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We report how an induction cooker for household use can be modified for heating substrate or heating gases to high temperature in a chemical vapor deposition system. Only minor changes of the cooker are necessary. Stable substrate temperature as high as 900 °C was achieved with input power of about 1150 W. [ABSTRACT FROM AUTHOR]

Short-chain carboxylic acids (SCCAs) that are naturally produced by microbial fermentation play an essential role in delaying microbial spoilage. SCCAs are structurally diverse, but only a few of them are routinely used in food biopreservation. This study investigated the effects of environmental pH and intrinsic properties of 21 structurally different SCCAs on the antimicrobial and antibiofilm activity against Salmonella enterica . Inhibition of SCCA toward planktonic and biofilm growth of S. enterica was higher in an acidic environment (pH 4.5) that is common in fermented products, and for SCCA that possessed both a high acid dissociation strength (pK a ) (>4.0) and a positive hydrophobicity [octanol/water partition coefficient (log K ow )]. Crotonic and caproic acids were identified as SCCAs with potential as biopreservatives even at near-neutral pH. SCCA with hydrophilic groups such as lactic acid did not inhibit S. enterica at concentrations up to 50 mM, while SCCA with benzene or methyl groups or a double bond prevented S. enterica growth and biofilm formation. Stimulation of biofilm formation was observed for formic, acetic, and propionic acid close to the minimum inhibitory concentration to reduce 50% of cell density (MIC 50 ) of planktonic cells, and for citric and isocitric acid with an MIC 50 of ≥50 mM. The presence of low concentrations of formic and propionic acids during biofilm formation conferred protection during eradication possibly due to a pre-adaptation effect, yet two consecutive acid treatments were successful in eradicating biofilms if the first acid treatment was two- to threefold of the MIC 50 .IMPORTANCEThis study provides a systematic comparison on the antimicrobial and antibiofilm activity of more than 20 structurally different SCCAs against a common food pathogen. We tested the antimicrobial activity at controlled pH and identified the structure-dependent antimicrobial effects of SCCA without the confounding influence of acidification. The combined effect of pK a and log K ow was identified as an important feature that should be considered when deciding for a specific SCCA in the application as antimicrobial. Our results imply that additional phenomena such as the use of SCCA as substrate and cellular pre-adaption effects have to be taken into consideration. We finally present a two-step treatment as an efficient approach to eradicate biofilms, which can be applied for the disinfection of contact surfaces and manufacturing equipment. Results obtained here can serve as guidelines for application of SCCA to avoid the growth of food pathogens and/or to develop biopreserved food systems., Competing Interests: The authors declare no conflict of interest.

trans-Metanicotine, a subtype (alpha4beta2)-selective ligand for neuronal nicotinic acetylcholine receptor, is under clinical phase for Alzheimer's disease. An efficient synthetic route for (+/-)-methyl-(1-aryl-4-pyridin-3-yl-but-3-enyl)-amines, derivatives of trans-metanicotine, was explored. Allylation reaction of aryl aldimines with allylmagnesium bromide in THF gave (+/-)-methyl-(1-aryl-but-3-enyl)-amines. Protection of the amines with the Boc group and following Heck reaction of the N-Boc amines with 3-bromopyridine gave (+/-)-methyl-(1-aryl-4-pyridin-3-yl-but-3-enyl)-carbamic acid tert-butyl esters. Deprotection of the N-Boc group in aqueous 1N-HCI solution gave the titled amines in good yields. Thus, trans-metanicotine analogues modified at the a-position of the methylamino group with aryl groups were obtained in 5 steps.

Angelicastigmine (1), which belongs to the relatively seldom group of eserine alkaloids, was isolated as new alkaloid from the roots of Angelica polymorpha Maxim. The structure was elucidated by spectroscopic methods.

A convenient pathway for synthesis of trans-metanicotine analogues was developed. trans-Metanicotine, a subtype (alpha4beta2)-selective ligand for neuronal nicotinic acetylcholine receptor, is under clinical phase for Alzheimer's disease. Zn-mediated allylation of allyl bromide and acetaldehyde followed by Heck reaction with 3-bromopyridine gave 5-pyridin-3-yl-pent-4-en-3-ol (2). Tosylation of 5-pyridin-3-yl-pent-4-en-3-ol followed by substitution reaction with methylamine in sealed tube gave methyl-(1-methyl-4-pyridin-3-yl-but-3-enyl)-amine (4) in good yields. Thus, trans-metanicotine analogues modified at the alpha-position of the methylamino group with various functional groups can be obtained in 4 steps.

