Production of d(−)-lactate from sucrose and molasses

Escherichia coli W3110 derivatives, strains SZ63 and SZ85, were previously engineered to produce optically pure D(-) and L(+)-lactate from hexose and pentose sugars. To expand the substrate range, a cluster of sucrose genes (cscR' cscA cscKB) was cloned and characterized from E. coli KO11. The resulting plasmid was functionally expressed in SZ63 but was unstable in SZ85. Over 500 mM D(-)-lactate was produced from sucrose and from molasses by SZ63(pLOI3501).     

(−)-Epingaione from Bontia daphnoides

(−)-Epingaione has been isolated as the major lipophilic metabolite of Bontia daphnoides, the only member of the Myoporaceae found in the West Indies.     

Isolation of R-(−)-3-Hydroxy-β-ionone from Burley Tobacco

The tritium-hydrogen exchange method was used to determine the total racemization of amino acid residues of four proteins (ribonuclease A, lysozyme, soybean protein and casein) during their exposure to an alkali. Tritium was incorporated with first order kinetics into these proteins during their incubation in 0.2 n NaOH at 40°C. The tritium-hydrogen exchange increased as the temperature and the alkali concentration increased. In contrast, pepsin digestibility decreased extensively in the initial stage of the treatment. This phenomenon was verified by the subsite theory of protease, that only minor racemization renders the extended range of the peptide chain around the racemized amino acids non-susceptible to pepsin. General precautions against the racemization of food protein treated with alkalis are discussed briefly in terms of the deterioration of nutrients.     

(−)-N-ethylcytisine,a lupin alkaloid from the flowers of Echinosophora koreensis

A new lupin alkaloid, (?)-N-ethylcytisine, was isolated from the fresh flowers of Echinosophora koreensis. Its structure has been confirmed b     

(−)-5,6-Dehydrocamphor from the antifungal essential oil of Zuccagnia punctata

The essential oils from aerial parts of nine populations of Zuccagnia punctata Cav. (Fabaceae) were obtained by hydrodistillation and analyzed by GC–FID, GC–MS and ¹³C NMR. A total of 80 constituents, mainly oxygenated monoterpenes, were identified representing from 79.0 to 95.2% of the total oils which showed different composition patterns. The unusual compound (?)-5,6-dehydrocamphor, the major constituent in six of the samples investigated with percentages ranging from 12.3% to 56.5%, was isolated for the first time from nature and its structure was completely defined from NMR spectrometric data. Microscope studies of leaves indicated that not only capitate glands but also non-glandular trichomes, not previously described in this species, were present on the leaf surfaces.The essential oil showed antifungal activity against the dermatophytes Microsporum gypseum, Tricophyton rubrum and T. mentagrophytes with MIC values between 15.6 and 125 μg ml^?1, being T. rubrum the most susceptible species.     

Discovery of a novel selective PPARγ modulator from (−)-Cercosporamide derivatives

In an investigation of (?)-Cercosporamide derivatives with a plasma glucose-lowering effect, we found that N-benzylcarboxamide derivative 4 was a partial agonist of PPARγ. A SAR study of the substituents on carboxamide nitrogen afforded the N-(1-naphthyl)methylcarboxamide derivative 23 as the most potent selective PPARγ modulator. An X-ray crystallography study revealed that compound 23 bounded to the PPARγ ligand binding domain in a unique way without any interaction with helix12. Compound 23 displayed a potent plasma glucose-lowering effect in db/db mice without the undesirable increase in body fluid and heart weight that is typically observed when PPARγ full agonists are administrated.     

Synthesis of (−)‐DAPD

A new synthesis of (?)‐DAPD, suitable for large scale development, is described.     

(−)-3β-Acetoxydrimenin from the leaves of Drimys winteri

A new natural product, 3β-acetoxydrimenin was isolated from the petrol extract of the leaves of Drimys winteri which also contains the known compounds safrol, drimenol and polygodial. The structure of the new compound was determined by chemical and spectroscopic methods.     

d-Ribulokinase from Klebsiella pneumoniae for continuous production of d-(−)-ribulose-5-phosphate

