Effects of Corm Treatment with Cold Plasma and Electromagnetic Field on Growth and Production of Saffron Metabolites in Crocus sativus.

Crocus sativus L. is a widely cultivated traditional plant for obtaining dried red stigmas known as "saffron," the most expensive spice in the world. The response of C. sativus to pre-sowing processing of corms with cold plasma (CP, 3 and 5 min), vacuum (3 min), and electromagnetic field (EMF, 5 min) was assessed to verify how such treatments affect plant performance and the quality and yield of herbal raw materials. The results show that applied physical stressors did not affect the viability of corms but caused stressor-dependent changes in the kinetics of sprouting, growth parameters, leaf trichome density, and secondary metabolite content in stigmas. The effect of CP treatment on plant growth and metabolite content was negative, but all stressors significantly (by 42-74%) increased the number of leaf trichomes. CP3 treatment significantly decreased the length and dry weight of flowers by 43% and 60%, respectively, while EMF treatment increased the length of flowers by 27%. However, longer CP treatment (5 min) delayed germination. Vacuum treatment improved the uniformity of germination by 28% but caused smaller changes in the content of stigma compounds compared with CP and EMF. Twenty-six compounds were identified in total in Crocus stigma samples by the HPLC-DAD method, including 23 crocins, rutin, picrocrocin, and safranal. Processing of Crocus corms with EMF showed the greatest efficiency in increasing the production of secondary metabolites in saffron. EMF increased the content of marker compounds in stigmas (crocin 4: from 8.95 to 431.17 mg/g; crocin 3: from 6.27 to 164.86 mg/g; picrocrocin: from 0.4 to 1.0 mg/g), although the observed effects on growth were neutral or slightly positive. The obtained findings indicate that treatment of C. sativus corms with EMF has the potential application for increasing the quality of saffron by enhancing the amounts of biologically active compounds.

Distribution of Main Bioactive Compounds from Saffron Species as a Function of Infusion Temperature and Time in an Oil/Water System.

Most research on saffron has focused on its composition and beneficial effects, while the culinary perspective to enhance its gastronomic potential remains unexplored. This study aims to define the transfer of the main compounds responsible for color, flavor, and aromatic properties, evaluating three critical variables: temperature (60 °C, 80 °C and 100 °C), infusion time (ranging from 10 to 30 min), and the composition of the medium (water, oil, and water/oil). Samples were analyzed using the LC-QTOF MS/MS and ISO 3632-1:2011 methods. The major compounds were crocins, including trans-crocin and picrocrocin. Among the flavonoids, kaempferol 3-O-sophoroside stands out. Regarding extraction conditions, crocins, glycoside flavonoids, and picrocrocin were enhanced in water, the former in 100% water and at low temperatures, while picrocrocin proved to be the most stable compound with extraction favored at high temperatures. The variable with the greatest incidence of picrocrocin isolation seemed to be the concentration of water since water/oil compositions reported higher concentrations. Safranal and kaempferol were enriched in the oil phase and at lower temperatures. This study provides a chemical interpretation for the appropriate gastronomic use of saffron according to its versatility. Finally, the determination of safranal using the ISO method did not correlate with that obtained using chromatography.

A Picrocrocin-Enriched Fraction from a Saffron Extract Affects Lipid Homeostasis in HepG2 Cells through a Non-Statin-like Mode.

Dyslipidemia is a lipid metabolism disorder associated with the loss of the physiological homeostasis that ensures safe levels of lipids in the organism. This metabolic disorder can trigger pathological conditions such as atherosclerosis and cardiovascular diseases. In this regard, statins currently represent the main pharmacological therapy, but their contraindications and side effects limit their use. This is stimulating the search for new therapeutic strategies. In this work, we investigated in HepG2 cells the hypolipidemic potential of a picrocrocin-enriched fraction, analyzed by high-resolution 1H NMR and obtained from a saffron extract, the stigmas of Crocus sativus L., a precious spice that has already displayed interesting biological properties. Spectrophotometric assays, as well as expression level of the main enzymes involved in lipid metabolism, have highlighted the interesting hypolipidemic effects of this natural compound; they seem to be exerted through a non-statin-like mechanism. Overall, this work provides new insights into the metabolic effects of picrocrocin, thus confirming the biological potential of saffron and paving the way for in vivo studies that could validate this spice or its phytocomplexes as useful adjuvants in balancing blood lipid homeostasis.

