To achieve microbiological and physicochemical stability, drying is a widely employed food preservation technique. It operates on the principle of regulating water activity to a specified level. This method has a long history of prolonging freshness for food products (86). The current scalding method, which is carried out by the sample coming into direct contact with a medium like hot water or steam can significantly (p < 0.05) reduce the overall quantity of bacteria, increase drying effectiveness, and lessen the sample’s degree of browning during drying (87). But there have been reports of problems blanching with water and steam, which can result in nutrient loss such as protein, polysaccharides and vitamins (88). Crude protein content was lowered by 7.7% when using the solar drying method with a 5% infiltration concentration. However, crude fat, crude fiber, total ash, and carbs were all preserved at the same levels. Solar drying with a 5% infiltration decreased moisture by 7.7% while preserving the approximate composition of crude fat (2.3%), crude protein (25.1%), crude fiber (10.3%) total ash (10.2%), and carbs (44.4%). A microwave hot-air flow rolling dry-blanching method (MARDB) improves the drying effectiveness and quality of king oyster mushrooms. When drying and hot rinsing, microwaves can change the microstructure, which may impact drying properties, water status, and migration (89). The quality parameters, including color, water content, and polysaccharide content, were all greatly enhanced by MARDB. This also reduced drying time and totally inactivated PPO and POD. Excessive heat blanching decelerates the drying process while simultaneously reducing polysaccharides and phenolic compounds, resulting in decreased whiteness (90). Kurata et al. (91) used microwave vacuum dehydration (MVD) to dry shiitake mushrooms at varying microwave powers (25 W/g, 50 W/g, and 75 W/g of dry matter) and various absolute pressures (10 kPa,20 kPa,30 kPa,). Freeze drying (FD) achieves high-quality products by sublimating water directly from the solid to vapor phase, maintaining heat-sensitive properties like vitamins due to the low drying temperature (92). Freeze-dried products exhibit a porous structure due to ice crystal sublimation, but the process is hindered by high capital and energy costs from vacuum and refrigeration systems, resulting in limited throughput and slow drying (93). In summary, drying is a frequently employed food preservation method, which controls water activity to maintain microbiological and physicochemical stability (Table 3).

Mushrooms have been preserved by the sun for many years, which is one of the most popular methods for food preservation. Mushrooms are immediately sun-dried after harvest, continuing until they reach the desired moisture level of 10 to 13% (121). Sun drying, despite being weather-dependent and slower with inferior drying efficiency compared to high air velocity drying (HAD), was previously adequate for preserving mushrooms effectively. Sun drying may take as long as 3 days for each iteration to attain thorough desiccation, whereas hot air drying (HAD) only requires 12 h per cycle at a temperature of 60°C (97). Shiitake mushrooms that have been sun-dried exhibit higher concentrations of vitamin D2 than mushrooms dried using alternative methods, primarily due to the sun’s facilitation of ergosterol conversion into vitamin D₂ (122). The cumulative phenolic content in shiitake mushrooms dried in the sun exceeds that of mushrooms dried through the hot air drying (HAD) method according to Kim et al. (97). Shiitake mushrooms that were sun-dried indoors at 26°C for 36 h exhibited reduced levels of total phenolic content (93.4 to 3.9 mg/100 g in fresh shiitake), total antioxidants (109.5 to 5.4 mg/100 g in fresh shiitake), and scavenging activity (43.2 to 6.6%) in comparison to microwave and freeze-drying techniques (98). Conversely, hot air-drying employs controlled elevated temperatures typically ranging from 50°C to 80°C (122°F to 176°F), ensuring faster, consistent, and precisely regulated drying, making it ideal for large-scale commercial operations where temperature control is crucial for efficient drying (97) (Figure 4).

