Search Results (22)

This study investigates the phytochemical profile, antioxidant capacity, and antimicrobial potential of Crocus sativus L. (saffron) tepal extracts obtained via different solvent systems. Here, a biochemical screening was performed using spectrophotometry and HPLC-DAD, while molecular docking simulations were carried out to evaluate the possible interactions between saffron tepal metabolites and bacterial target proteins. In parallel, antioxidant activity was assessed using radical scavenging assays, whereas antimicrobial potential (i.e., MIC, MBC, and MFC) was tested against selected bacterial strains. Results indicated that aqueous successive and crude extracts yielded the highest concentrations of polyphenols, flavonoids, and condensed tannins. In detail, HPLC-DAD analysis specifically identified significant levels of gallic acid, epicatechin, and various anthocyanins. These extracts demonstrated robust antioxidant and antimicrobial activities. This latter evidence was corroborated by the docking analyses, which revealed that chlorogenic acid and petunidin-3-glucoside exhibited high binding affinities for 2NRK and 2NZF, whereas epicatechin and pelargonidin effectively targeted 8ACR. These findings underscore the therapeutic potential of C. sativus tepals as natural bioactive agents, suggesting a promising role in overcoming antibiotic resistance and supporting their development for pharmaceutical applications. Full article

Medicinal and Aromatic Plant (MAP) by-products constitute a vast reservoir of bioactive metabolites with antioxidant and antimicrobial properties, offering potential for the development of high added value natural products. This study focuses on the by-product (tepals) remaining during the process of receiving the stigma of Crocus sativus L. Iridaceae (saffron), which is the commercially exploitable part of the flowers. The tepals are the main part of the flowers (>95%) and are still discarded in the fields during the collection of the stigmas in Kozani, Greece. According to numerous findings, the saffron tepals are rich in flavonoids with notable biological properties, and our aim was to investigate an alternative for their management. Within this context, dry and frozen tepals were extracted at a laboratory scale through microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE), followed by adsorption resin technology (ART) for the preparation of enriched extracts. Furthermore, their HPTLC profiling, the phenolic (TPC) and flavonoid (TFC) content, and the free-radical-scavenging (DPPH) and anti-tyrosinase activity were evaluated. The frozen tepals were further extracted at a pilot scale using MAE and maceration (Mc) techniques, followed by ART treatment to remove the contained sugars. The enriched extract produced at a pilot scale using MAE and ART sequentially is characterized by a high phenolic (147.2 mg GAE/g dry extract) and flavonoid (114.8 mg QUE/g dry extract) load. These findings demonstrate that saffron tepals, traditionally considered waste, can serve as a valuable raw material for producing extracts rich in phenolic derivatives, particularly flavonoids and anthocyanins. Full article

Saffron (Crocus sativus L.), a perennial plant of the Iridaceae family, which is also known as “red gold”, is one of the most expensive spices throughout the world. Originally, it was mainly used as a condiment and natural dye for food, and as a medicinal plant in folk medicine. Its cultivation is characterized by an extensive use of labor, since most of the crop management techniques (e.g., sowing, weeding, flower picking, and stigma separation) are performed manually. The aim of this work is to investigate how the adoption of sustainable cultivation techniques could improve the profitability of saffron at the primary level. Thus, economic and technical data were collected directly on a farm in a marginal area in Northwestern Italy, in order to compare the productivity and profitability of traditional and innovative cultivation techniques. The effect of sustainable practices, such as the use of beneficial microorganisms, that is, arbuscular mycorrhizal fungi (AMF), on the productivity of saffron was considered. In a previous work, AMF inoculation with Rhizophagus intraradices and Funneliformis mosseae led to an increase in the flower and saffron spice yields, compared to uninoculated controls. The profitability of the saffron (including tepals, its by-product) considered in our case study, expressed as economic profit (pure profit), was found to be slightly negative for the traditional cultivation method (without the use of AMF) and also, albeit to a lesser extent, for the innovative technology (with the use of AMF). This slightly negative result is mainly due to the implicit cost of family labor for both the traditional and innovative cultivation techniques. The results of our study can be considered a further step in favor of the use of cultivation techniques that improve crop productivity and, at the same time, are sustainable. They also support the spread of minor crops, which, nevertheless, are important to maintain agricultural activities in marginal territories. Full article

