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1.
BackgroundBiotechnological processes are part of modern industry as well as stricter environmental requirements. The need to reduce production costs and pollution demands for alternatives that involve the integral use of agro-industrial waste to produce bioactive compounds. The citrus industry generates large amounts of wastes due to the destruction of the fruits by microorganisms and insects together with the large amounts of orange waste generated during the production of juice and for sale fresh. The aim of this study was used orange wastes rich in polyphenolic compounds can be used as source carbon of Aspergillus fumigatus MUM 1603 to generate high added value compounds, for example, ellagic acid and other molecules of polyphenolic origin through submerged fermentation system.ResultsThe orange peel waste had a high concentration of polyphenols, 28% being condensed, 27% ellagitannins, 25% flavonoids and 20% gallotannins. The major polyphenolic compounds were catechin, EA and quercetin. The conditions, using an experimental design of central compounds, that allow the production of the maximum concentration of EA (18.68 mg/g) were found to be: temperature 30°C, inoculum 2 × 107 (spores/g) and orange peel polyphenols 6.2 (g/L).ConclusionThe submerged fermentation process is an effective methodology for the biotransformation of molecules present in orange waste to obtain high value-added as ellagic acid that can be used as powerful antioxidants, antibacterial and other applications.How to cite: Sepúlveda L, Laredo-Alcalá E, Buenrostro-Figueroa JJ, et al. Ellagic acid production using polyphenols from orange peel waste by submerged fermentation. Electron J Biotechnol 2020;43. https://doi.org/10.1016/j.ejbt.2019.11.002.  相似文献   

2.
BackgroundPlastic waste is a serious problem because it is difficult to degrade, thereby leading to global environment problems. Poly(lactic acid) (PLA) is a biodegradable aliphatic polyester derived from renewable resources, and it can be degraded by various enzymes produced by microorganisms. This study focused on the scale-up and evaluated the bioprocess of PLA degradation by a crude microbial enzyme produced by Actinomadura keratinilytica strain T16-1 in a 5 L stirred tank bioreactor.ResultsPLA degradation after 72 h in a 5 L bioreactor by using the enzyme of the strain T16-1 under controlled pH conditions resulted in lactic acid titers (mg/L) of 16,651 mg/L and a conversion efficiency of 89% at a controlled pH of 8.0. However, the PLA degradation process inadvertently produced lactic acid as a potential inhibitor, as shown in our experiments at various concentrations of lactic acid. Therefore, the dialysis method was performed to reduce the concentration of lactic acid. The experiment with a dialysis bag achieved PLA degradation by weight loss of 99.93%, whereas the one without dialysis achieved a degradation of less than approximately 14.75%. Therefore, the dialysis method was applied to degrade a commercial PLA material (tray) with a conversion efficiency of 32%, which was 6-fold more than that without dialysis.ConclusionsThis is the first report demonstrating the scale-up of PLA degradation in a 5 L bioreactor and evaluating a potential method for enhancing PLA degradation efficiency.How to cite: Panyachanakul T, Sorachart B, Lumyong S, et al. Development of biodegradation process for Poly(DL-lactic acid) degradation by crude enzyme produced by Actinomadura keratinilytica strain T16-1. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.04.005  相似文献   

3.
BackgroundSugars from sweet sorghum stalks can be used to produce ethanol and also to grow oleaginous yeasts. Instead of two separate processes, in this paper we propose a different route producing ethanol and microbial oil in two consecutive fermentation steps.ResultsThree yeasts were compared in the first ethanol producing step. In the second step four different oleaginous yeasts were tested. Sweet sorghum juice was first clarified and concentrated. High gravity ethanol fermentation was carried out with concentrated juice with 23.7 g/100 mL of total sugars and without added nutrients. Total sugars were 2.5 times more than the original clarified juice. One yeast gave the best overall response over the two other tested; relative high ethanol productivity, 1.44 g ethanol/L·h−1, and 90% of sugar consumption. Aeration by flask agitation produced superior results than static flasks for all yeasts. Microbial oil production was done employing the residual liquid left after ethanol separation. The pooled residual liquid from the ethanol distillation contained 7.08 g/mL of total carbohydrates, rich in reducing sugars. Trichosporon oleaginosus and Lipomyces starkeyi produced higher dry biomass, total sugar consumption and oil productivity than the other two oleaginous yeasts tested; with values around 25 g/L, 80%, and 0.55 g oil/L·h−1 respectively. However, the biomass oil content in all yeasts was relatively low in the range of 14 to 16%.ConclusionThe two step process is viable and could be considered an integral part of a consolidated biorefinery from sweet sorghum.How to cite: Rolz C, de León R, Mendizábal de Montenegro AL. Co-production of ethanol and biodiesel from sweet sorghum juice in two consecutive fermentation steps. Electron J Biotechnol 2019;41. https://doi.org/10.1016/j.ejbt.2019.05.002.  相似文献   

