Preparation and characterization of high boiling solvent lignin-based polyurethane film with lignin as the only hydroxyl group provider

RSC Advances ◽  
2015 ◽  
Vol 5 (66) ◽  
pp. 53949-53955 ◽  
Author(s):  
Zhen Jia ◽  
Chunxiang Lu ◽  
Pucha Zhou ◽  
Lu Wang

High boiling solvent (HBS) lignin-based polyurethane film was successfully fabricated with lignin as the only hydroxyl group provider.

e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Toheed Akhter ◽  
Humaira Masood Siddiqi ◽  
Zareen Akhter ◽  
M. Saeed Butt

AbstractComposites from some novel polyimide and commercial epoxy were prepared aiming to improve the thermal behavior of epoxy resins. Two diamines namely 4-4'-diamino-4''-hydroxytriphenyl methane (DHTM) and 4-4'- diaminotriphenyl methane (DTM) were synthesized by reacting aniline and aldehydes according to a reported method. The synthesized diamines were blended with commercially available epoxy 1, 4-butanedioldiglycidylether (BDDE) to synthesize model epoxy amine networks which were compared with polyimideepoxy composites. The polyimides were synthesized by reaction of these diamines with aromatic anhydride namely 3,3',4,4'-benzophenone tetracarboxylic acid dianhydride (BTDA). These synthesized polyimides were dispersed in epoxy diamine networks to prepare composites. All the monomers and composites were characterized by making use of various analytical techniques including FTIR, NMR, TGA, DSC and XRD. Presence of hydroxyl group in the diamine helped in better dispersion of polyimide leading to high Tg and high char yield at 600 °C.


Author(s):  
Lingling Zhao ◽  
Zhenyang Zhao ◽  
Kaiyun Zhang ◽  
Xuan Zhang ◽  
Siqiong Xu ◽  
...  

Cotinine is a stable toxic contaminant, produced as a byproduct of smoking. It is of emerging concern due to its global distribution in aquatic environments. Microorganisms have the potential to degrade cotinine, however, the genetic mechanisms of this process are unknown. Nocardioides sp. strain JQ2195 is a pure culture strain that has been reported to degrade cotinine at micropollutant concentrations. This strain utilizes cotinine as its sole carbon and nitrogen source. In this study, a 50 kb gene cluster (designated as cot ) involved in cotinine degradation, was predicted based on genomic and transcriptomic analyses. A novel three-component cotinine hydroxylase gene (designated as cotA1A2A3 ), which initiated cotinine catabolism was identified and characterized. CotA from Shinella sp. HZN7 was heterologously expressed and purified, and shown to convert cotinine into 6-hydroxycotinine. H 2 18 O-labelling and ESI-MS analysis confirmed that the hydroxyl group incorporated into 6-hydroxycotinine was derived from water. This study provides new molecular insights into the microbial metabolism of heterocyclic chemical pollutants. IMPORTANCE In the human body, cotinine is the major metabolite of nicotine, and 10–15% of generated cotinine is excreted in urine. Cotinine is a structural analogue of nicotine and is much more stable than nicotine. Increased tobacco consumption has led to high environmental concentrations of cotinine, which may have detrimental effects on aquatic ecosystems and human health. Nocardioides sp. strain JQ2195 is a unique cotinine-degrading bacterium. However, the underlying genetic and biochemical foundations of cotinine degradation are still unknown. In this study, a 50 kb gene cluster (designated cot ) was identified by genomic and transcriptomic analyses as being involved in the degradation of cotinine. A novel three-component cotinine hydroxylase gene (designated cotA1A2A3 ) catalyzed cotinine to 6-hydroxy-cotinine. This study provides new molecular insights into the microbial degradation and enzymatic transformation of cotinine.


