Abdul-Rehman Phull - Academia.edu (original) (raw)

Papers by Abdul-Rehman Phull

A simple approach has been developed to prepare gallotannin (GT) mediated silver nanoparticles (A... more A simple approach has been developed to prepare gallotannin (GT) mediated silver nanoparticles (AgNPs) for detection of Hg 2+ ion in aqueous solution. The synthesized silver nanoparticles was characterized by different techniques such as UV-vis spectrophotometry, XRD, scanning electron microscopy, and EDX. Amongst the all metal ion tested, only Hg 2+ shows selective colorimetric and fluorimetric change to GT capped AgNPs. A quick naked eye color change of GT capped AgNPs from yellowish-brown to colorless shows high sensitivity of present method. With addition of Hg 2+ ion, the fluorescence enhancement was observed for GT capped AgNPs. The mechanism for the change in color and fluorescence enhancement of nanoparticles with addition of incremental amount of Hg 2+ is due to the change in polarization near metal surface region and internal charge transfer phenomenon. The linear range for the detection of Hg 2+ was found to be 0.1-1 nM with lower detection limit (LOD) 0.037 nM. The present approach has been successfully utilized to quantitative determination of Hg 2+ from environmental samples. The another advantages of prepared silver nanoparticles (GT-AgNPs) is that it shows significant photocatalytic activity for organic transformation and anticancer potential against cancer cell line MDA-MB-231 and A375 with an LD 50 of 111.5 µg/mL and 185 µg/mL, respectively.

New derivatives of tetrakis(4-carboxyphenyl) porphyrin were designed, synthesized and characteriz... more New derivatives of tetrakis(4-carboxyphenyl) porphyrin were designed, synthesized and characterized by IR, proton NMR and
mass spectroscopy. The ground and excited state nature of new derivatives were examined using UV-Vis. absorption and
fluorescence spectroscopy, fluorescence quantum yield and fluorescence lifetime studies. The singlet oxygen quantum yield of
each synthesized derivative of porphyrin was estimated for their further efficacy as potential photosensitizer in biological studies.
The significant photophysical data of all synthesized derivatives was supplementary accessed to examine the cell imaging and
cytotoxicity against two cancer cell lines viz. MBA-MD-231 and A375. The fluorescence lifetime, fluorescence quantum yield
and efficiency of singlet oxygen generation suggests alkyl amine and alkyl hydrazide linked new porphyrin photosensitizers can
be useful for PDT agent in cancer treatment.

There are numerous extra- and intra-cellular processes involved in the production of reactive oxy... more There are numerous extra- and intra-cellular processes involved in the production of reactive oxygen species
(ROS). Augmented ROS generation can cause the damage of biomolecules such as proteins, nucleic acid and
lipids. ROS act as an intracellular signaling component and is associated with various inﬂammatory responses,
chronic arthropathies, including rheumatoid arthritis (RA). It is well documented that ROS can activate diﬀerent
signaling pathways having a vital importance in the patho-physiology of RA. Hence, understanding of the
molecular pathways and their interaction might be advantageous in the development of novel therapeutic approaches
for RA.

Melanin is the major factor that determines skin color and protects from ultraviolet radiation. I... more Melanin is the major factor that determines skin color and protects from ultraviolet radiation. In present study we evaluated the anti-melanogenesis effect of acetazolamide (ACZ) using four different approaches: enzyme kinetic, in vitro, in vivo and in silico. ACZ demonstrated significant inhibitory activity (IC 50 7.895 AE 0.24 lM) against tyrosinase as compared to the standard drug kojic acid (IC 50 16.84 AE 0.64 lM) and kinetic analyses showed that ACZ is a non-competitive inhibitor without cytotoxic effect. In in vitro experiments, A375 human melanoma cells were treated with 20 or 40 lM of ACZ with or without 50 lM of L-DOPA. Western blot results showed that ACZ significantly (P < 0.05) decreased the expression level of tyrosinase at 40 lM. Zebrafish embryos were treated with 10, 20 or 40 lM of ACZ and of positive control kojic acid. At 72 h of treatment with ACZ and kojic acid, ACZ significantly (P < 0.001) decreased the embryos pigmentation to 40.8% of untreated embryos at the dose of 40 lM of ACZ while kojic acid decreased only 25.0% of pigmentation at the same dose of kojic acid. In silico docking were performed against tyrosinase using PyRx tool. Docking studies suggested that His244, Asn260 and His85 are the major interacting residues in the binding site of the protein. In conclusion, our results suggest that ACZ is a good candidate for the inhibition of melanin and it could be used as a lead for developing the drugs for hyperpigmentary disorders and skin whitening.

