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Modified starch with resistant starch content and antioxidant activity from unripe Carica papaya fruits
No full text315-324Unripe Carica papaya fruits are often discarded during cultivation, contributing to environmental waste despite their
rich fibre and nutritional value. This study aimed to modify starch from unripe papayas by using different physical methods,
including steaming, drying, and microwaving. The starch samples were evaluated for their amylose content, resistant starch
levels, phenolic content, and antioxidant activity based on DPPH radical scavenging activity. Among the methods tested, the
combination of autoclaving and microwaving yielded the best results, with an amylose content of 2.760.02 mg/g, resistant
starch at 2.820.08%, polyphenols at 45.970.19 mg GAE/g, and an IC50 value for DPPH radical scavenging of
95.12 μg/mL, which showed slight antioxidant activity compared to the positive control (Trolox, IC50 10.07 μg/mL).
Furthermore, the modified starch samples were assessed for physical properties, including water solubility index
(31.160.63–44.040.80%), water absorption capacity (6.700.38–9.830.22 g/g), swelling power (20.270.42–27.600.29 g/g),
and light transmittance (37.590.21–49.320.25% on day 1). The findings provide valuable data on modified starch from
unripe Carica papaya fruits and offer a solution to reduce the annual disposal of unripe papayas, thereby mitigating their
environmental impact
Optimization of the extraction process of antioxidant compositions from Glycyrrhiza uralensis using the response surface method
No full text307-314This study aimed to optimise and evaluate the antioxidant activity of Glycyrrhiza uralensis root extract using a simple
heating method. The optimisation of extraction conditions was conducted using the Response Surface Methodology (RSM)
and a Box-Behnken design (BBD), focusing on variables such as temperature, ethanol concentration, extraction time, and
solvent-to-material ratio. The total phenolic content (TPC) and total flavonoid content (TFC) were used as response
variables. The optimal extraction conditions were determined to be a temperature of 58°C, ethanol concentration of 56%, a
liquid-to-solid ratio of 30 mL/g, and an extraction time of 190 minutes, resulting in TPC and TFC values of 158.81 mg
GAE/g and 122.15 mg QE/g, respectively. The extract exhibited considerable DPPH and hydroxyl radical scavenging
effects. These findings suggest that the optimized extraction method not only simplifies the process but also enhances the
scalability and cost-effectiveness of industrial applications
Phytochemicals identification, anti-microbial, anti-oxidant and anti-diabetic activities of Polygala sphenoptera Fresen
No full text246-257Polygala sphenoptera Fresen, belonging to the family Polygalaceae, is a plant traditionally used in folk medicine for various
health benefits. However, its chemical composition and pharmacological properties have not been explored. This study was to
prepare and optimise the ethanolic extract of P. sphenoptera, investigate its phytochemical composition, and evaluate its antimicrobial,
in-vitro anti-oxidant and anti-diabetic activities. The ethanolic extract of the authenticated whole plant of
P. sphenoptera was investigated for the presence of phytochemicals and evaluated for anti-microbial properties by determining
the minimum inhibitory concentration and zone of inhibition. The anti-oxidant capacity was evaluated using the 2,2-diphenyl-1-
picrylhydrazyl radical (DPPH) scavenging assay. The anti-diabetic potential was assessed by measuring α-amylase and
α-glucosidase inhibitory activities. Phytochemical investigations indicate the presence of carbohydrates, flavonoids, tannins,
alkaloids, and phenolic compounds. The phenolic content of the extract was found to be 8.733 mg GAE/g. The extract
demonstrated significant anti-microbial activity against both bacterial and fungal strains. In-vitro studies indicated that the plant
extract possesses strong anti-oxidant and anti-diabetic properties. Further detailed research will help to understand its
mechanisms and validate its therapeutic potential
Sequential Phase Feed Based Circularly Polarized RFID Reader Antenna for2.45 GHz Applications
No full text497-507A wideband, circularly polarized (CP) reader antenna is presented for 2.45 GHz RFID systems. To achieve circular
polarization, the antenna features a circular radiating patch on the top layer, fed by a sequential phase feed network located
on the bottom layer. An air gap is introduced between the two layers to minimize dielectric loss, thereby enhancing
directivity and radiation efficiency, which in turn increases overall gain. Cylindrical copper wires passing through the air
gap connect the bottom feed network to the top patch layer. By implementing incremental phase variations across the four
outputs of the feed network, the antenna achieves a −10 dB impedance bandwidth of 650 MHz (2.02–2.67 GHz) and a
circular polarization axial ratio (CP AR) bandwidth of 150 MHz (2.366–2.527 GHz). The antenna exhibits a peak gain of
8.4 dBiC and maintains a symmetric radiation pattern at 2.45 GHz. The physical dimensions of the antenna are 70 × 70 ×
13.2 mm³. The design provides a 3 dB axial ratio beamwidth of 91° and a half-power beamwidth of 63.9° in the X–Z plane
and 64° in the Y–Z plane. An equivalent circuit analysis is performed to better estimate the antenna's performance. The
design is experimentally verified and compared with simulation results. The proposed antenna is particularly suitable for
mobile RFID applications operating at 2.45 GHz, such as inventory management, asset tracking, access control, electronic
toll collection, and medication distribution
Thermal Impact of Chronic Exposure to High-Frequency Non-ionizing EM Radiation on Avian Skin: A Theoretical Approach
No full text536-543The manuscript reveals that the high-frequency electromagnetic radiations emitted from transmission towers affect birds'
health. As the number of mobile phones is increasing rapidly, this radiation is present almost everywhere in the environment.
