Search Results (40)

Optical fiber Raman and surface-enhanced Raman scattering (SERS) probes hold great promise for in vivo biosensing and in situ monitoring of hostile environments. However, the silica Raman scattering background generated within the optical fiber increases in proportion to the length of the fiber, and it can swamp the signal from the target analyte. While filtering can be applied at the distal end of the fiber, the use of bulk optical elements has limited probe miniaturization to a diameter of 600 µm, which in turn limits the potential applications. To overcome this limitation, femtosecond laser micromachining was used to fabricate a prototype micro-optical filter, which was directly integrated on the tip of a 125 µm diameter double-clad fiber (DCF) probe. The outer surface of the microfilter was further modified with a nanostructured, SERS-active, plasmonic film that was used to demonstrate proof-of-concept performance with thiophenol as a test analyte. With further optimization of the associated spectroscopic system, this ultra-compact microprobe shows great promise for Raman and SERS optical fiber sensing. Full article

The application of low-pressure nanofiltration (NF) was investigated for three different applications: water reuse from acid mine drainage (AMD), surface water containing natural organic matter (NOM) and agricultural reuse of microfiltered biologically treated sewage effluent (MF-BTSE). AMD contains many valuable rare earth elements (REEs) and copper (Cu) that can be recovered with fresh water. The NF90 membrane was investigated for recovery of fresh water from synthetic AMD. A steady permeate flux of 15.5 ± 0.2 L/m²h was achieved for pretreated AMD with over 98% solute rejection. NF90 achieved a high dissolved organic carbon (DOC) rejection of 95% from surface water containing NOM where 80% of the organic fraction was hydrophilic, mainly humics. The NF process maintained a high permeate flux of 52 LMH at 4 bars. The MF-BTSE was treated by NTR-729HF for agricultural reuse. NTR-729HF membranes were capable of rejecting DOC and inorganics such as sulfates and divalent ions (SO₄²⁻, Ca²⁺ and Mg²⁺) from MF-BTSE, with less than 20% rejection of monovalent (Na⁺ and Cl⁻) ions. The sodium adsorption ratio (SAR) was significantly reduced from 39 to 14 after treatment through NTR-729HF at 4 bar. The resulting water was found to be suitable to irrigate salt-sensitive crops. Full article

The present work aimed to use cocoa pod husk (CPH) and its extracted pectin as a potential substrate for the production of pectinase and to test the enzyme produced in the clarification process of apple juice. CPH with a particle size of <0.84 mm was employed for pectinase production by a selected strain of Aspergillus niger NRRL 2270. The optimization of the physicochemical conditions of the production medium led to an enzymatic activity of 602.03 U/g dry CPH, which was obtained under the following conditions: 110.25 g/L of CPH, 5% w/v pectin extract, 0.05 g/L of yeast extract, incubation at 28 °C, and pH 4, representing a 176% increase in enzymatic activity under the evaluated conditions. The production kinetics of pectinase showed maximum enzymatic activity at 96 h. Subsequently, the enzymatic extract was precipitated, microfiltered, and ultrafiltrated, resulting in 4852.50 U/mg of specific activity. The enzymatic activity after recovery and purification processes corresponded to 819 U/g dry CPH. Finally, a clarification stage of apple juice was carried out, in which the produced pectinase (CauPec) showed turbidity of 448.89 NTU compared to 417.89 NTU for the commercial enzyme and a viscosity of 1.86 cP, CauPec, and 1.19 cP, commercial pectinase, as well as soluble solids of 8.0 for commercial pectinase and 8.73 for CauPec. Therefore, it can be concluded that CPH and its pectin extract were excellent substrates for the production of pectinases, whose formulation is highly stable and can be applied in the clarification of apple juice. Full article

