Search Results (30)

Extracting high-molecular-weight (HMW) DNA from cactus tissues remains technically challenging due to the abundance of mucilage, pectins, polyphenols, and other metabolites that compromise DNA purity, increase viscosity, and reduce integrity, thereby limiting its suitability for long-read sequencing. This constraint is particularly relevant in Selenicereus megalanthus, a crop of increasing agronomic and genomic importance for which optimized protocols for third-generation sequencing remain limited. Here, we compared four CTAB-based DNA extraction protocols using dehydrated cladode tissue and evaluated DNA quality using NanoDrop spectrophotometry, Qubit fluorometry, agarose gel electrophoresis, and functional validation via sequencing on the Oxford Nanopore PromethION 2 Solo platform. Among the tested methods, our proposed optimized mucilage-adapted CTAB (MuCTAB) protocol, comprising 4% CTAB, 4% PVP-40, 0.5% β-mercaptoethanol, and proteinase K, showed the best overall performance. MuCTAB yielded the highest dsDNA concentration (239.63 ± 34.37 ng/µL), optimal purity ratios (A260/A280 = 1.96 ± 0.05; A260/A230 = 2.01 ± 0.01), and superior DNA integrity. Nanopore validation confirmed its effectiveness, with MuCTAB producing the highest sequencing yield (84.2 Gbp), read count, mean read quality score (Q18.4), read N50 (40.3 kbp), and maximum read length (1.9 Mbp). Overall, MuCTAB represents a low-cost, reproducible, and efficient method for HMW DNA extraction from mucilage-rich pitahaya tissues and shows promising potential for adaptation to other recalcitrant plant species. Full article

The main causes of lemon fruit senescence and deterioration are fungal diseases and postharvest quality loss. Edible coatings have been proposed to delay quality loss in fresh produce by reducing moisture loss and helping preserve external appearance. Natural functional coatings are increasingly being investigated as potential alternatives to synthetic waxes and preservatives due to environmental and consumer safety concerns. The effect of a natural edible coating based on Opuntia ficus-indica mucilage on extending the shelf-life of lemons during cold storage was investigated. Lemon fruits were treated with the mucilage-based edible coating and subsequently stored under controlled cold conditions. Coated and uncoated lemon fruits were evaluated for their physicochemical properties, including weight loss, total soluble solids, pH, titratable acidity, color, and microbiological analysis, as well as total polyphenol content and antioxidant activity, over a 60-day storage period at 5 ± 0.5 °C and 95% relative humidity. The results showed that the mucilage-based coating improved lemon fruit storage performance, effectively preserving key physicochemical and microbiological parameters over 60 days of cold storage (p ≤ 0.05). In particular, the treatment maintained fruit firmness, reduced weight loss (up to 45%), increased juice content (up to 1.8-fold), and delayed microbial decay compared to control samples. Coated fruits also exhibited higher total polyphenolic content and antioxidant activity than control samples at the end of storage. In addition, using mucilage extracted from cactus pear cladode waste provides a sustainable way to add value to the product, with promising industrial applications as an alternative to synthetic fruit coatings. Full article

Growing concern about the environmental impact of traditional packaging has driven the development of biodegradable edible films made from natural and functional biopolymers. Various by-products generated during harvesting can be subjected to valorization. Potato, a tuber with high starch content, and carrot, rich in β-carotene, represent important sources of polymeric matrix and bioactive compounds, respectively. Similarly, the use of biodegradable plasticizers such as pectin and polysaccharides derived from nopal mucilage is a viable alternative. This study assessed the physical and chemical properties of edible films composed of potato starch (PS), cactus mucilage (NM), carrot extract (CJ), citrus pectin (P), and glycerin (G). The films were produced by means of casting, with three mixtures prepared that had different proportions of CJ, P, and PS. The experiments were adjusted to a simple mixture design, and the data were analyzed in triplicate, using Pareto and Tukey diagrams at 5% significance. Results showed that adding CJ (between 5 to 6%), P (between 42 to 44%) and PS (between 43 to 45%) significantly affects all of the evaluated physical and chemical properties, resulting in films with luminosity values greater than 88.65, opacity ranging from 0.20 to 0.54 abs/mm, β-carotene content up to 26.11 μg/100 g, acidity between 0.22 and 0.31% and high solubility with a significant difference between treatments (p-value < 0.05) and low water activity (around of 0.47) (p-value > 0.05). These characteristics provide tensile strength up to 5.7 MPa and a suitable permeability of 1.6 × 10⁻² g·mm/h·m²·Pa (p-value < 0.05), which ensures low diffusivity through the film. Similarly, increasing the CJ addition enables the functional groups of the other components to interact. Using carrot extract and potato starch is a promising approach for producing edible films with good functional qualities but with high permeability. Full article

