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Golden thistle (Scolymus hispanicus L.) is a wild edible plant belonging to Asteraceae family, with a great potential for food applications. The aim of this study was to identify the best cooking procedure able to provide a high-quality, ready-to-use product. For this purpose, leaf midribs (the most used edible part of the plant) were cooked by boiling, steaming, and ‘sous vide’, and the cooked products were compared for their phenolic content and composition, antioxidant activity, sugar and inorganic ion content, organoleptic characteristics, and microbial safety, this latter also during storage. In general, boiling caused a decrease in the value of these parameters, despite being the best product for taste and overall acceptability. On the contrary, steaming and ‘sous vide’ resulted in the best treatments to preserve antioxidant activity, total phenols, and chlorogenic acid. In particular, in ‘sous vide’ cooked samples, a significant increase in the value of these parameters and a remarkable decrease in nitrate content were found. Moreover, ‘sous vide’ resulted in the best treatment also regarding microbial safety during shelf life; actually, after 15 days of storage at 8 °C, Enterobacteriaceae and mesophilic aerobic bacteria were not detectable in ‘sous vide’ samples. These results contributed to increase the knowledge of a wild edible plant with high nutritional properties and promoting its consumption by obtaining a ready-to-use product with good organoleptic characteristics and endowed with a long period of shelf life.

The use of biostimulants in agriculture is an emerging technique that can contribute to improved production and resource use efficiency. This research was carried out in southern Italy to evaluate the biostimulating effects of seaweed extract (SW) and azoxystrobin (AZ) on wild rocket subjected to two water regimes (WRs) and three nitrogen levels (NLs), and grown in pots under unheated greenhouse conditions. The following treatments were compared: (i) two WRs: restoration of 100% (WR100) and 50% (WR50) of crop evapotranspiration; (ii) three NLs: 0 (N0), 75 (N75), or 150 (N150) kg ha−1 of N; and (iii) three biostimulants (BSs): an untreated control (C), and the application of AZ or SW. This paper reports the effects on N uptake (Nup), N use efficiency (NUE), and water use efficiency (WUE). The following indicators of NUE were assessed: apparent recovery efficiency (RE), internal utilization efficiency (IE), partial productivity factor (PFPn) of N supplied, agronomic efficiency (AE), and physiological efficiency (PE). The following indicators of WUE were assessed: photosynthetic WUE (p_WUE), yield WUE (Y_WUE), biomass WUE (B_WUE), and irrigation yield WUE (IY_WUE). The indicators of NUE were affected differently by treatments. RE was 20% higher with SW. IE was higher with AZ. PFPn increased by 10.4 and 8.1% with AZ and SW, respectively. AE increased by 10.9 and 19.9% after applying AZ and SW, respectively. PE rose by 6.7 and 9.3% after applying AZ and SW. AZ and SW improved p_WUE, mainly under water deficit (interaction of WR × BS). With AZ application, Y_WUE, B_WUE, and IY_WUE were higher by 17.8, 13.8, and 19.3%, respectively, while the application of SW resulted in a smaller increase (9.5–7.7 and 9.9%). SW and AZ were shown to be effective through the moderate improvement of wild rocket’s nitrogen and water use efficiency. The two biostimulants were more effective at improving p_WUE in water deficit conditions, proving to be particularly useful for farmers operating with water scarcity. Therefore, they can provide valuable support to farmers by improving the sustainability of resource use.

Asparagus is highly appreciated for its organoleptic and nutritional characteristics and wild genotypes are valuable components of traditional dishes. In this study, the physical and chemical traits of wild (green and violet) and cultivated asparagus (‘Grande’, ‘Purple Passion’, and ‘Bianco di Bassano del Grappa’), both raw and steamed, were evaluated. Steaming did not affect the total phenols content with the exception of wild green (+49%) and ‘Grande’ (−31%). Only for wild violet asparagus steaming increased the total antioxidant activity (+46%). Chlorogenic acid and chicoric acid were found only in wild asparagus, while rutin was generally higher in colored cultivated asparagus than wild ones. The highest content of isorhamnetin-3-rutinoside was found in wild violet asparagus while only traces of this compound were detected in the cultivated ones. Steaming influenced the content of both chlorophylls and carotenoids in asparagus, also resulting in changes in the color parameters in cooked spears. Overall, the sugar content in wild asparagus was lower than in the cultivated ones and steaming had a low impact on this chemical trait. Principal component analysis highlighted the most evident separation between wild asparagus and cultivated ones. These results indicate that wild asparagus can be considered a nutritious and refined food, and provide specific information required for cooking process strategies in the agri-food industrial sector.

