Ganoderma lucidum: Multifaceted mechanisms to combat diabetes through polysaccharides and triterpenoids: A comprehensive review

Diabetes is a chronic metabolic disorder. Diabetes complications can affect many organs and systems in the body. Ganoderma lucidum (G. lucidum) contains various compounds that have been studied for their potential antidiabetic effects, including polysaccharides, triterpenoids (ganoderic acids, ganoderol B), proteoglycans, and G. lucidum extracts. G. lucidum polysaccharides (GLPs) and triterpenoids have been shown to act through distinct mechanisms, such as improving glucose metabolism, modulating the mitogen-activated protein kinase (MAPK) system, inhibiting the nuclear factor-kappa B (NF-κB) pathway, and protecting the pancreatic beta cells. While GLPs exhibit a significant role in controlling diabetic nephropathy and other associated complications. This review states the G. lucidum antidiabetic mechanisms of action and potential biologically active compounds that contribute to diabetes management and associated complications. To make G. lucidum an appropriate replacement for the treatment of diabetes with fewer side effects, more study is required to completely comprehend the number of physiologically active compounds present in it as well as the underlying cellular mechanisms that influence their effects on diabetes.

Adsorptive removal of heavy metals from wastewater using Cobalt-diphenylamine (Co-DPA) complex

Heavy metals like Cadmium, Lead, and Chromium are the pollutants emitted into the environment through industrial development. In this work, a new diphenylamine coordinated cobalt complex (Co-DPA) has been synthesized and tested for its efficiency in removing heavy metals from wastewater, and its adsorption capacity was investigated. The effectiveness of heavy metals removal by Co-DPA was evaluated by adjusting the adsorption parameters, such as adsorbent dose, pH, initial metals concentration, and adsorption period. Heavy metal concentrations in real sample were 0.267, 0.075, and 0.125 mg/L for Cd2+, Pb2+, and Cr3+ before using as-synthesized Co-DPA to treat wastewater. After being treated with synthesized Co-DPA the concentration of heavy metals was reduced to 0.0129, 0.00028, 0.00054 mg/L for Cd2+, Pb2+, and Cr3+, respectively, in 80 min. The removal efficiency was 95.6%, 99.5%, and 99.5% for the respective metals. The adsorption process fitted satisfactorily with Freundlich isotherm with R2(0.999, 0.997, 0.995) for Cd2+, Pb2+, and Cr3+, respectively. The kinetic data obeyed the pseudo-second order for Cd2+ and Cr2+ and the pseudo-first order for Pb2+. Based on the results obtained within the framework of this study, it is concluded that the as-synthesized Co-DPA is a good adsorbent to eliminate heavy metal ions like Cd2+, Pb2+, and Cr3+from wastewater solution. In general, Co-DPA is a promising new material for the removal of heavy metal ions from water.

Binding Study of Antibacterial Drug Ciprofloxacin with Imidazolium-Based Ionic Liquids Having Different Halide Anions: A Spectroscopic and Density Functional Theory Analysis

Herein, we have shown the interaction of an antibiotic drug ciprofloxacin (CIP) with three surface-active ionic liquids (ILs), having the same cation and different anions, namely, 1-decyl-3-methylimidazoliumtetrafluoroborate [C10mim][BF4], 1-decyl-3-methylimidazolium bromide [C10mim][Br], and 1-decyl-3-methylimidazolium chloride [C10mim][Cl]. This study has been performed by exploiting various spectroscopic techniques such as steady-state fluorescence, time-resolved fluorescence, and UV-visible spectroscopy. The fluorescence emission study of CIP with ILs was performed at various concentrations of all the three ILs. The emission spectra of CIP decreased in the presence of ILs, suggesting complex formation between CIP-IL. The effect of different concentrations of ILs on the emission spectra of CIP was exploited in terms of quenching and binding parameters. Further, fluorescence emission study was validated by the time-resolved fluorescence technique by measuring the average lifetime (τavg) of CIP in the presence of all the three ILs. The τavg value of the drug changed with the addition of ILs, which suggests complex formation between the drug and ILs. This complex formation was also confirmed by UV-visible spectroscopy results of CIP with all the three ILs. Further, for evaluating the thermodynamic parameters of the CIP-IL interactions, isothermal titration calorimetry (ITC) was performed. The ITC experiment yielded the thermodynamic parameters, ΔH (change in the enthalpy of association), ΔG (Gibbs free energy change), ΔS (entropy change), and binding constant (Ka). The binding parameters driven by ITC revealed that CIP-IL interactions are spontaneous in nature and enthalpy-driven, involving hydrophobic forces. Further, the classical density functional theory (DFT) calculations were performed, which provided deep insight for CIP-IL complex formation.