Effective Isolation of Picrocrocin and Crocins from Saffron: From HPTLC to Working Standard Obtaining.

Saffron is widely cultivated and used as a spice. Recently published data on the chemical composition and pharmacological potential of saffron determine its use in pharmacy and medicine. The proposed high-performance thin-layer chromatography (HPTLC) method allows good separation of 11 analytes. The saffron quality (Iran, Ukraine, Spain, Morocco samples) assessment was based on the European Pharmacopoeia monograph and ISO 3632. The HPTLC method for the safranal, crocin, and picrocrocin quantification was proposed and validated. The crocins content in Ukrainian saffron was from 17.80% to 33.25%. Based on qualitative and quantitative assessment results, the saffron sample from Zaporizhzhia (Ukraine) had the highest compounds content and was chosen to obtain the working standards of picrocrocin and crocins (trans-4GG, trans-2G, trans-3Gg) by preparative chromatography. The compounds were isolated from lyophilized extract of saffron using a Symmetry Prep C18 column (300 × 19 mm × 7 µm), and identified by spectroscopic techniques (HPLC-DAD, UPLC-ESI-MS/MS). The purity of crocins and picrocrocin was more than 97%. A novel method proposed to obtain working standards is simple and reproducible for the routine analysis of saffron quality control.

Cow and Ewe Cheeses Made with Saffron: Characterization of Bioactive Compounds and Their Antiproliferative Effect in Cervical Adenocarcinoma (HeLa) and Breast Cancer (MDA-MB-231) Cells.

Saffron is a widespread consumed spice containing many phytochemicals. It is often used in dairy technologies to enhance color and flavor of cheeses, but it is also known for its several therapeutic effects, as well as its antiproliferative and anticancer properties. In this study High Performance Liquid Chromatography was used to characterize saffron bioactive compounds in cow and ewe cheeses made with saffron, and the antiproliferative effect of the crocin-rich extracts from cheeses was investigated on different cellular lines (CaCo2, MDA-MB-231 and HeLa) by MTT assay. Crocins were observed in all cheese samples, with the total content ranging between 0.54 and 30.57 mg trans-4-GG/100 g cheese, according to the different cheese making process. Picrocrocin was detected in no cheese (probably due to its degradation during cheese making), while safranal was detected only in one ewe cheese (mainly due to its high volatility). HeLa and MDA-MB-231 cells were sensitive to treatment with crocin-rich extracts from cheeses, while no effect was observed on CaCo2 cells. The chemical environment of the food matrix seems to have a great influence on the crocin antiproliferative effect: the crocin-rich extracts from cheese with both high residual N/protein and fat contents showed increased antiproliferative effect compared to pure crocin (trans-4-GG), but cheeses from different milk species (type of fats and proteins) could also play an important role in modulating crocin's antiproliferative effects.

Identification and characterization of apocarotenoid modifiers and carotenogenic enzymes for biosynthesis of crocins in Buddleja davidii flowers.

Crocetin biosynthesis in Buddleja davidii flowers proceeds through a zeaxanthin cleavage pathway catalyzed by two carotenoid cleavage dioxygenases (BdCCD4.1 and BdCCD4.3), followed by oxidation and glucosylation reactions that lead to the production of crocins. We isolated and analyzed the expression of 12 genes from the carotenoid pathway in B. davidii flowers and identified four candidate genes involved in the biosynthesis of crocins (BdALDH, BdUGT74BC1, BdUGT74BC2, and BdUGT94AA3). In addition, we characterized the profile of crocins and their carotenoid precursors, following their accumulation during flower development. Overall, seven different crocins, crocetin, and picrocrocin were identified in this study. The accumulation of these apocarotenoids parallels tissue development, reaching the highest concentration when the flower is fully open. Notably, the pathway was regulated mainly at the transcript level, with expression patterns of a large group of carotenoid precursor and apocarotenoid genes (BdPSY2, BdPDS2, BdZDS, BdLCY2, BdBCH, BdALDH, and BdUGT Genes) mimicking the accumulation of crocins. Finally, we used comparative correlation network analysis to study how the synthesis of these valuable apocarotenoids diverges among B. davidii, Gardenia jasminoides, and Crocus sativus, highlighting distinctive differences which could be the basis of the differential accumulation of crocins in the three species.

