the secretion of prolactin were demonstrated after exposure to toluene.

Embryotoxicity of inhaled benzene in mice and rabbits.

The effect of inhaled benzene on embryonal and fetal development was assessed in mice and rabbits. CF-1 mice and New Zealand white rabbits were exposed to 0 or 500 ppm of benzene for 7 hr per day from days 6 through 15 (mice) and 6 through 18 (rabbits) of gestation. Little evidence of maternal toxicity was seen in either species. Although some signs of embryonal toxicity were observed in both mice and rabbits, a teratogenic effect was not discerned in either species inhaling 500 ppm of benzene.

Distribution of Fe59 in benzene and iomex treated rats.

The distribution of Fe59 in plasma and blood at various time intervals has been studied in control, benzene and iomex administered, and anemic rats. A significant difference between control and benzene, and iomex treated animals was observed in the rate of reappearance of Fe59 in blood circulation. The accumulation of Fe59 in various organs was noted at the end of 48 h. A significant increase in the radio-iron content was observed in bone marrow, spleen and liver of benzene and iomex treated rats as compared to those of control rats.

Mutagenic effects of petrol in Drosophila melanogaster I. Effects of benzene and 1,2-dichloroethane.

Commercial petrol and two of its components, benzene and 1,2-dichloroethane, were tested for mutagenicity in Drosophila melanogaster. The chemicals were given to larvae through their food supply. A genetically unstable sexlinked test system caused by a transposable genetic element was used. Mutagenicity was measured by the frequency of somatic mutations for eye pigmentation. Commercial petrol and 1,2-dichloroethane showed mutagenic activity. With the system used, benzene did not show any mutagenic activity. The high frequency of mutations induced by 1,2-dichloroethane indicate the existence in Drosophila of a metabolic activating system.

Activity of lysosomal beta-glucuronidase in leukocytes of rats exposed to benzene and sodium selenate.

Chronic exposure to benzene results in rats in the decrease of the lymphocyte count in the peripheral blood, the decrease of the beta-glucuronidase (BG) activity both in lymphocytes and neutrophilic granulocytes as well as in the damage to lysosomal apparatus of lymphocytes expressed in diffusion of the enzyme within the cell cytoplasm. Administration of selenium (sodium selenate) in dosis of 1.0 microgram/Kg during consecutive 10 days prior the exposure to benzene resulted in prevention of benzene-induced decrease of the BG activity in granulocytes and of a damage to lymphocyte lysosomes. Application of selenium in dosis of 5.0 microgram/Kg during the same time prior the exposure to benzene prevented the benzene-induced lymphocytopenia, induced the reactive increase of the granulocyte number, and caused, moreover, the prevention of the BG activity decrease in granulocytes. Simultaneously the increase of the BG-positive lymphocyte percentage was noted which was related to the increase of cells exhibiting the cytoplasmatic and extralysosomal localization of the enzyme. The results suggest that only smaller doses of sodium selenate prevented the damage to lysosomal membrane of lymphocytes induced by toxic effect of benzene.