Rabia Naz

Antimicrobial potential of Ricinus communis leaf extracts in different solvents against pathogenic bacterial and fungal strains

OBJECTIVE To investigate the in vitro antimicrobial activities of the leaf extract in different solvents viz., methanol, ethanol and water extracts of the selected plant Ricinus communis. METHODS Agar well diffusion method and agar tube dilution method were carried out to perform the antibacterial and antifungal activity of methanol, ethanol and aqueous extracts. RESULTS Methanol leaf extracts were found to be more active against Gram positive bacteria (Bacillus subtilis: ATCC 6059 and Staphylococcus aureus: ATCC 6538) as well as Gram negative bacteria (Pseudomonas aeruginosa: ATCC 7221 and Klebsiella pneumoniae) than ethanol and aqueous leaf extracts. Antifungal activity of methanol and aqueous leaf extracts were also carried out against selected fungal strains as Aspergillus fumigatus and Aspergillus flavus. Methanolic as well as aqueous leaf extracts of Ricinus communis were effective in inhibiting the fungal growth. CONCLUSIONS The efficient antibacterial and antifungal activity of Ricinus communis from the present investigation revealed that the methanol leaf extracts of the selected plant have significant potential to inhibit the growth of pathogenic bacterial and fungal strains than ethanol and aqueous leaf extracts.

Phytochemical screening, antioxidants and antimicrobial potential of Lantana camara in different solvents

Objective To evaluate the antioxidant activity, hydrogen peroxide radicals scavenging activity, reducing power, the total phenolic and flavonoids contents, and antimicrobial and antifungal activities of methanol, ethanol and water extracts of leaves of Lantana camara (L. camara).

New supramolecular ferrocenyl phenylguanidines as potent antimicrobial and DNA-binding agents

Six new ferrocenyl phenylguanidines have been synthesized and characterized by elemental analysis, FT-IR, multinuclear (1H and 13C) NMR, and single crystal analysis. The latter showed a supramolecular structure for 2 mediated by O H and π H interactions. A subsequent DNA-binding study of these complexes proved them to be good DNA binders with the binding constant varying in the range of 1.2–5.6 × 105 M−1. These compounds were found to have moderate antibacterial and significant antifungal activities, especially for compounds having a chlorophenyl. These compounds may emerge as a new class of anticancer and antifungal agents alone or in combination with other drugs.

Protein Quantity and Quality of Safflower Seed Improved by NP Fertilizer and Rhizobacteria (Azospirillum and Azotobacter spp.)

HIGHLIGHTS Rhizobacteria (Azotobacter spp.) have improved the quality and quantity of safflower seed protein. Protein quality was confirmed by SDS-PAGE and new bands were found in response to different combinations of rhizobacteria and lower doses of fertilizers. The PGPR application has reduced the use of fertilizers upto 50%. Protein is an essential part of the human diet. The aim of this present study was to improve the protein quality of safflower seed by the application of plant growth promoting rhizobacteria (PGPR) in combination with conventional nitrogen and phosphate (NP) fertilizers. The seeds of two safflower cultivars Thori and Saif-32, were inoculated with Azospirillum and Azotobacter and grown under field conditions. Protein content and quality was assessed by crude protein, amino acid analysis, and SDS-PAGE. Seed crude protein and amino acids (methionine, phenylalanine, and glutamic acid) showed significant improvements (55–1250%) by Azotobacter supplemented with a quarter dose of fertilizers (BTQ) at P ≤ 0.05. Additional protein bands were induced in Thori and Saif-32 by BTQ and BTH (Azotobacter supplemented with a half dose of fertilizer) respectively. The Azospirillum in combination with half dose of fertilizer (SPH) and BTQ enhanced both indole acetic acid (IAA) (90%) and gibberellic acid (GA) (23–27%) content in safflower leaf. Taken together, these data suggest that Azospirillum and Azotobacter along with significantly reduced (up to 75%) use of NP fertilizers could improve the quality and quantity of safflower seed protein.

Pathogenesis-related protein expression in the apoplast of wheat leaves protected against leaf rust following application of plant extracts.

