Rhizobium pusense-Mediated Selenium Nanoparticles-Antibiotics Combinations against Acanthamoeba sp.

Severe ocular infections by Acanthamoeba sp. lead to keratitis, resulting in irreversible vision loss in immune-compromised individuals. When a protozoal infection spreads to neural tissues, it causes granulomatous encephalitis, which can be fatal. Treatment often takes longer due to the transition of amoeba from trophozoites to cyst stages, cyst being the dormant form of Acanthamoeba. A prolonged use of therapeutic agents, such as ciprofloxacin (Cipro), results in severe side effects; thus, it is critical to improve the therapeutic efficacy of these widely used antibiotics, possibly by limiting the drug-sensitive protozoal-phase transition to cyst formation. Owing to the biomedical potential of selenium nanoparticles (SeNPs), we evaluated the synergistic effects of ciprofloxacin and Rhizobium pusense-biogenic SeNPs combination. SeNPs synthesized using Rhizobium pusense isolated from root nodules were characterized using UV-Visible spectrophotometer, FT-IR, SEM with EDX, particle size analysis, and Zeta potential. The combination was observed to reduce the sub-lethal dose of Cipro, which may help reduce its side effects. The selenium and ciprofloxacin (SeNPs-Cipro) combination reduced the LC50 by 33.43%. The anti-protozoal efficacy of SeNPs-Cipro was found to transduce through decreased protozoal-cyst formations and the inhibition of the galactosidase and protease enzymes of trophozoites. Furthermore, high leakage of sugar, proteins, and amino acids during the SeNPs-Cipro treatment was one primary reason for killing the trophozoites. These experimental results may be helpful in the further pre-clinical evaluation of SeNPs-Cipro to combat protozoal infections. Future studies for combinations of SeNPs with other antibiotics need to be conducted to know the potential of SeNPs against antibiotic resistance in Acanthamoeba.

Moringa Tree, Gift of Nature: a Review on Nutritional and Industrial Potential.

Purpose of Review: Worldwide occurring Moringa plant is commonly famous as a fruit vegetable, known as drumstick or shevga all over India. The miraculous nutritional potential of the drumstick plant was already proved by worldwide research. But in the common population, it is unknown for the nutritional potential of its leaves. The majority of the population is known it only as a fruit vegetable. The Moringa leaves contain almost all essential nutrients, growth factors, vitamins, amino acids, proteins, minerals, and metals like potassium, iron, and zinc. Besides these, nowadays, plant leaves may be used to prepare various nutritional supplements and medicine. Recent Findings: Besides this, this review takes into account some joint efforts of NASI, Allahabad-funded project to use these Moringa leaves for different formulations and its popularization efforts for malnutrition eradication in tribal, i.e., development of recipes of Moringa leaves that will not only make easy preparations but also help to make habitual use of Moringa leaves today. Summary: This review describes the morphology, occurrence, and distribution of Moringa sp., chemical constitutions of Moringa leaves, its potential as anticancer, antidiabetes, and antimicrobial agent and as a nutritional supplement and the commercial future of various products.

Bacterial Pigment Prodigiosin Demonstrates a Unique Antiherpesvirus Activity That Is Mediated through Inhibition of Prosurvival Signal Transducers.

Herpes simplex virus (HSV) is among the most prevalent viral infections worldwide and remains incurable. While nucleoside analogs are used to relieve symptoms of infection, they suffer from having serious adverse effects and are unable to abolish the virus from the host. Here, we demonstrate a unique antiviral effect of prodigiosin (PG), a natural secondary metabolite produced by Serratia marcescens, on HSV infection. We show that PG naturally exerts antiviral activity against HSV-1 and HSV-2 infections. PG treatment resulted in robust inhibition of viral replication in vitro and ex vivo in cultured porcine corneas. Additionally, PG protected against HSV-1 infection and disease progression in a murine model of ocular infection. In our quest to determine the molecular mechanisms of its antiviral activity, we show that PG specifically inhibits NF-κB and Akt signaling pathways and promotes accelerated cell death in HSV-infected cells. Our findings reveal novel antiviral properties of PG, suggesting its high potential as an alternative treatment for herpetic diseases. They also provide new information on antiviral effects of HSV-bacterial metabolite interactions.IMPORTANCE In this article, we provide a new role for a commonly found bacterial pigment in controlling herpes simplex virus infection, for which diverse and multimodal antiviral agents are needed to prevent drug resistance. Serratia marcescens is a red pigment (prodigiosin)-producing Gram-negative bacillus that is naturally found in soil and water. It is associated with many kinds of human infections, including wound and eye infections, and meningitis. Taking cues from previous studies on prodigiosin, including possible proapoptotic anticancer properties, we investigated how it might affect HSV infection. Interestingly, we found that it is a potent virucidal compound that disrupts host signaling pathways needed for HSV growth and survival. The mode of antiviral action suggests potentially broad activity against enveloped viruses. Our results also indicate that interactions with commensal bacteria may inhibit HSV infection, underscoring the importance of studying these microbial metabolites and their implications for viral pathogenesis and treatment.

Bio-functionalized silver nanoparticles: a novel colorimetric probe for cysteine detection.

