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1.
Braz. j. microbiol ; 49(supl.1): 64-67, 2018. tab
Article Dans Anglais | LILACS | ID: biblio-1039270

Résumé

Abstract The aim of this research was to evaluate the efficiency of aqueous alkali-treated Brachiaria straw for the cultivation of appropriate species of oyster mushroom. The substrate used in the cultivation of various Pleurotus spp. was soaked for 20 min by using two different procedures: (i) 0.5-2.0% Ca(OH)2 in 100 L water, and (ii) 50-250 L water. As a result, 1% Ca(OH)2 dissolved in 100 L water and 3.5 kg of Brachiaria straw presented the best production. The most suitable species for the application of the present method were P. pulmonarius and P. sapidus. The success of this technique is directly related to the concentration of Ca(OH)2 and water, the species, and the origin and quality of raw material used as the substrate in the production of oyster mushroom.


Sujets)
Pleurotus/croissance et développement , Milieux de culture/composition chimique , Brachiaria/composition chimique , Production végétale/méthodes , Dépollution biologique de l'environnement , Tiges de plante/métabolisme , Tiges de plante/microbiologie , Tiges de plante/composition chimique , Pleurotus/métabolisme , Milieux de culture/métabolisme , Brachiaria/métabolisme , Brachiaria/microbiologie , Production végétale/instrumentation , Hydrolyse
2.
Braz. j. microbiol ; 48(3): 410-418, July-Sept. 2017. tab, graf
Article Dans Anglais | LILACS | ID: biblio-889127

Résumé

Abstract Chaetoglobosin A is an antibacterial compound produced by Chaetomium globosum, with potential application as a biopesticide and cancer treatment drug. The aim of this study was to evaluate the feasibility of utilizing cornstalks to produce chaetoglobosin A by C. globosum W7 in solid-batch fermentation and to determine an optimal method for purification of the products. The output of chaetoglobosin A from the cornstalks was 0.34 mg/g, and its content in the crude extract was 4.80%. Purification conditions were optimized to increase the content of chaetoglobosin A in the crude extract, including the extract solvent, temperature, and pH value. The optimum process conditions were found to be acetone as the extractant, under room temperature, and at a pH value of 13. Under these conditions, a production process of the antifungal chaetoglobosin A was established, and the content reached 19.17%. Through further verification, cornstalks could replace crops for the production of chaetoglobosin A using this new production process. Moreover, the purified products showed great inhibition against Rhizoctonia solani, with chaetoglobosin A confirmed as the main effective constituent (IC50 = 3.88 µg/mL). Collectively, these results demonstrate the feasibility of using cornstalks to synthesize chaetoglobosin A and that the production process established in this study was effective.


Sujets)
Microbiologie industrielle/méthodes , Callosités/microbiologie , Chaetomium/métabolisme , Alcaloïdes indoliques/métabolisme , Antifongiques/métabolisme , Déchets/analyse , Microbiologie industrielle/instrumentation , Callosités/métabolisme , Structure moléculaire , Tiges de plante/métabolisme , Tiges de plante/microbiologie , Alcaloïdes indoliques/isolement et purification , Alcaloïdes indoliques/composition chimique , Antifongiques/isolement et purification , Antifongiques/composition chimique
3.
Braz. j. microbiol ; 47(2): 489-496, Apr.-June 2016. tab, graf
Article Dans Anglais | LILACS | ID: lil-780830