4.
BackgroundFructose and single cell protein are important products for the food market. Abundant amounts of low-grade dates worldwide are annually wasted. In this study, highly concentrated fructose syrups and single cell protein were obtained through selective fermentation of date extracts by Saccharomyces cerevisiae.ResultsThe effect of air flow (0.1, 0.5, 0.75, 1, 1.25 and 1.5 vvm) and pH (4.5, 4.8, 5, 5.3 and 5.6) was investigated. Higher air flow led to lower fructose yield. The optimum cell mass production of 10 g/L was achieved at air flow of 1.25 vvm with the fructose yield of 91%. Similar cell mass production was obtained in the range pH of 5.0–5.6, while less cell mass was obtained at pH less than 5. Controlling the pH at 4.5, 5.0 and 5.3 failed to improve the production of cell mass which were 5.6, 5.9 and 5.4 g/L respectively; however, better fructose yield was obtained.ConclusionsExtension of the modified Gompertz enabled excellent predictions of the cell mass, fructose production and fructose fraction. The proposed model was also successfully validated against data from literatures. Thus, the model will be useful for wide application of biological processes.How to cite: Putra MD, Abasaeed AE, Al-Zahrani SM. Prospective production of fructose and single cell protein from date palm waste. Electron J Biotechnol 2020;48. https://doi.org/10.1016/j.ejbt.2020.09.007.  相似文献   

5.
BackgroundPyruvic acid (PA), a vital α-oxocarboxylic acid, plays an important role in energy and carbon metabolism. The oleaginous yeast Yarrowia lipolytica (Y. lipolytica) has considerable potential for the production of PA. An increased NaCl concentration reportedly increases the biomass and PA yield of Y. lipolytica.ResultsTo increase the yield of PA, the NaCl-tolerant Y. lipolytica A4 mutant was produced using the atmospheric and room temperature plasma method of mutation. The A4 mutant showed growth on medium containing 160 g/L NaCl. The PA yield of the A4 mutant reached 97.2 g/L at 120 h (0.795 g/g glycerol) in a 20-L fermenter with glycerol as the sole carbon source, which was 28.9% higher than that of the parental strain.ConclusionThe PA yield from Y. lipolytica can be improved by increasing its NaCl tolerance.How to cite: Yuan W, Lin X, Zhong S, et al. Enhanced pyruvic acid yield in an osmotic stress-resistant mutant of Yarrowia lipolytica. Electron J Biotechnol 2020;44. https://doi.org/10.1016/j.ejbt.2020.01.002.  相似文献   

6.
BackgroundThe use of agro-industrial wastes to produce high value-added biomolecules such as biosurfactants is a promising approach for lowering the total costs of production. This study aimed to produce biosurfactants using Rhizopus arrhizus UCP 1607, with crude glycerol (CG) and corn steep liquor (CSL) as substrates. In addition, the biomolecule was characterized, and its efficiency in removing petroderivatives from marine soil was investigated.ResultsA 22 factorial design was applied, and the best condition for producing the biosurfactant was determined in assay 4 (3% CG and 5% CSL). The biosurfactant reduced the surface tension of water from 72 to 28.8 mN/m and produced a yield of 1.74 g/L. The preliminary biochemical characterization showed that the biosurfactant consisted of proteins (38.0%), carbohydrates (35.4%), and lipids (5.5%). The compounds presented an anionic character, nontoxicity, and great stability for all conditions tested. The biomolecule displayed great ability in dispersing hydrophobic substrates in water, thereby resulting in 53.4 cm2 ODA. The best efficiency of the biosurfactant in removing the pollutant diesel oil from marine soil was 79.4%.ConclusionsThis study demonstrated the ability of R. arrhizus UCP1607 to produce a low-cost biosurfactant characterized as a glycoprotein and its potential use in the bioremediation of the hydrophobic diesel oil pollutant in marine soil.How to cite: Pele MA, Ribeaux DR, Vieira ER, et al. Conversion of renewable substrates for biosurfactant production by Rhizopus arrhizus UCP 1607 and enhancing the removal of diesel oil from marine soil. Electron J Biotechnol 2019;38. https://doi.org/10.1016/j.ejbt.2018.12.003.  相似文献   

