scholarly journals Optimization and qualitative comparison of two vinasse pre-treatments aiming at microalgae cultivation

2021 ◽  
Vol 26 (2) ◽  
pp. 359-367
Author(s):  
Camila Candido ◽  
André Bernardo ◽  
Ana Teresa Lombardi

ABSTRACT The cultivation of microalgae is a possible destination for vinasse, a residue from the sugar and alcohol industry. This use can help reduce the costs of microalgae production and remediate this residue rich in nutrients. However, the physicochemical characteristics of vinasse limit its use for microalgae growth at low concentrations, except when the residue is pretreated. This work aimed at optimizing the vinasse pretreatments of centrifugation and adsorption by smectite clay and activated charcoal on laboratory scale in terms of amounts of materials used and time spent, making them more viable on larger scales. The optimized processes were then compared in productive, economic, and environmental terms. The dilution of treated vinasse with distilled water resulted in similar growth of Chlorella vulgaris to those obtained with the dilution in BG11 medium, indicating that the addition of nutrients in culture media is not necessary. Although microalgae growth occurs in higher concentrations of vinasse treated by adsorption, the results show that centrifugation required less processing time, has cheaper processing costs, and generated much less residue. Centrifugation treatment has greater economic and environmental viabilities and was more sustainable than the adsorption, even though the algae did not grow in the centrifuged residue in concentrations as high as it did after the adsorption treatment. Therefore, this article brings a new view about the economic and environmental aspects on the use of pretreated vinasse for microalgal growth, giving a lucrative destination for a highly polluting waste.

2021 ◽  
Author(s):  
Christine Poon

AbstractArthroplasty implants e.g. hip, knee, spinal disc sustain relatively high compressive loading and friction wear, which lead to the formation of wear particles or debris between articulating surfaces. Despite advances in orthopaedic materials and surface treatments, the production of wear debris from any part of a joint arthroplasty implant is currently unavoidable. Implant wear debris induces host immune responses and inflammation, which causes patient pain and ultimately implant failure through progressive inflammation-mediated osteolysis and implant loosening, where the severity and rate of periprosthetic osteolysis depends on the material and physicochemical characteristics of the wear particles. Evaluating the cytotoxicity of implant wear particles is important for regulatory approved clinical application of arthroplasty implants, as is the study of cell-particle response pathways. However, the wear particles of polymeric materials commonly used for arthroplasty implants tend to float when placed in culture media, which limits their contact with cell cultures. This study reports a simple means of suspending wear particles in liquid medium using sodium carboxymethyl cellulose (NaCMC) to provide a more realistic proxy of the interaction between cells and tissues to wear particles in vivo, which are free-floating in synovial fluid within the joint cavity. Low concentrations of NaCMC dissolved in culture medium were found to be effective for suspending polymeric wear particles. Such suspensions may be used as more physiologically-relevant means for testing cellular responses to implant wear debris, as well as studying the combinative effects of shear and wear particle abrasion on cells in a dynamic culture environments such as perfused tissue-on-chip devices.


Author(s):  
Odilon D. Kaboré ◽  
Sylvain Godreuil ◽  
Michel Drancourt

Traditionally recognized as environmental bacteria, Planctomycetes have just been linked recently to human pathology as opportunistic pathogens, arousing a great interest for clinical microbiologists. However, the lack of appropriate culture media limits our future investigations as no Planctomycetes have ever been isolated from patients’ specimens despite several attempts. Several Planctomycetes have no cultivable members and are only recognized by 16S rRNA gene sequence detection and analysis. The cultured representatives are slow-growing fastidious bacteria and mostly difficult to culture on synthetic media. Accordingly, the provision of environmental and nutritional conditions like those existing in the natural habitat where yet uncultured/refractory bacteria can be detected might be an option for their potential isolation. Hence, we systematically reviewed the various natural habitats of Planctomycetes, to review their nutritional requirements, the physicochemical characteristics of their natural ecological niches, current methods of cultivation of the Planctomycetes and gaps, from a perspective of collecting data in order to optimize conditions and the protocols of cultivation of these fastidious bacteria. Planctomycetes are widespread in freshwater, seawater, and terrestrial environments, essentially associated to particles or organisms like macroalgae, marine sponges, and lichens, depending on the species and metabolizable polysaccharides by their sulfatases. Most Planctomycetes grow in nutrient-poor oligotrophic environments with pH ranging from 3.4 to 11, but a few strains can also grow in quite nutrient rich media like M600/M14. Also, a seasonality variation of abundance is observed, and bloom occurs in summer-early autumn, correlating with the strong growth of algae in the marine environments. Most Planctomycetes are mesophilic, but with a few Planctomycetes being thermophilic (50°C to 60°C). Commonly added nutrients are N-acetyl-glucosamine, yeast-extracts, peptone, and some oligo and macro-elements. A biphasic host-associated extract (macroalgae, sponge extract) conjugated with a diluted basal medium should provide favorable results for the success of isolation in pure culture.


