The application of plant derived extracts is increasingly becoming effective, environmentally friendly, innovative alternative approaches used to manage and control postharvest senescence, preserving quality, and maintaining storage life of horticultural crops. Neem extract is characterized by antioxidative, antifungal, antibacterial properties and contains several bioactive compounds which help reduce postharvest senescence and prolong shelf life. Peach fruits are perishable with short shelf life attributable to elevated respiration and transpiration rate afterward postharvest. Thus, contemporary research aimed to examine the impact of neem leaf extract (NLE) application using different concentrations (control, 10%, 20%, and 30% NLE) on the antioxidant activity and physiochemical characteristics of peach fruit over nine-day period under room temperature storage. Results indicated that NLE (30%) significantly diminished weight loss, decay, and respiration rate whereas yielding higher firmness than control. Moreover, peach fruit treated with NLE showed higher titratable acidity compared to untreated fruits, but their ripening index and soluble solids content were lower than control fruits. Furthermore, NLE-treated peach fruits preserved a much greater total phenolic and ascorbic acid content associated with lower total, reducing and non-reducing sugar contents than the control fruits. Enzymatic antioxidant activity including superoxide dismutase, peroxidase, catalase and protein content were significantly higher in 30%-treated peach fruit NLE compared to control fruits. Practically, these verdicts suggested that postharvest application of NLE 30% might be a useful strategy for maintaining peach fruit quality and extending its storage life for up to nine days.

Abstract Food safety with maintained fruit quality is an important challenge for postharvest industry of citrus fruits. The present study was designed to check the effects of gamma irradiation on postharvest fruit quality of ‘Kinnow’ mandarin stored at 5 ± 1 °C and 90 ± 5% Relative Humidity. In the first experiment, fruits were exposed to different doses of gamma radiation (100-500 Gy), while after analyzing the results of first experiment, in the second experiment fruits were treated with 500, 600, 800 and 1000 Gy of gamma radiation. It was observed that higher doses of gamma irradiation exhibited lower weight loss and disease incidence as well as inhibiting the increase of soluble solid content (SSC) and retained higher titratable acidity (TA) and lower SSC: TA ratio. After 90 days of storage, maximum levels ascorbic acid, total phenolic contents and total antioxidants along with catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) activities were recorded higher in fruits treated with 800 Gy. These fruit also exhibited higher score of taste, aroma and texture during storage. Overall results suggest that pre-storage treatment of 800 Gy is the most effective treatment and have potential application for quality management of ‘Kinnow’ mandarin under long term cold storage.

Nanochemistry has emerged as a pioneering discipline that merges chemistry, physics, and materials science at the nanoscale, unlocking novel properties and phenomena. This comprehensive review article explores the significance of nanochemistry in modern times and its role in bridging the gap between the micro and nano worlds. The objective is to provide a comprehensive outlook on nanochemistry, covering fundamental concepts, synthesis approaches, nanomaterials, characterization techniques, applications, safety considerations, regulatory frameworks, and future directions. The article highlights the unique properties exhibited by materials at the nanoscale, such as quantum size effects and surface-to-volume ratio, and delves into different synthesis approaches and their advantages and limitations. Various nanomaterials, including quantum dots, nanowires, nanorods, nanotubes, and graphene, are explored, emphasizing their properties and potential applications. The review comprehensively elucidates nanochemical characterization techniques, ranging from electron microscopy to spectroscopy, showcasing their roles in analyzing and understanding nanomaterials. Furthermore, it discusses the wide-ranging applications of nanochemistry in medicine, electronics, energy, and the environment, with a focus on their transformative potential. Safety considerations and regulatory frameworks regarding nanotoxicology are addressed, emphasizing responsible development and usage of nanomaterials. The review concludes by summarizing key points and offering insights into future prospects, including emerging materials and potential breakthroughs. This comprehensive review article contributes to the advancement of nanochemistry and its potential impact on various industries.