Leaf rust (Puccinia triticina) is a major disease of wheat. We tested aqueous leaf extracts of Jacaranda mimosifolia (Bignoniaceae), Thevetia peruviana (Apocynaceae), and Calotropis procera (Apocynaceae) for their ability to protect wheat from leaf rust. Extracts from all three species inhibited P. triticina urediniospore germination in vitro. Plants sprayed with extracts before inoculation developed significantly lower levels of disease incidence (number of plants infected) than unsprayed, inoculated controls. Sprays combining 0.6% leaf extracts and 2 mM salicylic acid with the fungicide Amistar Xtra at 0.05% (azoxystrobin at 10 μg/liter + cyproconazole at 4 μg/liter) reduced disease incidence significantly more effectively than sprays of fungicide at 0.1% alone. Extracts of J. mimosifolia were most active, either alone (1.2%) or in lower doses (0.6%) in combination with 0.05% Amistar Xtra. Leaf extracts combined with fungicide strongly stimulated defense-related gene expression and the subsequent accumulation of pathogenesis-related (PR) proteins in the apoplast of inoculated wheat leaves. The level of protection afforded was significantly correlated with the ability of extracts to increase PR protein expression. We conclude that pretreatment of wheat leaves with spray formulations containing previously untested plant leaf extracts enhances protection against leaf rust provided by fungicide sprays, offering an alternative disease management strategy.

Acute fasting-induced repression of the hypothalamic-pituitary-gonadal axis is reversed by RF-9 administration in the adult male macaque.

Recently, hypothalamic RFRP-3 (a mammalian ortholog of avian GnIH) signaling has been proposed as an important negative modulator of the reproductive axis. The current study examined whether repression of reproductive hormonal expression during short-term fasting conditions in higher-order primate is influenced by altered RFRP-3 signaling. Eight intact postpubertal male macaques (Macaca mulatta) were administered a single intravenous bolus of RF-9 (n = 4), a potent and putative RFRP-3 receptor antagonist, or vehicle (n = 4) following a 48-h fasting condition. Intermittent blood samples were collected every 30 min during the 4-h post-bolus period, and blood glucose, plasma cortisol, and testosterone concentrations were measured. Relative to fed conditions, fasting reduced glucose and testosterone levels (p < 0.005) and increased cortisol levels (p < 0.05). Relative to baseline, mean testosterone levels were elevated 150 min after RF-9 (p < 0.05) but not vehicle administration. In addition, elevated mean plasma testosterone levels following RF-9 administration were equivalent to levels observed in normal fed monkeys. These results suggest an important role for RFRP-3 signaling in conveying metabolic state information to the reproductive axis in higher primates.

Biologically Active New N, N', N''-Tri-Substituted Ferrocenyl Phenylguanidines and their Characterization.

BACKGROUND Introducing new candidates for various biological targets is a prime characteristic of the present day medicinal research and development. Guanidines are the important bioactive compounds and are well recognized for their diverse biological activities, especially as anticancer, antimicrobial and antioxidant agents. Due to the favorable electronic properties of ferrocene like lipophilicity, redox activity, stability in solution state and its easy derivatization, have made ferrocenyl compounds very popular molecules for biological uses. OBJECTIVES Keeping in sight, it is valuable to synthesize ferrocenyl guanidines to increase the binding potency with DNA, make them redox active and more lipophilic compounds. METHODS Six new ferrocenyl phenylguanidines (F1 - F6) have been synthesized via multi step protocol. The structures of F1 - F6 were established by using elemental analysis, UV-visible, multinuclear (1H and 13C) NMR and FTIR spectroscopy. Solution phase redox behavior, of the synthesized compounds, has been characterized by cyclic voltammetry. Two compounds (F2 & F4) were characterized by single crystal XRD. RESULTS Due to the biological importance of guanidines; these ferrocenyl guanidiens were screened for different biological activities like antibacterial, antifungal, antioxidant and DNA binding. DNA interaction study was done by using UV-visible spectrometry and cyclic voltammetry revealed good binding capacity of the test compounds. CONCLUSION The results revealed that the ferrocene incorporation to guanidines enhances their DNA binding ability. A similar trend was found in antioxidant and antimicrobial studies. Being the bioactive molecules these compounds are potential drug candidates.

