This work focuses on research into innovative lead-free perovskite materials to be employed as a sensitive layer for a new generation of solar cells, exploiting their potential applications in covering greenhouses to move toward an eco-friendly environment. Two types of lead-free perovskites—yellow and orange double-cation Cs2AgBiBr6, synthesized with an innovative method without chemical thinners—have been used, for the first time, as a cover for greenhouses in indoor experiments by analyzing the incident electromagnetic radiation. Two plant species, Solanum lycopersicum L. and Artemisia annua L., were cultivated indoors under controlled light, temperature, and humidity, covering the greenhouses with yellow (PY+) and orange (PO+) panels for comparison with control plants (P−) roofed by a glass panel. The growth and development parameters of all plants were investigated, referring to the aerial and root parts. Significant differences were found in terms of the plant growth parameters and photosynthetic pigments of both PY+ and PO+ compared to P− and also between them, with the yellow panel being less invasive. These results, dealing with two different plant species, confirm the feasibility of using perovskite-based panels for indoor cultivation and pave the way for outdoor application in greenhouses under sunlight.

Dittrichia viscosa is a ruderal plant species growing along roadsides and well adapting to extreme environmental conditions. D. viscosa plant tissues, especially leaves, are known to be a rich source of bioactive metabolites which have antioxidant, cytotoxic, antiproliferative and anticancer properties. Hairy root cultures are a suitable biotechnological system for investigating plant metabolic pathways and producing specialized metabolites in in vitro conditions. In this study, D. viscosa hairy root transformed lines induced by Agrobacterium rhizogenes ATCC15834 were obtained using leaf explants, and the integration of rolB and rolC genes in the genomes of transformed hairy roots were confirmed by PCR analysis. Three hairy root D. viscosa lines (DvHrT1, DvHrT4 and DvHrT5) having different phenotypic features were characterized in terms of total phenolics, flavonoids and antioxidant activity. Correlated with antioxidant activity, phenolic and flavonoid content of DvHrT1 was significantly higher than control roots and the other DvHrT lines. Our results suggest that D. viscosa hairy roots can be a valuable tool for producing various bioactive compounds having antioxidant activity and are to be further investigated to produce other specific molecules that could find application in agricultural or pharmaceutical fields.

A cell suspension culture of saffron (Crocus sativus L.) was previously established from style-derived calli to obtain an in vitro system for crocin, an uncommon and valuable water-soluble apocarotenoid, and carotenoid production suitable for future scaling up. To shed more light on the correlation between apocarotenoid biosynthesis and key-gene expression, in this study, SA was used at 0.5 mM concentration to elicit crocin production and the effects on carotenoid production were analyzed after 6, 12, 24, and 48 h. HPLC-DAD analysis was used for total crocin quantification as well as the other carotenoids zeaxanthin, β-carotene and lutein. Quantitative RT-PCR was used to analyze the transcript levels of saffron apocarotenoid biosynthetic key genes PSY (phytoene synthase), BCH1 (β-carotene hydroxylase), and CCD2 (carotenoid cleavage dioxygenase) after SA elicitation. In saffron suspension-cultured cells elicited by SA, the carotenoid biosynthetic pathway was mostly enhanced toward crocin biosynthesis, known to exert strong biological activity and therapeutic effects, rather than lutein or xanthins. SA increased BCH1 and CCD2 gene expression 15.6 and 3.3 times, respectively, compared to the control at 24 h after elicitation. Although a dynamic change of metabolite contents and gene expression was observed during the 48 h time course in response to SA elicitation, the changes of zeaxanthin and crocin were consistent with the regulation of the corresponding genes BCH and CCD2 during the time course. In conclusion, the effects of SA on regulation of gene expression in the apocarotenoid pathway could be successfully applied for the biotechnological production of crocin.