2018 ◽  
Vol 1 (1) ◽  
pp. 264-270
Author(s):  
Hady Wiraputra ◽  
Marline Nainggolan ◽  
Panal Sitorus

Tanaman buni (Antidesma bunius (L.) Spreng.) secara tradisional telah digunakan untuk hipertensi, takikardia, anemia, sifilis, antikanker, antioksidan, sumber pewarna alami dan antidiabetes. Saponin merupakan senyawa fitokimia yang mempunyai kemampuan membentuk busa dan mengandung aglikon polisiklik yang berikatan dengan satu atau lebih gula. Penelitian ini bertujuan untuk melakukan karakterisasi senyawa saponin hasil isolasi dari daun buni dengan spektrofotometer ultraviolet dan inframerah. Simplisia daun buni dilakukan karakterisasi kemudian diekstraksi dengan cara maserasi bertingkat menggunakan pelarut n-heksana dan etanol 80%. Selanjutnya ekstrak etanol dihidrolisis dengan HCl 2N kemudian difraksi dengan pelarut kloroform. Isolasi dilakukan terhadap fraksi kloroform dengan cara kromatografi lapis tipis preparatif menggunakan fase diam silika gel GF254 dan fase gerak yang sesuai. Isolat yang diperoleh diuji kemurnian dengan KLT 2 arah dan dikarakterisasi menggunakan spektrofotometer ultraviolet dan inframerah. Hasil pemeriksaan karakterisasi simplisia diperoleh kadar air 7,32%, kadar sari larut dalam etanol 52,70%, kadar sari larut dalam air 23,25%, kadar abu total 6,86% dan kadar abu tidak larut dalam asam 0,94%. Pemisahan fraksi kloroform dengan KLT menggunakan fase gerak n-heksana-etilasetat perbandingan 5:5 diperoleh noda 13 dan hasil KLT preparatif diperoleh 2 isolat murni yaitu isolat 1 (ungu merah) dengan Rf 0,92 dan isolat 2 (biru) dengan Rf 0,78. Hasil karakterisasi isolat 1 diperoleh panjang gelombang maksimum pada 208 nm dan dijumpai adanya gugus hidroksil, gugus -CH alifatis, ikatan C=C, gugus –CH2, gugus –CH3, dan gugus C-O. Hasil karakterisasi isolat 2 diperoleh panjang gelombang maksimum pada 204 nm dan adanya gugus hidroksil, gugus -CH alifatis, gugus –CH2, gugus –CH3, dan gugus C-O. Buni (Antidesmabunius (L.) Spreng.) has been traditionally used for the treatment of hypertension, tachycardia, anemia, syphilis, and used asanti-cancer, anti-oxidant, natural dye, and anti-diabetic. Saponin is a phytochemical compound which has capability in forming foam and contains polycyclic aglycone that binds with one or more glucose. This research aimed to conduct the characterization of saponin compound from buni leaves with ultraviolet spectrophotometer and infrared. Buni leaves simplicia was characterizedand extracted using sequential maceration method with n-hexane and 80% ethanol. The ethanol extract was hydrolyzed with HCl 2N and fractionized using chloroform solvent. Isolation of chloroform fraction was done using preparative thin-layer chromatography using silent phase of silica gel GF 254 and suitable mobile phase. Isolates obtained was taken into purity test with two dimensions thin-layer chromatography and characterized using ultraviolet spectrophotometer and infrared. The characterized simplicia resulted with 7.32% of water content, 52.70% of dissolved content in ethanol, 23.25% of dissolvedcontent in water, 6.86% of total ash content, and 0.94% of undissolved ash content in acid. Fractinationof chloroform fraction with thin-layer chromatography using mobile phase ofn-hexane-ethyl acetate with 5:5 ration resulted with 13 spotsand the result of the preparative thin-layer chromatography resulted 2 pure isolates which are isolate 1 (purple-red) with Rf 0.92 and isolate 2 (blue) with Rf 0.78. The characterization of isolate 1 resulted that the maximum wave lengthwas 208 nm with hydroxyl group, –CH aliphatic group, C=C bond, –CH2 group, –CH3 group, and C–O group. The characterization of isolate 2 resulted that the maximum wave lengthwas204 nm with hydroxyl group, –CH aliphatic group, –CH2 group, –CH3 group, and C–O group.