7.
BackgroundProdigiosin has been demonstrated to be an important candidate in investigating anticancer drugs and in many other applications in recent years. However, industrial production of prodigiosin has not been achieved. In this study, we found a prodigiosin-producing strain, Serratia marcescens FZSF02, and its fermentation strategies were studied to achieve the maximum yield of prodigiosin.ResultsWhen the culture medium consisted of 16.97 g/L of peanut powder, 16.02 g/L of beef extract, and 11.29 mL/L of olive oil, prodigiosin reached a yield of 13.622 ± 236 mg/L after culturing at 26 °C for 72 h. Furthermore, when 10 mL/L olive oil was added to the fermentation broth at the 24th hour of fermentation, the maximum prodigiosin production of 15,420.9 mg/L was obtained, which was 9.3-fold higher than the initial level before medium optimization. More than 60% of the prodigiosin produced with this optimized fermentation strategy was in the form of pigment pellets. To the best of our knowledge, this is the first report on this phenomenon of pigment pellet formation, which made it much easier to extract prodigiosin at low cost. Prodigiosin was then purified and identified by absorption spectroscopy, HPLC, and LCMS. Purified prodigiosin obtained in this study showed anticancer activity in separate experiments on several human cell cultures: A549, K562, HL60, HepG2, and HCT116.ConclusionsThis is a promising strain for producing prodigiosin. The prodigiosin has potential in anticancer medicine studies.How to cite: Lin C, Jia X, Fang Y, et al. Enhanced production of prodigiosin by Serratia marcescens FZSF02 in the form of pigment pellets. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.04.007  相似文献   

8.
BackgroundLiquid wax esters are widely used in cosmetic as well as pharmaceutical and other industries. The demand of organic and natural products is increasing nowadays. Coconut oil contains benefit fatty acids and has been mainly used for oil-based and moisturizer products. Liquid wax esters from coconut oil and unsaturated fatty alcohol can be synthesized by enzymatic reaction; and it is interesting for using as an alternative natural ingredient in these industries.ResultsOptimal condition for coconut oil based wax ester synthesis by immobilized lipase EQ3 was 10 U of enzyme, temperature at 30°C and molar ratio of coconut oil to oleyl alcohol at 1:3 (mol/mol) (0.33X) dissolved in isooctane for 12 h, while for Lipozyme RM IM optimal condition was 10 U of enzyme, temperature at 45°C and oil/alcohol molar ratio at 1:3 (0.33X) dissolved in isooctane for 3 h. Percentage of wax esters synthesized by both lipases reached more than 88%. Both immobilized lipases catalyzed high yield of wax esters within the 2nd batch; after that, the immobilized lipases showed reduced activity and synthesized < 60% of wax esters from the 3rd to 5th batch. The main composition of wax esters was ~ 48% oleyl laurate with 10% degradation at ~ 250°C.ConclusionsThe liquid wax ester synthesis by commercial Lipozyme RM IM had higher effect than immobilized lipase EQ3, but both catalysts were stable within 2 batches in the optimum condition. The characteristic properties of wax esters showed potential for use as components in cosmetics and skin care products.How to citeUngcharoenwiwat P, H-Kittikun A. Enzymatic synthesis of coconut oil based wax esters by immobilized lipase EQ3 and commercial lipozyme RMIM. Electron J Biotechnol 2020;47. https://doi.org/10.1016/j.ejbt.2020.06.005  相似文献   