This review presents a bibliometric analysis of the research landscape on cactus mucilage and its application in biodegradable films for food packaging. The objective was to identify scientific trends, key contributors, and emerging research areas from 2012 to 2022. Original scientific and review articles were retrieved from the Web of Science database and analyzed using VOSviewer software to map co-authorship, keyword co-occurrence, and country collaboration networks. The analysis revealed that Tunisia, the United States, Germany, and Luxembourg, along with their research institutions, are among the most productive contributors in this field. The study also identified leading authors and journals that focus on the development of cactus-based biodegradable films. Common research topics included extraction methods, film formulation, and evaluations of physical, chemical, and functional properties relevant to food packaging. The results emphasize the growing scientific interest in cactus mucilage as a renewable and sustainable alternative to synthetic polymers. This review provides insights into the current state of the field and highlights opportunities for innovation and collaboration in the development of environmentally friendly food packaging technologies. Full article

Nopal cladode mucilage is a product of great importance in fodder, agri-food, industry, and health areas. This study aimed to evaluate the effect of three soil moisture contents on some physiological and chemical variables associated with the mucilage yield and quality of three morphotypes of fodder nopal (Opuntia spp.). A randomized block experimental design in a split–split plot arrangement with three replicates was used. The large plots represented the following soil moisture contents (SMC): optimum soil moisture content (OSMC) from 22 to 27%; suboptimum soil moisture content (SSMC) from 16 to 21%; and deficient soil moisture content (DSMC) from 10 to 15%. The subplots consisted of three cactus pear genotypes identified by the following IDs: C-CH, -C-NA, and C-HE. The relative water content (RWC) was significantly higher in the C-HE morphotype across each soil moisture content, and the lowest value was recorded in C-NA with OSMC; -C-CH had the lowest values in SSMC and DSMC, with 71.3% and 44.3%, respectively. There were slight variations in chlorophyll with SSMC; the C-NA and C-CH morphotypes had significantly higher chlorophyll contents, with values of 10.3 mg g⁻¹ 100 FW of chlorophyll a. and 5.87 mg 100 g⁻¹ FW of chlorophyll b. The C-CH morphotype had the best mucilage yield, with 800 mL kg⁻¹ FW and 712.6 mL kg⁻¹ FW in OSMC and SSMC, respectively; DSMC showed the lowest yield at 552.3 mL kg⁻¹ FW. The quality of cladode mucilage by treatment did not vary by soil moisture content or among nopal morphotypes. Additionally, there was a positive correlation among the relative water content and the chlorophyll a, b, and total chlorophyll contents with the yield of the nopal cladode mucilage, but not with the ash content or total solids as variables of mucilage quality vs. yield. Full article