Gonadotropin inhibitory hormone and RF9 stimulate hypothalamic-pituitary-adrenal axis in adult male rhesus monkeys

Stress activates gonadotropin inhibitory hormone (GnIH), hypothalamic-pituitary-adrenal axis (HPA-axis) and represses hypothalamic-pituitary-gonadal axis (HPG-axis) but RF9 administration relieves stress-induced repression of the HPG-axis. Importantly, it was not known whether GnIH signaling and RF9 synthetic peptide modulate the HPA axis. To assess this, mammalian orthologs of GnIH (RFRP-1 and RFRP-3) and RF9 were administered to intact adult male rhesus monkeys. RFRP-1 (125μg/animal), RFRP-3 (250μg/animal) and RF9 (0.1mg/kg BW) were intravenously (iv) injected into normal fed (n=4) monkeys. Additionally, a single bolus iv injection of RF9 (0.1mg/kg BW) was also administered to 48h fasted monkeys (n=4) to check the effects of RF9 signaling on an activated HPA-axis. Serial blood samples were collected, centrifuged and the obtained plasma was used for the analysis of cortisol by specific enzyme immunoassay. RFRP-1 treatment significantly increased cortisol levels while RFRP-3 increased the plasma cortisol, but the effect was non-significant. RF9 treatment significantly increased cortisol levels in normal fed animals. In contrast, RF9 injection did not significantly alter circulating cortisol in fasted monkeys. In conclusion, our results suggest stimulatory action of RFRPs and RF9 on the HPA axis in the adult male monkeys. However, the mechanism and site of action of RFRP-1 and RF9 along the HPA-axis is still unknown. Therefore, further studies are needed to decipher the mechanism and site of action of RFRPs and RF9 on the HPA axis in primates.

Pseudomonas putida improved soil enzyme activity and growth of kasumbha under low input of mineral fertilizers

ABSTRACT Effective management of the nutrients and enzyme activity in the soil is necessary for maximum crop growth and productivity. However, the excessive use of chemical fertilizers (CFs) not only adversely affects the soil nutrient status and soil physicochemical properties but also aids pollution to the ecosystem. The objective of present study was to investigate the effect of single as well as combined applications of phosphate-solubilizing bacteria and agrochemicals on important soil enzyme activities and their impact on the growth of kasumbha (safflower). Pseudomonas putida (P. putida;106 cells/mL) was applied as seed inoculation prior to sowing, and CFs were applied as full, half, and quarter doses during sowing to modulate the growth of kasumbha host plants. P. putida in combination with half dose of CFs (PH) increased the soil urease and phosphatase activities, while P. putida combined with quarter dose of CFs (PQ) augmented the soil invertase activities. Moreover, the PQ treatment exhibited the maximum colony-forming units of P. putida. Leaf chlorophyll, carotenoids, protein contents, and root lengths were increased by PH treatment. Whereas, shoot length and leaf area were improved by PH and PQ treatments, respectively. Leaf protease activity was enhanced by P. putida in combination with full dose of CFs and PQ treatments, while leaf phosphate contents were significantly improved by PQ treatment. It can be concluded that P. putida in combination with half as well as quarter doses of CFs is a promising approach for the improvement of soil enzyme activities and growth of kasumbha and replacing 50% of the use of CFs.

Botanical-chemical formulations enhanced yield and protection against Bipolaris sorokiniana in wheat by inducing the expression of pathogenesis-related proteins

Two experiments (pot and field experiments) were conducted in two consecutive years to evaluate the protective effects of botanical-chemical formulations on physiological, biochemical performance and grain yield of wheat inoculated with Bipolaris sorokiniana. We compared different formulations comprising Calotropis procera, Jacaranda mimosifolia, Thevetia peruviana extracts, chemical fungicide (mefenoxam) and salicylic acid to modulate the defense system of wheat host plants. Among the selected plant species J. mimosifolia aqueous and methanolic leaf extracts (1.2% w/v) resulted in 96 to 97% inhibition against B. sorokiniana. Both in pot and field experiments, among all the formulations of selected plant extracts the combined formulation of JAF2 (J. mimosifolia 0.6%)+MFF2 (mefenoxam 0.1%) lowered the dose of chemical fungicide required to reduce the leaf spot blotch disease. The same formulation induced resistance in wheat apparently through the accumulation of peroxidase, polyphenol oxidase, protease, acid invertase, chitinase and phenylalanine ammonia lyase. This formulation also stimulated the defense-related gene expression of PR-proteins. The same treatment gave even more increase (48%, 12% and 22%) in no. of grains/spike, grains weight and grain yield, than the MFF1 (mefenoxam 0.2%). We conclude that foliar application of J. mimosifolia leaf extract with very low dose of chemical fungicide (J. mimosifolia 0.6%+mefenoxam 0.1%) is a promising approach for the management of leaf blight and spot blotch in wheat.