Olives and its oil are considered an imperative element of diet due to their excellent nutritional quality. Geographical factors (i.e., geology, slope, elevation and temperature) and genetic variability in different olive cultivars influence plant growth, yield, oil and profiling of fatty acids. The prime objective of this investigation was to demonstrate the prodigious consequences of high temperature on the growth, production, and fatty acid composition of four olive cultivars (Coratina, Frantoio, Ottobratica and Leccino) at three different geographical locations (BARI, IOF, HRS) with the range of 460-751 m altitude during the year 2017 and 2018. The study has been carried out to investigate different parameters such as climatic conditions (rainfall and temperature), phenological attribute and yield traits (fruit set, fruit weight, yield, and oil content), and oil quality and profiling of fatty acids (free fatty acid contents, peroxide, palmitic acid, palmitoleic acid, oleic acid, linoleic acid, and linolenic acid). The results indicated a positive correlation of yield with rainfall and negative with the temperature was observed among olive cultivars. The results showed higher rainfall (1189 mm) and temperature (37.51 °C) at location-1 and lower rainfall (525 mm) and temperature (36.05 °C) at location-3. Coratina and Frantoio depicted significantly higher fruit set and yield in warmer climatic regions (Location-1 and Location-2) while Leccino and Ottobratica showed better results in the cooler region. Higher oil content was found in Frantoio and Coratina at location-3 among other locations and other cultivars. Overall, the lowest free fatty acid value was exhibited in Coratina and the highest in Ottobratica at all locations in both seasons. The contents of peroxide were observed higher in Leccino and lower in Coratina at all locations. The results revealed less variation among fatty acid composition in cultivars and seasons, however, palmitic acid, palmitoleic acid and oleic acid contents were found higher at location-2, linoleic acid at location-3, and linolenic acid at location-2 in all four olive cultivars. Custer analysis revealed two main groups and group-I contained two subgroups (A and B) while group-II contained three subgroups (C, D and E). In principal component analysis (PCA), PC1 axis had Leccino-L3, Leccino-L1, Frantoio-L1, Ottobratica-L1, Coratina-L1, and Leccino-L3 and explained 91.99% of the total variation. Therefore, geographic location influence growth, yield and olive oil quality attributes. Keywords: Climatic conditions; Acid value; High temperature; Free fatty acids;· Oleic acid;· Olive cultivars; Pothwar-Pakistan

Papaya fruit has a limited shelf life due to its sensitivity to decay and chilling damage during cold storage. The application of methyl jasmonate (MeJA) is known to reduce the incidence of disease and chilling injury, and to maintain the overall quality of the papaya fruit when stored at low temperature. Consequently, the effects of postharvest MeJA (1 mM) immersion on papaya fruits during low-temperature storage (10 °C ± 2 °C) for 28 days were studied. The experiment revealed that MeJA treatment significantly decreased the papaya fruit's weight loss, disease incidence, and chilling injury index. Furthermore, the accumulation of malondialdehyde and hydrogen peroxide was markedly lower after the application of MeJA. In addition, MeJA treatment exhibited significantly higher total phenols, ascorbic acid, antioxidant activity, and titratable acidity in contrast to the control. Similarly, MeJA-treated papaya fruits showed higher antioxidant enzymatic activity (superoxide dismutase, catalase, and peroxidase enzymes) with respect to the control fruits. In addition, MeJA reduced the soluble solids content, ripening index, pH, and sugar contents compared to the control fruits. Furthermore, MeJA-treated papaya fruit exhibited higher sensory and organoleptic quality attributes with respect to untreated papaya fruits. These findings suggested that postharvest MeJA application might be a useful approach for attenuating disease incidence and preventing chilling injury by enhancing antioxidant activities along with enhanced overall quality of papaya fruits during low-temperature storage.

Introduction Exogenous melatonin (EMT) application has been used to reduce postharvest senescence and improve the quality and antioxidant enzyme activities of papaya fruits during cold storage. Methods The effects of exogenous melatonin application (1. 5 mM) were investigated on papaya fruits during cold storage (10°C ± 2°C) for 28 days in the present study. Results and discussion The EMT treatment delayed postharvest senescence significantly with lower maturing status compared with untreated papaya fruits (control). In addition, EMT treatment maintained substantially higher titratable acidity values and ascorbic acid content but significantly lower soluble solids content and lower weight loss compared with the untreated fruits. Concerning the antioxidant capacity, the EMT-treated papaya fruit exhibited markedly higher total phenolic content and, consequently, higher DPPH-radical scavenging activity than the control group. The EMT treatment not only kept a higher enzyme activity of superoxide dismutase, peroxidase, and catalase but also significantly inhibited the accumulation of hydrogen peroxide and malondialdehyde, along with satisfying sensory attributes. Conclusion The findings of this study indicated that EMT application could be commercially used as an eco-friendly strategy to reduce postharvest senescence and maintain the fresh-like quality traits of papaya fruit during cold storage.