Mridul Umesh

The agricultural output has experienced a significant growth in the recent years to meet up the demands of the booming population. Agricultural growth is driven by factors such as expanded land use...

This research work focuses on the extraction and characterization of pectin from starfruit peel and its application for fabrication of pectin film. Starfruit is chosen as the source for pectin extraction as the data regarding pectin extraction starfruit is relatively scarce in the available literature. Conventional organic acid based extraction using citric acid is employed for pectin extraction as it is eco-friendly and cost effective. The yield of pectin was found to be 8.22 % ± 1.018 % (w/w). Fourier-transform infrared spectroscopy (FT-IR), analysis is used to identify functional groups present in the extracted pectin and X-ray Powder Diffraction (XRD) is done to check its crystallinity. Furthermore, scanning electron microscopy (SEM) characterization was performed to deduce the morphological characteristics of the extracted biopolymer. The particle size was found to be between 1 µm and 20 µm. Fabrication of pectin based film was done using solvent cast method. The biodegradable film developed was found to be transparent and flexible. This work highlights the use of starfruit as a cost effective substrate for pectin extraction. Future studies should aim at exploring various applications of pectin and utilizing its potential in diverse applications.

Abiotic stresses such as extreme temperatures and salinity are known to significantly influence the nutritional quality of vegetables during cultivation and postharvest handling. However comparative study on how different abiotic stresses alter ascorbic acid stability in root vegetables like red radish is understudied. Thus, the present study was conducted to evaluate the effect of various abiotic stresses (heat, cold and salinity) on ascorbic acid (AA) levels and antioxidant activity in red radish (Raphanus sativus L.). DCPIP titration and DNPH UV-Vis spectrophotometric techniques were used to analyse the ascorbic acid content, and the DPPH radical scavenging assay was used to measure antioxidant capacity. The findings showed that as stress duration and intensity increased, the total AA content decreased significantly (p < 0.05). At high temperature (90 °C), heat treatment resulted in a progressive decrease from 27.7 mg/100g to 20.8 mg/100g. Under cold stress, AA content increased slightly initially and then dropped by 22% on day 8. A two-phase response to salt stress was seen mild salt concentration leading to a moderately increased AA content, while severe salt concentration caused a 55% reduction after 72 hours. With an IC₅₀ value of 8.27mg/mL, the antioxidant activity increased as extract concentration increased from 3.8% to 62.1% inhibition. According to these findings, red radish exhibits a short-term adaptive defence in mild stress situations but a significant decrease in AA in severe stress situations. These findings are consistent with previous reports in other related vegetables such as tomato, broccoli and spinach, where moderate abiotic stress increases antioxidant defences before degradation occurs. These results suggest the need for efficient postharvest management and stress-aware storage techniques to preserve the functional and health-promoting qualities of red radish.

Nanomaterials have been an area of great research for the pollution control in recent decades due to their beneficial properties such as higher efficiency, low cost, easier fabrication, and higher surface area. Nanocarbons have been considered as a promising nanomaterial in remediation of emerging pollutants. Pharmaceutical compounds are one of the major products of healthcare which are present in different environments including water resources. These compounds include several categories of chemicals and medicines such as antibiotics, analgesics, antidepressants, hormones, and anticonvulsants. These pharmaceutical compounds enter the environment through sources such as pharmaceutical effluents, hospital waste, livestock farming, landfill leachate, and aquaculture industry. Considering the environmental and human health concerns associated with these pharmaceutical contaminants, the presented review is focused on understanding the mechanisms of pharmaceuticals removal through carbon-based nanomaterials by the processes such as adsorption and catalysis. In addition, it explores the factors which affect the removal efficiency of the pharmaceuticals by nanocarbons. Moreover, recent advances and emerging technologies such as hybrid materials and composites, smart and responsive nanocarbon systems, membrane technologies and artificial intelligence for predictive performance have been discussed. The review article also provides the information on critical challenges and future perspectives in the research area.

A fungal strain with comparably high chitosan yield was isolated from the Shivaganga hills and identified as Aspergillus versicolor AD07 through molecular characterization. Later, the strain was cultivated on Sabouraud Dextrose Broth (SDB) and wild jackfruit-based media to evaluate its potential for chitosan production. Among the various media formulations, the highest chitosan yield (178.40 ± 1.76 mg/L) was obtained from the jackfruit extract medium with added peptone and dextrose. The extracted chitosan was characterized through FTIR, XRD (reported a crystallinity index of 55%), TGA/DTG, and DSC analysis, confirming the presence of key functional groups and high thermal resistance. The extracted chitosan was fabricated into a sheet incorporated with 1% lemongrass oil; the sheet exhibited strong antibacterial activity against Escherichia coli (30 mm) and Bacillus megaterium (48 mm). The biodegradation studies reported a weight loss of 38.93 ± 0.51% after 50 days of soil burial. Further, the chitosan film was tested as a packaging material for paneer, demonstrating better preservation by maintaining nutritional quality and reducing microbial load over a 14-day storage period. These findings highlight the potential of A. versicolor AD07-derived chitosan, cultivated on a waste substrate medium, as a sustainable biopolymer for food packaging applications.

Polyhydroxyalkanoates (PHA) production from diverse group of microorganisms has been a topic for extensive research for several decades. Despite this extensive research explorations, commercialization of PHA is still facing major hurdles, mainly due to the high cost involved in PHA production and recovery. This study was designed to determine a sustainable approach to produce PHA using an underutilized fruit extract. The major novelty of this research work is the use of starfruit (Averrhoa carambola L.), a tropical fruit, as a substrate for PHA production employing Bacillus licheniformis NJ04. Commercialization of PHA production can help to tackle global issues like raising microplastic pollution and biomagnification. The maximum PHA production reported in this work was 3.8 g/L under optimized conditions like temperature of 37 °C, pH 7 under shaking conditions (120 rpm) with 2% glycerol and starfruit extract as a carbon source after 72 h of incubation. The extracted PHA was further characterized through (FTIR) Fourier-transform infrared radiation, differential scanning calorimetry (DSC), Thermogravimetric analysis (TGA), X-Ray diffraction (XRD), and Proton Nuclear magnetic resonance (1H NMR). Thus, the present work highlights a novel strategy for using starfruit waste as a cost-effective substrate for PHA production.