Quantification of crocin, picrocrocin and safranal in saffron stigmas obtained from sounded corms with acoustic waves.

INTRODUCTION: Plant acoustic frequency technology (PAFT) is the effect or treatment of a plant with a specific frequency sound wave. OBJECTIVE: The sound waves with different frequencies and a sound pressure level 77 dB were emitted on the saffron corms in a controlled environment using aeroponic cultivation and the contents of crocin, picrocrocin and safranal in their produced stigmas were analysed by high-performance liquid chromatography. For this purpose, the corms were divided into two groups. In group 1, sound waves with the frequencies of 0.5, 1 and 2 kHz were emitted on saffron corms in different stages of sprouting, flowering and the whole stage of sprouting and flowering. In group 2, sonication was performed on the corms during the flowering stage at 4, 8, 12 and 16 kHz frequencies. RESULTS: The changes in the contents of crocin, picrocrocin and safranal were not significantly compared to the control at 0.5, 1 and 2 kHz frequencies in the stages of sprouting and flowering of corms. While the higher frequencies (4, 8, 12 and 16 kHz) in flowering stage were affected significantly, the crocin and picrocrocin content increased 8.5% and 30%, applying the frequency of 12 and 8 kHz, respectively. Also, the effect of sound exposure time per day with the frequency of 16 kHz at 15, 30 and 60 min were investigated. CONCLUSION: The findings showed that the corms could be affected by sounding in the different stages of growth of the corm and also in the content of secondary metabolites.

Bioanalytical Method Development and Validation Study of Neuroprotective Extract of Kashmiri Saffron Using Ultra-Fast Liquid Chromatography-Tandem Mass Spectrometry (UFLC-MS/MS): In Vivo Pharmacokinetics of Apocarotenoids and Carotenoids.

Kashmir saffron (Crocus sativus L.), also known as Indian saffron, is an important Asian medicinal plant with protective therapeutic applications in brain health. The main bioactive in Kashmir or Indian Saffron (KCS) and its extract (CSE) are apocarotenoids picrocrocin (PIC) and safranal (SAF) with carotenoids, crocetin esters (crocins), and crocetins. The ultra-fast liquid chromatography(UFLC)- photodiode array standardization confirmed the presence of biomarkers PIC, trans-4-GG-crocin (T4C), trans-3-Gg-crocin (T3C), cis-4-GG-crocin (C4C), trans-2-gg-crocin (T2C), trans-crocetin (TCT), and SAF in CSE. This study's objectives were to develop and validate a sensitive and rapid UFLC-tandem mass spectrometry method for PIC and SAF along T4C and TCT in rat plasma with internal standards (IS). The calibration curves were linear (R2 > 0.990), with the lower limit of quantification (LLOQ) as 10 ng/mL. The UFLC-MS/MS assay-based precision (RSD, <15%) and accuracy (RE, -11.03-9.96) on analytical quality control (QC) levels were well within the acceptance criteria with excellent recoveries (91.18-106.86%) in plasma samples. The method was applied to investigate the in vivo pharmacokinetic parameters after oral administration of 40 mg/kg CSE in the rats (n = 6). The active metabolite TCT and T4C, PIC, SAF were quantified for the first time with T3C, C4C, T2C by this validated bioanalytical method, which will be useful for preclinical/clinical trials of CSE as a potential neuroprotective dietary supplement.

Efficient production of saffron crocins and picrocrocin in Nicotiana benthamiana using a virus-driven system.