Résumé

Abstract Sugarcane straw has become an available lignocellulosic biomass since the progressive introduction of the non-burning harvest in Brazil. Besides keeping this biomass in the field, it can be used as a feedstock in thermochemical or biochemical conversion processes. This makes feasible its incorporation in a biorefinery, whose economic profitability could be supported by integrated production of low-value biofuels and high-value chemicals, e.g., xylitol, which has important industrial and clinical applications. Herein, biotechnological production of xylitol is presented as a possible route for the valorization of sugarcane straw and its incorporation in a biorefinery. Nutritional supplementation of the sugarcane straw hemicellulosic hydrolyzate as a function of initial oxygen availability was studied in batch fermentation of Candida guilliermondii FTI 20037. The nutritional supplementation conditions evaluated were: no supplementation; supplementation with (NH4)2SO4, and full supplementation with (NH4)2SO4, rice bran extract and CaCl2·2H2O. Experiments were performed at pH 5.5, 30 °C, 200 rpm, for 48 h in 125 mL Erlenmeyer flasks containing either 25 or 50 mL of medium in order to vary initial oxygen availability. Without supplementation, complete consumption of glucose and partial consumption of xylose were observed. In this condition the maximum xylitol yield (0.67 g g-1) was obtained under reduced initial oxygen availability. Nutritional supplementation increased xylose consumption and xylitol production by up to 200% and 240%, respectively. The maximum xylitol volumetric productivity (0.34 g L-1 h-1) was reached at full supplementation and increased initial oxygen availability. The results demonstrated a combined effect of nutritional supplementation and initial oxygen availability on xylitol production from sugarcane straw hemicellulosic hydrolyzate.


Sujets)
Xylitol/biosynthèse , Candida/métabolisme , Saccharum/microbiologie , Xylose/métabolisme , Tiges de plante/métabolisme , Tiges de plante/microbiologie , Tiges de plante/composition chimique , Milieux de culture/métabolisme , Saccharum/métabolisme , Saccharum/composition chimique , Fermentation , Hydrolyse
4.
Braz. j. microbiol ; 45(4): 1179-1186, Oct.-Dec. 2014. graf, tab
Article Dans Anglais | LILACS | ID: lil-741267

Résumé

Two mesophilic streptomycetes (S. violaceoruber and S. spiroverticillatus) were selected to study their Poly R-478 decolorization ability and lignocellulose solubilizing activity. Both strains were able to degrade Poly R-478 dye and ferulic acid during growth on a minimal salts medium. The Poly R-478 decolorizing activities of both strains were induced by adding different carbon sources to the culture media. S. violaceoruber could decolorize 63% of Poly R-478 after 24 h. Both strains could solubilize straw and produce acid-precipitable polymeric lignin (APPL) with different efficiency. From the major extracellular enzymes recovery of both strains on rice and wheat straw, we can predicate that the biodegradation process was partial indicating a possible utilization in biological delignification.


Sujets)
Anthraquinones/métabolisme , Lignine/métabolisme , Polymères/métabolisme , Streptomyces/métabolisme , Biotransformation , Acides coumariques/métabolisme , Milieux de culture/composition chimique , Oryza/métabolisme , Tiges de plante/métabolisme , Streptomyces/croissance et développement , Triticum/métabolisme
5.
Indian J Exp Biol ; 2014 Nov; 52(11): 1122-1127
Article Dans Anglais | IMSEAR | ID: sea-153802

Résumé

The medicinal plant Plumbago contains a very potent secondary metabolite, plumbagin having many therapeutic properties. Callus culture was induced using explants, leaf, stem and shoot apex, from P. auriculata. Murashige and Skoog media fortified with various growth hormones like NAA, IAA, IBA and 2, 4-D individually and in various combinations were checked for callus induction. Among the growth hormones used, 1 mg/L 2, 4-D showed best callusing. The hormonal combinations of 1 mg/L IAA and 1.5 mg/L NAA in the media exhibited best callus induction using stem internode as an explant. Plumbagin content from root, stem, leaf and callus was analyzed by using thin layer chromatographic technique. The callus derived from stem showed comparable plumbagin content to the in vivo plant parts. Quantitative spectrophotometric analysis of plumbagin from plant samples and callus indicated that plumbagin content was maximum in roots which was followed by callus, stem and leaf samples respectively. Generation of in vitro sources for plumbagin, for therapeutic applications will serve as a continuous supply and will contribute to preserve the natural plant recourses.


