PSGR Krishnammal College for Women

Our previous study demonstrated that L-phenylalanine (L-Phe) can induce enhanced biocontrol efficacy of Yarrowia lipolytica against postharvest blue mold in pear fruit. This work also clarified the physiological mechanisms underlying the L-Phe-mediated improvement in biocontrol performance; however, the detailed molecular mechanisms responsible for this enhancement require further investigation. Results showed that Y. lipolytica cultured with 5 mmol/L L-Phe significantly reduced decay incidence in pear fruit without adversely affecting postharvest quality. In addition, L-Phe induction increased the production of volatile organic compounds by Y. lipolytica, effectively inhibiting the mycelial growth of Penicillium expansum. During storage, L-Phe treatment enhanced the oxidative stress tolerance of Y. lipolytica by alleviating ROS accumulation in yeast cells at fruit wound sites, which promoted better colonization of Y. lipolytica in wounds. Furthermore, L-Phe induction increased the activities of chitinase (CHI) and beta-1,3-glucanase (GLU) in Y. lipolytica, indicating enhanced cell wall metabolic activity. Transcriptome analysis revealed significant metabolic reprogramming in L-Phe-treated cells, with key pathways, including propanoate metabolism, glycerolipid metabolism, lysine degradation, butanoate metabolism, and tryptophan metabolism, being significantly upregulated. These changes improved both oxidative stress adaptation and energy utilization efficiency in the yeast. Overall, L-Phe induction effectively enhances the biocontrol capacity of Y. lipolytica, providing new insights into improving the performance of antagonistic microorganisms in postharvest disease control.

Pear fruit is susceptible to Penicillium expansum infection after harvest, leading to blue mold disease, which causes significant economic and safety concerns. This study evaluated the biocontrol potential of Hanseniaspora uvarum Y22, an antagonistic yeast isolated from organic farm soil, against blue mold in pear fruit via in vitro and in vivo experiments. The results showed a significant reduction in both blue mold incidence and lesion diameter following inoculation of 1 & times; 10 8 cells/mL H. uvarum Y22 in pear wounds. H. uvarum Y22 effectively prevented the germination of spores and the elongation of germ tubes in P. expansum. Further studies showed that H. uvarum Y22 could secrete extracellular beta-1,3-glucanase and chitinase, as well as adhered to and mycoparasitize pathogenic fungal hyphae. Its non-volatile organic compounds (NVOCs) exhibited no significant antifungal activity. Notably, volatile organic compounds (VOCs) generated by H. uvarum Y22 showed strong antifungal effects in vitro and in fruit fumigation experiments. The main VOC components identified by GC-MS were phenethyl acetate (45.90%), phenethyl alcohol (17.71%), and isopentyl acetate (14.60%), all of which displayed significant inhibitory efficacy against pathogen. These findings indicate that H. uvarum Y22 controls blue mold through preventing spore germination and the elongation of germ tubes, engaging in hyperparasitism, and emitting antifungal VOCs. This study establishes a theoretical foundation for developing of eco-friendly postharvest preservation methods for pear fruit, utilizing antagonistic yeast and its active volatile compounds.

This study presents a novel, first-of-its-kind synthesis and comprehensive characterization of cashew nutshell (CNS)-derived biochar for supercapacitor (SC) applications via a single-step, self-sustained gasification process, wherein no secondary or energy-intensive post-treatments-such as chemical activation, physical activation involving high-temperature steam or CO2, or hydrothermal activation-were employed. Instead, biochar generated as a by-product from conventional medium-to large-scale gasification was directly valorized using a canonical laboratory-scale batch-type reactor that closely replicates the operating principles and reaction environment of commercial downdraft gasifiers, ensuring both technological relevance and scalability. Two CNS biochar's synthesized under different air superficial velocities (5 cm/s and 20 cm/s) were systematically investigated. Structural and chemical characterization using X-ray diffraction and Raman spectroscopy confirmed the amorphous carbon framework, while synchrotron-based X-ray absorption spectroscopy revealed a lower unoccupied density of states in the C 2p pi* orbital and a higher degree of carbon disorder in CNS-5 compared to CNS-20. Electrochemical performance was rigorously evaluated through a comprehensive three-electrode configuration and validated using a two-electrode symmetric cell, providing a realistic assessment of device-level performance. The CNS-5 electrode exhibited a high specific capacitance of 186 F/g along with excellent electrochemical durability, retaining 137% of its capacitance after 10,000 charge-discharge cycles at 5 A/g. Furthermore, a symmetric supercapacitor assembled using CNS-5 with 6 M KOH electrolyte and operated within a 1 V potential window delivered a specific capacitance of 38 F/g, a maximum power density of 1503 W/kg, and an energy density of 5.4 Wh/kg. Overall, this work demonstrates a novel, scalable, and sustainable gasification-enabled route for producing functional biochar electrodes, paving the way for green and a self-sustaining circular energy-materials supply chain.

The search for renewable and sustainable energy sources is increasing worldwide, urges the identification of biofuels from insects. The possibility of producing biodiesel and biogas from insects has gained significant attention as a better alternative to conventional fossil fuels. This approach is due to the presence of high lipid and protein contents of certain insect species, including black soldier fly larvae, mealworms and crickets, which can be cultivated on organic waste streams. Insects such as black soldier flies and mealworms require minimal water and land for cultivation, and their waste-based diet reduces environmental impacts while promoting waste valorization compared to traditional biofuel feedstocks. Insects’ lipids can be extracted and converted into biodiesel through transesterification, while the remaining biomass, rich in proteins and other organic materials, can be anaerobically digested to produce biogas. This dual production pathway not only maximizes energy output but also generates valuable by-products, such as residual organic fertilizer. This review emphasizes the potential of insect-based biofuel conversion and its recent advances. The challenges in scaling up the process, and optimizing yields are critically evaluated. The environmental and technological parameters of the entire biofuel production process from insects are discussed in terms of their sustainability aspects.

In recent decades, plant-based metabolites have gained prominence in the pharmaceutical and food industries. In this present investigation, pisiferic acid (PA) an abietane diterpene acid with a chemical formula of C20H28O3, has been characterized using combined theoretical and experimental approaches to detail its spectroscopic, structural, topological, reactive site prediction, biological interactions, and solvent effects on its frontier molecular orbitals (FMO), electronic spectra, and molecular electrostatic potential (MEP) analysis. The optimized molecular structure comprises 53 bond distances and 101 bond angles. The vibrational wavenumbers revealed the characteristic peaks associated with hydroxyl, methine, carbonyl, methyl, and methylene groups. The HOMO-LUMO energy gap values are calculated at 5.3745 eV (Gas), 5.371 eV (Ethanol), 5.3699 eV (Water), 5.375 eV (Chloroform), and 5.3773 eV (Toluene). The electrophilic and nucleophilic reactive sites within the molecular structure were confirmed with the Mulliken charge distribution and molecular electrostatic potential (MEP) analysis. The topological finding reveals that the hydrogens H42 linked to carbon C18 in the meta position relative to the O3-H45 hydroxyl group and H27 in the CH2 methylene group were highlighted in red, indicating increased electron density or localized electron regions. In ADMET prediction, pisiferic acid exhibits drug-likeness characteristics. In addition, the molecular docking against antiapoptotic proteins Bcl-2 and Bcl-xL with a binding affinity of-6.77 and-6.68 Kcal/mol, supporting its antiapoptotic characteristics.