A systematic assessment of matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) application for rapid identification of pathogenic microbes that affect food crops: delivered and future deliverables

MALDI-TOF MS has decades of experience in the detection and identification of microbial pathogens. This has now become a valuable analytical tool when it comes to the identification and detection of clinical microbial pathogens. This review gives a brief synopsis of what has been achieved using MALDI-TOF MS in clinical microbiology. The major focus, however, is on summarizing and highlighting the effectiveness of MALDI-TOF MS as a novel tool for rapid identification of food crop microbial pathogens. The methods used and the sample preparation methodologies reported thus far have been highlighted and the challenges and gaps and recommendations for fine tuning the technique have been put forth. In an era where anything close to the health and welfare of humanity has been considered as the top priority, this review pitches on one such relevant research topics.

Green Synthesis of Silver Nanoparticles Using Acacia ehrenbergiana Plant Cortex Extract for Efficient Removal of Rhodamine B Cationic Dye from Wastewater and the Evaluation of Antimicrobial Activity

Silver nanoparticles (Ag-NPs) exhibit vast potential in numerous applications, such as wastewater treatment and catalysis. In this study, we report the green synthesis of Ag-NPs using Acacia ehrenbergiana plant cortex extract to reduce cationic Rhodamine B (RhB) dye and for antibacterial and antifungal applications. The green synthesis of Ag-NPs involves three main phases: activation, growth, and termination. The shape and morphologies of the prepared Ag-NPs were studied through different analytical techniques. The results confirmed the successful preparation of Ag-NPs with a particle size distribution ranging from 1 to 40 nm. The Ag-NPs were used as a heterogeneous catalyst to reduce RhB dye from aqueous solutions in the presence of sodium borohydride (NaBH₄). The results showed that 96% of catalytic reduction can be accomplished within 32 min using 20 μL of 0.05% Ag-NPs aqueous suspension in 100 μL of 1 mM RhB solution, 2 mL of deionized water, and 1 mL of 10 mM NaBH₄ solution. The results followed a zero-order chemical kinetic (R² = 0.98) with reaction rate constant k as 0.059 mol L^-1 s^-1. Furthermore, the Ag-NPs were used as antibacterial and antifungal agents against 16 Gram-positive and Gram-negative bacteria as well as 1 fungus. The green synthesis of Ag-NPs is environmentally friendly and inexpensive, as well as yields highly stabilized nanoparticles by phytochemicals. The substantial results of catalytic reductions and antimicrobial activity reflect the novelty of the prepared Ag-NPs. These nanoparticles entrench the dye and effectively remove the microorganisms from polluted water.

Nanocomposite Electrocatalysts for Hydrogen Evolution Reactions (HERs) for Sustainable and Efficient Hydrogen Energy-Future Prospects

Hydrogen is considered a good clean and renewable energy substitute for fossil fuels. The major obstacle facing hydrogen energy is its efficacy in meeting its commercial-scale demand. One of the most promising pathways for efficient hydrogen production is through water-splitting electrolysis. This requires the development of active, stable, and low-cost catalysts or electrocatalysts to achieve optimized electrocatalytic hydrogen production from water splitting. The objective of this review is to survey the activity, stability, and efficiency of various electrocatalysts involved in water splitting. The status quo of noble-metal- and non-noble-metal-based nano-electrocatalysts has been specifically discussed. Various composites and nanocomposite electrocatalysts that have significantly impacted electrocatalytic HERs have been discussed. New strategies and insights in exploring nanocomposite-based electrocatalysts and utilizing other new age nanomaterial options that will profoundly enhance the electrocatalytic activity and stability of HERs have been highlighted. Recommendations on future directions and deliberations for extrapolating information have been projected.