Crocins and picrocrocin are glycosylated apocarotenoids responsible, respectively, for the color and the unique taste of the saffron spice, known as red gold due to its high price. Several studies have also shown the health-promoting properties of these compounds. However, their high costs hamper the wide use of these metabolites in the pharmaceutical sector. We have developed a virus-driven system to produce remarkable amounts of crocins and picrocrocin in adult Nicotiana benthamiana plants in only two weeks. The system consists of viral clones derived from tobacco etch potyvirus that express specific carotenoid cleavage dioxygenase (CCD) enzymes from Crocus sativus and Buddleja davidii. Metabolic analyses of infected tissues demonstrated that the sole virus-driven expression of C. sativus CsCCD2L or B. davidii BdCCD4.1 resulted in the production of crocins, picrocrocin and safranal. Using the recombinant virus that expressed CsCCD2L, accumulations of 0.2% of crocins and 0.8% of picrocrocin in leaf dry weight were reached in only two weeks. In an attempt to improve apocarotenoid content in N. benthamiana, co-expression of CsCCD2L with other carotenogenic enzymes, such as Pantoea ananatis phytoene synthase (PaCrtB) and saffron ß-carotene hydroxylase 2 (BCH2), was performed using the same viral system. This combinatorial approach led to an additional crocin increase up to 0.35% in leaves in which CsCCD2L and PaCrtB were co-expressed. Considering that saffron apocarotenoids are costly harvested from flower stigma once a year, and that Buddleja spp. flowers accumulate lower amounts, this system may be an attractive alternative for the sustainable production of these appreciated metabolites.

Bioactivity and Bioavailability of the Major Metabolites of Crocus sativus L. Flower.

Crocus sativus L. has been cultivated throughout history to obtain its flowers, whose dried stigmas give rise to the spice known as saffron. Crocetin esters, picrocrocin, and safranal are the main metabolites of this spice, which possess a great bioactivity, although the mechanisms of action and its bioavailability are still to be solved. The rest of the flower is composed by style, tepals, and stamens that have other compounds, such as kaempferol and delphinidin, which have an important antioxidant capacity, and these can be applied in foods, phytopharmaceuticals, and cosmetics. The aim of this work was to provide an updated and critical review of the research on the main compounds of Crocus sativus L. flower, including the adequate analytical methods for their identification and quantification, with a focus on their bioactivity and bioavailability.

Latest advances in the extraction and determination of saffron apocarotenoids.

Saffron, the dried red stigmas of Crocus sativus L. plant, is the most expensive spice in the world. It is highly valued not only for the color and flavor that exerts to various foods and drinks but also for its functional properties. Various classes of apocarotenoids such as crocetin sugar esters, picrocrocin and safranal are responsible for these characteristics. In the present review, the evolution of the methods proposed by the ISO standard for extraction and determination of saffron apocarotenoids since 1980 is presented in parallel to other approaches proposed by various scientists to overcome limitations of the standard. Moreover, the latest advances regarding applications of novel extraction techniques and powerful analytical tools that require limited or no sample preparation are critically discussed.

Saffron: An Old Medicinal Plant and a Potential Novel Functional Food.

The spice saffron is made from the dried stigmas of the plant Crocus sativus L. The main use of saffron is in cooking, due to its ability to impart colour, flavour and aroma to foods and beverages. However, from time immemorial it has also been considered a medicinal plant because it possesses therapeutic properties, as illustrated in paintings found on the island of Santorini, dated 1627 BC. It is included in Catalogues of Medicinal Plants and in the European Pharmacopoeias, being part of a great number of compounded formulas from the 16th to the 20th centuries. The medicinal and pharmaceutical uses of this plant largely disappeared with the advent of synthetic chemistry-produced drugs. However, in recent years there has been growing interest in demonstrating saffron's already known bioactivity, which is attributed to the main components-crocetin and its glycosidic esters, called crocins, and safranal-and to the synergy between the compounds present in the spice. The objective of this work was to provide an updated and critical review of the research on the therapeutic properties of saffron, including activity on the nervous and cardiovascular systems, in the liver, its antidepressant, anxiolytic and antineoplastic properties, as well as its potential use as a functional food or nutraceutical.