The cis- and trans-diastereomers of the 7,8-dihydro-7-deazapurine derivatives were synthesized from the corresponding diastereomers of 4-trans-cyano-2-methyl-3-phenyl-5-oxopyrrolidine (5), which were reduced from the 2-cis- and 2-trans-diastereomers of 4-trans-cyano-2-hydroxymethyl-3-phenyl-5-oxopyrrolidine (2) via tosylation, iodination and following elimination, respectively. The prepared cis- and trans-diastereomers of 6-amino-2-mercapto-8-methyl-7-phenyl-7,8-dihydro-7(9H)-deazapurine (8) were transferred to the corresponding 2-methylthio-diastereomers 9 and following desulfurization with Raney-nickel leaded to the cis- and trans-diastereomers of 6-amino-8-methyl-7-phenyl-7,8-dihydro-7(9H)-deazapurine (10), respectively. The synthesized 7-deazapurine derivatives were tested for their antibiotic activity by the serial two-fold dilution method.

Non-O1 vibrio cholerae infections are associated with sporadic cases of gastroenteritis and extraintestinal infections. Septicaemia due to non-O1 vibrio cholerae is rare and are mainly reported in adults, particularly in immunocompromised patients. We report a case of non-O1 vibrio cholerae septicaemia and gastroenteritis in an 8-year-old child. The patient presented with bloody diarrhoea, fever and severe dehydration. Non-O1 vibrio cholerae were isolated from blood and stool cultures. The clinical course was uneventful after starting appropriate rehydration and supportive therapy.

A female patient who presented with left empyema thoracis caused by Actinomyces odontolyticus is reported. She responded to treatment with penicillin and metronidazole but after 3 weeks developed leucopenia complicated by gram-negative septicaemia. Leucopenia improved rapidly on withdrawal of metronidazole. Treatment was continued with a prolonged course of penicillin and she made an uneventful recovery.

In order to evaluate the pharmacological activities of Chinese medicine, nine Umbelliferae plants were selected and their restoring activity against dexamethasone-induced disorders, liver protective activity, antimicrobial activity, anti-inflammatory activity and antimutagenic activity were tested and compared. Angelica dahurica. Angelica acutiloba and Ostericum koreanum showed various activities in these tests at the dose used in this study.

The purpose of this research was to develop new topical steroid derivatives showing reduced systemic effects. Pregna-16 alpha,17-carboxycyclic acetal derivatives have been recently synthesized by reacting triamcinolone with methyl acetylalkanoate in the presence of a catalytic amount of perchloric acid. In testing for the anti-inflammatory activity of the compounds, rat cotton-pellet granuloma inhibition bioassay and mouse croton-oil-induced ear oedema inhibition bioassay were employed. One of the synthesized compounds, (22R)-9 alpha-fluoro-11 beta,21-dihydroxy-3,20-dioxo-16 alpha, 17-(methyl, methoxycarbonylmethyl)methylenedioxy-1,4-pregnadiene (I), showed more or less the same activity as shown by prednisolone in the granuloma inhibition test. However, compound I showed higher activity in the ear oedema inhibition test when applied topically (ID50 = 0.002 mg), as compared to prednisolone (ID50 = 0.006 mg) and triamcinolone (ID50 = 0.026 mg). When compound I was applied to mice, and thymus involution was measured for judging systemic effects, it was found that compound I did not show any significant thymus involution up to 0.1 mg/mouse (systemic administration) and 0.5 mg/mouse (topical administration). Because of its significantly reduced systemic effects, this compound is a promising topical anti-inflammatory steroid.

A reinvestigation of the rhizomes of ATRACTYLIS KOREANA afforded in addition to 1,3-diacetoxytetradeca-6,12-diene-8,10-diyne reported previously (1) two new C (14)-polyacetylenes with an ene-diyn-ene-chromophor and one new C (14)-polyacetylene beside two known compounds with an ene-diyne-diene-chromophor. Their structures were established by spectroscopic and chemical methods.

Two new prenylflavonol glycosides epimedokoreanoside I ( 7) and epimedokoreanoside II ( 8) were isolated from EPIMEDIUM KOREANUM Nakai (Berberidaceae) beside five other known prenylflavonol glycosides with hypotensive activity. The structures were elucidated by spectroscopic and chemical methods.

An investigation of the rhizomes of ATRACTYLIS KOREANA afforded, in addition to known selinane sesquiterpenoids, an ester of tetradeca-6, 12-diene-8, 10-diyne-1,3-diol and two isomers of 6-methyl-2-geranyl- P-benzoquinone, which are new compounds for the genus Atractylis. Their structures were established by spectroscopic and chemical methods.