Noble Metals Deposited LaMnO3 Nanocomposites for Photocatalytic H2 Production

Due to the growing demand for hydrogen, the photocatalytic hydrogen production from alcohols present an intriguing prospect as a potential source of low-cost renewable energy. The noble metals (Ag, Au, Pd and Pt) deposited LaMnO₃ nanocomposites were synthesized by a non-conventional green bio-reduction method using aqueous lemon peel extract, which acts as both reducing and capping agent. The successful deposition of the noble metals on the surface of LaMnO₃ was verified by using powder XRD, FTIR, TEM, N₂-physisorption, DR UV-vis spectroscopy, and XPS techniques. The photocatalytic activity of the synthesized nanocomposites was tested for photocatalytic H₂ production under visible light irradiation. Different photocatalytic reaction parameters such as reaction time, pH, catalyst mass and reaction temperature were investigated to optimize the reaction conditions for synthesized nanocomposites. Among the synthesized noble metal deposited LaMnO₃ nanocomposites, the Pt-LaMnO₃ nanocomposite offered superior activity for H₂ production. The enhanced photocatalytic activity of the Pt-LaMnO₃ was found as a result from low bandgap energy, high photoelectrons generation and enhanced charge separation due to deposition of Pt nanoparticles. The effective noble metal deposition delivers a new route for the development of plasmonic noble metal-LaMnO₃ nanocomposites for photocatalytic reforming of aqueous methanol to hydrogen.

Green Synthesis of Zinc Oxide Nanoparticles Using Salvia officinalis Leaf Extract and Their Photocatalytic and Antifungal Activities

The facile bio-fabrication of zinc oxide (ZnO) nanoparticles (NPs) is described in this study using an aqueous leaf extract of Salvia officinalis L. as an efficient stabilizing/capping agent. Biosynthesis of nanomaterials using phytochemicals present in the plants has received great attention and is gaining significant importance as a possible alternative to the conventional chemical methods. The properties of the bio-fabricated ZnONPs were examined by different techniques, such as UV-visible spectroscopy, X-ray diffraction spectroscopy (XRD), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and thermogravimetric/differential scanning calorimetry analysis (TGA/DTG). The photocatalytic activity of ZnONPs was investigated against methyl orange (MO) under UV light irradiation. Under optimum experimental conditions, ZnONPs exhibited 92.47% degradation of MO. Furthermore, the antifungal activity of bio-fabricated ZnONPs was determined against different clinical Candida albicans isolates following standard protocols of broth microdilution and disc diffusion assay. The susceptibility assay revealed that ZnONPs inhibit the growth of all the tested fungal isolates at varying levels with MIC values ranging from 7.81 to 1.95 µg/mL. Insight mechanisms of antifungal action appeared to be originated via inhibition of ergosterol biosynthesis and the disruption of membrane integrity. Thus, it was postulated that bio-fabricated ZnONPs have sustainable applications in developing novel antifungal agents with multiple drug targets. In addition, ZnONPs show efficient photocatalytic efficiency without any significant catalytic loss after the catalyst was recycled and reused multiple times.

Nanochitosan: Commemorating the Metamorphosis of an ExoSkeletal Waste to a Versatile Nutraceutical

Chitin (poly-N-acetyl-D-glucosamine) is the second (after cellulose) most abundant organic polymer. In its deacetylated form-chitosan-becomes a very interesting material for medical use. The chitosan nano-structures whose preparation is described in this article shows unique biomedical value. The preparation of nanochitosan, as well as the most vital biomedical applications (antitumor, drug delivery and other medical uses), have been discussed in this review. The challenges confronting the progress of nanochitosan from benchtop to bedside clinical settings have been evaluated. The need for inclusion of nano aspects into chitosan research, with improvisation from nanotechnological inputs has been prescribed for breaking down the limitations. Future perspectives of nanochitosan and the challenges facing nanochitosan applications and the areas needing research focus have been highlighted.

Crustacean Waste-Derived Chitosan: Antioxidant Properties and Future Perspective

Chitosan is obtained from chitin that in turn is recovered from marine crustacean wastes. The recovery methods and their varying types and the advantages of the recovery methods are briefly discussed. The bioactive properties of chitosan, which emphasize the unequivocal deliverables contained by this biopolymer, have been concisely presented. The variations of chitosan and its derivatives and their unique properties are discussed. The antioxidant properties of chitosan have been presented and the need for more work targeted towards harnessing the antioxidant property of chitosan has been emphasized. Some portions of the crustacean waste are being converted to chitosan; the possibility that all of the waste can be used for harnessing this versatile multifaceted product chitosan is projected in this review. The future of chitosan recovery from marine crustacean wastes and the need to improve in this area of research, through the inclusion of nanotechnological inputs have been listed under future perspective.

