BackgroundBiogenic fabrication of silver nanoparticles from naturally occurring biomaterials provides an alternative, eco-friendly and cost-effective means of obtaining nanoparticles. It is a favourite pursuit of all scientists and has gained popularity because it prevents the environment from pollution. Our main objective to take up this project is to fabricate silver nanoparticles from lichen, Usnea longissima and explore their properties. In the present study, we report a benign method of biosynthesis of silver nanoparticles from aqueous-ethanolic extract of Usnea longissima and their characterization by ultraviolet–visible (UV-vis), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses. Silver nanoparticles thus obtained were tested for antimicrobial activity against gram positive bacteria and gram negative bacteria.ResultsFormation of silver nanoparticles was confirmed by the appearance of an absorption band at 400 nm in the UV-vis spectrum of the colloidal solution containing both the nanoparticles and U. longissima extract. Poly(ethylene glycol) coated silver nanoparticles showed additional absorption peaks at 424 and 450 nm. FTIR spectrum showed the involvement of amines, usnic acids, phenols, aldehydes and ketones in the reduction of silver ions to silver nanoparticles. Morphological studies showed three types of nanoparticles with an abundance of spherical shaped silver nanoparticles of 9.40–11.23 nm. Their average hydrodynamic diameter is 437.1 nm. Results of in vitro antibacterial activity of silver nanoparticles against Staphylococcus aureus, Streptococcus mutans, Streptococcus pyrogenes, Streptococcus viridans, Corynebacterium xerosis, Corynebacterium diphtheriae (gram positive bacteria) and Escherichia coli, Klebsiella pneuomoniae and Pseudomonas aeruginosa (gram negative bacteria) showed that it was effective against tested bacterial strains. However, S. mutans, C. diphtheriae and P. aeruginosa were resistant to silver nanoparticles.ConclusionLichens are rarely exploited for the fabrication of silver nanoparticles. In the present work the lichen acts as reducing as well as capping agent. They can therefore, be used to synthesize metal nanoparticles and their size may be controlled by monitoring the concentration of extract and metal ions. Since they are antibacterial they may be used for the treatment of bacterial infections in man and animal. They can also be used in purification of water, in soaps and medicine. Their sustained release may be achieved by coating them with a suitable polymer. Silver nanoparticles fabricated from edible U. longissima are free from toxic chemicals and therefore they can be safely used in medicine and medical devices. These silver nanoparticles were stable for weeks therefore they can be stored for longer duration of time without decomposition.

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Background Biogenic fabrication of nanoparticles from naturally occurring biomaterials involves plants, herbs, bacteria and fungi using water as neutral solvent, while chemical synthesis involves hazardous chemicals and leaves unwanted byproduct which unnecessarily pollute the environment. In order to prevent atmospheric pollution a safe, clean and green strategy for the synthesis of cupric oxide nanoparticles from aqueous leaf extract of Diospyros montana has been employed. D. montana of Ebenaceae family is a poisonous tropical plant which grows wild in Asia. Its extract is commonly known as fish poison. The rate of formation of NPs from plant extract is thought to be facile and rapid relative to those formed by fungi and bacteria, but it depends on the concentration of reducing chemicals available in the extract. We report, in this communication, a benign method of biogenic synthesis of cupric oxide nanoparticles (CuO-NPs) from leaf extract of D. montana and their characterization by UV–visible, FTIR, SEM, TEM, DLS, SAED and EDX analyses. Their antimicrobial activity against seven Gram-positive and four Gram-negative bacteria has been screened. Photocatalytic degradation of methylene blue by ascorbic acid as reducing agent and cupric oxide nanoparticles as catalyst has been done under sunlight. Results Cupric oxide nanoparticles of varying size starting from 5.9 to 21.8 nm have been fabricated from aqueous leaf extract of D. montana at room temperature. The pure extract absorbs at 273 nm while CuO-NPs exhibit a broad peak at 320 nm. FTIR spectrum of the leaf extract shows the presence of a double quinonoid molecule. There are three types of CuO-NPs with different hydrodynamic radii. Their average hydrodynamic radii fall between 495 ± 346 nm. SEM and TEM images show spherical shaped CuO-NPs of different size. SAED suggests crystalline nature of CuO-NPs. They are highly polydispersed in solution. EDX analysis reveals the presence of Ca, C, O, Na and Si besides copper. Oxygen content is over 50% by mass. Reduction of methylene blue dye (MB) by ascorbic acid as reducing agent, in presence of CuO-NPs as catalyst, has been achieved in 90 s at room temperature while their reduction by ascorbic acid alone takes more than 10 min. Antibacterial activity of CuO-NPs against seven Gram-positive (Staphylococcus aureus, Streptococcus mutans, Streptococcus pyogenes, Streptococcus viridans, Staphylococcus epidermidis, Corynebacterium xerosis and Bacillus cereus) and four Gram-negative bacterial strains (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Proteus vulgaris) has been investigated. The results indicated that NPs are highly effective against growth inhibition of Gram-positive bacteria than Gram-negative bacteria. Copper oxide nanoparticles are even more toxic than the standard antibiotic, norfloxacin. Conclusion In this project cupric oxide NPs of 5.9–21.8 nm have been fabricated from aqueous leaf extract of D. montana. It is most inexpensive and easy process to fabricate NPs from plant material because no toxic chemicals are used. Since CuO-NPs are toxic to several Gram-positive and Gram-negative bacterial strains, attempt may be made to use them as antibacterial agent to protect food, vegetable and crops. Also, the reduction of methylene blue dye by ascorbic acid as reducing agent in presence of CuO NPs as catalyst has been done very efficiently at a rapid rate which prompts us to use them as catalyst in the reduction of dyes, other toxic materials and industrial effluents. Further investigation of other beneficial properties of CuO-NPs can also be explored.

Gout is a potentially progressive and debilitating form of chronic inflammatory arthritis caused by the deposition of monosodium urate crystals in synovial fluid and other tissues, characterized by sudden & severe episode of pain, warmth and swelling in a joint. People suffering from recurrent attacks frequently experience pain and disability, reduced health-related quality of life and productivity and increased morbidity. NSAIDs, colchicines, glucocorticoids, uric acid lowering agent like uricostatic drugs (allopurinol, a xanthine oxidase inhibitor), Uricosuric drugs (Probenecid) are very effective but risky in patients having pre-existing renal, cardiovascular, gastrointestinal and metabolic disorders. Cupping (Al-Hijama) is a widely used therapeutic regimen of Unani system of medicine with high acceptance in Egypt and Arab countries. It is used for the treatment of various inflammatory and painful conditions like sciatica, gout, rheumatoid arthritis, pain of knee, removal of deep swelling, disease of liver and skin etc. It is a minor surgical excretory procedure related scientifically to the principles of renal glomerular filtration and abscess evacuation where a pressure-dependent excretion of causative pathological substances occurs. Cupping is thought to act mainly by increasing local blood circulation and relieving the painful muscle tension. It acts by improving microcirculation, promoting capillary endothelial cell repair, accelerating granulation, and angiogenesis in the regional tissues. It is the best deep tissue massage which normalizes the patient's functional state and progressive muscle relaxation. In Unani system of Medicine, this is a simple and economic treatment, effectively treating diseases with different etiologies and pathogenesis.

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