Herbal nanoparticles gain lot of attention because of their pharmaceutical importance. The presen... more Herbal nanoparticles gain lot of attention because of their pharmaceutical importance. The present study reports the eco-friendly synthesis, characterization and their tyrosinase activity of silver nanoparticles (AgNPs) using aqueous extract of Bidens frondosa. The appearance of brown color indicated the formation of B. frondosa AgNPs. The Formation of AgNPs was confirmed by UV-Vis spectroscopy, FTIR, FESEM and EDS analysis. The formation of herbal AgNPs of size ranging 20-70 nm further was assured by energy dispersive X-ray spectroscopy (EDS) and field emission scanning electron microscopy (FESEM). The mushroom tyrosinase inhibitory activity of synthesized AgNPs was evaluated. Nanoparticles were found to have significant higher tyrosinase inhibitory activity compared to control. The IC 50 values of crude extract, AgNP and Kojic acid were found to be 9, 15, and 2.37 μg/mL, respectively. AgNPs of B. frondosa may be considered as potential candidate for the production of medical and cosmetic products.

Fucoidan is a sulfated polysaccharide widely distributed in brown seaweed. It exhibits several bi... more Fucoidan is a sulfated polysaccharide widely distributed in brown seaweed. It exhibits several bioactivities, such as anti-cancer, anti-tumor, anti-microbial, anti-diabetic and anti-oxidant properties. However, the effects of fucoidan in chondrocytes are not well established. Previously, we have reported in vitro and in vivo anti-inflammatory effects of fucoidan. In this study, we evaluated the effects and regulatory mechanism of fucoidan derived from Undaria pinnatifida on the cyclooxygenase-2 (COX-2) and type II collagen in rabbit articular chondrocytes. Using western blotting and alcian blue staining, respectively, fucoidan was shown to induce type II collagen and sulfated proteoglycan in a dose-and time-dependent manner. Moreover, fucoidan inhibited the COX-2 expression in a dose-and time-dependent manner and increased the phosphorylation of extracellular signal-regulated kinase (ERK), p38, and AKT kinases in chondrocytes. The inhibition of p38 and AKT using SB203580 and LY294002, respectively, in the presence of fucoidan decreased the expression of type II collagen. However, ERK inhibition using PD98050 stimulated type II collagen expression. Fucoidan increased COX-2 expression in the presence of inhibitors of ERK, p38, and AKT kinases. These results conclusively suggested that fucoidan regulated type II collagen expression via the p38 and AKT pathways, and COX-2 expression via the p38, ERK and AKT pathways in rabbit articular chondrocytes. Moreover, given its ability to mediate cell differentiation and exert anti-inflammatory activity, fucoidan may represent a potential therapeutic substance for use in inflammatory conditions, including arthritis.

Traditional approaches have been reported since a long time for curing and treatment of various a... more Traditional approaches have been reported since a long time for curing and treatment of various ailments. Sulphated polysaccharides from brown seaweeds such as fucoidan have been reported to possess significant antiinflammatory, antioxidant, antimicrobial, antiviral and antitumor activities. Herein, the antileishmanial, antimicrobial and anticancer activity of fucoidan from Undaria pinnatifida were investigated. The antileishmanial activity was evaluated by MTT assay. The antimicrobial activities were determined by using the agar disc diffusion method. While anticancer activity was determined by using the SRB colorimetric method. Results showed that fucoidan effectively inhibited the growth of Leishmania tropica promastigotes showing mortality rates ranging from 4.2-73.5% with LD50 value of 31.72 µg/ml. The antibacterial and antifungal activities of fucoidanat the concentration of 30µg/disc were tested against gram-positive bacteria (Micrococcus luteus and Staphylococcus aureus),gram-negative bacteria (Salmonella typhimurium)and fungal strains (Aspergillus flavus, Aspergillus fumigatus, Mucor species). Zones of inhibition obtained were compared with that of different standards cefixime for antibacterial activity and clotrimazole for antifungal activity. The results showed the maximum zone of inhibition of the bacterial growth against S. aureus (15.67±0.76 mm)and fungal growth against A. fumigatus (11.83±1.01) among test organisms. Fucoidan has shown considerable anticancer potential against human liver cancer (HepG2) cells (LD50, 18.01±1.2 μg/ml). Based on these results, it can be concluded that fucoidan as natural products, may serve as leads for the development of new pharmaceuticals having diverse therapeutic potential.