Artemisia annua L. is a herbaceous plant belonging to the Asteraceae family, known for producing, although at low levels, the sesquiterpene lactone artemisinin (AN), which is highly effective against malaria. In this study, an in vitro regeneration process of A. annua L. using ‘Artemis’ progeny was established and the potential of tissue culture for inducing new variability in terms of AN metabolism of in vitro regenerated plants was investigated. Among the plant growth regulators tested, the cytokinin 6-benzyladenine (BA) at 4.4 μM in combination with the auxin indole-butyric acid (IBA) at 0.35 μM yielded the greatest frequency of shoot induction. The optimal multiplication medium contained BA at 0.9 μM and naphthaleneacetic acid (NAA) at 0.05 μM. Regenerated plants (RPs), after transferring to the greenhouse and subsequently to the field, were analyzed during the growth cycle at different sampling times, showing a peak of AN content 20 days before blossom. Variability among different RPs and sampling times, in terms of AN and its precursors dihydroartemisinic acid (DHAA) and artemisinic acid (AA) was observed. This suggests that adventitious shoot induction could provide a useful strategy to induce variability influencing artemisinin metabolism as a consequence of in vitro manipulation.

Tomato fruit (Solanum lycopersicum L.) is one of the pillars of the Mediterranean diet. Every day it is possible to find at the market tomatoes with different shape, colour and weight, that give different nutritional intake to the human diet. Five tomato hybrids (F-1) - two "cherries" ('Juanita' and 'Sorentyno'), two red "plums" ('Apeticio' and 'Solarino'), and one yellow plum ('Maggino') - were compared in a commercial glasshouse in southern Italy. Plants were transplanted on August 23, 2019 and grown on rockwool slabs. Determinations on yield and quality of tomatoes were made on the third truss for each cultivar. 'Maggino' produced less than red plum tomatoes (345 vs. 396 g plant(-1)), and resulted the most contrasting one. Indeed, as far as carotenoids, zeaxanthin and beta cryptoxanthin were detected only in 'Maggino' (0.09 and 0.12 mg kg(-1) fresh weight (FW), respectively). Moreover, lycopene was not detected in 'Maggino' and this is the reason why a low level of lipophilic antioxidant activity was also observed. Reversely, in the other four hybrids, lycopene was present at levels ranging from 46.0 to 63.6 mg kg(-1) FW and a much higher level of lipophilic antioxidant activity was in turn observed. beta-carotene and lutein were found in all cultivars and their content ranged from 0.27 to 3.16 mg kg(-1) FW and from 0.29 to 0.47 mg kg(-1) FW, respectively. Furthermore, 'Maggino', 'Apeticio', and 'Sorentyno' showed higher levels of a-tocopherol than 'Juanita' and 'Solarino'. 'Maggino' also revealed lower levels of ascorbate compared to the other hybrids, although hydrophilic antioxidant activity did not seem to be affected, likely due to the total phenolic levels which were not reduced in this cultivar. 'Maggino' fruits also showed reduced total soluble solids and dry matter compared to the red fruits.

Plant specialized metabolites (SMs) play an important role in the interaction with the environment and are part of the plant defense response. These natural products are volatile, semi-volatile and non-volatile compounds produced from common building blocks deriving from primary metabolic pathways and rapidly evolved to allow a better adaptation of plants to environmental cues. Specialized metabolites include terpenes, flavonoids, alkaloids, glucosinolates, tannins, resins, etc. that can be used as phytochemicals, food additives, flavoring agents and pharmaceutical compounds. This review will be focused on Mediterranean crop plants as a source of SMs, with a special attention on the strategies that can be used to modulate their production, including abiotic stresses, interaction with beneficial soil microorganisms and novel genetic approaches.