1978 ◽  
Vol 110 (4) ◽  
pp. 443-448 ◽  
Author(s):  
R. P. Jaques ◽  
D. R. Laing

AbstractThe efficacy of mixtures of chlordimeform with Bacillus thuringiensis and(or) Autographa californica nuclear polyhedrosis virus and Pieris rapae granulosis virus against Trichoplusia ni and Pieris rapae on the late cabbage was assessed in field plots over four growing seasons. Mixtures of 0.07 kg of chlordimeform/ha (1/8 of the recommended dosage) with low concentrations of the microbial insecticides were as effective or more effective than the materials used alone at full rates. The advantages of such mixtures in pest management are discussed.


1971 ◽  
Vol 133 (2) ◽  
pp. 231-259 ◽  
Author(s):  
Thomas C. Jones ◽  
James G. Hirsch

Methods have been devised for establishing infection in vitro of mouse macrophages and fibroblasts with Mycoplasma pulmonis. The mycoplasmas attached to the cells and under appropriate cultural conditions grew into a lawn of microorganisms covering most of the cell surface. The mycoplasmas grew abundantly on fibroblasts cultured in minimal essential medium containing 20% fetal calf serum; supplementation of this medium with heart infusion broth was necessary to obtain similar growth on macrophages. The infection of these cells appeared to be essentially an extracellular process; only rarely were partially degraded mycoplasmas seen with phagocytic vacuoles. The addition to heavily infected macrophage cultures of low concentrations of anti-mycoplasma antibody stimulated rapid, massive phagocytosis of the surface microorganisms. In sharp contrast, the same antiserum had no discernable effect on the mycoplasma-fibroblast relationship. The antibody effect in the macrophage system was apparently a direct opsonic one rather than an indirect result of microbial killing, since the mycoplasmas in macrophage or fibroblast cultures incorporated labelled thymidine into DNA after the addition of antiserum to the medium. The phagocytic event and the subsequent fate of the mycoplasmas were studied in detail after the addition of antibody to the macrophage cultures. Phase-contrast cinemicrophotography revealed membrane ruffles surrounding the surface mycoplasmas and disappearance from view of the organisms; 10–30 min later translucent grapelike clusters were seen in large phagocytic vacuoles. On electronmicroscopic study the surface mycoplasmas were surrounded by pincers-like projections of the macrophage. Numerous mycoplasmas were seen in phagocytic vacuoles; in the early minutes after the addition of antibody the intracellular mycoplasmas appeared normal, but within 2 hr they appeared partially degraded with a central electron-lucent area and electron-opaque deposits at the microbial cell margin. 24 hr after the addition of antiserum, digestion of the mycoplasmas was nearly complete; the cells appeared normal except for large residual bodies composed of amorphous moderately dense material and increased lipid deposits. Degradation of mycoplasmas within macrophages was also studied using infected cultures in which the mycoplasmas, but not the macrophages, had incorporated tritiated thymidine into DNA. The appearance of large amounts of acid-soluble radiolabel after phagocytosis stimulated by antibody confirmed the degradation of the intracellular mycoplasmas.


2018 ◽  
Author(s):  
Fan Feng ◽  
Zijin Li ◽  
Zhenlang Chen ◽  
Le Wang ◽  
Jie Huang ◽  
...  

AbstractThrombosis remains one of the leading causes of mortality and morbidity in the world. Thrombin is a key enzyme involved in the blood clotting processes, which can be intervened by low concentrations of Hirudin. The C-terminal dodecapeptide of Hirudin was capable of inhibiting thrombosis. This peptide has been partially randomized in this report, and the coding sequences have been expressed in yeast as chimerical peptides for secretion into the culture media. Two other semi-random modules have been processed likewise. The supernatant was subsequently tested for anti-thrombin activities. DNA sequencing indicated that the putative positive clone encoded a single serine residue followed by a stop codon. The Ninhydrin assay of the culture supernatant of the positive clone indicated a high content of amino acid. Electrospray Mass Spectrometry showed a distinct peak at 430.5 when the expression products from Pichia pastoris were examined, suggesting that the compound may be a dimannosylated serine, as yeast possesses glycosylation at serine residues. The observed effects of α-Mannosidase treatments on the function of yeast induction products are consistent with this assumption. Partial randomization of peptides and proteins may accelerate directed evolution, yielding unprecedented number of variants for functional interrogation and drug development.


2021 ◽  
Vol 4 (3) ◽  
pp. 90-94
Author(s):  
Pablo Augusto Gulhões ◽  
Alexia Ananda Santana Simões ◽  
Jársia de Melo dos Santos ◽  
Edna dos Santos Almeida

This work aimed to evaluate the growth and cost cultivation of Chlorella sp microalgae in PA and commercial urea medium solutions compared to BBM standard medium. We cultivated the microalgae Chlorella sp in BBM, PA urea, and commercial urea media, evaluating their growth for 8 days. In addition, we appraised the cost of the culture media considering the quotation of the reagents and the mass used for pilot-scale cultivation (100l). It was possible to observe the similar growth of microalgae with urea PA and BBM. The use of urea PA as a culture media for microalgae has the potential to reduce the cost of the medium by 68%. Thus, the cultivation of Chlorella in urea medium represents an alternative to reduce the production costs of biomass from this microorganism.


