Production of a new terpenoid from biotransformation of (-)-isolongifolanol by Aspergillus niger and suppression of SOS-inducing activity

Abstract

The stereoselective oxidation of (—)-isolongifolanol (1) with a longifolene skeleton by Aspergillus niger (NBRC 4414) as a biocatalyst and suppressive effect on umuC gene expression by chemical mutagens furylfuramid and AFB1 of the SOS response in Salmonella typhimurium TA1535/pSK1002 were investigated. Compound 1 was converted to a new terpenoid, (-)-(2S,8R)-8,12-dihydroxy-isolongifolanol (2). Its structure was determined by NMR, IR, specific rotation and mass spectrometry. The metabolites suppressed the SOS-inducing activity of furylfuramid and AFB₁ in the umu test. Compound 1 suppressed 51% of the SOS-inducing activity against furylfuramid at < 1.0 mM. Compound 2 suppressed 15% and 24% of the SOS-inducing activity against furylfuramid and AFB1 at < 1.0 mM respectively.     

Chinese plasma-derived products supply under the lot release management system in 2007–2011

In 2007, the Chinese State Food and Drug Administration (SFDA) implemented a management system for lot release of all plasma-derived products. Since then, there have been only a few systematic studies of the blood supply, which is a concern when considering the small amount of plasma collected per capita (approximately 3 L/1000 people). As a result, there may be a threat to the safety of the available blood supply. In this study, we examined the characteristics of the supply of Chinese plasma-derived products. We investigated the reports of lot-released biological products derived from all 8 national or regional regulatory authorities in China from 2007 to 2011. The market supply characteristics of Chinese plasma-derived products were analyzed by reviewing the changes in supply varieties, the batches of lot-released plasma-derived products and the actual supply. As a result, the national regulatory authorities can more accurately develop a specific understanding of the production and quality management information provided by Chinese plasma product manufacturers. The implementation of the lot release system further ensures the clinical validity of the plasma-derived products in China and improves the safety of using plasma-derived products. This work provides an assessment of the future Chinese market supply of plasma-derived products and can function as a theoretical basis for the establishment of hemovigilance.     

Superoxide Dismutases and Anti-Oxidants Protected Mice from no-Reflow and Necrotic Damage Induced by Ischemia

A simple method in mice was established to screen anti-ischemic compounds. Thirteen times binding of rubber ring (1 × 1 mm, d = 42 mm) for 4.5 hrs, swelled the paws of 60% mice applied and 14 times binding swelled only of 5% mice. Critically reversible limit lay between these conditions. “All or none” rule dominated the paw swelling perhap due to different endogenous anti-oxidants' levels of individual mice. Determination of paw reversibility at 90 min of recirculation, was proved to be suitable. Swollen paws at this time returned normal and the paws with no-reflow dropped out by muscle necrosis after several days. Intravenous (i.v.) bovine Cu, Zn-SOD and bacterial Mn-SOD (3 - 10 × 10⁴ U/kg) or liposomal Cu, Zn-SOD (0.3 - 3 × 10⁴ U/kg) were protective (35-50%) by 14 times binding. Allopurinol (10-100 mg/kg) and D-mannitol (3-30mg/kg) was effective (25-55%). Catalase (i.v., up to 10⁵ U/kg) showed little protection, but local injection of 100 U/kg resulted in 50% protection. Glutathione (30 mg/kg) was suppressive only by local injection suggesting the importance of administration route. Desferal, heparin and nitric oxide synthesis inhibitor showed some protection, but indomethacin, mepyramine, ascorbate, vitamin E and dexamethasone were without effect. Excess dosing of all anti-oxidants tested, dramatically decreased their effects demanding caution for therapeutic trials.     

