► Xanthan gum was produced by Xanthomonas campestris pv. campestris NRRL B-1459. ► The components used were sucrose, Brewer's yeast; and NH4NO3. ► Xanthan gum was produce with the desired molecular ...weight and total sugar content. ► The xanthan gum was also evaluated using Proton Nuclear Magnetic Resonance (1H NMR).
Xanthan gum was produced by Xanthomonas campestris pv. campestris NRRL B-1459 using diluted sugar cane broth in experiments that lasted 24h. The components used were in g/L: 27.0 sucrose; 2.0 Brewer's yeast; and 0.8 NH4NO3. The mixture was fermented at 750rpm and 0.35vvm. These conditions produced xanthan gum with the desired molecular weight and total sugar content, which were 4.2×106Da and 85.3%, respectively. The sugar consisted of 43% glucose, 32% mannose and 24% glucuronic acid in a 1.79:1.33:1 ratio. The xanthan gum produced by this method was confirmed by comparing the infrared spectrum of commercial xanthan gum with the infrared spectrum of the xanthan gum produced using this method. The infrared spectra were very similar, which confirmed the identity the xanthan gum produced using our method. The xanthan gum was also evaluated using Proton Nuclear Magnetic Resonance (1H NMR).
Display omitted
•Antioxidant activity of the extract and fractions from leaves of Cassia bakeriana.•Inhibition of α-amylase activity of the ethanolic extract.•Inhibition of glycation of the ...dichloromethane and ethyl acetate fractions.•Identification of compounds by liquid chromatography coupled to mass spectrometry.•Extracts and fractions showed low cytotoxicity against Vero cells.
The prevalence of diabetes has increased rapidly in the world. Chronic hyperglycemia is associated with the complications of diabetes and is a major problem for medicine. The present study aimed to explore the antidiabetic potential of the leaves of Cassia bakeriana Craib (family Leguminosae) by evaluating the antioxidant activity and inhibition of α-amylase, α-glucosidase, lipase and glycation activities, in addition to determining the chemical constituents of the most active fractions. Therefore, the n-hexane extract (HE) and the ethanolic extract (EE) of the leaves were prepared by maceration, and the fractions were obtained by liquid-liquid extraction. The EE of C. bakeriana and its fractions showed high antioxidant activity in the oxygen radical absorbance capacity (ORAC) assay, being superior to the positive control (ascorbic acid). In the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, the n-butanol fraction (BF) and ethyl acetate fraction (EAF) presented the best results. The EE showed higher inhibition of α-amylase activity (IC50 = 5.00 ± 0.85 μg mL−1) followed by EAF and BF. DF was the most active in the inhibition of α-glucosidase activity (IC50 = 359.55 ± 2.90 μg mL−1). The HE showed high inhibition of pancreatic lipase activity (IC50 = 25.27 ± 8.78 μg mL−1) and dichloromethane fraction (DF) and EAF were the most active inhibitors of glycation (IC50 = 37.85 ± 0.49 and 53.25 ± 11.24 μg mL−1, respectively). The fractionation of DF by semi-preparative HPLC-DAD led to the isolation of flavonoids: kaempferol-3-O-rhamnoside (I) and kaempferol (II), which were characterized by NMR and HPLC-ESI-MS. These compounds showed antioxidant activity in the ORAC method, but only compound II was active in the DPPH method. The isolated kaempferol (II) showed inhibitory activity against α-amylase (IC50 = 1.5 ± 0.14 μg mL−1). The compounds I and II showed inhibition of glycation (IC50 = 84.27 ± 11.38 and 64.16 ± 1.53 μg mL−1, respectively). Through the HPLC-ESI-MS analysis of the EE, DF and EAF, it was possible to propose the identification of some compounds such as acid phenolics, flavonoids, megastigmane, fatty acids and derivatives, sphingolipids, proanthocyanidins, cyanidin and anthraquinone.