9.
BackgroundThe amount of municipal solid waste (MSW) gradually increased along with the rapid development of modern cities. A large amount of landfill leachate are generated with excessive chemical oxygen demand (COD), which create a great deal of pressure on the environment-friendly treatment process. Anaerobic digestion is an ideal technique to solve the above problem.ResultsA thermophilic granular sludge was successfully adapted for anaerobic digestion of MSW leachate (from an aging large-scale landfill) for methane production. The COD degradation efficiency improved by 81.8%, while the methane production rate reached 117.3 mL CH4/(g VS d), which was 2.34-fold more than the control condition. The bacterial and archaeal communities involved in the process were revealed by 16S rRNA gene high-throughput pyrosequencing. The richness of the bacterial community decreased in the process of thermophilic granular sludge, while the archaeal community structure presented a reverse phenomenon. The bacterial genus, Methanosaeta was the most abundant during the mesophilic process, while Methanobacterium, Methanoculleus, Methanosaeta and Methanosarcina were more evenly distributed. The more balanced community distribution between hydrogenotrophic and acetotrophic methanogens implied a closer interaction between the microbes, which further contributed to higher methane productivity. The detailed relationship between the key functional communities and anaerobic digestion performances were demonstrated via the multivariate canonical correspondence analysis.ConclusionsWith the assistance of adaptive thermophilic granular sludge, microbial community structure was more evenly distributed, while both of COD degradation rate and methane production was improved during anaerobic digestion of MSW landfill leachate.How to cite: Feng S, Hou S, Huang X, et al. Insights into the microbial community structure of anaerobic digestion of municipal solid waste landfill leachate for methane production by adaptive thermophilic granular sludge. Electron J Biotechnol 2019;39. https://doi.org/10.1016/j.ejbt.2019.04.001.  相似文献   

10.
BackgroundMilk whey, a byproduct of the dairy industry has a negative environmental impact, can be used as a raw material for added-value compounds such as galactooligosaccharides (GOS) synthesis by β-galactosidases.ResultsB-gal42 from Pantoea anthophila strain isolated from tejuino belonging to the glycosyl hydrolase family GH42, was overexpressed in Escherichia coli and used for GOS synthesis from lactose or milk whey. Crude cell-free enzyme extracts exhibited high stability; they were employed for GOS synthesis reactions. In reactions with 400 g/L lactose, the maximum GOS yield was 40% (w/w) measured by HPAEC-PAD, corresponding to 86% of conversion. This enzyme had a strong predilection to form GOS with β(1 → 6) and β(1 → 3) galactosyl linkages. Comparing GOS synthesis between milk whey and pure lactose, both of them at 300 g/L, these two substrates gave rise to a yield of 38% (60% of lactose conversion) with the same product profile determined by HPAEC-PAD.ConclusionsB-gal42 can be used on whey (a cheap lactose source) to produce added value products such as galactooligosaccharides.How to cite: Yañez-Ñeco CV, Cervantes FV, Amaya-Delgado L, et al. Synthesis of β(1→3) and β(1→6) galactooligosaccharides from lactose and whey using a recombinant β-galactosidase from Pantoea anthophila. Electron J Biotechnol 2021;49. https://dx.doi.org/10.1016/j.ejbt.2020.10.004  相似文献   

11.
BackgroundRosemary (Rosmarinus officinalis) contains active substances that have desirable properties for industrial and herbal medicine applications, e.g., essential oils (1.5–2.5%), tannins, flavonoids, triterpenes, saponins, resins, phytosterols, rosmarinic acid and many others. The aim of this study was to determine the influence of rosemary extract and 20% rapeseed oil substitution for animal fat on storage changes and inhibition of cholinesterases in liver pâté.ResultsPreliminary research showed that rosemary extract exhibited antioxidative activity in the system of accelerated Rancimat and Oxidograph tests. Then, rosemary extract was used as an ingredient in liver pâté. During the experiment, meat samples were refrigerated and tested on days 1, 5, 8, 12 and 15 after production. The study proved that the substitution of 20% of animal fat with rapeseed oil decreased the content of saturated acids and increased the content of monoenic fatty acids by approximately 5% and polyene fatty acids by 40%.ConclusionsIn addition to antioxidative activity, the rosemary extract affected the health-promoting value of the samples, which inhibited cholinesterase activity during the entire storage period. The extract inhibited AChE more than BChE.How to cite: Bilska A, Kobus-Cisowska J, Kmiecik D, et al. Cholinesterase inhibitory activity, antioxidative potential and microbial stability of innovative liver pâté fortified with rosemary extract (Rosmarinus officinalis). Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.03.007  相似文献   