The bulk of research on microfiltered seawater (SW) is based on its short-term effects. However, the long-term physiological adaptations to combining SW and resistance training (RT) are unknown. This study aimed to analyse the impact of an RT program using elastic bands combined with SW intake on hepatic biomarkers, inflammation, oxidative stress, and blood pressure in post-menopausal women. Ninety-three women voluntarily participated (age: 70 ± 6.26 years; body mass index: 22.05 ± 3.20 kg/m²; Up-and-Go Test: 6.66 ± 1.01 s). RT consisted of six exercises (32 weeks, 2 days/week). Nonsignificant differences were reported for hepatic biomarkers except for a reduction in glutamic-pyruvic transaminase (GPT) in both RT groups (RT + SW: p = 0.003, ES = 0.51; RT + Placebo: p = 0.012, ES = 0.36). Concerning oxidative stress, vitamin D increased significantly in RT + SW (p = 0.008, ES = 0.25). Regarding inflammation, interleukin 6 significantly decreased (p = 0.003, ES = 0.69) in RT + SW. Finally, systolic blood pressure significantly decreased in both RT groups (RT + placebo: p < 0.001, ES = 0.79; RT + SW: p < 0.001, ES = 0.71) as did diastolic blood pressure in both SW groups (RT + SW: p = 0.002, ES = 0.51; CON + SW: p = 0.028, ES = 0.50). Therefore, RT + SW or SW alone are safe strategies in the long term with no influences on hepatic and oxidative stress biomarkers. Additionally, SW in combination with RT positively influences vitamin D levels, inflammation, and blood pressure in older women. Full article

Gas chromatography–mass spectrometry (GC–MS), physicochemical and microbiological analyses, sensory descriptive evaluation, and multivariate analyses were applied to evaluate the efficiencies of microfiltration and pasteurization processes during the shelf life of beer. Samples of microfiltered and pasteurised beer were divided into fresh and aged groups. A forced ageing process, which consisted of storing fresh samples at 55° C for 6 days in an incubator and then keeping them under ambient conditions prior to analysis, was applied. Physicochemical analysis showed that both microfiltered and pasteurised samples had a slight variation in apparent extract, pH, and bitterness. The samples that underwent heat treatment had lower colour values compared with those that were microfiltered. Chromatographic peak areas of vicinal diketones increased in both fresh and aged samples. The results of the microbiological analysis revealed spoilage lactic acid bacteria (Lactobacillus) and yeasts (Saccharomyces and non-Saccharomyces) in fresh microfiltered samples. In the GC–MS analysis, furfural, considered by many authors as a heat indicator, was detected only in samples that underwent forced ageing and not in samples that were subjected to thermal pasteurisation. Finally, sensory analysis found differences in the organoleptic properties of fresh microfiltered samples compared with the rest of the samples. Full article

This investigation aimed to assess how the somatic cell count (SCC) impacts milk production and the physicochemical quality of milk, including the effects of centrifugation and microfiltration on SCCs and the yield of fresh cheese. Milk production was analysed at different somatic cell counts (SCCs) to observe how centrifugation and microfiltration affected the removal of SCs from the milk and the yield of fresh cheese. Tukey’s test was employed at a 5% significance level to compare the chemical composition of the milk, milk production, and fresh cheese yield when using microfiltered and/or centrifuged milk. Milk with an SCC of ≤200,000 somatic cells (SCs) per mL exhibited higher yields. Although centrifugation and microfiltration influenced milk fat content, total dry extract and SCC, they did not impact fresh cheese yield. It is important to note that these processes reduced the fat content and SCC, making skim milk a potential option for future research studies. Full article