Cells ◽  
2018 ◽  
Vol 7 (12) ◽  
pp. 273 ◽  
Author(s):  
Sara Busatto ◽  
George Vilanilam ◽  
Taylor Ticer ◽  
Wen-Lang Lin ◽  
Dennis Dickson ◽  
...  

Concentration of extracellular vesicles (EVs) from biological fluids in a scalable and reproducible manner represents a major challenge. This study reports the use of tangential flow filtration (TFF) for the highly efficient isolation of EVs from large volumes of samples. When compared to ultracentrifugation (UC), which is the most widely used method to concentrate EVs, TFF is a more efficient, scalable, and gentler method. Comparative assessment of TFF and UC of conditioned cell culture media revealed that the former concentrates EVs of comparable physicochemical characteristics, but with higher yield, less single macromolecules and aggregates (<15 nm in size), and improved batch-to-batch consistency in half the processing time (1 h). The TFF protocol was then successfully implemented on fluids derived from patient lipoaspirate. EVs from adipose tissue are of high clinical relevance, as they are expected to mirror the regenerative properties of the parent cells.


1996 ◽  
Vol 42 (2) ◽  
pp. 115-119 ◽  
Author(s):  
G. A. Saunders ◽  
J. G. Hancock

Chloride (≥ 0.1 mM) was essential for asexual and sexual reproduction, but not mycelial growth, by Pythium ultimum in synthetic culture media. Bromide partially substituted for chloride in support of oogonia formation. The production of gemmae (sporangia or hyphal swellings) increased in proportion to concentrations of KCl in culture media between 0.2 and about 0.5 mM but leveled off between 0.5 and 4 mM. Chloride contents of mycelia after 3 days incubation were proportional to the number of gemmae produced when the fungus was grown in low concentrations of KCl. Under the culture conditions of this study, production of oogonia and gemmae commenced in about 70 and 95 h, respectively, in complete media. When 0.2 mM KCl was added to cultures 95 h or older that were grown in chloride deficient media, oogonium or gemma production was initiated in 20–25 or 10–17 h, respectively. Germination of gemmae, mycelial growth (gain in dry matter), and culture pH were not influenced significantly by the chloride deficiences that prevented sexual and asexual reproduction.Key words: chloride requirement, soilborne plant pathogen, reproduction of fungi, sporangia, hyphal swellings.


2018 ◽  
Vol 37 (11) ◽  
pp. 770-779 ◽  
Author(s):  
Tabrej Khan ◽  
Mohamed Thariq Bin Hameed Sultan ◽  
Ahmad Hamdan Ariffin

In this review, previous studies about the properties and applications of natural fiber composites in the aerospace and automobile fields will be discussed. Natural fiber composites are a better alternate to the existing artificial fiber composites due to their advantages, e.g. lightweight, cheaper and, most importantly, their environmental aspects and biodegradability. Since ancient times, natural fibers have been used for preparing walls, baskets, ropes, clothes, and many more products. More recently, natural fibers such as jute, kenaf, sisal, hemp, and flax have been used in the engineering production field. Natural fiber composites are used increasingly in the aerospace and automotive industries. Nowadays, natural fiber composites and artificial composites are being compared by researchers to find the most appropriate materials for engineering fields. Researchers are also more focused on natural fibers due to their biodegradability and low production cost. Assessments of the materials used in aircraft parts and panel structures have been made to study the potential of using natural fiber composites instead.


2018 ◽  
Vol 48 (1) ◽  
pp. 76-87 ◽  
Author(s):  
Maria Rita Alaniz Porto ◽  
Vivian Sayuri Okina ◽  
Tatiana Colombo Pimentel ◽  
Sandra Garcia ◽  
Sandra Helena Prudencio

Purpose The purpose of this study was to evaluate beet and orange mixed juices added with lyophilized Lactobacillus acidophilus probiotic culture. Design/methodology/approach Two formulations of probiotic beet and orange mixed juices (1:1 e 1:2 v/v) were prepared, stored at 4°C for 28 days and were evaluated for probiotic survival, physicochemical stability, antioxidant activity and sensory acceptance. The probiotic culture was added in a lyophilized form and was not propagated in culture media or juice. Findings Physicochemical characteristics (pH, titratable acidity, total soluble solids and color) and antioxidant activity showed no undesirable alterations during storage. The number of probiotics followed established minimum requirement for probiotic foods (109 CFU/200mL) during the 28 days of storage. The juices showed good sensory acceptance and purchase intention, especially regarding the color of the product. Practical implications The beet and orange mixed juices are suitable carriers for L. acidophilus with a shelf life of at least 28 days at 4°C. Originality/value Direct addition of the probiotic culture could result in high probiotic survival in mixed juices, dispensing the propagation step.


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