Effect of split foliar fertilisation on the quality and quantity of active constituents in saffron (Crocus sativus L.).

BACKGROUND: Saffron (Crocus sativus L.) is one of the most expensive medicinal and aromatic plants in the world. Due to the excessive application of chemical fertilisers in saffron farms and alkalinity of most cultivated soils, split foliar fertilisation has been suggested. The primary goal of this study was to propose split foliar fertilisation as a technique in increasing the quality and quantity of active constituents in saffron. HPLC analysis was used to quantify the most important saffron components; crocins (colour), picrocrocin (taste), and safranal (odour). This study was carried out in Kashmar, Iran, to determine the effect of split foliar fertilisations on quality and quantity of saffron in 2011 and 2012. A split-plot design experiment based on randomised complete block with three replications was conducted to examine three fertiliser types in three regimes for split foliar fertilisation. RESULTS: Statistical analysis showed that split foliar fertilisation and the fertiliser type significantly increased saffron yield, number of flowers and crocin; whereas it decreased the picrocrocin and safranal content of the saffron stigmas (P < 0.05). CONCLUSION: Overall, split foliar fertilisation increased saffron yield and colour but decreased the taste and the odour of saffron.

Saffron, a Potential Bridge between Nutrition and Disease Therapeutics: Global Health Challenges and Therapeutic Opportunities.

Plants are an important source of essential bioactive compounds that not only have a beneficial role in human health and nutrition but also act as drivers for shaping gut microbiome. However, the mechanism of their functional attributes is not fully understood despite their significance. One such important plant is Crocus sativus, also known as saffron, which possesses huge medicinal, nutritional, and industrial applications like food and cosmetics. The importance of this plant is grossly attributed to its incredible bioactive constituents such as crocins, crocetin, safranal, picrocrocin, and glycosides. These bioactive compounds possess a wide range of therapeutic activities against multiple human ailments. Since a huge number of studies have revealed negative unwanted side effects of modern-day drugs, the scientific communities at the global level are investigating a large number of medicinal plants to explore natural products as the best alternatives. Taken into consideration, the available research findings indicate that saffron has a huge scope to be further explored to establish alternative natural-product-based drugs for health benefits. In this review, we are providing an update on the role of bioactive compounds of saffron as therapeutic agents (human disorders and antimicrobial activity) and its nutritional values. We also highlighted the role of omics and metabolic engineering tools for increasing the content of key saffron bioactive molecules for its mass production. Finally, pre-clinical and clinical studies seem to be necessary to establish its therapeutic potential against human diseases.

On the Importance of the Starting Material Choice and Analytical Procedures Adopted When Developing a Strategy for the Nanoencapsulation of Saffron (Crocus sativus L.) Bioactive Antioxidants.

Saffron is known as the most expensive spice in the world. It is comprised of the dried stigmas of the pistil of the Crocus sativus L., which is a cultivated, sterile crocus plant. This plant material is now recognized as the unique edible source of certain bioactive apocarotenoids for which in-vivo antioxidant properties have been reported. Among the latter, crocins, red-orange natural colorants, and their parent molecule crocetin prevail in bioactivity significance. This review is focused on the strategies developed so far for their nanoencapsulation in relation to the characteristics of the starting material, extraction procedures of the bioactive antioxidants and analytical methods applied for their characterization and quantification throughout the process. The literature so far points out gaps that lead to publishable data, on one hand, but not necessarily to repeatable and meaningful processes due to incomplete characterization of the starting and the released material in efficiency and stability studies of the nanoencapsulates. Accurate terminology and quantitative chromatographic or spectrophotometric procedures for the determination of the core compounds are needed. Authenticity control and quality of saffron samples, and the verification of the concentrations of compounds in commercial preparations labeled as 'crocin,' are prerequisites in any experimental design setup.

Production of Saffron Apocarotenoids in Nicotiana benthamiana Plants Genome-Edited to Accumulate Zeaxanthin Precursor.

