Sashidhar Rao Beedu

Size-controlled green synthesis of silver nanoparticles mediated by gum ghatti (Anogeissus latifolia) and its biological activity

Background Gum ghatti is a proteinaceous edible, exudate tree gum of India and is also used in traditional medicine. A facile and ecofriendly green method has been developed for the synthesis of silver nanoparticles from silver nitrate using gum ghatti (Anogeissus latifolia) as a reducing and stabilizing agent. The influence of concentration of gum and reaction time on the synthesis of nanoparticles was studied. UV–visible spectroscopy, transmission electron microscopy and X-ray diffraction analytical techniques were used to characterize the synthesized nanoparticles. Results By optimizing the reaction conditions, we could achieve nearly monodispersed and size controlled spherical nanoparticles of around 5.7 ± 0.2 nm. A possible mechanism involved in the reduction and stabilization of nanoparticles has been investigated using Fourier transform infrared spectroscopy and Raman spectroscopy. Conclusions The synthesized silver nanoparticles had significant antibacterial action on both the Gram classes of bacteria. As the silver nanoparticles are encapsulated with functional group rich gum, they can be easily integrated for various biological applications.

Spectroscopic and biochemical correlations during the course of human lens aging

BackgroundWith age, the human lens accumulates variety of substances that absorbs and fluorescence, which explains the color of yellow, brunescent and nigrescent cataract in terms of aging. The aim of this study was to assess lens fluorophores with properties comparable to those of advanced glycated end products (AGEs) in relation to age in human lenses. These fluorescent compounds are believed to be involved in the development of cataract.MethodsSpectroscopic (UV-Vis-NIR) and fluorescence photography (CCD-Digital based image analysis) studies were carried out in randomly selected intact human lenses (2–85 years). AGE-like fluorophores were also measured in water soluble and insoluble (alkali soluble) fractions of human lenses (20–80 years).ResultsOur experimental findings suggest that there was a progressive shift in the absorbance characteristic of intact lens in the range of λ210 nm-λ470 nm. A relative increase in the absorptivity at λ(511–520 nm), with age, was also observed. In addition, the ratio of absorptivity at λ(511–520 nm)versus the maximum absorbance recorded at blue-end cut-off (210–470 nm) was also found to increase, with age. The fluorescent intensity in the intact lens at both UV-B (λEx312 nm) and UV-A (λEx365 nm) were found to be positively correlated (r2 = 0.91 & 0.94, respectively; Confidence interval 95%) upto 50 years of age. In addition, a concomitant changes in AGE- like fluorophores were also observed in the processed lens samples (soluble and insoluble fractions) along the age. A significant increase in the concentration of AGE- like fluorophores, both in intact and processed lens was observed during the period of 40 – 50 years.ConclusionBased on the present investigation, it was concluded that significant changes do occur in the AGE-like fluorophores of human lenses during the period of 40–50 years.

Facile synthesis of palladium nanocatalyst using gum kondagogu ( Cochlospermum gossypium ): a natural biopolymer

Palladium nanoparticles (Pd NPs) were synthesised by using gum kondagogu (GK), a non-toxic ecofriendly biopolymer. GK acted as both reducing and stabilising agent for the synthesis of Pd NPs. Various reaction parameters, such as concentration of gum, Pd chloride and reaction pH were standardised for the stable synthesis of GK reduced stabilised Pd NPs (GK-Pd NPs). The nanoparticles have been characterised using ultraviolet-visible spectroscopy, transmission electron microscopy and X-ray diffraction. Physical characterisation revealed that the gum synthesised Pd NPs were in the size range of 6.5 ± 2.3 nm and crystallised in face centred cubic (FCC) symmetry. Fourier transform infrared spectroscopy implicated the role of carboxyl, amine and hydroxyl groups in the synthesis. The synthesised Pd NPs were found to be highly stable in nature. The synthesised nanoparticles were found to function as an effective green catalyst (k = 0.182 min⁻¹) in the reduction of 4-nitrophenol by sodium borohydride, which was evident from the colour change of bright yellow (nitrophenolate; λ(max) - 400 nm) to colourless (4-AP; λ(max) - 294 nm) solution. The overall objectives of the current communication were: (i) to synthesize the Pd NPs using a green reducing/capping agent; GK and (ii) to determine the catalytic performance of the synthesised Pd NPs.