Ultrasound-assisted aqueous extraction of total flavonoids and hydroxytyrosol from olive leaves optimized by response surface methodology

Abstract

Olive leaves were often extracted with methanol or ethanol at different proportions. In this study, ultrasound-assisted aqueous extraction was adopted for olive leaf extraction. The yields of total flavonoids (TF) and hydroxytyrosol (HT) were optimized by central composite experimental design. Two second-order polynomial equations were established to quantify the relationship between the responses and the processing parameters. Under the optimal condition of extracting at 60?°C for 60?min with the solvent-to-material ratio of 40, TF and HT amounted to 57.31?±?0.35 and 1.80?±?0.02?mg/g dry leaves (DL), respectively. The scavenging rate of all extracts against α, α-diphenyl-β-picrylhydrazyl (DPPH) and hydroxyl free radicals was screened. The integrated scores, representing both active ingredients and antioxidant capacity of the extracts, were calculated by principle component analysis (PCA). The optimal extract gained the highest score in PCA. In addition, compared to the extracts from 80% methanol to 44% ethanol, the ultrasound-assisted aqueous extract was richer in TF, HT, and polyphenols, while it also presented stronger ferric reducing antioxidant power (FRAP), but poorer strength to quench hydroxyl radicals. The study indicated that the aqueous extract of olive leaves may present broad potential opportunities in health-care sector.     

Differences between bacterial associations with two root types of Vicia faba L

Abstract

Differences between various inherent physiological characteristics of lateral roots and of taproots of faba bean plants (Vicia faba L.) have been described in the literature. The question as to whether distinct bacterial communities inhabit each of those root types calls for further investigation. This question was tackled using aeroponically grown plants, i.e., plants that were grown under conditions as homogeneous as possible. Samples of the apical 5 cm of taproots and of lateral roots were compared. Metabolic fingerprints of root bacterial communities were analyzed using the Biolog® assay. Specificity of colonization of the different root types by specific bacterial taxa was examined by the Real-Time Polymerase Chain Reaction (PCR) method. Root bacterial communities produced distinct metabolic fingerprints for each of the two root types. Herbaspirillum spp. were found to be associated with lateral roots but not with taproots both under non-saline and saline (50 mM NaCl) conditions. No significant differences were found in the abundance of bacteria with respect to either root type or salinity. It is concluded that different root types, even within single root systems, differ not only in their physiological traits but also in their bacterial associations. Such associations might have adaptive advantages.     

Vitamin K, 2,3-Epoxide And Quinone Reduction: Mechanism And Inhibition

The chemical and enzymatic pathways of vitamin K₁ epoxide and quinone reduction have been investigated. The reduction of the epoxide by thiols is known to involve a thiol-adduct and a hydroxy vitamin K enolate intermediate which eliminates water to yield the quinone. Sodium borohydride treatment resulted in carbonyl reduction generating relatively stable compounds that did not proceed to quinone in the presence of base. NAD(P)H:quinone oxidoreductase (DT-diaphorase. E.C. I.6.99.2) reduction of vitamin K to the hydroquinone was a significant process in intact microsomes. but 1/5th the rate of the dithiothreitol (DTT)-dependent reduction. No evidence was found for DT-diaphorase catalyzed reduction of vitamin K₁ epoxide, nor was it capable of mediating transfer of electrons from NADH to the microsomal epoxide reducing enzyme. Purified diaphorase reduced detergent- solubilized vitamin K, 10^?5 as rapidly as it reduced dichlorophenylindophenol(DCPIP). Reduction of 10 μM vitamin K, by200 μM NADH was not inhibited by 10μM dicoumarol. whereas DCPIP reduction was fully inhibited. In contrast to vitamin K, (menadione). vitamin K₁ (phylloquinone) did not stimulate microsomal NADPH consumption in the presence or absence of dicoumarol. DTT-dependent vitamin K epoxide reduction and vitamin K reduction were shown to be mutually inhibitory reactions. suggesting that both occur at the same enzymatic site. On this basis, a mechanism for reduction of the quinone by thiols is proposed. Both the DTT-dependent reduction of vitamin K₁ epoxide and quinone. and the reduction of DCPIP by purified DT-diaphorase were inhibited by dicoumarol, warfarin. lapachol. and sulphaquinoxaline     