12.
BackgroundFuels and chemicals from renewable feedstocks have a growing demand, and acetone, butanol and ethanol (ABE) are some relevant examples. These molecules can be produced by the bacterial fermentation process using hydrolysates generated from lignocellulosic biomass as sugarcane bagasse, one of the most abundant sources of lignocellulosic biomass in Brazil. It originates as a residue in mills and distilleries in the production of sugar and ethanol.ResultsIn the present work, two strategies to generate hydrolysates of sugarcane bagasse were adopted. The fermentation of the first hydrolysate by Clostridium acetobutylicum DSM 6228 resulted in final concentrations of butanol, acetone and ethanol of 6.4, 4.5 and 0.6 g/L, respectively. On the other hand, the second hydrolysate presented better results (averages of 9.1, 5.5 and 0.8 g/L, respectively), even without the need for nutrient supplementation, since key elements were already present in the medium. The productivity (QP) and yield (YP/S) of the solvents with second hydrolysate were 0.5 g/L·h-1 and 0.4 g/g, respectively.ConclusionsThe results described herein open new perspectives for the production of important molecules from residual lignocellulosic biomass for the fuel and chemical industries within the context of second-generation biorefinery.How to cite: Gomes AC, Rodrigues MI, Passos DF, et al. Acetone-butanol-ethanol fermentation from sugarcane bagasse hydrolysates: utilization of C5 and C6 sugars. Electron J Biotechnol 2019;42. https://doi.org/10.1016/j.ejbt.2019.10.004.  相似文献   

13.
BackgroundAmmonium stress is a prime limiting phenomenon that occurs during methane formation from poultry manure. It is caused by elevated ammonium nitrogen concentrations that result from substrate decomposition. The amounts of methane formed depend on the activity of methanogenic microbes.ResultsDuring the research reported in this paper, the response of a mesophilic consortium inhabiting a biogas reactor to rising load of poultry manure was investigated. The taxonomic composition of bacterial population was mostly typical, however syntrophic bacteria were not detected. This absence resulted in limitation of succession of some methanogenic microorganisms, especially obligate hydrogenotrophs. The methanogenic activity of the consortium was totally dependent on the activity of Methanosaeta. Inhibition of methanoganesis was noticed at ammonium nitrogen concentration of 3.68 g/L, total cessation occurred at 5.45 g/L. Significant amounts of acetic acid in the fermentation pulp accompanied the inhibition.ConclusionsThe effectiveness of the consortium was totally dependent on the metabolic activity of the acetoclastic Methanoseata genus and lack of SAOB did not allow hydrogenotrophic methanogens to propagate and lead to cessation of biogas production at an elevated ammonium concentration at which acetoclastic methanogens were inhibited.How to cite: Świątek M, Lewicki A, Szymanowska D, et al. The effect of introduction of chicken manure on the biodiversity and performance of an anaerobic digester. Electron J Biotechnol 2019;37. https://doi.org/10.1016/j.ejbt.2018.11.002.  相似文献   

14.
BackgroundLawsonia intracellularis remains a problem for the swine industry worldwide. Previously, we designed and obtained a vaccine candidate against this pathogen based on the chimeric proteins: OMP1c, OMP2c, and INVASc. These proteins formed inclusion bodies when expressed in E. coli, which induced humoral and cellular immune responses in vaccinated pigs. Also, protection was demonstrated after the challenge. In this study, we established a production process to increase the yields of the three antigens as a vaccine candidate.ResultsBatch and fed-batch fermentations were evaluated in different culture conditions using a 2 L bioreactor. A fed-batch culture with a modified Terrific broth medium containing glucose instead of glycerol, and induced with 0.75 mM IPTG at 8 h of culture (11 g/L of biomass) raised the volumetric yield to 627.1 mg/L. Under these culture conditions, plasmid-bearing cells increased by 10% at the induction time. High efficiency in cell disruption was obtained at passage six using a high-pressure homogenizer and a bead mill. The total antigen recovery was 64% (400 mg/L), with a purity degree of 70%. The antigens retained their immunogenicity in pigs, inducing high antibody titers.ConclusionsConsidering that the antigen production process allowed an increment of more than 70-fold, this methodology constitutes a crucial step in the production of this vaccine candidate against L. intracellularis.How to cite: Salazar S, Gutiérrez N, Sánchez O, et al. Establishment of a production process for a novel vaccine candidate against Lawsonia intracellularis. Electron J Biotechnol 2021.https://doi.org/10.1016/j.ejbt.2021.01.002  相似文献   

