Environmentally Friendly Production of D(−) Lactic Acid by Sporolactobacillus nakayamae

The interest in the production of lactic acid has increased due to its wide range of applications. In the present study, the variables that affect fermentative D(−) lactic acid production were investigated: neutralizing agents, pH, temperature, inoculum percentage, agitation, and concentration of the medium components. An experimental design was applied to determine the optimal concentrations of the medium components and fermentation was studied using different feeding strategies. High production (122.41 g/L) and productivity (3.65 g/L·h) were efficiently achieved by Sporolactobacillus nakayamae in 54 h using a multipulse fed-batch technique with an initial medium containing 35 g/L of yeast extract (byproduct of alcohol production), 60 g/L of crystallized sugar, and 7.5 mL/L of salts. The fermentation process was conducted at 35°C and pH 6.0 controlled by NaOH with a 20% volume of inoculum and agitation at 125 rpm. The production of a high optically pure concentration of D(−) lactic acid combined with an environmentally friendly NaOH-based process demonstrates that S. nakayamae is a promising strain for D(−) lactic acid production

Biochars from Spirulina as an alternative material in the purification of lactic acid from a fermentation broth

In this study, Spirulina biochar obtained from fast pyrolysis was evaluated as an alternative to commercial activated carbon for lactic acid (LA) purification from a fermentation broth. Thermally (350 and 400 C treatment of the biochar in N2 atmosphere for 4 h) and chemically (KOH solution impregnation of the algal material and fast pyrolysis to obtain the biochar) activated Spirulina biochars were also tested. The biochars were previously characterized using SEM and FT-IR. Two purification methodologies were evaluated: filtration and stirring. The stirring method prove to be simpler, faster and chipper, with excellent purification results. All the evaluated biochars presented a performance comparable to that of activated carbon in the stirring methodology. Spirulina biochar and the KOH activated biochar were the once with the best results, with 92 and 82% LA recovery and 82 and 90% protein removal efficiencies, respectively.Fil: Piloni, Roxana Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Coelho, Luciana Fontes. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Sass, Daiane Cristina. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Lanteri, Mario Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Transferencia de Villa María. Universidad Nacional de Villa María. Centro de Investigaciones y Transferencia de Villa María; ArgentinaFil: Bertochi, Maria Aparecida Zaghete. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Moyano, Elizabeth Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Contiero, Jonas. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi

Oregano essential oil and its main components Thymol and Carvacrol as alternatives to control citrus canker

Plant Essential Oils and their constituents are well-known for their properties as antimicrobial agents and are labeled as Generally Recognized as Safe (GRAS), prompting studies around their usage in the control of food-borne microorganisms and phytopathogens. In this study, we evaluated Oregano Essential Oil (OEO), Thymol (THY) and Carvacrol (CAR) for the control of Xanthomonas citri subsp. citri (X. citri). In vitro antibacterial assays revealed that CAR and THY inhibit X. citri growth at the concentrations of 100 µg.mL-1 and 114 µg.mL-1, lower than OEO (136 µg.mL-1). Bactericidal effects were observed at 400 µg.mL-1 for OEO and 200 ug.mL-1 for CAR and THY. Investigating potential cellular targets for the compounds showed that after 30 minutes of exposure up to 84% of the cells had their membranes disrupted, implicating the membrane as the primary target. Phytotoxicity evaluations using Lactuca sativa and Solanum lycopersicum seeds showed an acute toxic effect in all treatments above 200 µg.mL-1, except for OEO and THY in S. lycopersicum at lower concentrations. Regarding their protective effect on citrus leaves, CAR showed no effect when compared to the untreated control (0.39 and 0.50 lesions per cm2, respectively). OEO and THY were able to reduce significantly citrus canker symptoms (0.18 and 0.11 lesions per cm2, respectively). In addition, no toxic effects were observed on citrus leaves in all treatments. THY inhibits X. citri growth and the development of citrus canker lesions. These results show that THY as a viable alternative to be used in citrus canker management

Complete ¹H and 13C NMR structural assignments for a group of four goyazensolide-type furanoheliangolides

Four goyazensolide-type sesquiterpene lactones - lychnofolide, centratherin, goyazensolide and goyazensolide acetate - were thoroughly studied by NMR experimental techniques. ¹H NMR, 13C NMR {¹H}, COSY, HMQC, HMBC, J-res. and NOE experiments were performed to provide the needed structural information. Complete and unequivocal assignment, including the determination of all multiplicities, was obtained for each structure and the data collections are presented in tables

