Naegleria fowleri (N. fowleri) causes primary amoebic meningoencephalitis (PAM) which almost always results in death. N. fowleri is also known as "brain-eating amoeba" due to its literal infestation of the brain leading to an inflammatory response in the brain tissues. Currently, there is no single drug that is available to treat PAM, and most treatments are combinations of antifungal, anticancer, and anti-inflammatory drugs. Recently nanotechnology has gained attention in chemotherapeutic research converging on drug delivery, while oleic acid (OA) has shown positive effects on the human immune system and inflammatory processes. In continuation of our recent research in which we reported the effects of oleic acid conjugated with silver nanoparticles (OA-AgNPs) against free-living amoeba Acanthamoeba castellanii, in this report, we show their antiamoebic effects against N. fowleri. OA alone and its nanoconjugates were tested against the amoeba by using amoebicidal and host cell cytopathogenicity assays. Trypan blue exclusion assay was used to determine cell viability. The results revealed that OA-AgNPs exhibited significantly enhanced antiamoebic effects (P < 0.05) against N. fowleri as compared to OA alone. Evidently, lactate dehydrogenase release shows reduced N. fowleri-mediated host cell cytotoxicity. Based on our study, we anticipate that further studies on OA-AgNPs could potentially provide an alternative treatment of PAM.
Acanthamoeba castellanii belonging to the T4 genotype is an opportunistic pathogen which is associated with blinding eye keratitis and rare but fatal central nervous system infection. A. castellanii pose serious challenges in antimicrobial chemotherapy due to its ability to convert into resistant, hardy shell-protected cyst form that leads to infection recurrence. The fatty acid composition of A. castellanii trophozoites is known to be most abundant in oleic acid which chemically is an unsaturated cis-9-Octadecanoic acid and naturally found in animal and vegetable fats and oils. This study was designed to evaluate antiacanthamoebic effects of oleic acid against trophozoites, cysts as well as parasite-mediated host cell cytotoxicity. Moreover, oleic acid-conjugated silver nanoparticles (AgNPs) were also synthesized and tested against A. castellanii. Oleic acid-AgNPs were synthesized by chemical reduction method and characterized by ultraviolet-visible spectrophotometry, atomic force microscopy, dynamic light scattering analysis, and Fourier transform infrared spectroscopy. Viability, growth inhibition, encystation, and excystation assays were performed with 10 and 5 μM concentration of oleic acid alone and oleic acid-conjugated AgNPs. Bioassays revealed that oleic acid alone and oleic acid-conjugated AgNPs exhibited significant antiamoebic properties, whereas nanoparticle conjugation further enhanced the efficacy of oleic acid. Phenotype differentiation assays also showed significant inhibition of encystation and excystation at 5 μM. Furthermore, oleic acid and oleic acid-conjugated AgNPs also inhibited amoebae-mediated host cell cytotoxicity as determined by lactate dehydrogenase release. These findings for the first time suggest that oleic acid-conjugated AgNPs exhibit antiacanthamoebic activity that hold potential for therapeutic applications against A. castellanii.
Herbal medicines are becoming more popular and acceptable day by day due to their effectiveness, limited side effects, and cost-effectiveness. Cholistani plants are reported as a rich source of antibacterial, antifungal, antiprotozoal, antioxidant, and anticancer agents. The current study has evaluated antiviral potential of selected Cholistani plants. The whole plants were collected, ground and used in extract formation with n-hexane, ethyl acetate and n-butanol. All the extracts were concentrated by using a rotary evaporator and concentrate was finally dissolved in an appropriate vol of the same solvent. All of the extracts were tested for their antiviral potential by using 9-11 days old chick embryonated eggs. Each extract was tested against the Avian Influenza virus H9N2 strain (AIV), New Castle Disease virus Lasoota strain (NDV), Infectious bronchitis virus (IBV) and an Infectious bursal disease virus (IBDV). Hemagglutination test (HA) and Indirect Hemagglutination (IHA) tests were performed for different viruses. The overall order of the antiviral potential of Cholistani plants against viruses was NDV>IBV>IBDV>AIV. In terms of antiviral activity from extracts, the order of activity was n-butanol>ethyl acetate>n-hexane. The medicinal plants Achyranthes aspera, Neuroda procumbens, Panicum antidotale, Ochthochloa compressa and Suaeda fruticose were very effective against all four poultry viruses through their extracts. The low IC50 values of these extracts confirm the high antiviral potential against these viruses. It is worth to mention that Achyranthes aspera was found positive against IBDV through all its extracts which overcome the problem of unavailability of any known drug against IBDV. In short, the study proved that Cholistani plants are rich source of antiviral agent and their extracts can be used as good source of antiviral drugs both in crude and in purified form.
Phosphorous (P) plays the prominent role to promote the plants storage functions and structural roles, as it is recognized as a vital component of ADP, ATP, Cell wall as well as a part of DNA. Soils acts as the sink to supply P to plants because soil pH and its physical condition are the main factor which regulate the solubility and availability P element. Phosphorus is not deficient in Pakistani soils but its availability to plants is the serious matter of concern. A pot experiment was conducted to evaluate P dynamics in two different soil series of Pakistan (Bahawalpur and Lyallpur) using Maize as test crop. The treatments applied were T0: Control (without any fertilizer), T1: Recommended DAP @648 mg pot-1, T2: Half dose DAP @324 mg pot-1, T3: Recommended rate of TSP @900 mg pot-1, T4: Half dose TSP @450 mg pot-1. Soil analysis showed that Bahawalpur soil has sandy clay loam texture with 33% clay and Lyallpur series has sandy loam texture with 15.5% clay; furthermore, these soil contain 4.6 and 2.12% CaCO3 respectively. Results showed an increase in P concentration in roots (23 mg kg-1) with the application of half dose of TSP in Lyallpur series and lowest in Bahawalpur series (14.6 mg kg-1) at recommended dose of DAP. Concentration of P in shoots responded the same; increase at half dose of TSP (16.7 mg kg-1) and lowest at full dose of DAP in Bahawalpur series as (15.58 mg kg-1). Adsorbed P (17 mg kg-1) was recorded highest in Bahawalpur soil with more clay amount in pot with DAP application but lower in Lyallpur soil series (14 mg kg-1) with the application of applied TSP. The PUE was recorded highest in Lyallpur series with the application of half dose of TSP and it was 61% more than control and was Highest in Bahawalpur series was with the application of recommended dose of DAP is 72% more than control treatment. On estimation; results showed that applied sources made an increase in P availability than control, but TSP gave better P uptake than DAP unless of rates applied. Soil of Lyallpur series showed better uptake of P and response to applied fertilizers than Bahawalpur series which showed more adsorption of P by high clay and CaCO3 amount. Conclusively, the study suggested that soil series play a crucial role in choosing fertilizer source for field application.