Lightweight Smart Autofocusing Eyeglasses

More than 100 million people in the United States of America alone suffer from age-related presbyopia caused by a loss of focal accommodation of the eye crystalline lens as the lens stiffens with age. The resulting accommodative error or lag produces blurred images of objects placed at different distances. Conventional fixed uniform or graded power eyeglasses cannot provide accommodation thus resulting in significant visual impairment. In this paper we will discuss the implementation of lightweight auto-focusing eyeglasses that augment the accommodative range thus partially or fully restoring normal vision function. The paper discusses some aspects of the construction of tunable power eyepieces and the implementation of accommodation correction algorithms.

Marital separation among some poor Bangladeshi women: Analysis of some cases

Objective

This paper intends to show the challenges faced by poor Bangladeshi Muslim women from lower socioeconomic status, in case of divorce or separation in marriage. Participants will also learn how they earn for their living and how they raise their children if any. This paper will also present the obligations of marriage in Islam, which may reduce the hazards in their life.

Method

Some women were interviewed from lower socioeconomic status from slum area of Dhaka. Researcher took their consent before interview had started. They were asked about their age, educational status, duration of marriage, type of work they do for livelihood, whether they get any maintenance money from the husbands in case of separation, expenses for raising children if any, any criticize from the friends and relatives, etc. The answers were noted carefully.

Results

After critical analysis of the interview it was revealed that they were leading their lives on their own, most of them were not aware of their rights relating to marriage in Islam. Two of the women had to pay dowry. Some of them were addicted to tobacco leaf taken with betel nut and PAN, a special form of leaf.

Conclusions

In conclusion, it can be said that these women lead their lives with courage. They need to be educated about their marriage rights in Islam and legal help. At a time, men should be educated about the marriage rights of the wives and the evil effects of dowry in the society.

Disclosure of interest

The author has not supplied his/her declaration of competing interest.

Genetic analysis and identification of SSR markers associated with rice blast disease in a BC2F1 backcross population

Rice (Oryza sativa L.) blast disease is one of the most destructive rice diseases in the world. The fungal pathogen, Magnaporthe oryzae, is the causal agent of rice blast disease. Development of resistant cultivars is the most preferred method to achieve sustainable rice production. However, the effectiveness of resistant cultivars is hindered by the genetic plasticity of the pathogen genome. Therefore, information on genetic resistance and virulence stability are vital to increase our understanding of the molecular basis of blast disease resistance. The present study set out to elucidate the resistance pattern and identify potential simple sequence repeat markers linked with rice blast disease. A backcross population (BC₂F₁), derived from crossing MR264 and Pongsu Seribu 2 (PS2), was developed using marker-assisted backcross breeding. Twelve microsatellite markers carrying the blast resistance gene clearly demonstrated a polymorphic pattern between both parental lines. Among these, two markers, RM206 and RM5961, located on chromosome 11 exhibited the expected 1:1 testcross ratio in the BC₂F₁ population. The 195 BC₂F₁ plants inoculated against M. oryzae pathotype P7.2 showed a significantly different distribution in the backcrossed generation and followed Mendelian segregation based on a single-gene model. This indicates that blast resistance in PS2 is governed by a single dominant gene, which is linked to RM206 and RM5961 on chromosome 11. The findings presented in this study could be useful for future blast resistance studies in rice breeding programs.

Biofabrication of Fe nanoparticles in aqueous extract of Hibiscus sabdariffa with enhanced photocatalytic activities

Hibiscus sabdariffa is a strongly basic dye with a large number of medicinal applications and is used for various diagnostic purposes.

Large protein analysis of Staphylococcus aureus and Escherichia coli by MALDI TOF mass spectrometry using amoxicillin functionalized magnetic nanoparticles