Mushroom shelf life must be extended by quickly removing heat after harvest and maintaining a low storage temperature. Low temperature is useful for minimizing moisture loss from mushrooms, decreasing microbe growth, and limiting their respiration rate (123). The browning was reduced by 75% by lowering the storage temperature from 25°C to 3°C (124). Research on Flammulina velutipes fruiting bodies examined the impact of refrigeration on nutritional content and active ingredients, revealing a significant decline in the natural antioxidant L-ergothioneine concentration after 8 days at 5°C in both bright and dark conditions, while total phenolic content increased notably over 10 days of refrigeration under fluorescent lighting; however, the antioxidant capacity decreased after storage in both dark and light conditions for five and 8 days (125). Vacuum cooling, despite its higher initial cost than conventional cooling systems, is the natural antioxidant L-ergothioneine concentration after 8 days at 5°C in both light and microbial growth (126). Mittal et al. (127) explored the impact of various pre-cooling methods and packaging materials (room cooling, hydrocooling, vacuum cooling, air forced cooling, polypropylene, polyvinylchloride and high impact polystyrene + polyvinylchloride) on the shelf life of Agaricus bisporus stored in specific environmental conditions (14 to 16°C and relative humidity 56 to 83%), revealing that vacuum cooling was the most effective pre-cooling method, followed by forced air cooling and room cooling, while punnet packages (HIPS, PP and PVC) were the preferred packaging materials, extending the shelf life and preserving the quality of mushrooms for up to 4 days. According to Tao et al. (128) vacuum cooling treatment and various storage conditions, including cold rooms and modified atmosphere packaging, affected antioxidant enzyme activity in Agaricus bisporus mushrooms, revealing that vacuum-cooled mushrooms exhibited enhanced activity of antioxidant enzymes like superoxide dismutase, catalase, peroxidase and polyphenoloxidase along with a reduction in malondialdehyde levels and the generation of superoxide anions. The most significant activation of the enzymatic antioxidant system was detected in mushrooms stored using modified atmosphere packaging combined with vacuum cooling treatment. In short, to extend the storage life of mushrooms, the use of lower storage temperatures can help minimize moisture loss and microbial growth. However, it may impact nutritional quality. Vacuum cooling, when paired with suitable packaging materials proves to be a successful approach for increasing shelf life. The combination of vacuum cooling and modified atmosphere packaging enhances antioxidant enzyme activity and lowers oxidative stress (128).

When mushrooms are stored for 28 days at 4°C post-harvest using active packaging infused with zeolite and acai extract they may experience alterations in their typical physical and chemical characteristics. Notably, mushrooms kept in these enhanced containers exhibited elevated levels of vitamin C and enhanced antioxidant potency, with a more pronounced effect observed in containers containing zeolite (129). For optimal color, maintain a moisture level between 87 and 90%. The most suitable humidity level for packaging mushrooms is 96% according to Wakchaure (130). Packaging techniques create a controlled environment for food products, preventing quality degradation and extending shelf life. Two primary methods include using plastic bags, allowing gas exchange through packaging films, and preserving items at a low temperature. This is done under consistent environmental conditions. Modified atmospheric packaging, characterized by higher CO₂ and lower O₂ levels compared to air, has been found to reduce respiration rates, ethylene production, sensitivity, microbial spoilage, and induce changes in physiological and biochemical processes.

However, without proper storage conditions, glycosaminoglycans and polysaccharides may diminish. An alternative approach known as Modified Active Packaging (MAP) has been devised to combat surface browning triggered by enzymatic reactions and anaerobic microbial attacks, by maintaining oxygen levels higher than carbon dioxide. According to Li et al. (131) Shiitake mushrooms were enclosed in three distinct packaging environments with varying oxygen levels: HOP (high oxygen packaging) with an initial oxygen concentration of 100%, MOP (medium oxygen packaging) with an initial oxygen level of 50%, and LOP (low oxygen packaging) with an initial oxygen content of 35% and an initial CO₂ content of 5%. During a seven-day storage period at 10°C and 90% relative humidity, an identical package filled with ordinary air served as the control. While all packages experienced a decrease in polysaccharides, color and integrity were preserved. Notably, LOP and AIR released more ethanol, while MOP and HOP released less. Additionally, the active packaging resulted in higher total amino acid and phenolic content than the control group. Wan-Mohtar et al. (103) explored the effectiveness of high CO₂ packaging (HCP) with a gas composition of 15% O₂ and 20% CO₂ in preserving king oyster mushrooms quality. In comparison to both the control group and low CO₂ packaging with 30% O₂ (HOP) and 2% CO₂ (LCP) it exhibited better outcomes. It displayed the highest cumulative phenolic content and demonstrated superior effectiveness in preserving color and aroma of P. eryngii.