One of the challenges for agriculture in the coming years will be producing more food avoiding reducing the nutritional values of fruits and vegetables, sources of nutraceutical compounds. It has been demonstrated that light-emitting diodes (LEDs) used as a supplementary light (SL) technology improve tomato yield in Mediterranean greenhouses, but few data have been reported about SL effects on fruit physio-chemical parameters. In this study, three tomato hybrid (F1) cultivars were grown for year-round production in a commercial semi-closed glasshouse in Southern Italy: red cherry type ("Sorentyno"), red plum type ("Solarino"), and yellow plum type ("Maggino"). From 120 to 243 days after transplant (DAT), Red/White/Blue LEDs were used as SL. The fruits harvested 180 DAT were analyzed and those obtained under LEDs had 3% more dry weight, 15% more total soluble solids, and 16% higher titratable acidity than fruits grown only under natural light. Generally, the antioxidant activity and the mineral profile of the fruits were not negatively influenced by SL. Lycopene content was unchanged and vitamin C content of "Sorentyno" even increased by 15% under LEDs. Overall, LEDs used as SL technology could be one of the tools used by agriculture in Mediterranean basin to produce more food maintaining high quality production.

Artemisia annua L. is well-known as the plant source of artemisinin, a sesquiterpene lactone with effective antimalarial activity. Here, a putative ortholog of the Arabidopsis thaliana WRKY40 transcription factor (TF) was isolated via reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends in A. annua and named AaWRKY40. A putative nuclear localization domain was identified in silico and experimentally confirmed by using protoplasts of A. annua transiently transformed with AaWRKY40-GFP. A genome-wide analysis identified 122 WRKY genes in A. annua, and a manually curated database was obtained. The deduced proteins were categorized into the major WRKY groups, with group IIa containing eight WRKY members including AaWRKY40. Protein motifs, gene structure, and promoter regions of group IIa WRKY TFs of A. annua were characterized. The promoter region of AaWRKY group IIa genes contained several abiotic stress cis-acting regulatory elements, among which a highly conserved W-box motif was identified. Expression analysis of AaWRKY40 compared to AaWRKY1 in A. annua cell cultures treated with methyl jasmonate known to enhance artemisinin production, suggested a possible involvement of AaWRKY40 in terpenoid metabolism. Further investigation is necessary to study the role of AaWRKY40 and possible interactions with other TFs in A. annua.

The production of crocin, an uncommon and valuable apocarotenoid with strong biological activity, was obtained in a cell suspension culture of saffron (Crocus sativus L.) established from style-derived calli to obtain an in-vitro system for metabolite production. Salycilic acid (SA) was used at different concentrations to elicit metabolite production, and its effect was analyzed after a 4 days of treatment. HPLC-DAD analysis was used for total crocin quantification while the Folin-Ciocâlteu method was applied for phenolic compounds (PC) content. Interestingly, despite cell growth inhibition, a considerable exudation was observed when the highest SA concentration was applied, leading to a 7-fold enhanced production of crocin and a 4-fold increase of phenolics compared to mock cells. The maximum antioxidant activity of cell extracts was evidenced after SA 0.1 mM elicitation. Water-soluble extracts of saffron cells at concentrations of 1, 0.5, and 0.1 µg mL−1 showed significant inhibitory effects on MDA-MB-231 cancer cell viability. The heterologous vacuolar markers RFP-SYP51, GFPgl133Chi, and AleuRFP, were transiently expressed in protoplasts derived from the saffron cell suspensions, revealing that SA application caused a rapid stress effect, leading to cell death. Cell suspension elicitation with SA on the 7th day of the cell growth cycle and 24 h harvest time was optimized to exploit these cells for the highest increase of metabolite production in saffron cells.

Heat stress (HS), causing impairment in several physiological processes, is one of the most damaging environmental cues for plants. To counteract the harmful effects of high temperatures, plants activate complex signalling networks, indicated as HS response (HSR). Expression of heat shock proteins (HSPs) and adjustment of redox homeostasis are crucial events of HSR, required for thermotolerance. By pharmacological approaches, the involvement of cAMP in triggering plant HSR has been recently proposed. In this study, to investigate the role of cAMP in HSR signalling, tobacco BY-2 cells overexpressing the 'cAMP-sponge', a genetic tool that reduces intracellular cAMP levels, have been used. in vivo cAMP dampening increased HS susceptibility in a HSPs-independent way. The failure in cAMP elevation during HS caused a high accumulation of reactive oxygen species, due to increased levels of respiratory burst oxidase homolog D, decreased activities of catalase and ascorbate peroxidase, as well as down-accumulation of proteins involved in the control of redox homeostasis. In addition, cAMP deficiency impaired proteasome activity and prevented the accumulation of many proteins of ubiquitin-proteasome system (UPS). By a large-scale proteomic approach together with in silico analyses, these UPS proteins were identified in a specific cAMP-dependent network of HSR.