Summary The production of d-ribulose-5-phosphate in an enzyme membrane reactor was examined. Phosphoryl transfer from ATP to d-ribulose was catalysed by d-ribulokinase isolated from Klebsiella pneumoniae. For production of d-ribulose-5-phosphate the phosphoryl donor ATP was used either in stoichiometric or in catalytic amounts. Using catalytic amounts of ATP requires a second enzyme, e.g. pyruvate kinase, to regenerate ATP. The kinetic parameters for d-ribulokinase and pyruvate kinase were determined to calculate the performance of an enzyme membrane reactor for continuous production of d-ribulose-5-phosphate. Both processes operated for more than 200 h. Regardless of whether ATP was used in catalytic or stoichiometric amounts, about the same production parameters were determined. In continuous production space/time yields of 117 g (with ATP regeneration) and 103 g (without ATP regeneration) of d-ribulose-5-phosphate 1^–1 per day were reached.Offprint requests to: D. Gygax     

Isolation of (−)-1,2-dehydro-α-cyperone and solavetivone from Lycium chinense

The investigation of volatile components of Lycium chinense afforded (?)-1,2-dehydro-α-cyperone and solavetivone. (?)-1,2-Dehydro-α-cyperon     

In vivo and in silico anti-inflammatory mechanism of action of the semisynthetic (−)-cubebin derivatives (−)-hinokinin and (−)-O-benzylcubebin

(?)-Cubebin (CUB), isolated from seeds of Piper cubeba, was used as starting material to obtain the derivatives (?)-hinokinin (HK) and (?)-O-benzyl cubebin (OBZ). Using paw edema as the experimental model and different chemical mediators (prostaglandin and dextran), it was observed that both derivatives were active in comparison with both negative (5% Tween® 80 in saline) and positive (indomethacin) controls. The highest reduction in the prostaglandin-induced edema was achieved by OBZ (66.0%), while HK caused a 59.2% reduction. Nonetheless, the dextran-induced paw edema was not significantly reduced by either of the derivatives (HK or OBZ), which inhibited edema formation by 18.3% and 3.5%, respectively, in contrast with the positive control, cyproheptadine, which reduced the edema by 56.0%. The docking analysis showed that OBZ presented the most stable ligand-receptor (COX-2 – cyclooxygenase-2) interaction in comparison with CUB and HK.     

Isolation and Identification of (−)- Methylcitric Acid and 2-Methyl-cis-aconitic Acid from the Culture of Candida lipolytica

Human lactoferrin was produced in genetically engineered rice. N-linked glycan structures of recombinant human lactoferrin were determined. The oligosaccharides liberated by hydrazinolysis were labeled with 2-aminopyridine (PA). The PA-labeled glycans were purified by reverse-phase and size-fractionation HPLCs. The structures of these glycans were identified by HPLC, exoglycosidase digestion, and matrix-assisted laser desorption/ionization time-of-flight (MALDI–TOF) mass spectrometry. The glycan structures determined were ManFucXylGlcNAc₂ (3.4%), Man₂FucGlcNAc₂ (2.1%), Man₃FucGlcNAc₂ (2.5%), Man₃FucXylGlcNAc₂ (42.5%), two isomers of Man₂FucXylGlcNAc₂ (39.1%), Man₃XylGlcNAc₂ (6.5%), and Man₂XylGlcNAc₂ (3.9%).     

(−)Flacourtin,a phenolic glucoside ester from flacourtia indica

The bark of an Indian medicinal plant, Flacourtia indica, yielded a new phenolic glucoside ester, flacourtin, identified as 3-hydroxy-4-hydroxymeth     

Effect of the ratio of (+) and (−) mating type of Blakeslea trispora on carotene production from cheese whey in submerged fermentation

The effect of the ratio of (+) and (?) mating type of Blakeslea trispora on carotene production from deproteinized hydrolysed whey in shake flask culture was investigated. Also, the inoculum ratio of the two mating types on the morphology of the microorganism and the relationship between morphological changes of the fungus and product formation were studied. The concentration of carotenes was significantly affected by the ratio of (+) and (?) mating type of B. trispora. A ratio of 1:10 up to 1:100 of (+) and (?) type was found to achieve the highest carotene yields. The optimum ratio of the (+) and (?) mating types for the maximum pigment production (175.0 mg/g dry biomass at 8 days of fermentation) was found to be 1:10. The carotene content in B. trispora consisted of β-carotene, γ-carotene, and lycopene. At the maximum concentration of carotenes the proportion of β-carotene, γ-carotene, and lycopene (as percent of total carotenes) was 80, 12, and 8%, respectively. B.trispora growing in submerged fermentation is able to develop complex morphologies which have been classified into three major groups: freely dispersed hyphae, clumps and pellets. These parameters are strongly influence the production of carotenes.     