Fucoidan is a bio-functional polysaccharide, mainly reported in brown seaweed. Diverse potential ... more Fucoidan is a bio-functional polysaccharide, mainly reported in brown seaweed. Diverse potential of fucoidan has created intense interest to review the existing scientific literature, specifically focusing on prevention, associated molecular mechanisms in inflammation related ailments. Fucoidan inhibited inflammatory responses, both in vitro and in vivo experimental models. Inflammation is a complex response of living systems and involved in pathogenesis of different diseases, including arthritis, cancer and allergies. Sulfated glycans play a crucial role in inflammation related events such as they partake in the regulation of chemokines, rolling of leukocytes along the endothelium at inflammatory sites, and provide the structural assembly of subendothelial basement membrane. These functions make fucoidan as suitable exogenous sulfated polysaccharide to ameliorate the inflammatory events like regulating pro-inflammatory targets. Henceforth present study was carried out to provide the critical approach towards the anti-inflammatory properties and underlying molecular mechanisms on the basis of existing knowledge.

Oleanolic acid (OA) is a bioactive triterpenoid in medicinal plants. It possesses various pharmac... more Oleanolic acid (OA) is a bioactive triterpenoid in medicinal plants. It possesses various pharmacological properties, including analgesic, anti-inflam-matory, and antitumor effects. The effects of OA in chondrocytes, however, are not well characterized. Here, we used rabbit articular chondrocytes as a cellular model to investigate the effects and regulatory mechanisms of OA on dedifferentiation and pro-inflammation. OA promoted dedifferentiation of chondrocytes by inhibiting type II collagen and pro-inflammatory activity by increasing cyclooxygenase-2 (COX-2) expression. Furthermore increased phosphorylation of p38 kinases and down-regulated phosphorylation of ERK was observed. Inhibition of p38 with SB203580 in OA-treated cells rescued the expression of type II collagen and suppressed the expression of COX-2. However, ERK inhibition with PD98059 accelerated the OA-induced inflammatory responses. These results suggest that OA induces loss of type II collagen expression via the p38 pathway and induces inflammation through the p38 and ERK pathways in rabbit articular chondrocytes.

Chemistry & biodiversity, Jan 29, 2017

International journal of biological macromolecules, Jan 16, 2017

Seaweed and their constituents have been traditionally employed for the management of various hum... more Seaweed and their constituents have been traditionally employed for the management of various human pathologic conditions such as edema, urinary disorders and inflammatory anomalies. The current study was performed to investigate the antioxidant and anti-arthritic effects of fucoidan from Undaria pinnatifida. A noteworthy in vitro antioxidant potential at 500μg/ml in 2, 2-diphenyl-1-picrylhydrazyl scavenging assay (80% inhibition), nitrogen oxide inhibition assay (71.83%), hydroxyl scavenging assay (71.92%), iron chelating assay (73.55%) and a substantial ascorbic acid equivalent reducing power (399.35μg/mg ascorbic acid equivalent) and total antioxidant capacity (402.29μg/mg AAE) suggested fucoidan a good antioxidant agent. Down regulation of COX-2 expression in rabbit articular chondrocytes in a dose (0-100μg) and time (0-48h) dependent manner, unveiled its in vitro anti-inflammatory significance. In vivo carrageenan induced inflammatory rat model demonstrated a 68.19% inhibition ...

Pharmaceutical biology, 2017

Ostericum koreanum (Maxim.) Kitagawa (Apiaceae) roots are traditionally used as an analgesic and ... more Ostericum koreanum (Maxim.) Kitagawa (Apiaceae) roots are traditionally used as an analgesic and antiulcer agent. However, the antiulcer potential of isoimperatorin isolated from O. koreanum has not yet been explored. To evaluate the antiulcer activity of isoimperatorin isolated from the roots of O. koreanum. Isoimperatorin was isolated as cubic crystals by repeated column chromatography of the ethyl acetate fraction and structure was verified with (1)H NMR, (13)C NMR and high-resolution mass spectrometry (HRMS-FAB). The crystals obtained were analyzed with the single crystal X-ray method. The MTT assay was used to determine its cytotoxicity against chondrocytes at different concentrations (0.0-737.74 μM, 24 h). The in vivo antiulcer activity of isoimperatorin (40 mg/kg) was determined against ethanol-, indomethacin- and pyloric ligation-induced ulcers in Sprague-Dawley rats. Furthermore, the effect of isoimperatorin (0.0-737.74 μM, 24 h) on the expression of type II collagen in cho...

Pakistan Journal of Nutrition, 2016

Foodborne illness is a serious threat to public health around the world. Foodborne illness is cau... more Foodborne illness is a serious threat to public health around the world. Foodborne illness is caused by the consumption of harmful bacteria in form of contaminated food. The contamination of food occurred throughout the food chain from farm to industry and from market to kitchen. During the last few decades, the number of outbreaks caused by foodborne pathogens has dramatically increased. Consumers are now demanding fresh and safe food products. Food industry has shown deep concern about the safety of foods and in response adopted a number of decontamination techniques to ensure safe food supply. Among 31 foodborne pathogens, the most common pathogens found in the foods are Staphylococcus aureus and Listeria monocytogenes. These pathogens have been contributing significantly to the foodborne outbreaks and deaths toll around the world. Control of these pathogens became a great challenge for the food industry. This review focuses on various decontamination technologies used in the food industry to ensure food safety and to prevent these pathogens in the food products.