This review is dedicated to the memory of Prof. Domenico Mariotti, who significantly contributed to establishing the Italian research community in Agricultural Genetics and carried out the first experiments of Agrobacterium-mediated plant genetic transformation and regeneration in Italy during the 1980s. Following his scientific interests as guiding principles, this review summarizes the recent advances obtained in plant biotechnology and fundamental research aiming to: (i) Exploit in vitro plant cell and tissue cultures to induce genetic variability and to produce useful metabolites; (ii) gain new insights into the biochemical function of Agrobacterium rhizogenes rol genes and their application to metabolite production, fruit tree transformation, and reverse genetics; (iii) improve genetic transformation in legume species, most of them recalcitrant to regeneration; (iv) untangle the potential of KNOTTED1-like homeobox (KNOX) transcription factors in plant morphogenesis as key regulators of hormonal homeostasis; and (v) elucidate the molecular mechanisms of the transition from juvenility to the adult phase in Prunus tree species.

Crocus sativus L., mostly famous as saffron, has gained more attention due to its crocin (crocetin ester) pigment responsible for its extensive pharmaceutical properties. In this study, we established two different callus cultures from corm and style explants of saffron to find out the best explant as a suitable source for crocin production. Comparative analyses of total phenolic, flavonoid, carotenoid and anthocyanin contents were also performed in the two callus cultures. For callus induction, different combinations of MS medium with name thidiazuron (TDZ), benzylaminopurine (BA), 1-naphthaleneacetic acid (NAA), and 2,4-dichlorophenoxyacetic acid (2,4-D) alone or in combination were tested. Of the used media, all the combinations containing TDZ and NAA gave 100% callus induction. HPLC-DAD and HPLC–ESI-MS analysis were used for identification of crocin esters in established callus cultures. The highest amount of 0.35 mg g−1 DW crocin was detected in style originated calli grown on the medium containing 3 mg L−1 NAA + 1 mg L−1 TDZ while the corm calli showed the most abundant total carotenoid (0.73 mg g−1 DW), phenolic (15.04 mg gallic acid equivalent g−1 DW) and flavonoid (0.76 mg rutin equivalent g−1 DW) contents. In general, style-derived calli showed longer time survival with a fine texture and good quality compared to corm-derived calli.

Asparagus represents a nutritious and refined food being very popular to consumers. The effects on the quality of spears cooked by conventional (boiling, steaming and microwaving) and different sous vide (using hot water or microwave) methods were analyzed. Physical, chemical and sensory traits were compared. Microwaving caused the largest weight change, the highest dry weight increase and the highest Total Color Difference in cooked samples compared to raw asparagus spears. Sous vide-microwaving showed an increase in greenness (the highest value of h degrees), better than the raw spears, and the lowest reduction in chlorophyll contents. After sous vide microwawing violaxanthin increased by about 42%, while after steaming neoaxanthin decreased by about 57%. Following sensory analysis, all cooked samples generally resulted acceptable (scores > 5 In a 1-9 hedonic scale), nevertheless sous vide-microwaved asparagus satisfied consumer acceptability more than the other cooked samples, especially when compared to steamed samples. Results indicate the sous vide-microwaving technique as optimal to preserve several traits, including the organoleptic ones, essential for the quality of cook-chilled asparagus spears. They also provide product-specific information usually required for cooking process strategies In the industrial area of ready-to-eat vegetables.