Bacteria or their protein and peptide entity enrichment using biomolecules-functionalized magnetic nanoparticles, and analysis by matrix assisted laser desorption/ionization mass spectrometry (MALDI MS) is a promising technique to analyze microorganisms. High and low molecular weight proteins like penicillin-binding proteins are responsible for final step synthesis of peptidoglycan biosynthesis; those are the target of lactam antibiotics. In this paper, we synthesized magnetic nanoparticles (mag-NPs) and further modified them with 3-aminopropyltriethoxysilane, and then the β-lactam antibiotic amoxicillin was covalently linked to their surface. β-Lactam group attributes as penicillin binding proteins (PBPs) in bacteria. Staphylococcus aureus and Escherichia coli were used as model bacteria for enrichment based on the β-lactam affinity of magnetic nanoparticles, and then the bacteria were easily separated by an external magnet. Several high molecular weight penicillin binding proteins (PBPs) were detected by MALDI MS containing 10(4) and 10(3) colony-forming unit (cfu) per milileter (mL) of S. aureus and E. coli, respectively. In the case of E. coli, higher molecular weight PBPs were observed at 20 to 55 kDa in MALDI mass spectra. However, S. aureus bacteria resulted with femAB operon-based proteins, with molecular weight of 49570.4 Da, by MALDI MS after using amoxicillin functionalized-mag-NPs. The current approach provides an effective bacteria detection and preconcentration method that has high potential in the near future for fast and sensitive diagnosis of pathogenic bacteria infection. Graphical Abstract Schematic for large proteins analysis by MALDI TOF MS (a) mag-NPs and bacterial interaction (b) Penicillin binding proteins trapping by Amox-mag-NPs.

CoFe2 O4 -ZnO nanoparticles for rapid microwave-assisted tryptic digestion of phosphoprotein and phosphopeptide analysis by matrix-assisted laser desorption/ionization mass spectrometry

RATIONALE

Phosphorylation is a post-translational modification of proteins that plays very important role in a large number of biological processes. However, despite recent advancements in phosphoproteome research, large-scale detection and characterization of phosphopeptides by mass spectrometry (MS) is still a challenging task due to the low abundance of phosphopeptides and sub-stoichiometric nature of phosphorylation sites. On-particle microwave-assisted trypsin digestion of phosphoproteins and enrichment of phosphopeptides is an effective method for identification/characterization of phosphopeptides. Magnetic nanoparticles typically can absorb microwave radiation and generate heat in order to resolve complex phosphproteins and to enhance the digestion rate and capture the phosphopeptides on their modified surfaces.

METHODS

In this study, we used a cheap and efficient method for rapid microwave-assisted tryptic digestion of phosphoproteins and simultaneous enrichment of phosphopeptides using CoFe2 O4 -ZnO magnetic nanoparticles. Using this technique, the digestion time of phosphoproteins can be reduced and the phosphopeptides can be quickly analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). For the first time, we have applied CoFe2 O4 -ZnO magnetic nanoparticles for enrichment of phosphopeptides from standard phosphoproteins (β-casein and ovalbumin), complex samples (human serum and egg white) and a protein mixture of β-casein and BSA (1:100).

RESULTS

Our results demonstrate that the capture efficiency of CoFe2 O4 -ZnO nanoparticles for β-casein and ovalbumin in MALDI-TOFMS is very high (detection limits 0.2 fmol and 20 fmol, respectively). The CoFe2 O4 -ZnO nanoparticles have high affinity for phosphopeptide enrichment for β-casein in complex mixtures with BSA at 1:10 and 1:100 molar ratios in the microwave within 30 s.

CONCLUSIONS

Compared with other reported magnetic nanoparticles, the CoFe2 O4 -ZnO nanoparticles are easy to prepare and handle, and can save time in the phosphopeptide enrichment procedure, making these nanoparticle a good choice for highly sensitive phosphopeptide enrichment. Copyright © 2016 John Wiley & Sons, Ltd.

Environmental endocrine disruptors: Effects on the human male reproductive system

Incidences of altered development and neoplasia of male reproductive organs have increased during the last 50 years, as shown by epidemiological data. These data are associated with the increased presence of environmental chemicals, specifically "endocrine disruptors," that interfere with normal hormonal action. Much research has gone into testing the effects of specific endocrine disrupting chemicals (EDCs) on the development of male reproductive organs and endocrine-related cancers in both in vitro and in vivo models. Efforts have been made to bridge the accruing laboratory findings with the epidemiological data to draw conclusions regarding the relationship between EDCs, altered development and carcinogenesis. The ability of EDCs to predispose target fetal and adult tissues to neoplastic transformation is best explained under the framework of the tissue organization field theory of carcinogenesis (TOFT), which posits that carcinogenesis is development gone awry. Here, we focus on the available evidence, from both empirical and epidemiological studies, regarding the effects of EDCs on male reproductive development and carcinogenesis of endocrine target tissues. We also critique current research methodology utilized in the investigation of EDCs effects and outline what could possibly be done to address these obstacles moving forward.