Future Journal of Pharmaceutical Sciences, 2016

Background: The methods like bio-green are advantageous over chemical and physical methods due to... more Background: The methods like bio-green are advantageous over chemical and physical methods due to ecofriendly and cost-effective synthesis of nanoparticles. Current study was designed for green synthesis of silver nanoparticles (AgNPs) and their biological evaluation. Methods: Methanolic extract of Bergenia ciliata (BC) rhizomes prepared by maceration was used for the synthesis of AgNPs and confirmed by UVevisible and Fourier Transform Infra-Red (FTIR) spectroscopy. Further field emission scanning electron microscope (SEM) was used for the shape and size determination. In vitro Antioxidant, antimicrobial and cytotoxic potential was determined by using standard protocols. Results: The nanoparticles were spherical in shape having average particle size of 35 nm. FTIR analysis revealed the possible involvement of phyto-constituents in silver nanoparticles of crude extract. Green synthesized nanoparticles (BCAgNPs) showed the enhanced antioxidant properties compared to the crude extract. These nanoparticles showed the cytotoxic effects against brine shrimp (Artemia salina) nauplii with a value of 33.92 mg/ml LD50. BCAgNPs were found effective against the pathogenic fungal and bacterial strains in comparison to the Bergenia ciliata extract. Conclusion: Green synthesized BCAgNPs showed enhanced biological activities. Present results also support the advantages of using bio-green method for the production of nanoparticles having the potential of antimicrobial and cytotoxic activities.

Environmental Nanotechnology, Monitoring & Management, 2015

River Chenab is one of the major sources of water for irrigation of agriculture fields in Punjab,... more River Chenab is one of the major sources of water for irrigation of agriculture fields in Punjab, Pakistan. The present investigation was conducted to appraise the effect of river Chenab sediments on growth; morphological and biochemical prospects of in vitro grown Brassica napus seedling. A total 19 residue samples collected from different sites of River Chenab were evaluated. The sediments extracts, in most of the cases, significantly influenced on final germination, rate of germination and mean period of final germination of B. napus seedlings in comparison with controls. Reduction in root length was observed as compared with shoot length. Decrease in relative dry weight of seedlings ranging from 45% to 64% was also examined. Biochemical analysis revealed that the sediments extracts tend to increase in total protein and total phenolic contents in B. napus plants while variation in MDA and flavonoid contents were observed as compared with control. Increase in chlorophyll a & b and carotenoid contents were also observed in plants germinated in the presence of sediments extracts except sample 4. The enzymes (POD, SOD and protease); responsible to mitigate hazardous effects of sediment contamination; were found elevated in the seedlings. Phytotoxic evaluations of sediments demonstrate that it is consistent and practical tool for assessing quality of sediment. However, increased activities of antioxidants; enzymes and proteins favor the adaptation or tolerance to contamination by the seedlings.

Chondrocytes are the exclusive cells residing in cartilage and maintain the functionality of cart... more Chondrocytes are the exclusive cells residing in cartilage and maintain the functionality of cartilage tissue. Series of biocomponents such as different growth factors, cytokines, and transcriptional factors regulate the mesenchymal stem cells (MSCs) differentiation to chondrocytes. The number of chondrocytes and dedifferentiation are the key limitations in subsequent clinical application of the chondrocytes. Different culture methods are being developed to overcome such issues. Using tissue engineering and cell based approaches, chondrocytes offer prominent therapeutic option specifically in orthopedics for cartilage repair and to treat ailments such as tracheal defects, facial reconstruction, and urinary incontinence. Matrix-assisted autologous chondrocyte transplantation/implantation is an improved version of traditional autologous chondrocyte transplantation (ACT) method. An increasing number of studies show the clinical significance of this technique for the chondral lesions treatment. Literature survey was carried out to address clinical and functional findings by using various ACT procedures. The current study was conducted to study the pharmacological significance and biomedical application of chondrocytes. Furthermore, it is inferred from the present study that long term follow-up studies are required to evaluate the potential of these methods and specific positive outcomes.

Chemistry & biodiversity, Jan 29, 2017

International journal of biological macromolecules, Jan 16, 2017

Pharmaceutical biology, 2017

Pakistan Journal of Nutrition, 2016

Future Journal of Pharmaceutical Sciences, 2016

Environmental Nanotechnology, Monitoring & Management, 2015