Recently, there has been a significant focus on the issue of pollution caused by livestock and poultry rearing, which is recognized as a prominent contributor to nonpoint source pollution in the agricultural sector. This study employed the life cycle assessment (LCA) methodology to evaluate the environmental impact of several pig manure processing scenarios with the aim of determining the appropriate solid–liquid separation tool for large-scale pig farms. The findings indicate that the utilization of a screw extruder for solid–liquid separation in Scenario 2 has a lower environmental impact. In contrast to Scenario 1, Scenario 2 exhibits reduced environmental potential in the areas of global warming, human toxicity, acidification, and eutrophication. Specifically, the global warming, human toxicity, acidification, and eutrophication impacts decreased by 56%, 81%, 83%, and 273%, respectively, due to the implementation of solid–liquid separation. The type of solid–liquid separation equipment used during the processing of swine manure, as well as the subsequent treatment, have a significant impact on environmental emissions. Compared to Scenario 2, Scenario 3, which utilizes a centrifugal microfilter for solid–liquid separation, exhibits a lower environmental impact in terms of human toxicity, resulting in a reduction of 0.736 kg DCB-eq. In general, solid–liquid separation is a viable and environmentally friendly method for the disposal of waste from large-scale pig farms. The adoption of this method is highly recommended. During its implementation, careful consideration should be given to factors such as separation efficiency and pollution emissions. It is crucial to select appropriate equipment for solid–liquid separation to effectively process the waste. Full article

Six different TiO₂/CNT nanocomposite-coated polyvinylidene-fluoride (PVDF) microfilter membranes (including –OH or/and –COOH functionalized CNTs) were evaluated in terms of their performance in filtering oil-in-water emulsions. In the early stages of filtration, until reaching a volume reduction ratio (VRR) of ~1.5, the membranes coated with functionalized CNT-containing composites provided significantly higher fluxes than the non-functionalized ones, proving the beneficial effect of the surface modifications of the CNTs. Additionally, until the end of the filtration experiments (VRR = 5), notable flux enhancements were achieved with both TiO₂ (~50%) and TiO₂/CNT-coated membranes (up to ~300%), compared to the uncoated membrane. The irreversible filtration resistances of the membranes indicated that both the hydrophilicity and surface charge (zeta potential) played a crucial role in membrane fouling. However, a sharp and significant flux decrease (~90% flux reduction ratio) was observed for all membranes until reaching a VRR of 1.1–1.8, which could be attributed to the chemical composition of the oil. Gas chromatography measurements revealed a lack of hydrocarbon derivatives with polar molecular fractions (which can act as natural emulsifiers), resulting in significant coalescent ability (and less stable emulsion). Therefore, this led to a more compact cake layer formation on the surface of the membranes (compared to a previous study). It was also demonstrated that all membranes had excellent purification efficiency (97–99.8%) regarding the turbidity, but the effectiveness of the chemical oxygen demand reduction was slightly lower, ranging from 93.7% to 98%. Full article

Lactic acid (LA) is an important chemical material facing rapid demand in recent years. The oriented fermentation of kitchen waste is a promising route for economic LA production. However, the refinement of LA from fermentation broth is a spiny issue. In this study, the performance of ultrafiltration (UF) process for the refinement of LA from the pre-microfiltered broth of kitchen waste fermentation was first investigated. The results showed that with 50 KDa polyethersulfone membrane, under the optimum pressure of 120 KPa, the pH of 6.0, and the backflushing mode with the deionized water for 3 min, the best performance was achieved with the chroma removal efficiency, turbidity removal efficiency, protein removal efficiency and total sugar removal efficiency of 54.3%, 89.8%, 71.7% and 58.5%, respectively, and LA recovery efficiency was 93.6%. The results indicated that the UF process could further effectively refine the pre-microfiltered broth of kitchen waste fermentation, and the combination of microfiltration and UF process is ideal for achieving desirable LA refinement performance. This study verified the feasibility of UF process in LA refinement from pre-microfiltered broth of kitchen waste fermentation, and based on the results, the further exploration of proper post-process to treat UF filtrate for obtaining LA product with higher quality should be explored in the future. Full article