Sujets)
Chromatographie sur couche mince , Colorimétrie , Cytokinine/pharmacologie , Acides indolacétiques/pharmacologie , Naphtoquinones/analyse , Naphtoquinones/métabolisme , Spécificité d'organe , Organoïdes/effets des médicaments et des substances chimiques , Cellules végétales/effets des médicaments et des substances chimiques , Feuilles de plante/métabolisme , Racines de plante/métabolisme , Pousses de plante/métabolisme , Tiges de plante/métabolisme , Plantes médicinales/croissance et développement , Plantes médicinales/métabolisme , Plumbaginaceae/croissance et développement , Plumbaginaceae/métabolisme , Techniques de culture de tissus
6.
Braz. j. microbiol ; 45(3): 885-892, July-Sept. 2014. ilus, graf, tab
Article Dans Anglais | LILACS | ID: lil-727017

Résumé

India is amongst the largest banana (Musa acuminata) producing countries and thus banana pseudo stem is commonly available agricultural waste to be used as lignocellulosic substrate. Present study focuses on exploitation of banana pseudo stem as a source for bioethanol production from the sugars released due to different chemical and biological pretreatments. Two fungal strains Aspergillus ellipticus and Aspergillus fumigatus reported to be producing cellulolytic enzymes on sugarcane bagasse were used under co-culture fermentation on banana pseudo stem to degrade holocellulose and facilitate maximum release of reducing sugars. The hydrolysate obtained after alkali and microbial treatments was fermented by Saccharomyces cerevisiae NCIM 3570 to produce ethanol. Fermentation of cellulosic hydrolysate (4.1 g%) gave maximum ethanol (17.1 g/L) with yield (84%) and productivity (0.024 g%/h) after 72 h. Some critical aspects of fungal pretreatment for saccharification of cellulosic substrate using A. ellipticus and A. fumigatus for ethanol production by S. cerevisiae NCIM 3570 have been explored in this study. It was observed that pretreated banana pseudo stem can be economically utilized as a cheaper substrate for ethanol production.


Sujets)
Aspergillus/métabolisme , Biocarburants , Éthanol/métabolisme , Déchets industriels , Musa/métabolisme , Tiges de plante/métabolisme , Saccharomyces cerevisiae/métabolisme , Aspergillus/croissance et développement , Inde , Saccharomyces cerevisiae/croissance et développement
7.
Braz. j. microbiol ; 45(2): 457-465, Apr.-June 2014. graf, tab
Article Dans Anglais | LILACS | ID: lil-723100

Résumé

The main objective of this study was production of ethanol from three lignocellulosic biomasses like sugarcane bagasse, rice straw and wheat straw by Sacchromyces cervisae. All the three substrates were ground to powder form (2 mm) and pretreated with 3%H2O2 + 2% NaOH followed by steaming at 130 °C for 60 min. These substrates were hydrolyzed by commercial cellulase enzyme. The whole fermentation process was carried out in 500 mL Erlenmeyer flask under anaerobic conditions in submerged fermentation at 30 °C for three days of incubation period. FTIR analysis of the substrates indicated significant changes in the alteration of the structure occurred after pretreatment which leads to efficient saccharification. After pretreatment the substrates were hydrolyzed by commercial cellulase enzyme and maximum hydrolysis was observed in sugarcane bagasse (64%) followed by rice straw (40%) and wheat straw (34%). Among all these tested substrates, sugarcane bagasse (77 g/L) produced more ethanol as compared to rice straw (62 g/L) and wheat straw (44 g/L) using medium composition of (%) 0.25 (NH4)2SO4, 0.1 KH2PO4, 0.05 MgSO4, 0.25 Yeast extract by S. cervisae.


Sujets)
Éthanol/métabolisme , Saccharomyces cerevisiae/croissance et développement , Saccharomyces cerevisiae/métabolisme , Anaérobiose , Agriculture/méthodes , Cellulose , Fermentation , Oryza/métabolisme , Tiges de plante/métabolisme , Saccharum/métabolisme , Température , Triticum/métabolisme , Déchets
8.
Biol. Res ; 47: 1-7, 2014. graf, tab
Article Dans Anglais | LILACS | ID: biblio-950715