MALDI mass spectrometry for probing the anti- staphylococcal capability of TiO2nanoparticles via near-UV and laser irradiation

We report the use of MALDI-MS as an effective tool in investigating the anti-staphylococcal property of TiO₂nanoparticles under near-UV and for the first time also under laser irradiation.

A nano-patterned self assembled monolayer (SAM) rutile titania cancer chip for rapid, low cost, highly sensitive, direct cancer analysis in MALDI-MS

We developed a cancer chip by nano-patterning a highly sensitive SAM titanium surface capable of capturing and sensing concentrations as low as 10 cancer cells/mL from the environment by Matrix Assisted Laser Desorption and Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS). The current approach evades any form of pretreatment and sample preparation processes; it is time saving and does not require the (expensive) conventional MALDI target plate. The home made aluminium (Al) target holder cost, on which we loaded the cancer chips for MALDI-TOF MS analysis, is about 60 USD. While the conventional stainless steel MALDI target plate is more than 700 USD. The SAM surface was an effective platform leading to on-chip direct MALDI-MS detection of cancer cells. We compared the functionality of this chip with the unmodified titanium surfaces and thermally oxidized (TO) titanium surfaces. The lowest detectable concentration of the TO chip was 10(3) cells/mL, while the lowest detectable concentration of the control or unmodified titanium chips was 10(6) cells/mL. Compared to the control surface, the SAM cancer chip showed 100,000 times of enhanced sensitivity and compared with the TO chip, 1000 times of increased sensitivity. The high sensitivity of the SAM surfaces is attributed to the presence of the rutile SAM, surface roughness and surface wettability as confirmed by AFM, XRD, contact angle microscope and FE-SEM. This study opens a new avenue for the potent application of the SAM cancer chip for direct cancer diagnosis by MALDI-TOF MS in the near future.

Quantum dot applications endowing novelty to analytical proteomics

This review surveys all the state-of-art applications of quantum dots (QDs) in conventional and modern analytical methods in proteomic studies. A brief introduction of QDs and their properties is initially presented followed by outlining the application of QDs in fluorescence, MS, imaging, and cancer-based proteomics. The in-depth application of QDs in MALDI-MS and surface assisted laser desorption/ionization-MS has been elaborately discussed, summarizing the speculated mechanism behind the protein-QDs interactions during QD matrix applications leading to enhanced detection sensitivity.

Bacterial toxicity/compatibility of platinum nanospheres, nanocuboids and nanoflowers

For the first time, we have investigated the bacterial toxicity or compatibility properties of Pt nanoparticles (NPs) with different sizes (P1, P2, P3, P4 and P5). The bacterio-toxic or compatible properties of these five different sized Pt NPs with the clinical pathogen, Pseudomonas aeruginosa were explored by many analytical methods such as the conventional plate count method, matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS), fluorescence microscopy and fluorescence sensoring techniques. The results revealed that the 1-3 nm sized (P1 and P2) Pt NPs showed bacterio-toxic properties while the 4-21 nm (P3, P4 and P5) Pt NPs exhibited bacterio-compatible properties. This is the first study which reports the bacterial toxicity of Pt NPs. The information released from this study is significantly important to future clinical, medical, biological and biomedical applications of Pt NPs.

Rapid detection of haloarchaeal carotenoids via liquid-liquid microextraction enabled direct TLC MALDI-MS

For the first time, we demonstrate the use of TiO2 nanoparticles (NPs) for enhancing the carotenoid production by the extremophilic haloarchea, Haloferax mediterranei. TiO2 NPs at optimal concentration of 375 mg/L results in a 95% increase in the production of carotenoid pigment compared to the control (no TiO2 NPs). The carotenoid pigments extracted from TiO2 NPs treated H. mediterranei cells, were separated using thin layer chromatography (TLC). The separated carotenoid spots were subjected directly for MALDI MS detection. To limit the sample diffusion during matrix addition on TLC plates, a simple bordering mode was exercised. Using this method we were able to detect the pigments successfully using MALDI-MS, directly from TLC plates after separation. In addition, we also applied the Pt NPs capped with ODT via Liquid-liquid microextraction (LLME) for extracting the pigment molecules from the halobacteria in MALDI-MS. These novel NP approaches possess numerous advantages such as; rapidity, ease in synthesis, high sensitivity and low cost.