The aim was to explore the effects of a 32-week resistance training (RT) intervention with elastic bands with or without microfiltered seawater (SW) supplementation on isokinetic strength, bone mineral density (BMD), body composition, and subjective quality of life in postmenopausal women. Ninety-three untrained women (age: 70.00 ± 6.26 years; body mass index: 22.05 ± 3.20 kg/m²; body fat: 37.77 ± 6.38%; 6.66 ± 1.01 s up-and-go test) voluntarily participated in this randomized, double-blinded, controlled trial. Participants were allocated into four groups (RT+SW, RT+PLA, CON+SW, and CON+PLA). The RT intervention (twice weekly) consisted of different exercises for the whole body performed at submaximal intensities with elastic bands. Both control groups were not involved in any exercise program. A two-way mixed analysis of variance of repeated measures revealed significant improvements in almost all the variables in both intervention groups (p < 0.05). However, significant differences with controls were encountered in isokinetic strength, body fat percentage, and bodily pain. Although the group with SW supplementation obtained greater effect sizes, non-significant differences between both RT groups were observed. In conclusion, the determinant factor of the adaptations seems to be RT rather than SW. Full article

Pretreatment of reverse osmosis (RO) feed water of high mineral scaling propensity was evaluated with respect to downstream RO membrane scaling, for two different feed pretreatment configurations. The pretreatment schemes included (i) media sand filtration, followed by a hydrocyclone (HC) and (ii) a hydrocyclone, microfilter, and a UF module, where both configurations included mesh screens for added protection. The first pretreatment configuration reduced the source water turbidity to ~0.5 NTU, while treatment that included UF feed yielded turbidity of $\underset{˜}{<}0.1\mathrm{NTU}$; both pretreatment strategies provided feed water turbidity within the range recommended for RO desalination. Membrane scaling tests, with the pretreated water without antiscalant dosing, using a plate-and-frame RO unit and a membrane monitoring system, provided real-time membrane surface images that were quantified with respect to the progression of mineral scaling. RO desalting of source water pretreated with the first configuration revealed flux decline that was 75% greater and scale coverage (primarily gypsum) a factor of approximately eight higher relative to desalting of UF-treated source water. The results suggest that RO desalting of high mineral scaling propensity water can significantly benefit from added UF treatment to achieve feedwater turbidity to well below the typically recommended 0.5 NTU upper limit. Full article

Microtube microfilter with organic phosphoric acid (expressed as MF-OP) containing a wastewater portion with buffer fluid and an enriched portion with nitric acid fluid and organic phosphoric extractant dissolved in benzin has been studied for its trivalent holmium (expressed as Ho(III) collection from rare earth wastewater. Common parameters affecting the collection effect have been investigated, including hydrogen ion molar concentration (molar concentration can be expressed as Cm) or pH value, initial concentration (expressed as Co) of Ho(III), ion-force of rare earth wastewater, voluminal proportion of organic phosphoric extractant with benzin and nitric acid fluid (expressed as Vr), nitric acid Cm, extractant Cm, and type of acid fluid in an enriched portion. The virtues of MF-OP compared to the traditional collection was explored. The impacts of hydrodynamic characteristics (steadiness and current speed) and MF parameter factors (inradius of tube, tube–shell thickness, proportion of holes) on the collection performance of MF-OP for Ho(III) collection were also considered. The test results displayed that the greatest collection conditions of Ho(III) were attained as nitric acid Cm was 4.00 mol/L, extractant Cm was 0.220 mol/L, and Vr was 0.8 in the enriched portion, and pH value was 4.60 in the wastewater portion. Ion- force of rare earth wastewater had no noticeable outcome on Ho(III) collection. The collection proportion of Ho(III) was attainable to 93.1% in 280 min, while Co was 1.80 × 10⁻³ mol/L. Full article