Résumé

BACKGROUND: Effect of chlorocholine chloride (CCC) on phenolic acids composition and polyphenols accumulation in various anatomical parts (stems, leaves and inflorescences) of common buckwheat (Fagopyrum esculentum Moench) in the early stages of vegetation period were surveyed. RESULTS: Treatment of buckwheat seeds with 2% of CCC has been increased content of total phenolics in the stems, leaves and inflorescences. On analyzing the different parts of buckwheat plants, 9 different phenolic acids - vanilic acid, ferulic acid, trans-ferulic acid, chlorogenic acid, salycilic acid, cinamic acid, p-coumaric acid, p-anisic acid, methoxycinamic acid and catechins were identified. The levels of identified phenolic acids varied not only significantly among the plant organs but also between early stages of vegetation period. Same changes as in contents of chlorogenic acid, ferulic acid, trans-ferulic acid were found for content of salycilic acid. The content of these phenolic acids has been significant increased under effect of 2% CCC treatment at the phase I (formation of buds) in the stems and at the phase II (beginning of flowering) in the leaves and then inflorescences respectively. The content of catechins as potential buckwheat antioxidants has been increased at the early stages of vegetation period after treatment with 2% CCC. CONCLUSIONS: The obtained results suggest that influence of CCC on the phenolics composition can be a result of various mechanisms of CCC uptake, transforming and/or its translocation in the buckwheat seedlings.


Sujets)
Chlorméquat/pharmacologie , Fagopyrum/effets des médicaments et des substances chimiques , Polyphénols/biosynthèse , Hydroxybenzoates/métabolisme , Propionates , Graines/effets des médicaments et des substances chimiques , Graines/métabolisme , Catéchine/analyse , Acide chlorogénique/analyse , Chromatographie en phase liquide à haute performance , Composés du tungstène , Tiges de plante/effets des médicaments et des substances chimiques , Tiges de plante/métabolisme , Feuilles de plante/effets des médicaments et des substances chimiques , Feuilles de plante/métabolisme , Fagopyrum/croissance et développement , Fagopyrum/métabolisme , Acides coumariques/analyse , Inflorescence/effets des médicaments et des substances chimiques , Inflorescence/métabolisme , Éthers d'hydroxybenzoate/analyse , Hydroxybenzoates/composition chimique , Molybdène , Antioxydants/analyse , Antioxydants/métabolisme
9.
Article Dans Anglais | IMSEAR | ID: sea-19164

Résumé

BACKGROUND & OBJECTIVE: Tunisian Chrysanthemum species are known to have medicinal activity and some of the species are used in traditional medicine. We have earlier shown the use of C. trifurcatum flowerheads in Tunisian traditional medicine to treat constipation. In the present study we investigated the anti microbiol activity of four Tunision Chrysanthemum species. METHODS: Different parts (flowers, leaves, stems, roots, leaves and flowers and leaves and stems) of four Tunisian Chrysanthemum species, were extracted with solvents of increasing polarity to obtain aqueous and organic extracts. These extracts were tested in vitro for their antimicrobial activity against 14 bacteria and four yeasts, using agar diffusion and microdilution methods. Activity was evaluated by measuring the zones of inhibition against the tested organisms and minimum inhibitory concentrations (MIC) were determined from the lowest concentrations of extracts to inhibit the growth of microorganisms. Cytotoxity and antiviral activities against Herpes simplex virus type 1 (HSV-1), were evaluated using the neutral red incorporation method. RESULTS: Extracts of the 4 Chrysanthemum species showed some degree of activity against one or more of the microbial strains with MIC ranging from 0.625 to 1.25 mg/ml. Most of the extracts were well tolerated by Vero cells with CC(50) > 500 microg/ml. The petroleum ether extract of C. trifurcatum stems and leaves protected infected cells with EC(50) of 100 microg/ml. INTERPRETATION & CONCLUSION: Our findings showed that some Chrysanthemum extracts exhibited antimicrobial and/or anti-HSV-1 activities. Further studies aimed to the isolation and identification of active substances from the extracts which exhibited interest activities, need to be done.


Sujets)
Animaux , Anti-infectieux/pharmacologie , Chlorocebus aethiops , Chimie pharmaceutique/méthodes , Chrysanthemum/métabolisme , Fleurs/métabolisme , Médecine traditionnelle , Tests de sensibilité microbienne , Phytothérapie/méthodes , Extraits de plantes/pharmacologie , Racines de plante/métabolisme , Tiges de plante/métabolisme , Tunisie , Cellules Vero
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