The adoption of advanced post-harvest techniques, such as food irradiation, has the potential to enhance accessibility and prolong storage durations, and this technology has gained widespread acceptance. Extensive research has been conducted to assess the nutrient safety and technological benefits of irradiated food (132). This approach to mushroom preservation is safe and environmentally sustainable. Irradiation preserves the flavor, color, nutritional content and enhancing the flavor of mushrooms without leaving behind any detrimental residues. However, the influence of irradiation on mushrooms’ nutritional content can differ based on elements such as the specific mushroom variety the use of additional preservation techniques, radiation dosage, and the type of radiation source employed, which may include UV radiation, electron beams and gamma radiation (133).

UV radiation, in particular, enhances the vitamin D2 content in mushrooms, eliminates spoilage-causing microorganisms, and enhances the functional attributes of food. While doses of radiation 1–2 kGy can effectively eliminate insects, the eradication of bacteria may necessitate higher radiation doses of up to 10 kGy (134). WHO (world health organization) regards any food item exposed to radiation doses up to 10 kGy as safe and permissible (135). According to Fernandes et al. (133) gamma and electron beam irradiation have been found to delay or inhibit microbial growth, prevent stem elongation, reduce surface browning, and slow down mushroom maturation. This results in an extended shelf life for mushrooms, with the duration ranging from 10 to 15 days depending on the type of mushroom and the level of radiation exposure. Comparable results can be achieved through UV irradiation, with the added advantage of aiding the transformation of ergosterol found in shiitake mushrooms into Vitamin D2, thereby enhancing its nutritional value (136). Electromagnetic waves emanate from α and β rays originating from atomic nuclei. On an international scale, there are two officially sanctioned sources ¹³⁷Cs and ⁶⁰Co. Gamma radiation, by inhibiting cap expansion, stem elongation, discoloration, weight loss, and by enhancing the microbiological quality, prolongs the storage duration of mushrooms after harvest (137). Depending on the mushroom variety and the intensity of gamma radiation applied, irradiation produced varying impacts on the carbohydrates, protein, and micronutrients, including ash and tocopherols content in mushrooms (138). Electron beam irradiation, when compared to gamma radiation, offers a more convenient process with higher dosage rates and greater flexibility in starting and stopping. Exposure to radiation doses as high as 4 kGy showed enhancements the texture and color stability during preservation with sugars acting as the main source for mushroom respiration. Consequently, during preservation with high respiration rates often associated with increased degradation, a decrease in sugar levels is typically observed (139). Nevertheless, native dried mushrooms exposed to irradiation by electron beam demonstrated lower concentrations of acidic compounds when compared to their non-irradiated equivalents and electron beam irradiation resulted in an augmentation of the mushrooms’ antioxidant capability (140). In conclusion, active packaging, optimal moisture levels, and controlled atmosphere packaging methods enhance mushroom quality, while Modified Active Packaging and high CO₂ packaging combat browning and preserve quality. Food irradiation techniques, including UV radiation, electron beam irradiation, and gamma radiation, can modify mushroom characteristics, while ultrasound and pulsed light exposure have potential in preserving mushrooms. Table 3 provides a summary of the impact of UV, pulsed light, ultrasound, gamma irradiation and electron beam technologies on maintaining the freshness of fresh shiitake mushrooms.