Recently, the use of biostimulant substances of different origins has been affirmed. They act differently on the physiological processes of the plant, helping to improve its productive response and resistance to biotic and abiotic stress. Therefore, the response of the wild rocket to two substances known to have biostimulating activity (Azoxystrobin, and a fluid extract of brown algae and yeast), was evaluated. Two experimental trials (Exp 1 and Exp 2) were carried out in the greenhouse. The collected product, in addition to being evaluated from a qualitative point of view, was used for evaluation of shelf life. Exp 1 involved the comparison of two N levels with two Azoxystrobin levels (treated–Azo+, and untreated control). Exp 2 involved the comparison of two N levels, and two biostimulating substances based on Azoxystrobin (Azo+) and on fluid extracts of yeast and brown algae (YBA+), in addition to untreated control. A split-plot experimental design with three replications was used. Azo+ increased marketable yield of wild rocket by 16.8% and enhanced some qualitative features at harvest as the increase in chlorophyll (+17.8%) and carotenoids (+13.5%), and decrease in nitrates (−10.6%), regardless of the nitrogen level. Furthermore, Azo+ increased the shelf life (+2.5 days) of wild rocket stored at 3.5 °C. In particular, Azo+ slowed the loss of chlorophyll (yellowing) and the worsening of odor and visual appearance. As Azoxystrobin is a fungicide effective for the control of some diseases of wild rocket, its use should be promoted as it would offer not only the benefit of disease control but also improved production and shelf life. YBA+ caused an increase in the chlorophyll content (+12.5%) at harvest of wild rocket, but reduced its antioxidant activity (−40%). YBA+ did not cause substantial variations in shelf life with the exception of a slowdown in the degradation of carotenoids. Further research is desirable to evaluate other variables such as the dose and time of application.

Smooth golden fleece (Urospermum dalechampii (L.) F.W. Schmidt) and prickly golden fleece (Urospermum picroides (L.) Scop. ex F.W. Schmid) are two wild edible plants used in traditional cuisine and folk medicine. In this research, the domestication of both species was tested for the first time using a floating system and two plant densities (412 and 824 plants m−2) to evaluate yield and quality. Some quality traits were also compared in cultivated plants and wild ones gathered in grasslands. The results show that both species are suitable for cultivation, although prickly golden fleece showed highest total phenols (132 mg 100 g−1 fresh weight—f.w.) and total antioxidant activity (0.19 mg 100 g−1 f.w.). At low sowing density, smooth golden fleece showed a nitrate content of about 7200 mg kg−1 f.w., 38% higher than plants of the same species grown at high density and plants of prickly golden fleece. These results suggest that high density can be used to optimize yield in two harvests. By permitting modulation of nutrients and a product without soil residues, the floating system used in this study proved suitable for growing U. dalechhampii and U. picroides as new vegetables for the ready-to-eat production chain.

The study aimed to assess the influence of three cooking methods (boiling, steaming, and microwave-cooking) on (i) composition in individual phenolic compounds, (ii) total phenolic content (TPC), and (iii) total antioxidant activity (TAA) of eight Mediterranean wild edible species (Asparagus acutifolius, Asphodeline lutea, Beta vulgaris, Helminthotheca echioides, Sonchus oleraceus, Taraxacum officinale, Urospermum picroides, Urtica dioica). In raw greens, several caffeic acid derivatives (chicoric, caftaric, chlorogenic, neochlorogenic, 1,5-and 3,5-dicaffeoylquinic acids) and flavonoids (glycosides of apigenin, luteolin, quercetin, isorhamnetin, kaempferol) were identified. Cooking treatments did not affect qualitative phenolic composition, while quantitative changes were recorded in some phenolic compounds and in TPC. Generally, boiling decreased TPC and TAA, while chicoric, caftaric, chlorogenic acids and quercetin-3-rutinoside increased in some species after steaming and microwave-cooking, showing positive correlation with TAA. Results confirmed steaming and microwave-cooking as mild procedures able to increase antioxidant capacity of some species, producing beneficial effects on their nutraceutical properties.