Proximate, mineral composition and antioxidant activity of traditional small millets cultivated and consumed in Rayalaseema region of south India

BACKGROUND Millets are a diverse group of small seeded grasses, widely grown around the world as cereal foods. This communication details the proximate, mineral profile and antioxidant activity of six different small millets (Finger, Foxtail, Proso, Little, Barnyard and Kodo millets) and their 21 cultivars that are traditionally cultivated and consumed in the region of Ralayaseema, south India. RESULTS The proximate analysis revealed that these millets are rich in protein, fat, ash (mineral), total dietary fibre and total phenols with appreciable antioxidant activity. However, starch and amylose content was comparatively lower as compared to major millet sorghum. ICP-MS analysis of small millets demonstrated that they are rich in minerals such as Ca, P, K, Mg, Fe, Cu, Zn, Mn, Cr, Mo and Se. CONCLUSION Finger and kodo millets were found to be nutritionally superior over other small millets. The results suggest that small millets have a potential to provide food security and can combat micronutrient malnutrition.

Evaluation of Anti-inflammatory and Anti-nociceptive Potentials of Andrographolide and Forskolin: In vivo Studies

Abstract Andrographis paniculata and Coleus forskholii are medicinal plants, used in traditional Ayurveda systems and owe therapeutic properties due to their bioactive ingredients andrographolide and forskolin respectively. In the present investigation, both these molecules were evaluated at a dose of 10 mg kg−1 body mass administered by gavage, for their anti-inflammatory and anti-nociception (tail flick latency) properties in Wistar rats in comparison with the reference drug diclofenac. The studies were carried out independently. The percent inhibition in inflammation exhibited, by diclofenac were found to be 0, 18, 37, 20, and 17.2%, by andrographolide 0, 13.6, 29.6, 27.5, and 13.7% and by forskolin 0, 11, 40, 31, and 6.8% at 0, 30, 60, 90, 120 min drug reaction time respectively. Forskolin exhibited highest inhibitory effect (40%) at 60 min (p < 0.01). In the anti-nociceptive studies, diclofenac increased the tail flick latency time at 30, 60 and 90 min (p< 0.01), while andrographolide increased at 30 and 90 min (p < 0.01) and forskolin at 90 min (p < 0.05). The present studies establish that andrographolide and forskolin are potent anti-inflammatory as well as anti-nociceptive molecules.

Biogenic synthesis of biopolymer-based Ag–Au bimetallic nanoparticle constructs and their anti-proliferative assessment

This study reports an eco-friendly-based method for the preparation of biopolymer Ag-Au nanoparticles (NPs) by using gum kondagogu (GK; Cochlospermum gossypium), as both reducing and protecting agent. The formation of GK-(Ag-Au) NPs was confirmed by UV-absorption, fourier transformed infrared (FTIR), atomic force microscopy (AFM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The GK-(Ag-Au) NPs were of 1-12 nm in size. The anti-proliferative activity of nanoparticle constructs was assessed by MTT assay, confocal microscopy, flow cytometry and quantitative real-time polymerase chain reaction (PCR) techniques. Expression studies revealed up-regulation of p53, caspase-3, caspase-9, peroxisome proliferator-activated receptors (PPAR) PPARa and PPARb, genes and down-regulation of Bcl-2 and Bcl-x(K) genes, in B16F10 cells treated with GK-(Ag-Au) NPs confirming the anti-proliferative properties of the nanoparticles.