The accelerated ripening and senescence of fruits and vegetables is characterized by various biochemical changes that hinder the maintenance of their postharvest quality. In this context, developing edible films and coatings formulated with natural and biodegradable materials emerges as a sustainable strategy for preserving the quality parameters of these products in replacement of conventional petroleum-based packaging. Recently, plant-based polymers, including mucilage from different cactus species and/or their bioactive compounds, have been investigated to develop edible films and coatings. As the available literature indicates, the Opuntia genus stands out as the most used for mucilage extraction, with the cladode being the most exploited part of the plant. Conventional extraction methods are widely employed to obtain mucilages, which are applied to fruits and vegetables after being combined with plasticizing and cross-linking agents. In general, these films and coatings have proven effective in prolonging the shelf life and maintaining the nutritional, physical, and sensory quality of fruits and vegetables. Given their preservation potential, combining cactus mucilages with bioactive compounds, probiotics, and prebiotics represents an emerging trend in developing functional films and coatings. However, some limitations have been identified, such as the underutilization of different species and parts of the plant, the lack of standardization in extraction methods, and the absence of studies on the effects of the physicochemical properties of mucilages in the formulation and characteristics of films and coatings. Therefore, overcoming these limitations is essential for developing edible films and coatings with enhanced techno-functional properties and greater commercial viability. Full article

The art of dyeing fabrics is one of the oldest human activities. In order to improve the fastness properties of dyeing products, various additives are added to optimize the uniformity of fibers and surfaces and improve dye distribution. Unfortunately, these additives can be harmful and very often are not biodegradable. This article reports on the possibility of using a natural additive for dyeing textiles: a polysaccharide extracted from the prickly pear cactus (Opuntia ficus indica). One type of fabric was tested, silk, with different colors. Several samples were prepared and dyed for each color, adding the same additives but also a commercial chemical aid for one of them and the mucilage of Opuntia for another. The fastness of the applied dyes was evaluated by washing at different temperatures with a common liquid detergent. All samples were analyzed before and after washing with a colorimeter to evaluate the color changes. The results of the analyses reported and compared indicate the potential of prickly pear mucilage as an additive for dyeing silk, which is easily accessible, safe, and sustainable compared to other commonly used additives. Full article

The investigation of novel, natural polymers has gained considerably more exposure for their desirable, often specific, functional properties. Multiple researchers have explored these biopolymers to determine their potential to address many food processing, packaging and environmental concerns. Mucilage from the cactus pear (Opuntia ficus-indica) is one such biopolymer that has been identified as possessing a functional potential that can be used in an attempt to enhance food properties and reduce the usage of non-biodegradable, petroleum-based packaging in the food industry. However, variations in the structural composition of mucilage and the different extraction methods that have been reported by researchers have considerably impacted mucilage’s functional potential. Although not comparable, these factors have been investigated, with a specific focus on mucilage applications. The natural ability of mucilage to bind water, alter the rheology of a food system and develop biofilms are considered the major applications of mucilage’s functional properties. Due to the variations that have been reported in mucilage’s chemical composition, specifically concerning the proportions of uronic acids, mucilage’s rheological and biofilm properties are influenced differently by changes in pH and a cross-linker. Exploring the factors influencing mucilage’s chemical composition, while co-currently discussing mucilage functional applications, will prove valuable when evaluating mucilage’s potential to be considered for future commercial applications. This review article, therefore, discusses and highlights the key factors responsible for mucilage’s specific functional potential, while exploring important potential food processing and packaging applications. Full article

Loquat (Eriobotrya japonica Lindl.), a non-climacteric fruit, is susceptible to physical and mechanical damage, as well as decay, especially after minimal processing, resulting in a short postharvest lifespan The objective of our study was to evaluate the impact of a cactus pear (OFI) mucilage-based edible coating enriched with glycerol and l-glutamine on the quality and nutraceutical value of minimally processed white-flesh Martorana loquat fruits during cold storage. After washing and processing the cladodes, mucilage was extracted, and two different coatings (EC1: 60% OFI mucilage, 40% glycerol; EC2: 67% OFI mucilage, 30% glycerol, 3% glutamine) were formulated and compared with an untreated sample (CTR). Our analyses covered various parameters, including color, total soluble solid content, titratable acidity, antioxidant activity, and total phenols. Additionally, sensory analysis was conducted and visual scores were obtained. The results suggest that the application of a cactus pear mucilage-based edible coating, supplemented with glycerol and L-glutamine, effectively preserves the quality attributes of minimally processed loquat fruits. Full article