Freshly harvested shiitake mushrooms often carry soil microorganisms and other impurities, which can be effectively removed through a water rinse. However, using water alone, while it may increase surface moisture, can potentially accelerate microbial growth and spoilage. To address this concern, antimicrobial agents like citric acid, sodium metabisulfite, sodium chloride or sodium hypochlorite are introduced into the water during washing. Furthermore, agents that inhibit browning may be employed to reduce surface browning. The introduction of chlorine dioxide became essential after it was determined that sulfur salts had adverse impacts on the overall quality of mushrooms by Singh and Sindhu (101); Ramteke et al. (141) conducted a study on shiitake mushrooms that had undergone chemical washing and drying. They examined the effects of hydrogen peroxide, citric acid, and sodium metabisulfite on post-harvest shiitake mushrooms. The findings indicated minimal sensory quality variations in terms of flavor, color, and overall sensory attributes between treated and untreated mushrooms. In a separate study, shiitake mushrooms were wrapped in PVC films, subjected to a wash with water containing 200 mg/L of chlorine. They were then stored at different temperatures (7°C, 10°C, and 15°C) for 15 days. Although initial washing reduced microbial counts, subsequent storage led to faster browning and bacterial growth than untreated mushrooms. However, mushrooms washed with a solution containing oxine (50 ppm), calcium chloride (0.5%), and sodium erythorbate (0.1%) exhibited a significant reduction in microbial load and delayed color deterioration, as observed in Wakchaure (130). According to Guan et al. (13) pre-treating mushrooms with 3% hydrogen peroxide (H₂O₂) water prior to UV-C light application resulted in a more substantial reduction in microbial count (0.85 log CFU/g) and an increase in total phenolic and ascorbic acid content during 14 days of storage, proving most effective in preventing lesions and browning in the mushrooms.

Fumigation is a common preservation technique used to retain agricultural products’ quality and increase shelf life. Essential oils are obtained from plants and are frequently used for fumigation because they perform a number of physiological processes, including antifungal, antibacterial, and antioxidant qualities. According to Jiang et al. (142) Freshly harvested shiitake mushrooms were fumigated with cinnamaldehyde, thyme, and clove essential oils at a concentration of 5 μL/L for 1.5 h at 10°C, followed by storage at 41°C and 90% relative humidity for 20 days. The evaluation of their antioxidant properties was carried out by measuring parameters such as H₂O₂ content, O₂ production rate and performing DPPH and ABTS radical scavenging assays. The results demonstrated a significant improvement in mushrooms’ antioxidant activities after exposure to cinnamonaldehyde. (DPPH 2, 2-diphenyl-1-picrylhydrazyl, is a stable free radical commonly employed to assess antioxidant capacity. Its reaction with antioxidants results in a color change, allowing quantification of antioxidant activity. ABTS 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) is utilized in antioxidant assays and like DPPH undergoes a color change upon interacting with antioxidants, aiding in antioxidant capacity assessment). This method preserved mushrooms’ natural antioxidant properties but also extended their shelf life by protecting them from microbial deterioration. Furthermore, this fumigation technique effectively prevented sensory quality degradation observed during shiitake mushroom storage. In a separate investigation shiitake mushroom subjected to a 5 μL/L cinnamaldehyde treatment and stored at 4°C for 15 days displayed no indications of deterioration or weight loss. Additionally, there was a substantial reduction in bacterial proliferation and phenolic compounds remained constant (143). According to Qian et al. (144) Subjecting mushrooms to cinnamaldehyde fumigation at a concentration of 40 nmol/L dissolved in 30% ethanol and subsequently storing them at 4°C for 30 days had no effect on the overall quantity of total phenolic compounds. However, it improved their stress resistance and bolstered their antioxidant potential.