Pereskia aculeata Mill., popularly known in Brazil as “Ora-pro-nobis”, is an unconventional edible vegetable. Taking into account its potential for agronomic cultivation, this study aimed to evaluate ...the growth response of this plant under intermittent drought through controlled reductions in the substrate matric potential, in a greenhouse. Treatments consisted of adding to the pots a volume of water to raise the matric potential to -5 kPa, according to the water retention curve in the substrate, whenever the mean substrate matric potential reached values between -10 kPa and -70 kPa, depending on the treatment. At 140 days after transplanting, leaf area and dry mass of leaves, stems and roots were determined. The intermittent reduction of the matric potential in the root zone of “Ora-pro-nobis” affected less the dry mass accumulation in leaves (reduction of 21.4%) than in stems (reduction of 48.1%) and roots (reduction of 63.7%), and that is interesting because leaves are the main commercial product of this plant. The treatment also modified the proportionality of dry mass allocation among plant parts and reduced the photosynthetic efficiency of leaves, fact evidenced by the linear increase of the specific leaf area (0.63 cm2 g-1kPa-1) and leaf area ratio (0.39 cm-2 g-1kPa-1), although not affecting directly the leaf area.
“Ora-pro-nobis” (Pereskia aculeata Mill.) é uma hortaliça não convencional, no Brasil. Levando-se em conta seu potencial para o cultivo agronômico, objetivou-se avaliar a resposta dessa planta ao défice hídrico intermitente por redução controlada no potencial matricial do substrato, em casa-de-vegetação. Os tratamentos consistiram na aplicação de volumes de água aos vasos, calculados para elevar o potencial mátrico a -5 kPa, com base na curva de retenção de água do substrato, toda vez que a média do potencial mátrico atingisse de -10 kPa a -70 kPa, dependendo do tratamento. Aos 140 dias após o transplantio, foram avaliadas a área foliar e as massas secas de folhas, caules e raízes. A redução intermitente do potencial mátrico na zona radicular de “Ora-pro-nobis” afetou menos a acumulação de massa seca nas folhas (redução de 21,4%) do que nos caules (redução de 48,1%) e nas raízes (redução de 63,7%), o que é interessante, já que as folhas são o principal produto comercial dessa planta. O tratamento também modificou a proporcionalidade de alocação de massa seca entre as partes da planta e reduziu a eficiência fotossintética das folhas, evidenciada pelo aumento linear da área foliar específica (0,63 cm2 g-1 kPa-1) e da razão de área foliar (0,39 cm2 g-1 kPa-1), mas não afetou diretamente a área foliar.
The antimicrobial and cytotoxic activities of the leaf or flower ethanol extracts from Senna and Cassia species.
Display omitted
•Species belonging to the genera Senna or Cassia are widely used in ...Brazilian traditional medicine.•The antimicrobial and cytotoxic activities of the leaf or flower ethanol extracts from Senna and Cassia species were evaluated.•S. macranthera flower ethanol extract exerted significant antifungal activity that was correlated with a series of phenolic compounds.
In Brazilian traditional medicine, botanical species belonging to the genera Senna and Cassia are widely used as laxative, analgesic, and antifungal agents to treat ringworm and other fungal skin infections. This has motivated us to select and to screen ten species of these genera for their antibacterial, antifungal, and cytotoxic activities. The leaf or flower ethanol extracts were investigated against aerobic and anaerobic oral bacteria and Candida spp.; the microdilution broth method was employed. Cytotoxicity was determined against Vero cells. Among the plant extracts evaluated herein, four extracts at 200.0–400.0 μg mL–1 presented moderate activities against at least two bacterial strains. Concerning the antifungal action, the S. macranthera flower ethanol extract exerted significant antifungal effect with MIC values ranging from 5.9 to 23.4 μg mL–1. This extract was submitted to liquid-liquid extraction, and the resulting fractions were tested. The ethyl acetate fraction showed better antifungal activity (MIC values of 5.9 μg mL–1 for C. glabrata and 23.4 μg mL–1 for C. albicans and C. tropicalis) as compared with amphotericin B (0.1–0.2 μg mL–1), used as positive control. The bioactive metabolites of this fraction were identified by UHPLC–ESI/HRMS/MSn, which revealed the presence of eighteen compounds, including one organic acid (1), two flavan-3-ol (2 and 3), one flavone (4), two glycosylated flavonols (5 and 6), five proanthocyanidin dimers (7–11b), and seven proanthocyanidin trimers (12–18). The antimicrobial activities of some Senna or Cassia species studied here have been reported for the first time. The present results show that S. macranthera flowers are an interesting source of new antifungal agents.