Crocins are glycosylated apocarotenoids with strong coloring power and anti-oxidant, anticancer, and neuro-protective properties. We previously dissected the saffron crocin biosynthesis pathway, and demonstrated that the CsCCD2 enzyme, catalyzing the carotenoid cleavage step, shows a strong preference for the xanthophyll zeaxanthin in vitro and in bacterio. In order to investigate substrate specificity in planta and to establish a plant-based bio-factory system for crocin production, we compared wild-type Nicotiana benthamiana plants, accumulating various xanthophylls together with α- and ß-carotene, with genome-edited lines, in which all the xanthophylls normally accumulated in leaves were replaced by a single xanthophyll, zeaxanthin. These plants were used as chassis for the production in leaves of saffron apocarotenoids (crocins, picrocrocin) using two transient expression methods to overexpress CsCCD2: agroinfiltration and inoculation with a viral vector derived from tobacco etch virus (TEV). The results indicated the superior performance of the zeaxanthin-accumulating line and of the use of the viral vector to express CsCCD2. The results also suggested a relaxed substrate specificity of CsCCD2 in planta, cleaving additional carotenoid substrates.

Effect of Soil Composition on Secondary Metabolites of Moroccan Saffron (Crocus sativus L.).

Climate and soil are important factors that affect the quality of saffron. Saffron quality is determined by the marked content of secondary metabolites. The objective of this work was to study the effect of soil physicochemical properties on the secondary metabolites of saffron. Our study concerned the analysis of saffron samples by high-performance liquid chromatography-detection by diode array (HPLC-DAD). Soil samples were analyzed by physicochemical methods, ED-XRF fluorescence and X-ray diffraction to determine the different types of clays. Saffron samples grown in loam-clay-sand soils contained high values of crocins and kaempferol 3-sophoroside 7-glucoside but low values of safranal. In addition, saffron samples grown in soils rich in organic matter, phosphorus and potassium contained high values of crocins and kaempferol 3-sophoroside 7-glucoside but low values of safranal. This original approach was carried out for the first time in our study, both by ED-XRF fluorescence and by X-ray diffraction, to determine what elements affect the quality of saffron. Thus, we concluded that clays containing low amounts of iron could have a positive effect on the coloring strength of saffron.

Identification of Compounds of Crocus sativus by GC-MS and HPLC/UV-ESI-MS and Evaluation of Their Antioxidant, Antimicrobial, Anticoagulant, and Antidiabetic Properties.

In order to valorize the species Crocus sativus from Morocco and to prepare new products with high added value that can be used in the food and pharmaceutical industry, our interest was focused on the phytochemical characterization and the biological and pharmacological properties of the stigmas of this plant. For this purpose, the essential oil of this species, extracted by hydrodistillation and then analyzed by GC-MS, revealed a predominance of phorone (12.90%); (R)-(-)-2,2-dimethyl-1,3-dioxolane-4-methanol (11.65%); isopropyl palmitate (9.68%); dihydro-ß-ionone (8.62%); safranal (6.39%); trans-ß-ionone (4.81%); 4-keto-isophorone (4.72%); and 1-eicosanol (4.55%) as the major compounds. The extraction of phenolic compounds was performed by decoction and Soxhlet extraction. The results of the determination of flavonoids, total polyphenols, condensed tannins, and hydrolyzable tannins determined by spectrophotometric methods on aqueous and organic extracts have proved the richness of Crocus sativus in phenolic compounds. Chromatographic analysis by HPLC/UV-ESI-MS of Crocus sativus extracts revealed the presence of crocin, picrocrocin, crocetin, and safranal molecules specific to this species. The study of antioxidant activity by three methods (DPPH, FRAP, and total antioxidant capacity) has proved that C. sativus is a potential source of natural antioxidants. Antimicrobial activity of the aqueous extract (E0) was investigated by microdilution on a microplate. The results have revealed the efficacy of the aqueous extract against Acinetobacter baumannii and Shigella sp. with MIC ≤ 600 µg/mL and against Aspergillus niger, Candida kyfer, and Candida parapsilosis with MIC = 2500 µg/mL. Measurements of pro-thrombin time (PT) and activated partial thromboplastin time (aPTT) in citrated plasma obtained from routine healthy blood donors were used to determine the anticoagulant activity of aqueous extract (E0). The anticoagulant activity of the extract (E0) studied showed that this extract can significantly prolong the partial thromboplastin time (p < 0.001) with a 359 µg/mL concentration. The antihyperglycemic effect of aqueous extract was studied in albino Wistar rats. The aqueous extract (E0) showed strong in vitro inhibitory activity of α-amylase and α-glucosidase compared with acarbose. Thus, it very significantly inhibited postprandial hyperglycemia in albino Wistar rats. According to the demonstrated results, we can affirm the richness of Crocus sativus stigmas in bioactive molecules and its use in traditional medicine.