Edible coatings have been extensively researched and created for mushroom post-harvest preservation. Coatings are a semipermeable barrier to CO₂, O₂, and moisture, changing the gaseous composition at the interface of the coating product. It can limit respiration, reduce moisture loss, delay ripening and maintain mushroom color and firmness. Chitosan, a naturally occurring biodegradable polymer, can serve as an edible covering to mitigate changes in mushrooms’ nutritional content while they are preserved (145). Liu et al. According to a study published in 2016, PA-g-CS (Protocatechuic acid grafted chitosan) combined with antioxidants showed promise for preserving king oyster mushrooms after harvest. The findings revealed that the PA-g-CS III coating, characterized by a high grafting rate, yielded the best outcomes by maintaining desirable textural attributes, minimizing membrane lipid peroxidation, elevating the activities of ascorbate peroxidase (APX), superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) while reducing the activities of polyphenol oxidase (PPO) (146). Shiitake mushrooms, when coated with a mixture of chitosan (1%) and guar gum (at concentrations of 5, 15, and 25%), and subsequently stored at 4°C with a relative humidity of 85 to 90% for 16 days, effectively preserved their firmness, prevented protein and ascorbic acid loss, increased the levels of soluble solids, sugars, and malondialdehyde, while preserving their flavor (104). The application of an Aloe vera coating enriched with basil oil at a concentration of 500 mL per liter to pristine mushrooms not only reduced the respiration rate but also maintained their firmness by preventing the differential leakage of electrolytes and the accumulation of malondialdehyde (147). Hence, the use of coatings and edible films enhances mushrooms’ antimicrobial properties and sensory attributes by mitigating respiration, weight loss, texture changes, and discoloration. In another study, shiitake mushrooms coated with a 1.5% w/v Nano-Ag film and stored at 4°C effectively reduced weight loss, prevented undesirable decay, surface discoloration, and other negative consequences throughout the 16-day storage period. Moreover, it effectively inhibited the proliferation of various microorganisms, including mesophilic, psychrophilic, yeast, molds, and others, thus preventing microbial spoilage (148).

Ozone is a strong antibacterial agent that is used to increase the extended durability of food owing to its elevated oxidizing potential causes it to quickly inactivate microorganisms by interacting with their cellular elements and intercellular enzymes. In a study conducted by Liu et al. (100) shiitake mushrooms were exposed to intermittent and single ozone treatments, then stored at a temperature of 4°C for a period of 14 days with 90% relative humidity demonstrating that periodic application at the ideal dosage of 3.2 mg/m³ outperformed the single treatment preserving proteins and phenolic compounds, inhibiting polyphenol oxidase activity to inhibit the occurrence of surface discoloration and decreasing the accumulation of unbound amino acids within the mushrooms. The study proposed that in order to substantially prolong the storage duration and boost the antioxidant capabilities of shiitake mushrooms, they should be subjected to ozone treatment for 30 min every 5 days applying a dosage of 3.2 mg per cubic meter (3.2 mg/m³). Yang et al. (149) observed similar results and found that utilizing ozone at a concentration of 4.28 mg/mᶾ, followed by preservation at 4°C for 25 days reduced nutrient loss and prevented surface expansion. The spoilage of mushrooms after harvest accelerates when no antimicrobial treatment is applied as the microbial load on the mushrooms increases during storage. Ozone, or triatomic oxygen, owing to its potent oxidizing properties exhibits robust antibacterial activity (150). According to Anjaly et al. (151) mushroom samples were exposed to ozone with different concentrations 10 and 15 ppm and durations 5 and 10 min. Subsequently, treated mushrooms were packaged in HDPE (high density polyethylene) material under both regular and vacuum atmospheric conditions and stored at 4°C with 90% relative humidity for a period of 15 days. Notably, the untreated mushrooms experienced a firmness increase from 3.5 to 14.1 g after 5 days of storage, while those treated with 10 ppm and 15 ppm of ozone exhibited the least firmness increase when stored in regular atmospheric conditions, as opposed to vacuum packaging. Zalewska et al. (152) explored mushroom samples were subjected to gaseous ozone treatment with different concentrations 0.05, 1.0, and 2.0 mg/L and exposure durations 30 and 60 min. The treated mushrooms packaged in PET (polyethylene terephthalate) boxes and wrapped with PVC (polyvinyl chloride) before being stored for 0 to 14 days at 2°C with 80% relative humidity. The firmness of untreated mushrooms increased from 15.3 to 19.6 N after 4 days and subsequently decreased to 10.95 N after 14 days. Mushrooms treated with 0.5 mg/L of ozone for 30 and 60 min showed firmness increases from 15.3 to 16.4 N and 18.1 N after 4 days, followed by declines to 5.9 N and 14.3 N after 14 days. In the case of ozone treatment at 1.0 mg/L for 30 min, the firmness increased from 15.3 to 17.7 N after 4 days and then decreased to 9.5 N after 14 days. However, after 60 min of ozone treatment, the firmness increased to 16.5 N from 9.6 N. With an ozone treatment of 2.0 mg/L for 30 and 60 min, the firmness increased from 15.3 to 17.5 N and 17.2 N after 14 days.

