Soft rot is a severe postharvest disease of kiwifruit that causes enormous economic losses annually. In this study, we aimed to explore an effective pullulan-based active coating, incorporating food additives to reduce soft rot and extend the shelf life of cold-stored kiwifruit. The results showed that 1 g/L potassium metabisulfite could completely inhibit the mycelial growth of Diaporthe sp., Botryosphaeria dothidea, Phomopsis sp. and Alternaria sp., which were the primary pathogens of kiwifruit soft rot. Furthermore, the pullulan coating, combined with a 10 g/L potassium metabisulfite group, had a decay rate 46% lower than the control (CK) group and maintained fruit quality at the end of shelf life. The retention of physicochemical properties such as soluble solid content (SSC), firmness, weight loss and respiration rate also confirmed the efficacy of the treatment. In addition, at the end of shelf life, pullulan coating, combined with potassium metabisulfite, increased the accumulation of total phenolic content (37.59%) and flavonoid content (9.28%), maintained a high energy charge (51.36%), and enhanced superoxide dismutase (SOD) (6.27%), peroxidase (POD) (62.50%), catalase (CAT) (84.62%) and phenylalanine ammonia lyase (PAL) (24.61%) enzyme activities as well as initiating the upregulation of their gene expression levels. As a result, the disease resistance of fruit was improved, and the occurrence of soft rot was delayed. Overall, this study demonstrated that using the pullulan-based active coating incorporating potassium metabisulfite treatment effectively controlled soft rot and retarded the senescence of postharvest kiwifruit.

The acceptance of kiwifruit by consumers is significantly affected by its slow ripening and susceptibility to deterioration. Ready-to-eat “Guichang” kiwifruit and its preparation technology were studied by the regulation of ethylene and 1-MCP. Harvested kiwifruits were treated with 100–2000 μl L⁻¹ethylene for 36 h (20°C) and then treatment with 0–0.5 μl L⁻¹ 1-MCP. The results showed that the preservation effect of 0.5 μl L⁻¹ 1-MCP is inefficient when the soluble solid content of kiwifruit exceeded 15%. The ethylene-treated fruits reached an “edible window” after 24 h, but a higher concentration of ethylene would not further improve ripening efficiency, while the optimal ethylene concentration was 250 μl L⁻¹. Moreover, after 250 μl L⁻¹ ethylene treatment, 0.5 μl L⁻¹ 1-MCP would effectively prolong the “edible window” of fruits by approximately 19 days. The volatile component variety and ester content of 0.5 μl L⁻¹ 1-MCP-treated fruits were not different from those of the CK group. Principal component analysis and hierarchical cluster analysis indicated that the eating quality of fruits treated with 0.5 μl L⁻¹ 1-MCP was similar to that of fruits treated with ethylene. Consequently, ready-to-eat “Guichang” kiwifruit preparation includes ripening with 250 μl L⁻¹ (20°C, 36 h) ethylene without exceeding the 1-MCP threshold and then treated with 0.5 μl L⁻¹ 1-MCP (20°C, 24 h). This study highlights the first development of a facile and low-cost preparation technology for ready-to-eat “Guichang” kiwifruit, which could reduce the time for harvested kiwifruit to reach the “edible window” and prolong the “edible window” of edible kiwifruit.

To determine whether the bicarbonate in karst limestone soil could be used as a new carbon resource for biomass production by the catalysis of carbonic anhydrase (CA), a simulative karst drought stress experiment was designed and performed. Three plants used for biofuel energy, Orychophragmus violaceus L. (Ov), Brassica juncea L. (Bj), and Euphorbia lathyris L. (El), were grown under simulated karst drought stress. In response to drought stress, the photosynthesis of the three energy plants was inhibited, but their CA activity increased. The hypothesis was confirmed by plant physiological and stable isotope techniques. The obtained results showed that plant biomass was produced with atmospheric CO₂ as well as bicarbonate under drought stress. Bicarbonate use was proportional to the CA activity of the plants. With high CA activity over a long period, El had the highest proportional bicarbonate use compared to Ov and Bj, reaching 26.95%. Additionally, a new method is proposed for the screening of plants grown for energy in karst habitats.

Currently, pristine and functionalized metal-organic frameworks (MOFs) are introduced in heterogeneous catalysis for biomass upgrading owing to the specific texture properties including regular higher-order structure, high specific surface area, and the precisely tailored diversity. The purpose of this review is to afford a comprehensive discussion of the most applications in biomass refinery. We highlight recently developed four types of MOFs like pristine MOFs and their composites, MOF-supported metal NPs, acid-functionalized MOFs, and biofunctionalized MOFs for production of green, sustainable, and industrially acceptable biomass-derived platform molecules: (1) upgrading of saccharides, (2) upgrading of furan derivatives, and (3) upgrading of other biobased compounds.

To determine whether ozone can regulate fruit ripening and delay fruit aging, Kiwifruit (Actinidia deliciosa 'Guichang') was fumigated with different ozone concentrations (100 μL/L, 200 μL/L, 300 μL/L) for 3 h, stored at 1 °C and 85 ± 5% RH for three months, and then matured at 20 °C and 85% RH for 12 days. Compared with controls, the optimal concentration of ozone delayed kiwifruit ripening during cold storage by delaying the respiratory burst that precedes fruit decay. Consequently, fruit firmness, nutrient content, and enzyme activity remained stable; the expression of AdACS1 and AdACO1 as well as the activity of ACC synthetase (ACS) and ACC oxidase (ACO) was downregulated, whereby ACC and MACC were accumulated. In addition, ozone-treated fruit showed significantly reduced infection with grey mold. The effect of ozone on kiwifruit at 200 μL/L was the best suited for delaying fruit senescence, maintaining high quality during storage and fruit ripening compared with other fruits. Overall, our study indicated that ozone may play a major residual role in the physiological process of fruit ripening; furthermore, ozone can affect ethylene biosynthesis and fruit changes associated with endogenous ethylene production.

Chinese cherries, with their delightful blend of sourness and sweetness, are highly favored for their taste and nutritional benefits. However, they mature in conditions of high temperatures and rainfall, making them vulnerable to fungal infections which compromise their post-harvest quality. Our research aimed to study the effects of pre-harvest spraying with salicylic acid (SA) and sodium nitroprusside (SNP) on the pathogenic fungi in Manaohong cherries and their subsequent storage quality. We discovered that using SA and SNP at varying fruit development stages preserved fruit hardness, texture, appearance, and respiratory rate during storage, although it did not significantly alter the fruit’s dimensions. Furthermore, this pre-harvest treatment preserved levels of titratable acids, total phenols, and other antioxidants in the cherries, bolstered the activities of certain antioxidant enzymes (SOD, APX), and inhibited the activity of PPO and POD enzymes.Notably, the SA treatment alone demonstrated superior storage performance compared to combined treatments. Our research also identified Alternaria alternata and Colletotrichum godetiae as the primary pathogens in Manaohong cherries. In in vitro experiments, neither SA nor SNP inhibited these fungi’s growth. Consequently, we evaluated 12 pesticides and determined that 5% hexaconazole and 50% benomyl were most effective against these pathogens. Thus, to enhance the shelf life of Manaohong cherries and ensure their post-harvest quality, we recommend a pre-harvest spray of a SA, and combined with 5% hexaconazole and 50% benomyl. This approach not only promises enhanced cherry longevity but also lays a foundational strategy for the flourishing Manaohong Cherry industry.