15.
BackgroundOleaginous yeasts can be grown on different carbon sources, including lignocellulosic hydrolysate containing a mixture of glucose and xylose. However, not all yeast strains can utilize both the sugars for lipogenesis. Therefore, in this study, efforts were made to isolate dual sugar-utilizing oleaginous yeasts from different sources.ResultsA total of eleven isolates were obtained, which were screened for their ability to utilize various carbohydrates for lipogenesis. One promising yeast isolate Trichosporon mycotoxinivorans S2 was selected based on its capability to use a mixture of glucose and xylose and produce 44.86 ± 4.03% lipids, as well as its tolerance to fermentation inhibitors. In order to identify an inexpensive source of sugars, nondetoxified paddy straw hydrolysate (saccharified with cellulase), supplemented with 0.05% yeast extract, 0.18% peptone, and 0.04% MgSO4 was used for growth of the yeast, resulting in a yield of 5.17 g L−1 lipids with conversion productivity of 0.06 g L−1 h−1. Optimization of the levels of yeast extract, peptone, and MgSO4 for maximizing lipid production using Box–Behnken design led to an increase in lipid yield by 41.59%. FAME analysis of single cell oil revealed oleic acid (30.84%), palmitic acid (18.28%), and stearic acid (17.64%) as the major fatty acids.ConclusionThe fatty acid profile illustrates the potential of T. mycotoxinivorans S2 to produce single cell oil as a feedstock for biodiesel. Therefore, the present study also indicated the potential of selected yeast to develop a zero-waste process for the complete valorization of paddy straw hydrolysate without detoxification.How to cite: Sagia S, Sharma A, Singh S, et al. Single cell oil production by a novel yeast Trichosporon mycotoxinivorans for complete and ecofriendly valorization of paddy straw. Electronic Journal of Biotechnology 2020;44. https://doi.org/10.1016/j.ejbt.2020.01.009.  相似文献   

16.
BackgroundCecropin P1, acting as an antimicrobial, has a broad-spectrum antibacterial activity with some antiviral and antifungal properties. It is a promising natural alternative to antibiotics which is originally isolated from the pig intestinal parasitic nematode Ascaris suum. Many studies have shown that Cecropin P1 is helpful for the prevention or treatment of clinical diseases. Therefore, it is very necessary to establish a safe, nontoxic, and efficient expression method of Cecropin P1.ResultsThe results indicated that the recombinant protein was about 5.5 kDa showed by Tricine–SDS–PAGE and Western blot. And Cecropin P1 was efficiently secreted and expressed after 12 h of induction, with an increasing yield over the course of the induction. Its maximum concentration was 7.83 mg/L after concentration and purification. In addition, in vitro experiments demonstrated that Cecropin P1 not only exerted a strong inhibitory effect on Escherichia coli, Salmonella sp., Shigella sp., and Pasteurella sp., but also displayed an antiviral activity against PRRSV NADC30-Like strain.ConclusionsCollectively, the strategy of expressing Cecropin P1 in Saccharomyces cerevisiae is harmless, efficient, and safe for cells. In addition, the expressed Cecropin P1 has antiviral and antibacterial properties concurrently.How to cite: Jiang R, Zhang P, Wu X, et al., Expression of antimicrobial peptide Cecropin P1 in Saccharomyces cerevisiae and its antibacterial and antiviral activity in vitro. Electron J Biotechnol 2021;50. https://doi.org/10.1016/j.ejbt.2020.12.006  相似文献   

17.
BackgroundFoods including probiotics are considered “functional foods.” As an alternative to dairy products, we investigated the behavior of Lactobacillus casei when exposed to low-pH fruit juice. Juices of fruits such as pineapple, raspberry, and orange were assessed. Free and microencapsulated forms of L. casei were compared, and the viability of the probiotic was evaluated under storage at 4°C for 28 d. Microbiological analyses were carried out to ensure a safe and healthy product for consumers who look for foods with probiotics from sources other than dairy.ResultsLow pH affected L. casei survival during storage depending on the type of fruit juice. In the case of pineapple juice, some microcapsules were broken, but microcapsules recovered at the end of the storage period had 100% viability (2.3 × 107 CFU/g spheres). In the case of orange juice, more than 91% viability (5.5 × 106 CFU/g spheres) was found. In raspberry juice, viability decreased rapidly, disappearing at the end of the storage period, which was caused by the absorption of high concentrations of anthocyanin inside microcapsules more than low pH.ConclusionLow pH affected the survival of L. casei under refrigeration; even when they were microencapsulated, acidic conditions impacted their viability. Although pH affects viability, its value is very sensitive and will depend on the type of fruit juice and its composition. Some fruit juices contain compounds used as substrates for Lactobacillus and other compounds with antimicrobial effects.How to cite: Olivares A, Soto C, Caballero E, et al. Survival of microencapsulated Lactobacillus casei (prepared by vibration technology) in fruit juice during cold storage. Electron J Biotechnol 2019;42. https://doi.org/10.1016/j.ejbt.2019.10.002.  相似文献   