•LC-ESI-MS/MS analysis identified various proanthocyanidins in K. coriacea inner bark.•Liquid fractionation increased polyphenols in the polar fractions.•n-Butanol fraction showed high antioxidant ...capacity and low cytotoxicity.•Lipid peroxidation and glycation inhibited by ethyl acetate and n-butanol fractions.•The repertoire of bioactive compounds inhibited α-amylase and pancreatic lipase.
Display omitted
Chronic hyperglycemia and hyperlipidemia are associated with excessive formation of reactive oxygen species and advanced glycation end-products. The present study aimed to evaluate the potential in vitro antidiabetic properties of Kielmeyera coriacea inner bark. The main phytochemical compounds were identified by UHPLC-ESI/MSn and the ethanol extract and its fractions were used to evaluate their antioxidant and anti-glycation capacities, as well as their inhibitory potential against glycoside and lipid hydrolases activities. The polar fractions, especially the n-butanol fraction, had free radical scavenging and quenching properties (ORAC and FRAP values>1800 and 1000 µmol trolox eq/g, respectively, and DPPH IC50<4 µg/mL), and inhibited ROS production (p < 0.01), lipid peroxidation (p < 0.001), glycation (IC50 ~ 10 µg/mL in the BSA-fructose assay; IC50 ~ 200 µg/mL in the BSA-methylglyoxal and arginine-methylglyoxal assays), α-amylase (IC50<0.1 µg/mL) and lipase (IC50<5 µg/mL), with no cytotoxicity. Biomolecules well-known as potent antioxidants were identified for the first time in the inner bark of K. coriacea, such as protocatechuic acid, epicatechin and procyanidins A, B and C. Together, our results support the antioxidant, anti-glycation and glycoside and lipid hydrolases inhibitory properties of the inner bark of K. coriacea, a species found in the Brazilian savanna, which makes it especially useful to combat oxidative stress and hyperglycemia and hyperlipidemia.
Soy production in Brazil is an important factor for the agro-industrial, economic, and social development of the country. The expansion of soy in the Brazilian territory is mainly due to the ...incorporation of new genetic characteristics into cultivars that granted resistance to the Cerrado conditions and to herbicides. Currently, Brazilian soy production is the result of genetically modified cultivars. Studies regarding the chemical composition of soybeans show that qualitative and quantitative variations can occur, depending on the region of production. This work aimed to investigate the chemical composition of soybeans produced in different cities of the Triângulo Mineiro region/MG, Brazil (Harvest 2017/2018) and stored in three warehouses located in the city of Uberaba/MG. The grain analysis was made by liquid chromatography coupled to electrospray ionization mass spectrometry (LC-MS-ESI). The classes of metabolites identified from methanolic extraction were organic acids, phenolic compounds, flavonoids, sugars, amino acids, dipeptides, nitrogenous bases, nucleosides, sphingolipids, and fatty acids. The isoflavones genistein, daidzein, glycitein, genistin, acetyldaidzin, and acetylgenistin were identified in soybeans from the three warehouses. The flavonoid eriodictyol-O-hexoside was also found. The Principal Component Analysis (PCA) from the mass spectrum data obtained by direct injection in the negative and positive modes evidenced the well-defined separation of three groups, indicating that there was variance among the soy samples from each warehouse. The samples from warehouses 1 and 3 showed greater similarity in the Hierarchical Cluster Analysis (HCA) in negative mode, while in positive mode, the samples from warehouses 2 and 3 presented greater similarity.
The compositions of the essential oils from the leaves of three domestic varieties of the guava tree Psidium guajava L. (Paluma, Século XXI and Pedro Sato) and of one wild variety were compared. ...Essential oils were extracted by steam distillation, the components were identified by gas chromatography coupled to mass spectrometry GC-MS, and the apparent concentrations were determined by gas chromatography with a flame ionization detector. The results demonstrated that the three essential oils contained many common substances with a prevalence of 1,8-cineole, whereas the essential oil of the Paluma variety contained 1,8-cineole (42.68%) as the major constituent, as well as α-terpineol (38.68%). The principal components of the essential oil of the Século XXI variety were 1,8-cineole (18.83%), trans-caryophyllene (12.08%), and selin-11-en-4-αol (20.98%), while those of the Pedro Sato variety and of the wild plant were 1,8-cineole (17.68%) and (12.83%), caryophyllene oxide (9.34%) and (9.09%), and selin-11-en-4-α-ol (21.46%) and (22.19%), respectively.