Recent green manufacturing demands have boosted the development of new biodegradable lubricants to replace petroleum-based lubricants. In this regard, water-based lubricants have been at the vanguard of recent research for a wide range of industrial applications, including metalworking fluids (MWFs). In this work, we present an experimental investigation on the performance of novel green MWFs based on aqueous nopal mucilage solutions. For this, fully biodegradable solutions with different mucilage concentrations (2.29, 4.58, and 6.85 mg/mL) were evaluated in terms of rheological, tribological, thermal stability, and turning (minimum quantity lubrication) performance and compared to a commercial semisynthetic oil-based MWF (Cimstar 60). Mucilage solutions exhibited viscoelastic shear-thinning behavior, which was enhanced along with mucilage concentration. The solution with the highest mucilage content studied resulted in the lowest wear, friction, and temperature in comparison to the other solutions and neat water in extreme pressure four-ball tests and a similar level of lubricity as compared to the commercial MWF in cutting tests. This performance is associated with the enhanced viscosity and elasticity of the solution, as well as the contents of lipids with fatty acids in the mucilage. Overall, the present results reveal the relevance of the viscoelastic behavior of the lubricant, elasticity in particular, in lubrication processes and point to nopal mucilage as an effective green additive to produce innocuous MWFs. Full article

Pectin and alginate are well-established biopolymers used in natural film development. Single-polymer mucilage films were developed from freeze-dried native mucilage powder of two cultivars, ‘Algerian’ and ‘Morado’, and the films’ mechanical properties were compared to single-polymer pectin and alginate films developed from commercially available pectin and alginate powders. The casting method prepared films forming solutions at 2.5%, 5%, and 7.5% (w/w) for each polymer. Considerable variations were observed in the films’ strength and elasticity between the various films at different polymer concentrations. Although mucilage films could be produced at 5% (w/w), both cultivars could not produce films with a tensile strength (TS) greater than 1 MPa. Mucilage films, however, displayed > 20% elongation at break (%E) values, being noticeably more elastic than the pectin and alginate films. The mechanical properties of the various films were further modified by varying the pH of the film-forming solution. The various films showed increased TS and puncture force (PF) values, although these increases were more noticeable for pectin and alginate than mucilage films. Although single-polymer mucilage films exhibit the potential to be used in developing natural packaging, pectin and alginate films possess more suitable mechanical attributes. Full article

Pectin and alginate satisfy multiple functional requirements in the food industry, especially relating to natural packaging formulation. The continuous need for economic and environmental benefits has promoted sourcing and investigating alternative biomaterials, such as cactus pear mucilage from the cladodes of Opuntia spp., as natural packaging alternatives. The structural and mechanical properties of mucilage, pectin and alginate films developed at a 5% (w/w) concentration were modified by treating the films with calcium (Ca) in the calcium chloride (CaCl₂) form. Scanning electron microscopy (SEM) showed the 5% (w/w) ‘Algerian’ and ‘Morado’ films to display considerable microstructure variation compared to the 5% (w/w) pectin and alginate films, with calcium treatment of the films influencing homogeneity and film orientation. Treating the alginate films with a 10% (w/w) stock CaCl₂ solution significantly increased (p < 0.05) the alginate films’ tensile strength (TS) and puncture force (PF) values. Consequently, the alginate films reported significantly higher (p < 0.05) film strength (TS and PF) than the pectin + Ca and mucilage + Ca films. The mucilage film’s elasticity was negatively influenced by CaCl₂, while the pectin and alginate films’ elasticity was positively influenced by calcium treatment. These results suggest that the overall decreased calcium sensitivity and poor mechanical strength displayed by ‘the Algerian’ and ‘Morado’ films would not make them viable replacements for the commercial pectin and alginate films unless alternative applications were found. Full article