Stimulated production of secondary phenolic metabolites and proline was studied by using cell cultures of artichoke [Cynara cardunculus L. subsp. scolymus (L.) Hayek] submitted to nutritional stress. Artichoke cell cultures accumulated phenolic secondary metabolites in a pattern similar to that seen in artichoke leaves and heads (capitula). This paper shows that both callus and cell suspension cultures under nutritional stress accumulated phenolic compounds and proline, at the same time their biomass production was negatively affected by nutrient deficiency. The results obtained strongly suggest that plant tissues respond to nutrient deprivation by a defensive costly mechanism, which determines the establishment of a mechanism of trade-off between growth and adaptive response. Furthermore, the results of this research suggest that perception of abiotic stress and increased phenolic metabolites are linked by a sequence of biochemical processes that also involves the intracellular free proline and the oxidative pentose phosphate pathway. The main conclusion of this paper is that, once calli and cell suspension cultures respond to nutrient deficiency, in acclimated cells the establishment of a negative correlation between primary metabolism (growth) and secondary metabolism (defence compounds) is observed.

Plant cell cultures are valuable tools for the production of bioactive compounds. Recently, many efforts have been made in order to develop and optimize strategies for increasing the yields of the desired plant metabolites by eliciting their biosynthesis or improving the efficiency of product recovery. We established Artemisia annua L. (Asteraceae) cell suspension cultures to investigate the biosynthesis of the antimalarial artemisinin (AN) [1] and other healthful phytochemicals such as carotenoids and quinones. The use of culture supplementation with cyclic oligomers β-cyclodextrins was successful to significantly increase intracellular and extracellular levels of AN, lutein, Q9 and Q10 [2,3]. In order to investigate the mechanism underlying these effects, other oligosaccharides having a linear structure were explored as putative elicitors in A. annua cell suspension cultures. For this purpose, oligogalacturonides (OGA) were obtained by hydrolysis of polygalacturonic acid with pectolyase from Aspergillus japonicus. Various OGA fractions were used for culture medium supplementation at different concentrations. The results showed that the 4 – 5 OGA fraction induced significant increases of AN and the intermediate dihydroartemisinic acid. These results suggest that the ability of β-CDs to elicit the production of bioactive compounds in A. annua cell cultures could be due to their chemical similarity to pectic oligosaccharides often occurring in plants after fungal infection.

Sea fennel (Crithmum maritimum L.) is a perennial halophyte species typical of coastal ecosystems, used fresh in traditional cuisine and folk medicine due to its sensory properties and a good content of healthy compounds. Although considered as a promising biosaline crop, this halophyte is underutilized for commercial cultivation possibly due to a shortage of its consumer demand. For promoting a full exploitation of this species, a new food product was obtained by drying sea fennel using different treatments (air-drying, microwave-drying, microwave-assisted air-drying and freeze-drying). Water activity, essential oil content, chlorophylls, surface colour, colouring power and sensory evaluation were analyzed. All drying treatments allow to obtain a good water activity but significantly reduced the content of essential oils and chlorophylls. Freeze-drying and microwaving preserved the surface colour parameters more than other drying treatments, while freeze-drying gave the product the best colouring power. Based on sensory analysis, microwave-drying, microwave-assisted air-drying and freeze-drying showed the highest scores among the drying methods. Taken together the results indicate that microwaving and freeze-drying are optimal for preserving qualitative traits, including organoleptic properties, in dried sea fennel for food use. Furthermore, dried sea fennel can be usefully exploited in human food not only for its aromatic traits but also for its food colouring power like other plant derived natural colorants. It could be concluded that this underutilized crop could play a better role for making up a sustainable food production system.