Biomimetic Synthesis of Eremantholide

Neste trabalho foram desenvolvidos alguns estudos que tiveram como objetivo principal a transformação de furanoeliangolidos contendo a unidade -metileno--butirolactona em eremantolidos, através da reação de adição 1,4 de hidreto seguida de ciclização, realizada pelo reagente de Stryker [(Ph3PCuH)6].In this work we describe our studies for the biomimetic transformation of furanoheliangolides into eremantholides using the Strykers reagent [(Ph3PCuH)6]

Xylan Solubilization from Partially Delignified Biomass, and Residual Lignin Removal from Solubilized Xylan

Xylan is a macromolecule of industrial interest that can be solubilized from lignocellulosic materials, such as sugarcane bagasse, which is a renewable source. However, the solubilization methods of xylan need to be better developed for use in industrial applications. The main objective of this study was to evaluate xylan solubilization methods with higher yields and purity by using biomasses/fractions of sugarcane: leaf and stem, internode, node, and external fraction. Two strategies were evaluated by applying diluted sodium chlorite, sodium sulfite, and hydrogen peroxide: a delignification of the biomass before xylan solubilization; and the delignification of the solubilized xylan for residual lignin removal. The delignification of the biomass before the xylan solubilization enabled to identify material and specific conditions for yields higher than 90%. Residual lignin varied from 3.14 to 18.06%, with hydrogen peroxide in alkaline medium partial delignification shown to be effective. The delignification of xylan presented better results using diluted hydrogen peroxide, with a reduction of 58.44% of the initial lignin content. The solubilized xylans were used as a substrate for xylanase activities, resulting in higher activity than commercial xylan. In the delignification of the biomasses, hydrogen peroxide was the reagent with better results concerning the yield, purity, and solubility of the xylan. This reagent (diluted) was also better in the delignification of the solubilized xylan, resulting in lower residual lignin content. The solubility and purity tests (low salt content) indicated that the solubilized xylan presented characteristics that were similar to or even better than commercial xylan

EPS Production by <i>Lacticaseibacillus casei</i> Using Glycerol, Glucose, and Molasses as Carbon Sources

This study demonstrates that Lactobacillus can produce exopolysaccharides (EPSs) using alternative carbon sources, such as sugarcane molasses and glycerol. After screening 22 strains of Lactobacillus to determine which achieved the highest production of EPS based on dry weight at 37 °C, the strain Ke8 (L. casei) was selected for new experiments. The EPS obtained using glycerol and glucose as carbon sources was classified as a heteropolysaccharide composed of glucose and mannose, containing 1730 g.mol−1, consisting of 39.4% carbohydrates and 18% proteins. The EPS obtained using molasses as the carbon source was characterized as a heteropolysaccharide composed of glucose, galactose, and arabinose, containing 1182 g.mol−1, consisting of 52.9% carbohydrates and 11.69% proteins. This molecule was characterized using Size Exclusion Chromatography (HPLC), Gas chromatography–mass spectrometry (GC-MS), Fourier-transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance spectroscopy (1H-NMR). The existence of polysaccharides was confirmed via FT-IR and NMR analyses. The results obtained suggest that Lacticaseibacillus casei can grow in media that use alternative carbon sources such as glycerol and molasses. These agro-industry residues are inexpensive, and their use contributes to sustainability. The lack of studies regarding the use of Lacticaseibacillus casei for the production of EPS using renewable carbon sources from agroindustry should be noted

L-(+)-Lactic acid production by Lactobacillus rhamnosus B103 from dairy industry waste

ABSTRACT Lactic acid, which can be obtained through fermentation, is an interesting compound because it can be utilized in different fields, such as in the food, pharmaceutical and chemical industries as a bio-based molecule for bio-refinery. In addition, lactic acid has recently gained more interest due to the possibility of manufacturing poly(lactic acid), a green polymer that can replace petroleum-derived plastics and be applied in medicine for the regeneration of tissues and in sutures, repairs and implants. One of the great advantages of fermentation is the possibility of using agribusiness wastes to obtain optically pure lactic acid. The conventional batch process of fermentation has some disadvantages such as inhibition by the substrate or the final product. To avoid these problems, this study was focused on improving the production of lactic acid through different feeding strategies using whey, a residue of agribusiness. The downstream process is a significant bottleneck because cost-effective methods of producing high-purity lactic acid are lacking. Thus, the investigation of different methods for the purification of lactic acid was one of the aims of this work. The pH-stat strategy showed the maximum production of lactic acid of 143.7 g/L. Following purification of the lactic acid sample, recovery of reducing sugars and protein and color removal were 0.28%, 100% and 100%, respectively

Solvent Effect in Reactions Using Stryker's Reagent

The solvent has a significant influence in the rate of reactions promoted by Stryker's reagent The reactions performed in THF were, in most cases, faster than in toluene.FAPESPFAPESPCNPqCNPqCAPESCAPE