Although the benefits of polymeric blend films have been well-established, mucilages’ interaction with other commercial bio-based polymers remains greatly unknown. Pectin and alginate were used to develop such polymeric blend films, with the addition of both ‘Algerian’ and ‘Morado’ cultivar freeze-dried, native mucilage precipitate. Mucilage additions at 0.25% and 1% (w/w), together with glycerol at 60% (w/w), influenced the mechanical properties of the 5% (w/w) pectin–mucilage and 5% (w/w) alginate–mucilage blend films differently. ‘Morado’ mucilage positively influenced the pectin film tensile strength (TS) and puncture force (PF) measurements, increasing the overall film strength compared to the homopolymeric pectin films. Calcium chloride (CaCl₂) treatment and increasing mucilage concentration further enhanced the composite pectin–mucilage film strength. Contrasting results were obtained for alginate blend films compared to those of pectin. Studying the scanning electron microscope (SEM) images of the microstructures of CaCl₂-treated pectin–mucilage and alginate–mucilage films confirmed superior microstructural film networks for pectin–mucilage films, which resulted in enhanced film strength, where the lack of polymer compatibility, as seen with alginate–mucilage, resulted in decreased film strength. These results indicate that native mucilage should be considered when developing such blend polymeric films, as it has the potential to enhance the films’ strength and elasticity. Full article

This article presents results on the use of a new material as a solidifying agent and/or color-fixing agent. A special polysaccharide material extracted from the prickly pear cactus (Opuntia ficus indica) was tested on historical materials and modern papers. An old book from the 18th century was chosen as historical material. From the mentioned book 42 pages were taken, on which a conservation and restoration pretreatment was performed before applying the polysaccharide material: sampling, fiber analysis, dry cleaning, ink solubility, pH test, thickness measurement and wet cleaning. The paper sheets provided for the test were divided into 4 groups, 3 of which were treated with gel and one left untreated as a reference. The division into groups is not only due to the different method of application, but also due to the process of gel extraction. The effect of the treatment was analyzed using FTIR-ATR. To test the mucilage as color-fixing agent 2 samples were prepared using watercolor papers colored with 6 different watercolors applied to 2.5 cm² samples for each color in two rows of different intensity. One of the 2 samples was treated with gel, but both were immersed for 3 times in a water-ethanol solution for approximately 20 min as is standard practice in conservation and restoration. After washing, both specimens were subjected to colorimetric analysis to assess their differences. The results provided satisfactory evidence for the protection of paints sensitive to aqueous treatments and suggest the use of mucilage as a new material in cleaning method for water-soluble media. Full article

Opuntia joconostle is a semi-wild cactus cultivated for its fruit. However, the cladodes are often discarded, wasting the potentially useful mucilage in them. The mucilage is composed primarily of heteropolysaccharides, characterized by their molar mass distribution, monosaccharide composition, structural features (by vibrational spectroscopy, FT IR, and atomic force microscopy, AFM), and fermentability by known saccharolytic commensal members of the gut microbiota. After fractionation with ion exchange chromatography, four polysaccharides were found: one neutral (composed mainly of galactose, arabinose, and xylose) and three acidic, with a galacturonic acid content from 10 to 35%_mol. Their average molar masses ranged from 1.8 × 10⁵ to 2.8 × 10⁵ g·mol⁻¹. Distinct structural features such as galactan, arabinan, xylan, and galacturonan motifs were present in the FT IR spectra. The intra- and intermolecular interactions of the polysaccharides, and their effect on the aggregation behavior, were shown by AFM. The composition and structural features of these polysaccharides were reflected in their prebiotic potential. Lactobacilli and Bifidobacteria were not able to utilize them, whereas members of Bacteroidetes showed utilization capacity. The obtained data suggest a high economic potential for this Opuntia species, with potential uses such as animal feed in arid areas, precise prebiotic, and symbiotic formulations, or as the carbon skeleton source in a green refinery. Our methodology can be used to evaluate the saccharides as the phenotype of interest, helping to guide the breeding strategy. Full article