Fortification and bioaccessibility of saffron apocarotenoids in potato tubers.

Carotenoids are C40 isoprenoids with well-established roles in photosynthesis, pollination, photoprotection, and hormone biosynthesis. The enzymatic or ROS-induced cleavage of carotenoids generates a group of compounds named apocarotenoids, with an increasing interest by virtue of their metabolic, physiological, and ecological activities. Both classes are used industrially in a variety of fields as colorants, supplements, and bio-actives. Crocins and picrocrocin, two saffron apocarotenoids, are examples of high-value pigments utilized in the food, feed, and pharmaceutical industries. In this study, a unique construct was achieved, namely O6, which contains CsCCD2L, UGT74AD1, and UGT709G1 genes responsible for the biosynthesis of saffron apocarotenoids driven by a patatin promoter for the generation of potato tubers producing crocins and picrocrocin. Different tuber potatoes accumulated crocins and picrocrocin ranging from 19.41-360 to 105-800 µg/g DW, respectively, with crocetin, crocin 1 [(crocetin-(ß-D-glucosyl)-ester)] and crocin 2 [(crocetin)-(ß-D-glucosyl)-(ß-D-glucosyl)-ester)] being the main compounds detected. The pattern of carotenoids and apocarotenoids were distinct between wild type and transgenic tubers and were related to changes in the expression of the pathway genes, especially from PSY2, CCD1, and CCD4. In addition, the engineered tubers showed higher antioxidant capacity, up to almost 4-fold more than the wild type, which is a promising sign for the potential health advantages of these lines. In order to better investigate these aspects, different cooking methods were applied, and each process displayed a significant impact on the retention of apocarotenoids. More in detail, the in vitro bioaccessibility of these metabolites was found to be higher in boiled potatoes (97.23%) compared to raw, baked, and fried ones (80.97, 78.96, and 76.18%, respectively). Overall, this work shows that potatoes can be engineered to accumulate saffron apocarotenoids that, when consumed, can potentially offer better health benefits. Moreover, the high bioaccessibility of these compounds revealed that potato is an excellent way to deliver crocins and picrocrocin, while also helping to improve its nutritional value.

Effect of low-pressure cold plasma processing on decontamination and quality attributes of Saffron (Crocus sativus L.).

This study investigated the microbial decontamination of saffron using the low-pressure cold plasma (LPCP) technology. Therefore, other quality characteristics of saffron that create the color, taste, and aroma have also been studied. The highest microbial log reduction was observed at 110 W for 30 min. Total viable count (TVC), coliforms, molds, and yeasts log reduction were equal to 3.52, 4.62, 2.38, and 4.12 log CFU (colony-forming units)/g, respectively. The lowest decimal reduction times (D-values) were observed at 110 W, which were 9.01, 3.29, 4.17, and 8.93 min for TVC, coliforms, molds, and yeasts. LPCP treatment caused a significant increase in the product's color parameters (L*, a*, b*, ΔE, chroma, and hue angle). The results indicated that the LPCP darkened the treated stigma's color. Also, it reduced picrocrocin, safranal, and crocin in treated samples compared to the untreated control sample (p < .05). However, after examining these metabolites and comparing them with saffron-related ISO standards, all treated and control samples were good.