Metabolism of (−)-deprenyl and PF-(−)-deprenyl in brain after central and peripheral administration

We examined the cerebral metabolism of L-deprenyl and its fluoro-derivative pF-deprenyl, assaying the parent compounds, their metabolites desmethyl deprenyl, L-amphetamine, and L-methamphetamine, and the fluoro analogs of these metabolites. We compared the levels of the metabolites after subcutaneous injection with those after intracerebral administration (via microdialysis) of the parent compounds. The assay of the parent compounds and their metabolites was by GC-MS measurement of the components of brain microdialysate samples. After their subcutaneous administration, deprenyl and F-deprenyl rapidly entered the brain and then their concentration decreased, with an approximate half-life of 4.5 h. After the intracerebral administration the diffusion from the site of administration was minor. A small fraction (a few percent) of the intracerebrally administered deprenyl was metabolized in situ in the brain possibly by a nonenzymatic process. Metabolism of pF-deprenyl was somewhat more rapid. The higher cerebral levels of metabolites after the subcutaneous administration indicate their exogenous origin—metabolism of parent compounds in the periphery and penetration of the brain by the metabolites.     

(+)-Catechin is more bioavailable than (−)-catechin: Relevance to the bioavailability of catechin from cocoa

Catechin is a flavonoid present in fruits, wine and cocoa products. Most foods contain the (+)-enantiomer of catechin but chocolate mainly contains ( ? )-catechin, in addition to its major flavanol, ( ? )-epicatechin. Previous studies have shown poor bioavailability of catechin when consumed in chocolate. We compared the absorption of ( ? ) and (+)-catechin after in situ perfusion of 10, 30 or 50 μmol/l of each catechin enantiomer in the jejunum and ileum in the rat. We also assayed 23 samples of chocolate for (+) and ( ? )-catechin. Samples were analyzed using HPLC with a Cyclobond I-2000 RSP chiral column. At all concentrations studied, the intestinal absorption of ( ? )-catechin was lower than the intestinal absorption of (+)-catechin (p < 0.01). Plasma concentrations of ( ? )-catechin were significantly reduced compared to (+)-catechin (p < 0.05). The mean concentration of ( ? )-catechin in chocolate was 218 ± 126 mg/kg compared to 25 ± 15 mg/kg (+)-catechin. Our findings provide an explanation for the poor bioavailability of catechin when consumed in chocolate or other cocoa containing products.     

The neolignans (−)-carinatone and carinatin from Virola carinata

From the bark of Virola carinata two neolignans have been isolated: (?)-carcinatone, [(2S)-1-(3′,4′-dimethoxyphenyl)-2-(3″-allyl-5″-methoxy-6″-hydroxyphenyl) propanone] and carinatin, [5-allyl-7-methoxy-3-methyl-2-(3′,4′-dimethoxyphenyl)benzofuran].     

(−)-Epilamprolobine and its N-oxide,lupin alkaloids from Sophora tomentosa

From the fresh leaves of Sophora tomentosa, three new lupin alkaloids, (?)-epilamprolobine, (+)-epilamprolobine N-oxide and 5-(3′-methoxycarbonylbutyroyl)aminomethyl-trans-quinolizidine N-oxide, have further been isolated along with (+)-matrine, (+)-matrine N-oxide, (+)-sophocarpine N-oxide, (?)-anagyrine, (?)- baptifoline, (?)-cytisine, (?)-N-methylcytisine, (?)-N-formylcytisine, (?)-N-acetylcytisine and (±)-ammodendrine. The absolute configurations of (+)-epilamprolobine N-oxide (1R:5R:6S) and (?)-epilamprolobine (5R:6S) have also been established by spectroscopic data and by comparison with synthetic (+)-epilamprolobine (5S:6R)derived from (?)-lupinine (5R:6R). (?)-Epilamprolobine is a diastereomer of (+)-lamprolobine (5R:6R) in Lamprolobium fruticosum and 5-(3′-methoxycarbonylbutyroyl) aminomethyl-trans-quinolizidine N-oxide is presumed to be an artefact. A biosynthetic pathway for the formation of (?)-epilamprolobine is also proposed.