Wild rocket (Diplotaxis tenuifolia L. DC) is an emerging vegetable which market requires high-quality standards that can be obtained through appropriate cultivation techniques such as the right level of nitrogen and the application of biostimulant substances. These include strobilurins, marketed mainly as fungicides that can have complementary positive effects on the yield, quality and resources’ use efficiency of many crops. For this reason, a trial in an unheated greenhouse, in Southern Italy, to evaluate the possibility of using Azoxystrobin to improve the production of wild rocket subjected to different nitrogen inputs, was carried out. Two N levels (40 and 140 kg ha−1), Azoxystrobin-based biostimulant (Azo+) and control without Azoxystrobin (Azo−) were compared. The yield, morphological characteristics, nitrogen and water use efficiency (NUE, WUE), antioxidant activity, the content of dry matter, chlorophyll, carotenoids, phenols, and nitrates were assessed. A higher N level resulted in a 16.3% yield increase that was matched by a 12.5% reduction in NUE, 15.8, 7.3, and 16.1% increases in yield WUE (Y_WUE), biomass WUE (B_WUE), and irrigation yield WUE (IY_WUE), respectively, and a worsening of some qualitative characteristics such as a 8.5% rise in nitrates, and a decline by 11.5, 10.1, and 26.1% in the carotenoids, phenols, and antioxidant activity, respectively. Azo+ increased the yield by 10.3%, NUE by 8.9%, and Y_WUE, B_WUE, and IY_WUE, by 13.9, 9.1, and 13.8% respectively. Moreover, Azo+ improved some qualitative characteristics such as total phenols (+9.4%), chlorophyll (+15.2%), carotenoids (+9.7%), and antioxidant activity (+17.4%), while it did not affect the nitrate content. Azoxystrobin can be an additional tool available for farmers to ensure high-quality standards of wild rocket.

Ligninolytic enzymes from white-rot fungi, such as laccase (Lac) and Mn-peroxidase (MnP), are able to degrade aflatoxin B1 (AFB1), the most harmful among the known mycotoxins. The high cost of purification of these enzymes has limited their implementation into practical technologies. Every year, tons of spent mushroom substrate (SMS) are produced as a by-product of edible mushroom cultivation, such as Pleurotus spp., and disposed at a cost for farmers. SMS may still bea source of ligninolytic enzymes useful for AFB1 degradation. The in vitro AFB1-degradative activity of an SMS crude extract (SMSE) was investigated. Results show that: (1) in SMSE, high Lac activity (4 U g−1 dry matter) and low MnP activity (0.4 U g−1 dry matter) were present; (2) after 1 d of incubation at 25 °C, the SMSE was able to degrade more than 50% of AFB1, whereas after 3 and 7 d of incubation, the percentage of degradation reached the values of 75% and 90%, respectively; (3) with increasing pH values, the degradation percentage increased, reaching 90% after 3 d at pH 8. Based on these results, SMS proved to be a suitable source of AFB1 degrading enzymes and the use of SMSE to detoxify AFB1 contaminated commodities appears conceivable.

Soluble (SP), ionically bound (IBP) and covalently bound (CBP) peroxidases (POD) from artichoke leaves and heads have been characterized for the main biochemical parameters. The three PODs, in both leaves and heads, showed the major apparent catalytic efficiency (vmax,app/Km,app) towards ferulic acid, even though, in some cases, they showed higher affinity (Km,app) for other substrates. In leaves, SP and IBP showed higher Km,app for ferulic and chlorogenic acids, and CBP for ferulic and caffeic acids. In heads, SP showed higher Km,app for chlorogenic acid, IBP for caffeic and ferulic acids, and CBP for ferulic acid. It was shown that pH optimum for PODs ranged between 5.0 and 6.0 in leaves. In heads, pH optimum for SP and IBP was 5.5, while CBP presented a very low activity in a wide pH range. All PODs showed high thermal stability but different ability to regenerate: the bound forms were more able to regenerate than the soluble one. The results obtained show that (i) CBP from heads is able to work under very different cellular conditions, (ii) all PODs, in both tissues, have a high apparent catalytic efficiency for ferulic acid, which could explain the effective involvement of POD in lignin biosynthesis, (iii) in heads, high Km,app of SP for chlorogenic acid, particularly abundant in artichoke, could justify the possible involvement of PODs in browning mechanism, and (iv) in heat-processed artichoke, the ability of PODs to regenerate could contribute to oxidation and loss of product quality.

Soluble peroxidases (SP), and ionically (IBP) and covalently (CBP) bound peroxidases were extracted from leaves and edible part of artichoke heads (heart). The peroxidase (POD) forms showed a characteristic electrophoretic pattern; in particular SP and IBP forms showed nearly the same pattern, while CBP was quite different. Several basic and acid POD isoforms were present in SP and CBP forms, whereas in IBP only basic components were found. The thermal stability of different POD forms was tested at different temperatures (70, 80, 90 and 100 °C). The leaf POD forms showed greater heat stability compared to the head ones. The heat sensitivity of three POD forms was different: the bound forms were characterized by a greater heat stability than the soluble form. A series-type mathematical model has been developed to describe the inactivation kinetics of artichoke POD. The activation energies for the three POD forms of artichoke leaves and hearts were estimated by an Arrhenius-type relationship. The second step of the inactivation requires more energy to be carried out in all POD forms, especially in SP and IBP.