Chemical interactions between nanoparticles and biomolecules are vital for applying nanoparticles in medicine and life science. Development of sensitive, rapid, low-cost, and eco-friendly sensors for the detection of molecules acting as disease indicator is need of an hour. In the present investigation, a green trend for silver nanoparticle synthesis was followed using leaf extract of Calotropis procera. Silver nanoparticles exhibited surface plasmon absorption peak at 421 nm, spherical shape with average size of 10 nm, and zeta potential of -22.4 mV. The as-synthesized silver nanoparticles were used for selective and sensitive detection of cysteine. Cysteine induces aggregation in stable silver nanoparticles owing to selective and strong interaction of -SH group of cysteine with silver nanoparticle surface. Cysteine-induced silver nanoparticle aggregation can be observed visually by change in color of silver nanoparticles from yellow to pink. Cysteine concentration was estimated colorimetrically by measuring absorption at surface plasmon wavelength. Limit of detection for cysteine using silver nanoparticles is ultralow, i.e., 100 nM. The mechanistic insight into cysteine detection by silver nanoparticles was investigated using FT-IR, TEM, DLS, and TLC analysis. Proposed method can be applied for the detection of cysteine in blood plasma and may give rise to a new insight into development of eco-friendly fabricated nanodiagnostic device in future.

Investigation of Bacterial Cellulose Biosynthesis Mechanism in Gluconoacetobacter hansenii.

The present study explores the mechanism of cellulose biosynthesis in Gluconoacetobacter hansenii. The cellulose synthase enzyme was purified as membrane fraction and solubilized by treatment with 0.1% digitonin. The enzyme was separated by native-gel electrophoresis and ß -D-glucan analysis was carried out using in vitro gel assay. The cellulose synthase has glycoprotein nature and composed two polypeptide subunits of 93 KDa and 85 KDa. The confirmation of ß -1,4-glucan (cellulose) was performed in whole and hydrolyzed monomeric sugar form. Tinopal and Congo red were used for cellulose detection on the gel. Thus the in vitro cellulose synthesis assay with cell free enzyme fraction was attempted to improve the understanding of cellulose biosynthesis.

Transformation of aromatic dyes using green synthesized silver nanoparticles.

Nowadays, increasing use of nanoproducts in area of human and environmental applications raises concern about safety aspects of nanoparticles synthesized using traditional physicochemical methods. Silver nanoparticles (AgNPs) synthesis at ambient parameters using latex of medicinally important plant Jatropha gossypifolia (J. gossypifolia) is reported in the present study. Potential of AgNPs in degradation of methylene blue and eosin B was also evaluated. Rapid formation of stable AgNPs was analyzed by visual color change from colorless to yellow-red after addition of latex in AgNO3 solution and by characteristic surface plasmon resonance (SPR) peak at 430 nm in UV-Vis spectroscopy. FT-IR analysis, protein coagulation test showed capping of proteins, flavonoids, terpenoids and polyphenols of latex on surface of AgNPs. FE-SEM, HR-TEM analysis revealed spherical shape of AgNPs. Narrow size range of AgNPs (5-40 nm) observed in HR-TEM analysis. EDS analysis confirms the presence of elemental silver while XRD revealed crystalline nature of AgNPs. Zeta potential of -21.4 mV indicates high stability of AgNPs. Effects of different parameters (pH, temperature, incubation time) on nanosynthesis were studied in the present study. Dye reduction studies were performed using UV-Vis spectroscopy, TLC, FT-IR and HPLC analysis showing decreased absorbance maxima of both dyes with respect to time, change in R f values, changes in wave number, transmittance, and retention time of dyes after AgNPs addition. The rate constant for methylene blue and eosin B reduction by AgNPs was found to be 0.062 and 0.022 min(-1).

Larvicidal activity of silver nanoparticles synthesized using Plumeria rubra plant latex against Aedes aegypti and Anopheles stephensi.

In the present study activity of silver nanoparticles (AgNPs) synthesized using Plumeria rubra plant latex against second and fourth larval instar of Aedes aegypti and Anopheles stephensi was determined. Range of concentrations of synthesized AgNps (10, 5, 2.5, 1.25, 0.625, 0.3125 ppm) and aqueous crude latex (1,000, 500, 250, 125, 62.50, 31.25 ppm) were tested against larvae of A. aegypti and A. Stephensi. The synthesized AgNps from P. rubra latex were highly toxic than crude latex extract in both mosquito species. The LC(50) values for second and fourth larval instars after 24 h of crude latex exposure were 1.49, 1.82 ppm against A. aegypti and 1.10, 1.74 ppm against A. stephensi respectively. These figures were 181.67, 287.49 ppm against A. aegypti and 143.69, 170.58 ppm against A. stephensi respectively for crude latex extract. The mortality rates were positively correlated with the concentration of AgNPs. The characterization studies of synthesized AgNPs by UV-Vis spectrophotometry, transmission electron microscopy (TEM), Particle size analysis (PSA) and zeta potential confirmed the spherical shape and size (32-200 nm) of silver nanoparticles along with stability. Toxicity studies carried out against non-target fish species Poecilia reticulata, the most common organism in the habitats of A. aegypti and A. stephensi showed no toxicity at LC(50) and LC(90) doses of the AgNPs. This is the first report on mosquito larvicidal activity of latex synthesized nanoparticles.