18.
19.
BackgroundVibrio species display variable and plastic fitness strategies to survive and interact with multiple hosts, including marine aquaculture species that are severely affected by pathogenic Vibrios. The culturable Vibrio sp. strain ArtGut-C1, the focus of this study, provides new evidence of such phenotypic plasticity as it accumulates polyhydroxybutyrate (PHB), a biodegradable polymer with anti-pathogen activity, particularly in the marine larviculture phase. The strain was isolated from the gut of laboratory-reared Artemia individuals, the live diet and PHB carrier used in larviculture. Its main phenotypic properties, taxonomic status and genomic properties are reported based on the whole-genome sequencing.ResultsVibrio sp. ArtGut-C1 yielded 72.6% PHB of cells’ dry weight at 25°C. The genomic average nucleotide identity (ANI) shows it is closely related to V. diabolicus (ANI: 88.6%). Its genome contains 5,236,997-bp with 44.8% GC content, 3,710 protein-coding sequences, 96 RNA, 9 PHB genes functionally related to PHB metabolic pathways, and several genes linked to competing and colonizing abilities.ConclusionsThis culturable PHB-accumulating Vibrio strain shows high genomic and phenotypic variability. It may be used as a natural pathogen biocontrol in the marine hatchery and as a potential cell factory for PHB production.How to cite: Yévenes M, Quiroz M, Maruyama F, et al. Vibrio sp. ArtGut-C1, a polyhydroxybutyrate producer isolated from the gut of the aquaculture live diet Artemia (Crustacea). Electron J Biotechnol 2021;49. https://doi.org/10.1016/j.ejbt.2020.10.003  相似文献   

20.
BackgroundEthanol concentration (PE), ethanol productivity (QP) and sugar consumption (SC) are important values in industrial ethanol production. In this study, initial sugar and nitrogen (urea) concentrations in sweet sorghum stem juice (SSJ) were optimized for high PE (≥ 10%, v/v), QP, (≥ 2.5 g/L·h) and SC (≥ 90%) by Saccharomyces cerevisiae SSJKKU01. Then, repeated-batch fermentations under normal gravity (NG) and high gravity (HG) conditions were studied.ResultsThe initial sugar at 208 g/L and urea at 2.75 g/L were the optimum values to meet the criteria. At the initial yeast cell concentration of ~ 1 × 108 cells/mL, the PE, QP and SC were 97.06 g/L, 3.24 g/L·h and 95.43%, respectively. Repeated-batch fermentations showed that the ethanol production efficiency of eight successive cycles with and without aeration were not significantly different when the initial sugar of cycles 2 to 8 was under NG conditions (~ 140 g/L). Positive effects of aeration were observed when the initial sugar from cycle 2 was under HG conditions (180–200 g/L). The PE and QP under no aeration were consecutively lower from cycle 1 to cycle 6. Additionally, aeration affected ergosterol formation in yeast cell membrane at high ethanol concentrations, whereas trehalose content under all conditions was not different.ConclusionInitial sugar, sufficient nitrogen and appropriated aeration are necessary for promoting yeast growth and ethanol fermentation. The SSJ was successfully used as an ethanol production medium for a high level of ethanol production. Aeration was not essential for repeated-batch fermentation under NG conditions, but it was beneficial under HG conditions.How to cite: Sriputorn B, Laopaiboon P, Phukoetphim N, et al. Enhancement of ethanol production efficiency in repeated-batch fermentation from sweet sorghum stem juice: Effect of initial sugar, nitrogen and aeration. Electron J Biotechnol 2020;46. https://doi.org/10.1016/j.ejbt.2020.06.001  相似文献   

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