A burgeoning technology called cold plasma could supplant conventional storage techniques (153). When an electromagnetic field or electric field is applied to any gas, it undergoes ionization. This results in electrons colliding with the molecules or atoms within the gas and causing ionization. This, in turn, leads to the presence of chemically active entities like superoxide, free radicals, reactive oxygen species, and others within the plasma (154). These compounds inhibit various enzymes and bacteria while preserving the nutritional, physical, and sensory attributes of the materials intact (155). Xu et al. (156) examined the impact of plasma-activated water on postharvest quality of button mushrooms stored for 7 days at 20°C, revealing a reduction in bacterial and mold counts by 1.5 log and 0.5 log respectively, delayed firmness loss, and no significant alterations in color, pH, or antioxidant properties. Electrolyzed water generated through the electrolysis of a saline solution is a versatile disinfectant suitable for the food industry. Its effectiveness against microbes is determined by variables like the concentration of free available chlorine that forms hypochlorous acid (HClO) and its oxidation–reduction potential (ORP) by Rahman et al. (157). Aday (17) investigated the effect of electrolyzed water with different concentrations of 5, 25, 50 and 100 mg/L in combination with a passive modified atmosphere on button mushrooms. He revealed that those treated with 25 mg/L exhibited reduced browning, delayed weight loss and maintained texture. According to Castellanos-Reyes et al. (41), a low concentration of electrolyzed water with three other disinfectants aqueous ozone, 1% citric acid and sodium hypochlorite solution achieved reductions of 1.35, 1.08, and 1.90–2.16 log CFU/g in total aerobic bacteria, mold and foodborne pathogens respectively, following a 3-min treatment at room temperature (23 ± 2°C).

Demand for high-quality edible mushrooms is rising globally. There is a growing focus on environmentally and economically sustainable preservation methods. This is due to the promising potential of botanical extracts and essential oils to enhance edible mushrooms’ shelf life due to their diverse chemical components.

I. Lemon & oregano essential oils.

Lemon essential oil, derived from citrus lemons, enhances food preservation and flavor due to its potent antioxidant and antimicrobial properties, demonstrating notable antibacterial and antioxidant capabilities when integrated into chitosan/zeaxanthin composite membranes at different concentrations (158). As a consequence, Agaricus bisporus aging was delayed, and postharvest quality was maintained by suppressing microbial growth and respiration (110). Among the mushrooms wrapped in films infused with 6% lemon essential oil, the lowest browning and respiration rates were observed. Furthermore, these mushrooms effectively preserved their antioxidant attributes, improved tissue density, and prevented browning, while also demonstrating strong inhibitory effects against foodborne bacteria such as Staphylococcus aureus and Escherichia coli (110). The primary constituent carvacrol in oregano essential oil, is a potent bioactive substance renowned for its antioxidative and antimicrobial properties (159). At a concentration of 0.25 mg/mL, oregano essential oil completely inhibited S. aureus growth and exhibits antifungal properties against Candida albicans. Carvacrol distinguished by its phenolic hydroxyl group is thought to function as a peroxide radical generator in the oxidation process. This interrupts the lipid peroxidation cascade and safeguards against the oxidation of lipids. This research revealed that when stored and preserved, edible mushrooms exhibited better effectiveness in preventing microbial intrusion at higher concentrations of oregano oil (160).