Saffron, branded as Repron^®, is effective in slowing the progression of several neurodegenerative diseases. Its production, however, requires specific cultivation techniques and procedures that, together with low yields, make it expensive. To address this challenge, hydroponic cultivation has been adopted. Previous studies have shown that hydroponically cultivated saffron and Repron^® share comparable chemical compositions and neuroprotective effects under oxidative stress conditions. In this study, we evaluated the protective properties of extracts derived from Crocus sativus L. waste, compared with those of saffron derived from stigmas. Human retinal pigment epithelium (ARPE-19) cells were pre-treated with extracts of various plant waste fractions before being subjected to three stress conditions: H₂O₂-induced oxidative stress (500 μM, 3 h), lipopolysaccharide (LPS; 0.25 mg/mL, 24 h), and hyperglycemia (25 mM glucose, 96 h). Saffron Repron^® served as a positive control. The results revealed that the extract derived from C. sativus waste had superior protective effects against oxidative stress and inflammation by preserving the state of the mitochondria and tight junctions (ZO-1); conversely, the tepal extract alone was more effective under hyperglycemic conditions by also modulating acrolein levels. These results suggest that different plant fractions contain bioactive compounds with specific protective actions, which together lead to increased cell survival. Full article

Saffron spice is obtained from the flower’s stigmas through a labor-intensive process. However, other organs (particularly the leaves and tepals) are often regarded as waste. To investigate the health benefits of saffron leaf by-products, an optimized methodology was developed to obtain a phenol-enriched fraction. The main components of this fraction were identified by HPLC-DAD/ESI-MS and the antiproliferative and metal-chelating effects on colon cancer cells (Caco-2) and Fe²⁺ and Cu²⁺ ions, respectively, were evaluated. The process involved the extraction of saffron leaves with a 70% hydroalcoholic solution, followed by purification using liquid chromatography. Chemical characterization revealed the presence of several phenolic compounds, including flavonoids (kaempferol, luteolin and quercetin glycosides) as major constituents; whereas, in vitro assays revealed a strong dose-dependent inhibition of cell proliferation. Likewise, the sample exhibited significant iron- and copper-chelating activity, suggesting its potential as a natural chelator to help mitigate the carcinogenic effects of metal accumulation in humans. In summary, this study underscores the potential of the saffron leaf fraction as a promising natural and complementary chemoprotective agent in colorectal cancer. Additionally, these results underscore the value of agricultural by-products, supporting a circular bioeconomy by reducing environmental impact and promoting the sustainable use of natural resources. Full article

Tepals of the Crocus sativus flower constitute the most abundant floral residue during saffron production (350 kg tepals/kg stigmas). Being a natural source of polyphenols with antioxidant properties, they can be reused to create potentially valuable products for pharmaceutical applications, generating a new income source while reducing agricultural bio-waste. In this work, composite hydrogels based on blends of pectin and gellan gum containing Crocus sativus tepal extract (CSE) have been proposed for the regeneration and healing of cutaneous wounds, exploiting the antioxidant properties of CSE. Various physico-chemical and mechanical characterizations were performed. The skin permeation of CSE was investigated using Franz cell diffusion system. The composite films were cytocompatible and able to counteract the increase in ROS, restore the production of matrix proteins, and favor wound closure. To conclude, CSE-loaded composite films represent a promising strategy to promote the body’s natural healing process. In addition, by reusing saffron tepals, not only can we develop new, sustainable treatments for skin diseases, but we can also reduce agricultural waste. Full article