Olive mill wastewater (OMWW) represents a by–product but also a source of biologically active compounds, and their recycling is a relevant strategy to recover income and to reduce environmental impact. The objective of the present study was to obtain a new functional beverage with a health–promoting effect starting from OMWW. Fresh OMWW were pre–treated through filtration and/or microfiltration and subjected to fermentation using strains belonging to Lactiplantibacillus plantarum, Candida boidinii and Wickerhamomyces anomalus. During fermentation, phenolic content and hydroxytyrosol were monitored. Moreover, the biological assay of microfiltered fermented OMWW was detected versus tumor cell lines and as anti-inflammatory activity. The results showed that in microfiltered OMWW, fermentation was successfully conducted, with the lowest pH values reached after 21 days. In addition, in all fermented samples, an increase in phenol and organic acid contents was detected. Particularly, in samples fermented with L. plantarum and C. boidinii in single and combined cultures, the concentration of hydroxytyrosol reached values of 925.6, 902.5 and 903.5 mg/L, respectively. Moreover, biological assays highlighted that fermentation determines an increase in the antioxidant and anti–inflammatory activity of OMWW. Lastly, an increment in the active permeability on Caco-2 cell line was also revealed. In conclusion, results of the present study confirmed that the process applied here represents an effective strategy to achieve a new functional beverage. Full article

The aim of this clinical study was to demonstrate that through a micrograft of viable adipose tissue cells microfiltered at 50 microns to exclude fibrous shoots and cell debris in a suspension of cross-linked hyaluronic acid, we were able to improve visible imperfections of the dermis and to improve clinically observable wrinkles, with a beneficial effect also in the extracellular matrix (ECM). Background and Objectives: With the passage of time, the aging process begins, resulting in a progressive impairment of tissue homeostasis. The main reason for the formation of wrinkles is the involution of the papillary dermis, as well as the loss of stem cell niches with compromise of the extra-cytoplasmic matrix (ECM), and the loss of hyaluronic acid, which helps to maintain the shape and resistance and that is contained in the connective tissue. Materials and Methods: This study involved 14 female patients who underwent dermal wrinkle correction and bio-regeneration over the entire facial area through a suspension containing 1.0 mL of viable micrografts from adipose tissue in a 1.0 mL cross-linked hyaluronic acid. To verify the improvement of the anatomical area concerned over time, the various degrees of correction obtained for wrinkles, and in general for texture, were objectively evaluated by using a Numeric Rating scale (NRS) 10–0, a modified Vancouver scale and a Berardesca scale. Results: The Berardesca, NRS and Modified Vancouver scales showed that with this technique it was possible to obtain excellent results both when the suspension was injected into wrinkles with the linear retrograde technique, and when it was injected with the micropomphs technique to correct furrows, with the intent to revitalize the tissue through progenitors with adult stemness markers. Conclusions: The combination of microfragmented and microfiltered adipose tissue and cross-linked hyaluronic acid at 50 microns is safe new method to treat soft tissue defects such as deep wrinkles. Full article

Dual membrane hybrid systems generally produce reclaimed water for non-potable uses by blending microfiltered biologically treated sewage effluent (BTSE) and reverse osmosis (RO) permeate. This reclaimed water is found to contain a significant amount of micro-pollutants, which possibly cause toxicity effects to aquatic organisms and plants when exposed to it. Therefore, removing such pollutants from the reclaimed water before reaching the community is highly emphasized nowadays. The currently used treatment of the RO treatment of microfiltered BTSE is energy intensive and not cost effective. This paper focuses on less costly and efficient membrane-based hybrid treatment systems such as the microfiltration-adsorption (MF-GAC) hybrid system, Nano filter (NF) and RO in the removal of micro-pollutants from the microfiltered BTSE. Both the MF-GAC hybrid system and NF (with NTR 729HF membrane) removed 70 to 95% of micropollutants from microfiltered BTSE. The removal depends on the hydrophobicity, charge, and size of the micropollutants. RO was excellent in removing more than 90% of pollutants, while MF was inefficient, as the latter primarily depends on the size exclusion mechanism. Based on the finding, it is suggested to treat only a portion of microfiltered BTSE through the MF-GAC or NF membrane before blending with RO permeate to enhance the removal of micro-pollutants from reclaimed water. The development of sustainable hybrid systems for the removal of all micropollutants of different chemical and physical properties is the key for the water reclamation. Full article