II. Cumin & Cinnamon essential oils.

Cumin is a versatile spice extensively utilized in culinary preparations and is the world’s second-most frequently employed spice trailing only behind black pepper (161). Its potent antimicrobial characteristics are also used to safeguard edible mushrooms’ longevity (162). When preserving A. bisporus at 4°C with chitosan nanoparticles as a delivery system for cumin oil, microbial presence was reduced compared to conventional packaging. This method also played a role in maintaining antioxidant potential, enhancing tissue firmness and preventing the formation of brown spots in Table 3 (112). Cinnamon oil, an organic volatile oil recognized for its strong antimicrobial attributes, is a more common choice for preserving edible mushrooms (111, 163). When used in appropriate quantities cinnamon oil can fumigate mushrooms, delaying cap formation and preventing mushroom aging. Cinnamaldehyde’s remarkable antibacterial properties are attributed to its ability to alter the arrangement of lipids within the membranes of harmful microorganisms, ultimately causing membrane disruption (164). By inhibiting the growth of Salmonella typhimurium and hindering the production of the ATP synthase alpha chain protein involved in ATP synthesis. It also prevents the division of Bacillus cereus into newly formed cells (165). Through the reduction of the droplet size to ensure even distribution within the packaging, it significantly slows down the aging of A. bisporus. This is when subjected to refrigerated storage. This can be attributed to cinnamaldehyde’s antibacterial and anti-oxidative properties (166). According to Nair et al. (167) developed hybrid nanofibers by combining maize alcohol-soluble protein and ethyl cellulose in different ratios, incorporating CEO into electrospun fibers for A. bisporus. This approach successfully retained moisture and antioxidant capacity, boosted antioxidant enzyme activity, minimized browning enzyme activity, postponed aging and extended A. bisporus shelf life. Pan et al. (168) prepared cross-linked electrospun polyvinyl alcohol/CEO/βcyclodextrin (CPVA-CEO-β-CD) nanofiber films using electrostatic spinning incorporating CEO in PVA and β-CD-based fibers to achieve a controlled release of antibacterial agents. This method inhibited both Gram-positive and Gram-negative bacteria, prolonging the product’s shelf life.

III. Satureja khuzistanica & Turmeric essential oil.

Satureja khuzistanica possesses antiviral, antifungal, and antibacterial properties, along with vasodilatory, antidiarrheal, antispasmodic, hypolipidemic, and antioxidant qualities (169). According to Nasiri et al. (15) the impact of baicalin gum (TG) coatings with different concentrations (100, 500, and 1,000 ppm) of saturated SKO for preservation of A. bisporus mushrooms to maintain tissue firmness, sensory attributes, reduce microorganism growth, slow down the degradation of phenolic compounds and ascorbic acid, ultimately extending the shelf life of the mushrooms. The findings demonstrated that TG coating with saturated SKO (TGSKO) helped retain 92.4% of tissue firmness and decreased the presence of microorganisms like molds, and Pseudomonas. Furthermore, the mushrooms coated with TGSKO exhibited a 57.1% decrease in the browning index, notably higher total phenolic content (85.6%) and ascorbic acid accumulation (71.8%) (15). Turmeric derived from a plant with medicinal applications is the most widely favored spice in culinary applications and is a prominent ingredient in various health products (170). Its biological properties include anti-inflammatory, anticancer, antioxidant, and antibacterial properties (171). After 15 days of storage, it was observed that mushrooms treated with turmeric essential oil exhibited increased firmness fewer changes in a browning and microbial population and displayed the most minimal activity of PPO, ascorbic acid and total phenols concentration (172). In short, biopolymer-based edible films, shaped through blending and water evaporation, offer an eco-friendly packaging solution for the rising demand for high-quality edible mushrooms. These films, infused with botanical extracts and essential oils (e.g., lemon, oregano, cumin etc.) enhance shelf life, preserve antioxidants, and inhibit microbial growth in mushrooms.