Plant exosomes exhibit high stability and easy absorption, and have emerged as promising bioactive tools due to their potential health benefits and biomedical applications. Saffron tepals contain abundant metabolites with potential therapeutic properties and were used for exosome extraction by ultracentrifugation and gradient purification. The exosomes showed an average particle size of 151.5 ± 79.6 nm and exhibited a spherical morphology. Five well-conserved miRNAs—miR157, miR166, miR168, miR396, and miR398—were identified in the exosomes, which are involved in the coordination of growth and physiological plant responses with endogenous and environmental abiotic and biotic signals, and their potential targets in mammals are upregulated in specific cancer types and associated with inflammation. Proteome analysis revealed an enrichment of proteasome proteins, ribosomal proteins, and proteins involved in the cytoskeleton, transport across the membrane (ABC transporters), and vesicle trafficking (RAB GTPases, TM9SF and Coatomer subunits). Metabolite analyses showed mainly anthocyanins. The exosomes have selective stimulatory activity on macrophages, increasing the expression of surface molecules (CD80 and CD86), and cytokines (IL-1β, IL-6, and TNF-α), but not the levels of IL-10. Overall, these results indicated that saffron flowers are an effective and abundant source of exosomes as new nanomedicines for human health. Full article

Repurposing saffron (Crocus sativus) waste presents a sustainable strategy for generating high-value products within the bioeconomy framework. Typically, flower components are discarded after stigma harvest, resulting in significant waste—350 kg of tepals per kilogram of stigmas. This research employed a comprehensive approach, integrating bioactivity studies (in vitro and in silico) with Life Cycle Assessment (LCA) evaluations, to extract and assess bioactive compounds from C. sativus tepals sourced in Tuscany, Italy. Phytochemical characterization using UPLC-MS/MS revealed a high abundance and variety of flavonoids in the hydro-ethanolic extract (CST). The antioxidant capacity was validated through various assays, and the ability to mitigate H₂O₂-induced oxidative stress and enhance fermentation was demonstrated in Saccharomyces cerevisiae. This study reports that C. sativus tepals extract reduces oxidative stress and boosts ethanol fermentation in yeast, paving the way for applications in the food and biofuels sectors. Further validation in RAW 264.7 macrophages confirmed CST’s significant anti-inflammatory effects, indicating its potential for pharmaceutical, cosmeceutical, and nutraceutical applications. In silico studies identified potential targets involved in antioxidant and anti-inflammatory processes, shedding light on possible interaction mechanisms with Kaempferol 3-O-sophoroside (KOS-3), the predominant compound in the extract. The integration of LCA studies highlighted the environmental benefits of this approach. Overall, this research underscores the value of using waste-derived extracts through “green” methodologies, offering a model that may provide significant advantages for further evaluations compared to traditional methodologies and supporting the circular bioeconomy. Full article

The cultivation of Crocus sativus L. to obtain the saffron spice generates a large amount of biowaste, constituted mainly by the flower’s tepals. The aim of this work was to evaluate the antioxidant and dermo-protective effect of a complex methanolic extract of C. sativus tepals. The extract’s major phenolic content was analyzed using ultra-high performance liquid chromatography with electrospray ionization, coupled with quadrupole-time-of-flight-mass spectrometry (UHPLC-ESI-QTOF-MS). Then, the antioxidant in vitro activity of the extract was studied and related to their chemical composition. Likewise, the effect on intracellular ROS levels in HepG2 and Hs27 cell culture was determined in normal culture and under hydrogen-peroxide-induced oxidative stress. Finally, tyrosinase, hyaluronidase, collagenase, elastase, and xanthine oxidase assays were carried out to determine the dermo-protective capacity of the extract. The high polyphenol content, including flavonoids and anthocyanins, explains the antioxidant effect of the extract both in vitro and in culture assays. The extract has a significant and remarkable protective capacity against oxidative stress induced in culture of the two studied cell lines. It is also remarkable in its ability to inhibit hyaluronidase, tyrosinase, and xanthine oxidase. Results pointed out this biowaste extract as a promising ingredient in the composition of cosmetics. Full article