Author(s):  
Oun D. Khudair ◽  
Diar A. Fatih

Abstract       The target derivative are gentamicin linked with L-Val- L-Ala by an ester linkage. These were synthesized by esterification method, which included the reaction of -OH hydroxyl group on (carbon No.5) of gentamicin with the acid chloride of the corresponding dipeptide, The preparation of new derivative of gentamicin involved protected the primary & secondary amine groups of Gentamicin, by Ethylchloroformate (ECF) to give N-carbomethoxy Gentamicin which was used for further chemical synthesis involving the free hydroxyl groups. Then prepared dipeptide (L-Val- L-Ala) by conventional solution method in present DCC & HoBt then reacted with thionyl chloride to prepared acid chloride of dipeptides, then after, linked by ester linkage to N-protection gentamicin in present pyridine as base, finally deportation the amino group of synthesized compound by using TFAA in present anisole. The characterization of the titled compounds were performed utilizing FTIR spectroscopy, CHNS elemental analysis, and by measurements of their physical properties.  


Author(s):  
Sudha Sri Kesavan S ◽  
Usha Nandhini S ◽  
Girija Vasudevan

Objectives: A potent Streptomyces strain isolated from garden soil samples of Sathyabama University, Chennai, and the characterization and its antimicrobial activity was reported previously. This report deals with partial purification and characterization of the partially purified antimicrobial compound by liquid chromatography-mass spectrum (LC-MS) method.Method: The crude extract was characterized by ultra violet-visible spectrum (UV) and Fourier transform infrared spectroscopy (FTIR) subsequently partial purification was done by thin-layer chromatography, and the bands were used for LC-MS analysis. The obtained mass spectrum was searched in NIST for species data by molecular weight. The compound was identified by comparing the mass spectrum with the known compounds mass spectrum having 98-100% identical. The biological activity of the identified compound was searched in PubChem.Results: The UV and FTIR spectrum indicate the presence of hydroxyl group, aliphatic chain, aromatic, aliphatic amines, and ethers in the crude extract. The LC-MS spectrum revealed the presence of 12 compounds in high intensity resembling antimicrobial compounds such as imidazole, N-trifluoroacetyl, cyclohexane, 2-nitro, and stigmasterol.Conclusion: The instrumental analysis shows the presence of 14 different compounds, and PubChem compound search shows these compounds having various biological activities including antibacterial, antifungal, anticancer, antitumor, and antidepressant. This report insists us further to evaluate the anticancer, antitumor, and antitrypanosomal activities of the partially purified compound.


2012 ◽  
Vol 476-478 ◽  
pp. 2055-2058 ◽  
Author(s):  
Zhi Hua Lu ◽  
Dong Mei Zhao ◽  
Kang Ning Sun

In this study, a genipin cross linked scaffold containing nano-hydroxyapatite (n-HAp) and carboxymehthyl chitosan (CMCS) was developed by freeze drying technique. The scaffolds were characterized using FTIR, XRD and SEM. The cytotoxicity of the scaffolds was compared with scaffolds cross linked by glutaraldehyde, and the Young’s modulus was also tested. FTIR and XRD results indicated that CMCS’s hydroxyl group, amino and amide regulated the n-HAp crystallization process, which results in the nano homogenous distribution of n-HAp and provided nano topographical features for nanohybrid scaffolds. SEM images revealed the scaffolds had porous structure and the pores were interconnected with an average diameter of 150 μm, which was profit for the growth of tissues. Cell morphology showed the genipin cross linked scaffolds had less toxicity and more facility for adhesion and proliferation of cells. Great mechanical properties of the scaffolds indicate their potential use in bone tissue engineering.


1974 ◽  
Vol 137 (2) ◽  
pp. 263-272 ◽  
Author(s):  
John K. Findlay ◽  
Lothar Siekmann ◽  
Heinz Breuer