Melatonin (MT) is a multifaceted compound commonly found in nature (173). Its diverse functions impact not only animals and humans but also influence plant growth and development (174). Melatonin biosynthesis is enzymatically transformed, non-enzymatically or pseudo-enzymatically into numerous active metabolites such as AFMK (N1-acetyl-N2-formyl-5-methoxykynuramine), 5-MT (5-methoxytrayptamine), C3HMO (cyclic 3-hydroxymelatonin) and AMK N1-acetyl-5-methokynuramine (175). Melatonin, derived from the amino acid tryptophan, plays a widespread role in nature. Tryptophan functions not just as a precursor to melatonin but also as a substrate for indole-3-acetic acid (IAA), potentially contributing to the diverse functions observed in the plant system. Figure 5A illustrates pathways to melatonin synthesis. Two major melatonin pathways exist based on enzymes. One is the tryptophan/tryptamine/serotonin/N-acetylserotonin/melatonin pathway, which may occur under normal growth conditions. The other is the tryptophan/tryptamine/serotonin/5-methoxytryptamine/melatonin pathway, which may be activated when plants produce substantial amounts of serotonin, such as during senescence (176, 177). Firstly, tryptophan is transformed into two different products: tryptamine through the action of the tryptophan decarboxylase (TDC) enzyme, and 5-hydroxytryptophan via the participation of tryptophan hydroxylase (TPH) enzymes. Serotonin is transformed into N-acetyl-serotonin by the enzyme serotonin-5-acetyl transferase (SNAT). Subsequently, N-acetyl serotonin is ultimately converted into melatonin by the enzyme known as N-acylserotonin methyltransferase (ASMT) Tryptamine and 5-hydroxytryptophan are metabolized into serotonin through the activity of tryptamine 5-hydroxylase (T5H) and tryptophane decarboxylase (TDC) enzymes, respectively (175, 178, 179).

Freshly harvested vegetables constitute living material and they undergo various physiological and biochemical processes, including respiration, hormonal fluctuations, dehydration, and enzymatic changes (180). The application of exogenous melatonin prompted the endogenous melatonin biosynthetic process through antagonistic interaction with calcium, thereby safeguarding the product against chilling injury and postharvest deterioration, as indicated in Figure 5B. At room temperature storage, melatonin treatment reduced the relative membrane-leakage rate and inhibited the generation of superoxide radicals (O₂), ethylene synthesis, hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), resulting in prolonged freshness and a reduction in browning and degradation of chlorophyll/pigments in fruits and vegetables (176). The application of melatonin resulted in a decrease in the relative membrane-leakage rate and the inhibition of superoxide radicals (O₂), malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) production. Simultaneously, it increased the activities of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR) and ascorbate peroxidase (APX). Conversely, it decreased the activities of browning-related enzymes, such as polyphenoloxidase (PPO) and peroxidase (POD). The intervention also increased the expression of four genes responsible for encoding enzymes involved in the repair of oxidized proteins: LcMsrA1, LcMsrA2, LcMsrB1, and LcMsB2 (181). Li et al. (114) investigated the impact of exogenous melatonin at different concentrations (0.1, 0.2, and 0.05, mM) on the texture, sensory attributes, and electron leakage in white mushrooms stored at 3 ± 1°C. The study revealed that mushrooms treated with 0.1 mM melatonin exhibited superior quality, accompanied by a significant reduction in electron leakage. Moreover, the results indicated that 0.1 mM melatonin preserved higher adenosine triphosphate levels and prevented the release of cytochrome c into the cytoplasm. Notably, this concentration notably suppressed electron leakage by enhancing the activities of complexes I and III through the upregulation of AbRIP1 and AbNdufB9 genes. Conversely, Gao et al. (115) concentrated on improving mushrooms’ tolerance to cadmium by examining antioxidant-related metabolites and enzymes to confirm the beneficial impact of melatonin on Cd-induced oxidative stress. Their findings suggest that MT enhances the antioxidant activity of Volvariella volvacea through processes such as amino acid metabolism, glutathione metabolism, redox reactions, detoxification, and cellular oxidant detoxification, indicating that exogenous MT can shield edible mushrooms from Cd-induced oxidative stress. Hence, melatonin comprises various active components that selectively influence the autoxidation and antibacterial pathways during the preservation of edible mushrooms, rendering it a favorable option for their storage and preservation. Further investigation is needed to fully understand the effectiveness and best application methods of melatonin in improving the shelf life and quality of mushrooms.