Crocus sativus L. is largely cultivated because it is the source of saffron, a well-appreciated and valued spice, not only for its culinary use but also because of its significant biological activities. Stigmas are the main product obtained from flowers, but in addition, tepals, largely considered a waste product, represent a big source of flavonoids and anthocyanins. This study aimed to delve into the phytochemical composition of saffron tepals and investigate whether the composition was influenced by the extraction technique while investigating the main analytical techniques most suitable for the characterization of tepal extracts. The research focuses on flavonoids, a class of secondary metabolites, and their health benefits, including antioxidant, anti-inflammatory, and anticancer properties. Flavonoids occur as aglycones and glycosides and are classified into various classes, such as flavones, flavonols, and flavanones. The most abundant flavonoids in tepals are kaempferol glycosides, followed by quercetin and isorhamnetin glycosides. Overall, this review provides valuable insights into the potential uses of tepals as a source of bioactive compounds and their applications in various fields, promoting a circular and sustainable economy in saffron cultivation and processing. Full article

Saffron (Crocus sativus L.) is a traditional Mediterranean plant whose stigmas are used to obtain the most expensive spice in the world. Nevertheless, there is a lack of sustainability in its production, since, to produce 1 kg of saffron, about 350 kg of tepals are discarded. Therefore, this study aimed to develop wheat and spelt breads enriched with saffron floral by-products at a ratio of 0, 2.5, 5, and 10% (w/w), respectively, and to evaluate their nutritional, physicochemical, functional, and sensory properties, as well as the stability of antioxidant compounds during the in vitro digestion. The results revealed that the addition of saffron floral by-products, especially at 10%, increased the dietary fiber content by 25–30% of traditional wheat and spelt breads; improved their mineral content (270–290 mg/100 g for K, 90–95 mg/100 g for Ca, 40–50 mg/100 g for Mg, and 15–18 mg/100 g for Fe); changed their textural properties; and significantly enhanced the phenolic content and antioxidant ability (at 5 and 10%), which remained stable throughout the in vitro oral and gastrointestinal digestion processes. From a sensory point of view, the addition of saffron flowers modified the organoleptic properties of breads. Thus, these novel vegan enriched breads could exert beneficial effects on human health after their intake, making saffron floral by-products suitable and sustainable ingredients to develop new functional foods such as healthier alternative vegan bakery products. Full article

Post-prandial hyperglycemia typical of diabetes mellitus could be alleviated using plant-derived compounds such as polyphenols, which could influence the activities of enzymes involved in carbohydrate digestion and of intestinal glucose transporters. Here, we report on the potential anti-hyperglycemic effect of Crocus sativus tepals compared to stigmas, within the framework of valorizing these by-products of the saffron industry, since the anti-diabetic properties of saffron are well-known, but not those of its tepals. In vitro assays showed that tepal extracts (TE) had a greater inhibitory action than stigma extracts (SE) on α-amylase activity (IC50: TE = 0.60 ± 0.09 mg/mL; SE = 1.10 ± 0.08 mg/mL; acarbose = 0.051 ± 0.07) and on glucose absorption in Caco-2 differentiated cells (TE = 1.20 ± 0.02 mg/mL; SE = 2.30 ± 0.02 mg/mL; phlorizin = 0.23 ± 0.01). Virtual screening performed with principal compounds from stigma and tepals of C. sativus and human pancreatic α-amylase, glucose transporter 2 (GLUT2) and sodium glucose co-transporter-1 (SGLT1) were validated via molecular docking, e.g., for human pancreatic α-amylase, epicatechin 3-o-gallate and catechin-3-o-gallate were the best scored ligands from tepals (−9.5 kcal/mol and −9.4 kcal/mol, respectively), while sesamin and episesamin were the best scored ones from stigmas (−10.1 kcal/mol). Overall, the results point to the potential of C. sativus tepal extracts in the prevention/management of diabetes, likely due to the rich pool of phytocompounds characterized using high-resolution mass spectrometry, some of which are capable of binding and interacting with proteins involved in starch digestion and intestinal glucose transport. Full article