A comparative study on the mode of interaction of different nanoparticles during MALDI-MS of bacterial cells

We propose the benefits of preincubation during nanoparticle-assisted bacterial analysis, where the bacteria are grown along with the nanoparticles. We were able to obtain a two to ten fold enhancement of bacterial signals in 3 h compared to the generally used methodology followed in previous literature. The previous literature method required a long time (18 h) to obtain such an enhancement. We probe the interactions of two bacteria, Staphylococcus aureus and Pseudomonas aeruginosa, with Ag, NiO, Pt TiO(2) and ZnO nanoparticles via transmission electron microscopy, ultraviolet spectroscopy and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS). Based on these results, we propose a mechanism for interaction of these five nanoparticles with bacteria. Two mechanisms were observed for the interactions: (1) Mechanism A is proposed for the Pt and NiO NPs which functioned based on affinity for bacterial cells. (2) Mechanism B was proposed for the bactericidal NPs such as TiO(2), ZnO and Ag NPs. The results indicate that the success of the unmodified NPs in MALDI-MS bacterial studies lies in following the ideal protocol for incubation at the ideal concentrations.

Monitoring the heat stress response of Escherichia coli via NiO nanoparticle assisted MALDI-TOF mass spectrometry

The heat stress response of Escherichia coli at various temperatures has been investigated using NiO nanoparticles assisted MALDI-TOF-MS. Significant numbers of protein peaks were obtained in the presence of NiO NPs when the samples were incubated at various temperatures in comparison with the control E. coli suspension (10(7)cfu/mL). The 10 kDa chaperonin (groES) is the principal protein operating both for the protection of proteins from denaturation and in the assembly of newly synthesized proteins. During the heat stress response with NiO NPs, 10 kDa chaperonin (grosES) proteins were detected using MALDI-TOF MS. The viability of E. coli was checked on LB agar plates at different temperatures and time treatments. In the presence of NiO NPs, viability decreases drastically; this has been explored and correlated with the MALDI-TOF MS results. Further, surface morphological changes of E. coli at different temperatures were investigated with NiO NPs by transmission electron microscopy (TEM). The response of heat stress toward E. coli for generating more stable protein ions can be applied for bacterial detection under high temperature conditions from biological, clinical and environmental samples.

Rapid and direct detection of attomole adenosine triphosphate (ATP) by MALDI-MS using rutile titania chips

We report the rutile titania-based capture of ATP and its application as a MALDI-MS target plate. This chip, when immersed in solutions containing different concentrations of ATP, can capture ATP and lead to its successful detection in MALDI-MS. We have optimized the ideal surface, showing an increased capture efficacy of the 900 °C (rutile) titania surfaces. We demonstrate the use of this chip as a target plate for direct analysis of the attached ATP using MALDI-MS, down to attomolar concentrations. This chip has a promising future for the detection of ATP in environmental samples, which may eventually be used as a pollution indicator in particular environments.

Rapid, sensitive and direct analysis of exopolysaccharides from biofilm on aluminum surfaces exposed to sea water using MALDI-TOF MS

Biofilm studies have extensive significance since their results can provide insights into the behavior of bacteria on material surfaces when exposed to natural water. This is the first attempt of using matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) for detecting the polysaccharides formed in a complex biofilm consisting of a mixed consortium of marine microbes. MALDI-MS has been applied to directly analyze exopolysaccharides (EPS) in the biofilm formed on aluminum surfaces exposed to seawater. The optimal conditions for MALDI-MS applied to EPS analysis of biofilm have been described. In addition, microbiologically influenced corrosion of aluminum exposed to sea water by a marine fungus was also observed and the fungus identity established using MALDI-MS analysis of EPS. Rapid, sensitive and direct MALDI-MS analysis on biofilm would dramatically speed up and provide new insights into biofilm studies due to its excellent advantages such as simplicity, high sensitivity, high selectivity and high speed. This study introduces a novel, fast, sensitive and selective platform for biofilm study from natural water without the need of tedious culturing steps or complicated sample pretreatment procedures.

Phosphate limitation to control biofouling

Phosphate limitation as a method to control biofouling of spiral wound reverse osmosis (RO) membranes was studied at a full-scale installation fed with extensively pretreated water. The RO installation is characterized by (i) a low feed channel pressure drop increase and (ii) low biomass concentrations in membrane elements at the installation feed side. This installation contrasted sharply with installations fed with less extensively pretreated feed water (and therefore higher phosphate concentrations) experiencing a high-pressure drop increase and high biomass concentrations in lead elements. Membrane fouling simulator (MFS) studies showed that low phosphate concentrations (approximately 0.3 microg P L(-1)) in the feed water restricted the pressure drop increase and biomass accumulation, even at high substrate (organic carbon) concentrations. In the MFS under ortho-phosphate limiting conditions, dosing phosphonate based antiscalants caused biofouling while no biofouling was observed when acids or phosphonate-free antiscalants were used. Antiscalant dosage could increase both phosphate and substrate concentrations of the water. Therefore, antiscalant selection may be critical for biofouling control. Since no biofouling was observed at low phosphate concentrations, restricting biomass growth by phosphate limitation may be a feasible approach to control biofouling, even in the presence of high organic carbon levels.