Carbonic Anhydrase Inhibitors: Synthesis of Sulfonamides Incorporating 2, 4, 6–Trisubstituted-Pyridinium-Ethylcarboxamido Moieties Possessing Membrane-Impermeability and in Vivo Selectivity for the Membrane-Bound (CA IV) Versus the Cytosolic (CA I and CA II) Isozymes

A new approach is proposed for the selective in vivo inhibition of membrane-bound versus cytosolic carbonic anhydrase (CA, EC 4.2.1.1) isozymes with a class of positively-charged, membrane-impermeant sulfonamides. Aromatic/heterocyclic sulfonamides acting as strong (but unselective) inhibitors of this zinc enzyme were derivatized by the attachment of trisub-stituted-pyridinium-ethylcarboxy moieties (obtained from 2, 4, 6–trisubstituted-pyrylium salts and β-alanine) to the amino, imino, hydrazino or hydroxyl groups present in their molecules. Efficient in vitro inhibition (in the nanomolar range) was observed with some of the new derivatives against three investigated CA isozymes, i.e., hCA I, hCA II (cytosolic forms) and bCA IV (membrane-bound isozyme; h = human; b = bovine isozyme). Due to their salt-like character, the new type of inhibitors reported here, unlike the classical, clinically used compounds (such as acetazolamide, methazolamide, ethoxzolamide), are unable to penetrate biological membranes, as shown by CJ vivo and in vivo perfusion experiments in rats. The level of bicarbonate excreted into the urine of the experimental animals perfused with solutions of the new and classical inhibitors suggest that: (i) when using the new type of positively-charged sulfonamides. only the membrane-bound enzyme (CA IV) was inhibited. whereas the cytosolic isozymes (CA I and II) were not affected, (ii) in the experiments in which the classical compounds (acetazolamide, bcn-zolamíde. etc.) were used. unselective inhibition of all CA isozymes (I. II and IV) occurred.     

PHOTOBIOTREATMENT: INFLUENCE OF NITROGEN AND PHOSPHORUS RATIO IN WASTEWATER ON GROWTH KINETICS OF SCENEDESMUS OBLIQUUS

Nitrogen and phosphorus concentration in the effluent of a wastewater treatment plant can vary significantly, which could affect the growth kinetic and chemical composition of microalgae when cultivated in this medium. The aim of this work was to study the rate of growth, nutrient removal and carbon dioxide biofixation as well as biomass composition of Scenedesmus obliquus (S. obliquus) when it is cultivated in wastewater at different nitrogen and phosphorus ratio, from 1:1 to 35:1. A more homogeneous method for calculating productivities in batch reactors was proposed. The proper N:P ratio for achieving optimum batch biomass productivity ranged between 9 and 13 (263 and 322 mg L^?1 d^?1 respectively). This was also the ratio range for achieving a total N and P removal. Above and below this range (9–13) the maximum biomass concentration changed, instead of the specific growth rate.The maximum carbon dioxide biofixation rate was achieved at N:P ratio between 13 and 22 (553 and 557 mg CO2 L^?1 d^?1 respectively). Lipid and crude protein content, both depend on the aging culture, reaching the maximum lipid content (34%) at the lowest N:P (1:1) and the maximum crude protein content (34.2%) at the highest N:P (35:1).     

Synthesis of D‐Altritol Nucleosides with a 3′‐O‐Tert‐Butyldimethylsilyl Protecting Group

Four D‐altritol nucleosides with a 3′‐O‐tert‐butyldimethylsilyl protecting group are synthesized (base moieties are adenine, guanine, thymine and 5‐methylcytosine). The nucleosides are obtained by ring opening reaction of 1,5:2,3‐dianhydro‐4,6‐O‐benzylidene‐D‐allitol. Optimal reaction circumstances (NaH, LiH, DBU, phase transfer, microwave irridation) for the introduction of the heterocycles are base‐specific. For the introduction of the 3′‐O‐silyl protecting group, long reaction times and several equivalents of tert‐butyldimethylsilyl chloride are needed.