Saffron spices are composed of dehydrated stigmas of Crocus sativus L. A large amount of bio-residues (stamens, tepals, and stigmas) is generated during the production of this spice (~92 g of bio-residues per 100 g of flowers). These bio-residues are usually discarded losing the chance to obtain interesting bioactive compounds from them. In this work, we use the saffron bio-residues as possible source of natural bioactive compounds. Different extraction conditions were applied obtaining hydrophilic and lipophilic components. The antioxidant activity of the bioactive compounds in the different conditions were analysed using the ABTS method developed by our team. Furthermore, the total content of phenolic compounds and flavonoids present in the bio-residues were estimated. We demonstrated that bio-residues contain a high amount of both phenolic and flavonoid compounds with a strong antioxidant potential effect. Moreover, we compared the antioxidant activities of saffron bio-residues (obtained from stamens, tepals, and stigmas). The extraction was made at two different pH (4.5 and 7.5) and measured (antioxidant activity, flavonoid and phenol content) at pH 7.5. Another extraction done at pH 7.5 measured antioxidant activity, flavonoid and phenol content at time 0 (t = 0 h) and after 24 h (t = 24 h) at pH 4.5 and 7.5. We point out that bioresidues contain antioxidant activity (up to 8.42 µmoles Trolox/100 g DW), total phenols (up to 111.91 µmoles EG/100 g DW) and total flavonoids (up to 109.25 µmoles QE/100 g DW) as bioactive compounds. The applicability of bio-residues as additives is promising, both in the pharmaceutical and in the food industry as nutraceuticals and phytogenics. The variability in pH and the colour originating from it must be taken into account. Full article

Saffron (Crocus sativus L.) cultivation is widespread in different parts of the world, including various Mediterranean areas. The crop management techniques, requiring intensive manual labor from planting, weeding, flower picking to the collecting of stigmas, contribute greatly to the high price of the spice. Traditionally, the corms are cultivated in field soil and only stigmas are collected to obtain the spice while the flower’s remaining parts, corresponding to about 90% of the total biomass, are discarded and thrown away. In this study, in order to overcome some difficulties occurring during the whole crop cycle (pathogens, fungi, pests, weeds, etc.), as well as to ease and increase floral bioresidue recovery, an alternative planting way for Crocus sativus L. was proposed relying on the use of large pots. For this aim, corms with 3.0–3.5 cm diameter size, from two different geographical origins (Spain, Holland), were planted in plastic pots with a volume of 250 L or 350 L, placed in two different areas of the Basilicata region (Italy). The effect of this new growing condition on dry stigma yield as well as daughter corm yield and size was evaluated. Although this cultivation system is more expensive than the traditional one, it offers numerous and huge advantages. Among them, it allows us to maintain a more correct posture and to preserve flower integrity during harvesting. The structural integrity of the tepals is a very important factor to obtain innovative dried flowers in their original tridimensional shape (3D). Consequently, the proposed cultivation system facilitates the achievement of a real “niche product” with high added value (absence of pollen grains). Moreover, the qualitative analysis of the spice, performed according to the International Standardization Organization Normative 3632 (ISO 3632-2/1:2010/2011), classified all investigated saffron samples in the first qualitative category. The results of the first three trial years are very exciting and promising as they are similar to those from the literature carried out in ground soil. However, corms from Spain gave the best results. Further investigations are in progress in order to optimize this alternative cultivation system. Full article

The current production system of saffron spice generates hundreds of tons of waste. Thus, the aim of this study was to value both saffron and its floral by-products as a source of natural bioactive extracts, studying the in vitro antioxidant capacity, the composition of the volatile fraction by GC-MS/MS, and the determination of crocetins esters by HPLC-PDA. Saffron stigmas and floral by-products showed a high content of polyphenols and different antioxidant properties. Floral bio-residues (tepals, stamens, and styles) presented a high concentration of anthocyanins, and stigmas had high levels of flavonoids, β-carotene, and total crocins. In stigmas, 25 different volatile components were found, with safranal the most relevant. Floral by-products volatile composition consisted of 55 compounds with varying amounts depending on the drying treatment; all the samples presented acetic acid, 2(5H)-furanone, and phenylethyl alcohol. Therefore, saffron stigmas and flower by-products represent a sustainable source of bioactive ingredients for innovative healthy food formulations. Full article