Reversal of Hepatic Fibrosis by Human CD34(+) Stem/Progenitor Cell Transplantation in Rats

Human umbilical cord blood (UCB) cells have many advantages as grafts for cell transplantation. Here, we transplant UCB cells into injured liver fibrosis, investigated the hepatic potential of UCB cells both in vitro and in vivo. a CCl4 rat model with liver fibrosis was prepared. Human (UCB) CD34(+) stem cell was separated with MACS (magnetic cell sorting). Cells were cultured with and without hepatic differentiation medium. Rats were divided into 3 groups; group (1): control healthy, group (2): CCl4 injected rats and group 3: CCl4/CD34(+)injected rats with human differentiated and undifferentiated cells through intrahepatic (IH) and intravenous (IV) routes. A significant elevation was detected in serum albumin in CCl4/CD34(+) compared to the CCl4 group (p<0.001). Serum ALT, had a significant decrease of its level after administration of stem cells compared to the CCl4 group (p<0.001). However, it was still significantly higher than control (p<0.001) with no significant difference between the groups that received stem cells. Histopathological examination of liver tissue showed that stem cells have a significant antifibrotic effect. Concerning gene expression, the collagen gene (rat) was highly expressed in the CCl4 group whereas its expression was significantly decreased after administration of stem cells. Human albumin and matrix metalloproteinase (MMP2) genes were expressed in liver tissues in the groups that received stem cells. Highest expression was in the group that received un-differentiated cells I.V. human UCB CD34(+) stem cells can ameliorate liver fibrosis in rats.

Two-step on-particle ionization/enrichment via a washing- and separation-free approach: multifunctional TiO2 nanoparticles as desalting, accelerating, and affinity probes for microwave-assisted tryptic digestion of phosphoproteins in ESI-MS and MALDI-MS: comparison with microscale TiO2

We introduce a simplified sample preparation method using bare TiO(2) nanoparticles (NPs) to serve as multifunctional nanoprobes (desalting, accelerating, and affinity probes) for effective enrichment of phosphopeptides from microwave-assisted tryptic digestion of phosphoproteins (alpha-casein, beta-casein and milk) in Electrospray Ionization Mass Spectrometry (ESI-MS) and Matrix Assisted Laser Desorption Ionization Mass Spectrometry (MALDI-MS). The results demonstrate that TiO(2) NPs can effectively enrich and accelerate the digestion reactions of phosphoproteins in aqueous solutions and also from complex real samples. After the microwave experiments, we directly injected the resulting solutions into the ESI-MS and MALDI-MS systems for analysis, and excellent sensitivity was achieved without the need for any washing procedure or separation process. The reasons are attributed to the high binding affinity and selectivity of TiO(2) NPs toward phosphopeptides. Thus, phosphopeptides can be adsorbed onto the TiO(2) NP surface. The digested or partially digested phosphoproteins can be concentrated onto the TiO(2) NP surface. This results in the effective or complete digestion of phosphoproteins in a short period of time (45 s). In addition, high sensitivity and sequence coverage of phosphopeptide can be obtained using TiO(2) NPs as microwave absorbers and affinity probes in MALDI-MS and ESI-MS. This is due to the photocatalytic nature of the TiO(2) NPs because the absorption of microwave radiation that can accelerate the activation of trypsin for efficient digestion of phosphoproteins and enhances the ionization of phosphopeptides. The lowest concentrations detected for ESI-MS and MALDI-MS were 0.1 microM and 10 fmol, respectively, for alpha-casein. Comparing the two-step approach of TiO(2) NPs with microscale TiO(2) particles, the microscale TiO(2) particles shows no effect on the microwave-assisted tryptic digestion of phosphoproteins. The current approach offers multiple advantages, such as great simplicity, high sensitivity and selectivity, straightforward and separation/washing-free technique for phosphopeptide enrichment analysis.