This study uses a theoretical model based on Maxwell's equations to evaluate the thermal effects of electromagnetic radiation
(EMR) of 3.5 GHz to 5.5 GHz frequency on avian skin. When birds fly from 1 to 10 m around a mobile phone tower, the
electric field intensity is decreased by 90%. The results of the Specific Absorption Rate (SAR) inside the skin of avian show
that its value is directly proportional to the frequency of the incident electromagnetic wave. The change in temperature in the
skin tissue is calculated for the electromagnetic wave exposure duration of 1 to 15 min. At a frequency of 5.5 GHz and 1 m
from a transmission source, the SAR reached 27.65 W/kg, and the skin temperature increased by up to 7.11°C after 15 min of
exposure, indicating significant bioeffects. This study aids in the protection of birds by evaluating the thermal effects of
electromagnetic radiation exposure and contributes to establishing safer exposure limits
Antibacterial effect of silver and copper nanoparticles derived from Klebsiella pneumoniae-NSB2 strain against pathogenic bacteria
No full text482-490The rising threat of multidrug-resistant (MDR) bacteria has escalated the search for alternative antimicrobial solutions, including the use of nanoparticles. This study evaluated antibacterial activity of biosynthesized silver (AgNP) and copper nanoparticles (CuNP), produced by the Klebsiella pneumoniae NSB-2 strain against Escherichia coli and Staphylococcus aureus. UV-Visible spectrophotometry confirmed the synthesis of these nanoparticles, with absorption peaks at 421 nm for AgNPs and 419 nm for CuNPs. TEM analysis revealed spherical nanoparticles with sizes of 29.3 nm for AgNPs and 31.5 nm for CuNPs. AgNPs demonstrated a minimum inhibitory concentration (MIC) of 30 μg/mL for both pathogens, while CuNPs had an MIC of 40 μg/mL for E. coli and 30 μg/mL for S. aureus. Both nanoparticles exhibited bactericidal activity at 40 μg/mL, with AgNPs showing greater antibacterial potency. Growth rate (μ) and doubling time (Td) analyses revealed that bacterial growth slowed, and doubling times increased in the presence of both nanoparticles. Results indicate that AgNPs were more effective at lower concentrations compared to CuNPs, underscoring their stronger impact on bacterial growth kinetics. This study suggests that AgNPs and CuNPs hold promise as alternative treatments for MDR bacterial infections, with AgNPs showing superior efficacy
An overview of response pathways for protection of mitochondria from protein misfolding stress
No full text287-300Mitochondria are canonically known as cellular powerhouse but apart from ATP production, these organelles are hubs of
critical metabolic and cellular pathways like fatty acid metabolism, calcium signalling, heme biosynthesis, and apoptosis.
Mitochondrial proteome contains almost 1500 proteins to facilitate these cellular processes; however, maintaining a healthy
mitochondrial proteome is an extremely challenging task. As mitochondria are continuously exposed to various cellular
stresses, misfolding and aggregation of proteins is one of the most prominent outcomes of these stresses, protein misfolding
inside the mitochondria or on the mitochondrial surface poses a severe threat to mitochondrial health as well as to cellular
health. To cope with such proteotoxic stress, cells have evolved multiple stress response pathways, which help in the
maintenance of healthy mitochondrial proteome, resulting in prolonged cellular survival. Here in this review, we have
summarized the origin of mitochondrial proteotoxicity and cellular response to tackle these toxic proteins
Phytochemical investigation of Pelargonium graveolens and isolation of flavonol derivative
No full text106-108The compound 5-hydroxy-3,7-dimethoxy-2-(4-methoxyphenyl)-
4H-chromen-4-one (flavonol derivative) has been isolated from
Pelarogonium graveolens for the first time. The isolated bio-active
compound has been obtained from the chloroform extract of the
Pelarogonium. The compound has been analysed by spectral data and
its structure confirmed by X-ray crystallography analysis
Electrocatalytic activity of LaCoO3 on Ni-electrode for oxygen evolution reaction in 1M KOH at 25℃
No full text93-97The alginic acid sol-gel (AA) method has been used to synthesize perovskite-type oxide (LaCoO3) for the
electrocatalysis of water in alkaline solution. The extra pure nitrate salts of lanthanum, and cobalt and alginic acid have been
used in this process. The TGA, FT-IR, and XRD techniques established the formation of perovskite-type oxide. The
catalytic performance of fabricated oxide electrode towards the electrochemical formation of oxygen by the splitting of
water in an alkaline medium has been explored using the Tafel polarization and cyclic voltammetry techniques. Based on
the electrochemical investigation, fabricated LaCoO3/Ni electrode exhibits comparatively better electrocatalytic activity for
the oxygen evolution reaction (OER) in 1M KOH solution due to its higher value of oxide roughness factor (RF ≈ 16) and
with slightly lower Tafel slope (b ≈ 85 mV dec–1) than those prepared by the conventional routes. The OER follows a firstorder
reaction mechanism that occur by the adsorption of reaction intermediates