Plants can frequently experience low oxygen concentrations due to environmental factors such as flooding or waterlogging. It has been reported that both anoxia and the transition from anoxia to re-oxygenation determine a strong imbalance in the cellular redox state involving the production of reactive oxygen species (ROS) and nitric oxide (NO). Plant cell cultures can be a suitable system to study the response to oxygen deprivation stress since a close control of physicochemical parameters is available when using bioreactors. For this purpose, Arabidopsis cell suspension cultures grown in a stirred bioreactor were subjected to a severe anoxic stress and analyzed during anoxia and re-oxygenation for alteration in ROS and NO as well as in antioxidant enzymes and metabolites. The results obtained by confocal microscopy showed the dramatic increase of ROS, H2O2, and NO during the anoxic shock. All the ascorbate-glutathione related parameters were altered during anoxia but restored during re-oxygenation. Anoxia also induced a slight but significant increase of α-tocopherol levels measured at the end of the treatment. Overall, the evaluation of cell defenses during anoxia and re-oxygenation in Arabidopsis cell cultures revealed that the immediate response involving the overproduction of reactive species activated the antioxidant machinery including ascorbate-glutathione system, α-tocopherol and the ROS-scavenging enzymes ascorbate peroxidase, catalase, and peroxidase making cells able to counteract the stress toward cell survival.

Wheat bran is generally considered a byproduct of the flour milling industry, but it is a great source of fibers, minerals, and antioxidants that are important for human health. Phenolic acids are a specific class of wheat bran components that may act as antioxidants to prevent heart disease and to lower the incidence of colon cancer. Moreover, phenolic acids have anti-inflammatory properties that are potentially significant for the promotion of gastrointestinal health. Evidence on the beneficial effects of phenolic acids as well as of other wheat bran components is encouraging the use of wheat bran as an ingredient of functional foods. After an overview of the chemistry, function, and bioavailability of wheat phenolic acids, the discussion will focus on how technologies can allow the formulation of new, functional whole wheat products with enhanced health-promoting value and safety without renouncing the good-tasting standards that are required by consumers. Finally, this review summarizes the latest studies about the stability of phenolic acids in wheat foods fortified by the addition of wheat bran, pearled fractions, or wheat bran extracts.

In this study, the quali-quantitative composition of hydrophilic (phenolic acids) and lipophilic (isoprenoids) extracts from whole-meal flour of five elite Italian durum wheat cultivars was determined. Significant differences in the content of bioactive compounds were observed among the wheat extracts, in particular concerning the content of bound phenolic acids, lutein and β-tocotrienols. The cultivars Duilio and Svevo showed the highest amount of phenolic acids and isoprenoids, respectively. Extracts were evaluated for their anti-inflammatory activity on HT-29 human colon cells by measuring the levels of interleukin 8 (IL-8) and transforming growth factor β1 (TGF-β1). Durum wheat extracts significantly inhibited the secretion of the pro-inflammatory IL-8 mediator at 66 µg/mL of phenolic acids and at 0.2 µg/mL of isoprenoids. Conversely, the secretion of the anti-inflammatory mediator TGF-β1 was not modified by neither hydrophilic nor lipophilic extracts. These results provide further insight into the potential of durum wheat on human health suggesting the significance of varieties with elevated contents of bioactive components.

Higher plants synthesize an amazing diversity of phenolic secondary metabolites. Phenolics are defined secondary metabolites or natural products because, originally, they were considered not essential for plant growth and development. Plant phenolics, like other natural compounds, provide the plant with specific adaptations to changing environmental conditions and, therefore, they are essential for plant defense mechanisms. Plant defensive traits are costly for plants due to the energy drain from growth toward defensive metabolite production. Being limited with environmental resources, plants have to decide how allocate these resources to various competing functions. This decision brings about trade-offs, i.e., promoting some functions by neglecting others as an inverse relationship. Many studies have been carried out in order to link an evaluation of plant performance (in terms of growth rate) with levels of defense-related metabolites. Available results suggest that environmental stresses and stress-induced phenolics could be linked by a transduction pathway that involves: (i) the proline redox cycle; (ii) the stimulated oxidative pentose phosphate pathway; and, in turn, (iii) the reduced growth of plant tissues.