1. 18-Hydroxyoestrone was reduced by NaBH4 in methanol, giving 18-hydroxyoestradiol-17α and 18-hydroxyoestradiol-17β in the ratio 3:7. 2. Treatment of 18-hydroxyoestrone with a strong alkali yielded 18-noroestrone; however, the 18-hydroxyoestradiols did not undergo transformation to their respective 18-nor derivatives. 3. All the 18-hydroxylated oestrogens were stable under acid conditions. They formed Kober chromogens: the chromogenicity of 18-hydroxyoestrone was only one-third that of the 18-hydroxyoestradiols and oestriol. 4. Paper-, thin-layer- and gas–liquid-chromatographic systems for the characterization of these compounds are described. 5. An examination of the mass spectra revealed peaks characteristic of the substituted carbon atoms. Definite assignment of the 17α- and 17β-hydroxyl groups of the epimeric 18-hydroxyoestrogens was possible by characteristic fragmentation of the free steroids. Further, the configuration of 18-hydroxyoestradiol-17β was confirmed by the formation of the dimethylsildioxy derivative of the 3-methylether of the steroid. 6. Both rat and rabbit liver slices reduced 18-hydroxyoestrone to 18-hydroxyoestradiol-17β and some other labile, polar metabolites with properties similar to 2-hydroxylated oestrogens. No formation of 18-hydroxyoestradiol-17α in vitro was observed. 7. The results are discussed with respect to the possible influence of the 18-hydroxyl group on reactions at C-17, as well as the reactions of 18-hydroxylated oestrogens with strong acid (Kober reactions) and alkali.


2012 ◽  
Vol 9 (3) ◽  
pp. 1613-1622 ◽  
Author(s):  
Farouq E. Hawaiz ◽  
Mohammad K. Samad

A number of 3-[4-(benzyloxy)-3-(2-Chlorophenylazo)-phenyl]-5-(substituted-phenyl)-1-substituted-2-pyrazolines( 4a-j) and (5a-j) have been synthesized by diazotization of 2-chloroaniline and its coupling reaction with 4-hydroxy acetophenone, followed by benzyloxation of the hydroxyl group to give the substrate [4-benzyloxy-3-(2-chlorophenylazo)-acetophenone (1)].The prepared starting material (1) has been reacted with different substituted benzaldehydes to give a new series of chalcone derivatives 1-[(4-benzyloxy)-3-(2-chloro-phenylazo)-phenyl]-3-(substituted phenyl)-2-propen-1-one (3a-j), in high yields and in a few minutes, and the later compounds were treated with hydrazine hydrate according to Michael addition reaction to afford a new biolological active target compounds (4a-j) and (5a-j). Furthermore, The structures of the newly synthesized compounds were confirmed by FT-IR,13C-NMR,13C-DEPT &1H-NMR spectral data. The chalcone and pyrazoline derivatives were evaluated for their anti bacterial activity againstEscherichia colias gram negative andStaphylococcus aureusas gram positive, the results showed significant activity against both types of bacteria.


2011 ◽  
Vol 990 (1-3) ◽  
pp. 209-216 ◽  
Author(s):  
Jasmina Lapić ◽  
Alma Pezerović ◽  
Mario Cetina ◽  
Senka Djaković ◽  
Vladimir Rapić

FLORESTA ◽  
2021 ◽  
Vol 51 (4) ◽  
pp. 893
Author(s):  
Thiago Cardoso Silva ◽  
Rafael Leite Braz ◽  
Emmanoella Costa Guaraná Araujo ◽  
Gisely Alves da Silva ◽  
Maria de Los Angeles Perez Fernandez Palha

This study aimed to chemically characterize the bark extracts from three tree species: Anacardium occidentale L., Ziziphus joazeiro Mart. and Mimosa caesalpiniaefolia Benth., in addition to obtaining the soluble extract content in water, alcohol and hexane from the bark of these species. The bark was collected from branches of the three species and subsequently pre-dried and milled. The extract content was then determined using the Sohxlet method aiming to quantify the total extractives in the samples, and determine the extract content soluble in water, ethyl alcohol and hexane. The extracts were further analyzed by Near Infrared Spectroscopy (NIRS) analysis to determine their chemical composition. The extract contents in the three species behaved in a similar way, with hexane being the solvent which extracted more compounds and juazeiro the species that displayed the highest total extract content. With the chemical characterization of the extracts, it was possible to identify the presence of functional groups characteristic of carbohydrates and proteins in the aqueous extracts; the presence of characteristic hydroxyl group, for example in alcohols, aldehydes, ketones and ethers in the ethanolic extracts; and the presence of fatty acids and aromatic compounds (essential oils) in hexanolic extracts. The essential oils were the compounds which presented larger quantities, and can be exploited by the pharmaco-chemical industry.


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