Neste estudo, foram analisados os principais componentes químicos
da madeira da Moquinia polymorpha (LESS.) DC., conhecida como candeia
ou cambará, nativa da região Sul de Minas Gerais. A
composição ...química dessa madeira foi: 47,5% de
α-celulose, 25,4% de hemiceluloses A e B, 24,0% de lignina, 73,2%
de holocelulose, 3,82% de extrativos em etanol:cicloexano (1:1, v v-1),
3,21% em etanol e 4,04% em água quente. Nos compostos
voláteis identificados, destacaram-se: α-curcumeno,
α-diidroturmerona, β-diidroturmerona, cedranol,
1-ciclopentil-3-2,4-dimetil-fenilpropano. A análise dos
fenóis totais foi conduzida com base nos extratos
metanol-água (MA) e acetona-água (AA), em que esse
último apresentou maior rendimento. O teor de fenóis totais
foi determinado pelos métodos Folin-Ciocalteau e Azul da
Prússia modificado. No método Folin-Ciocalteau, foram
encontrados 0,93 mg g-1 de madeira para o extrato MA e 1,56 para o
extrato AA e no método azul da Prússia modificado, foram
determinados 2,74 mg g-1 de madeira para o extrato MA e 4,42 para o
extrato AA. O teor de proantocianidinas foi determinado pelos
métodos da vanilina e n-butanol:ácido. No método
n-butanol:ácido, foram encontrados 0,012 mg g-1 de madeira para o
extrato MA e 0,017 para o extrato AA e, no método da vanilina,
foram determinados 0,29 mg g-1 de madeira para o extrato MA e 0,58 para
o extrato AA. Não foram detectados 3-deoxi-proantocianidinas.
Análise da madeira de Pinus oocarpa parte I: estudo dos constituintes macromoleculares e extrativos voláteis Morais, Sérgio Antônio Lemos de(Universidade Federal de Uberlândia Instituto de Química); Nascimento, Evandro Afonso do(Universidade Federal de Uberlândia Instituto de Química); Melo, Dárley Carrijo de(Universidade Federal de Uberlândia Faculdade de Engenharia Química)
Revista árvore,
06/2005, Letnik:
29, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Neste estudo foram analisados os principais componentes químicos da madeira de Pinus oocarpa, cultivado na região do cerrado. A composição química dessa madeira foi: 59,05% de a-celulose, 21,22% de ...hemiceluloses A e B, 25,18% de lignina, 2,78% de extrativos em diclorometano, 4,38% de extrativos em etanol:tolueno, 4,31% de extrativos em água quente e 1,26% de cinzas. O conteúdo de celulose foi relativamente elevado, indicando que essa madeira possui grande potencial para produção de pasta de celulose. Investigou-se, também, a composição dos extrativos. Os principais constituintes do extrato diclorometano dessa madeira foram os ácidos diterpênicos, além dos ácidos palmítico e oléico. No óleo essencial, extraído por aparelho de Clevenger, os principais componentes identificados foram aromadendreno, ledano, hexadecanal e ácido oléico.
The chemical composition of Pinus oocarpa wood cultivated in the Brazilian cerrado was established. The obtained results were: a-cellulose (59.05%), hemicelluloses A and B (21.22%), lignin (25.18%), dichloromethane extractives (2.78%), ethanol:toluene extractives (4.38%), hot water extractives (4.31%) and ash (1.26%). The cellulose content was high. This result opens perspectives for using Pinus oocarpa wood in pulp and paper industries. Most of the dichloromethane extractives were diterpenic, palmitic and oleic acids. The volatile composition, obtained by means of the Clevenger method followed by GC-MS analysis was constituted mainly by aromadendrene, ledane, hexadecanal and oleic acid.
PDF
