Enzyme-assisted extraction of cactus bioactive molecules under high hydrostatic pressure

BACKGROUND

To improve the extraction and recovery of bioactive materials from cactus, the present study investigated the effect of polysaccharide-degrading enzymes [Rapidase-Viscozyme mixture, 1/3 (v/v)] treatment under high hydrostatic pressure (HHP).

RESULTS

The dry weight of the extract increased with the use of increasing pressure regardless of enzyme treatment. However, the polyphenol content showed a tendency to decrease with the increase in pressure in the cactus extract with or without enzyme treatment. The enzyme-assisted extraction resulted in an increase of dry weight and polyphenol content in the cactus extract. The total sugar and reducing sugar contents of the cactus extract increased with increasing pressure in enzyme-assisted extraction. The uronic acid content of the cactus extract showed a pattern similar to that of the reducing sugars. The enzyme-assisted extraction also increased the contents of taxifolin, quercetin and isorhametin. The cactus extract obtained through enzyme-assisted extraction showed intense scavenging activity of both DPPH and ABTS radicals. The crude polysaccharides isolated from the extract (51.2% at 1000 µg mL⁻¹ for HHP extraction at 300 MPa) had higher anti-complementary activity than the others except for lipopolysaccharide (60.00% at 1000 µg mL⁻¹). HHP extraction and enzyme-assisted extraction using HHP showed an increase of anti-complementary activity compared with the heat and enzyme controls, respectively.

CONCLUSION

Overall, the use of HHP in enzyme-assisted extraction resulted in more efficient extraction than the use of enzyme treatment alone.

Biological activities of Schottenol and Spinasterol, two natural phytosterols present in argan oil and in cactus pear seed oil, on murine miroglial BV2 cells

The objective of this study was to evaluate the biological activities of the major phytosterols present in argan oil (AO) and in cactus seed oil (CSO) in BV2 microglial cells. Accordingly, we first determined the sterol composition of AO and CSO, showing the presence of Schottenol and Spinasterol as major sterols in AO. While in CSO, in addition to these two sterols, we found mainly another sterol, the Sitosterol. The chemical synthesis of Schottenol and Spinasterol was performed. Our results showed that these two phytosterols, as well as sterol extracts from AO or CSO, are not toxic to microglial BV2 cells. However, treatments by these phytosterols impact the mitochondrial membrane potential. Furthermore, both Schottenol and Spinasterol can modulate the gene expression of two nuclear receptors, liver X receptor (LXR)-α and LXRβ, their target genes ABCA1 and ABCG1. Nonetheless, only Schottenol exhibited a differential activation vis-à-vis the nuclear receptor LXRβ. Thus Schottenol and Spinasterol can be considered as new LXR agonists, which may play protective roles by the modulation of cholesterol metabolism.

Extraction, stability, and separation of betalains from Opuntia joconostle cv. using response surface methodology

Betalains were extracted and analyzed from Opuntia joconostle (the prickly pear known as xoconostle in Mexico). For the extraction, two solvent systems were used, methanol/water and ethanol/water. A three-variable Box-Behnken statistical design was used for extraction: solvent concentration (0-80%, v/v), temperature (5-30 °C), and treatment time (10-30 min). The extraction and stability of betalains from xoconostle were studied using response surface methodology (RSM). Techniques such as UV-vis, column chromatography, and HPLC were employed for the separation and analysis of the main pigments present in the extracts. Maximum pigment concentration (92 mg/100 g of fruit) was obtained at a temperature of 15 °C and a time of 10 min for methanol/water (20:80), whereas maximum stability of the pigment was observed at pH 5 and a temperature of 25 °C. HPLC chromatograms showed the main betalains of the xoconostle characterized were betalain, betanidin, and isobetalain.

Textile dyes removal from aqueous solution using Opuntia ficus-indica fruit waste as adsorbent and its characterization

For this research, three different adsorbents, one untreated and two chemically activated, were prepared from Opuntia ficus-indica fruit waste. By the construction of adsorption isotherms, its adsorption capabilities and the viability of its use in the removal of textile basic and direct type dyes were determined. It was found that the adsorbent with the most adsorption capacity for basic dyes was the one activated with NaClO, and, for direct dyes, it was the one activated with NaOH. Langmuir and Freundlich equations isotherms were applied for the analysis of the experimental data. It was found that the Freundlich model best described the adsorption behavior. The adsorption capacity was improved when the pH of the dye solution had an acid value. The specific surface area of the adsorbents was calculated by means of methylene blue adsorption at 298 K to stay within a range between 348 and 643 m(2) g(-1). The FTIR spectroscopic characterization technique, the SEM, the point of zero charge, and the elemental analysis show the chemical and physical characteristics of the studied adsorbents, which confirm the adsorption results obtained.

Functional and hypoglycemic properties of nopal cladodes (O. ficus-indica) at different maturity stages using in vitro and in vivo tests

Nopal (Opuntia ficus-indica) cladodes are recommended for their therapeutic properties; their maturity stage may affect their biological properties. Cladodes of three maturity stages, from the same crop and location, were dehydrated and evaluated for some of their physicochemical and nutritional characteristics and antidiabetic properties. The flours of small and medium cladodes (SCF and MCF, respectively) had higher contents of dietary fiber, water absorption, swelling, and viscosity compared to those of the large cladode flour (LCF). Streptozotocin-induced diabetic rats, treated with MCF and SCF (doses of 50 mg/kg body weight), showed reduction of postprandial blood glucose on 46.0 and 23.6%, respectively (p < 0.05), in relation to the control; and LCF had no significant effect. In vitro, glucose diffusion tests showed similar ranking by the two former samples, whereas the latter was close to the control. Cladode maturity stages showed different fiber content and produced suspensions with differences in viscosity, which may affect in vitro and in vivo glucose responses.

Antioxidant and anticlastogenic capacity of prickly pear juice

Plants belonging to the genus Opuntia spp. are the most abundant of the Cactaceae family, grown throughout America and the Mediterranean central area. Its fruit, known as cactus pear or prickly pear, is an oval berry grouped in different colors. Some studies have shown its antioxidant activities which may help in preventing chronic pathologies such as diabetes. The purpose of the study was to evaluate the antioxidant capacity of three varieties of prickly pear juice (red-purple, white-green and yellow-orange) in five different concentrations (100, 250, 500, 750, and 1000 mg/mL) by DPPH (1,1-diphenyl-2-picrylhydrazyl radical) colorimetric method, selecting the best variety to determine its anticlastogenic potential against methyl methanesulfonate (MMS). The results indicate that the highest antioxidant was found in the juice of the prickly pear red-purple variety (PPRP), in all concentrations. Its anticlastogenic potential was therefore evaluated with a micronucleus assay. The experiment was run over two weeks. A negative control was included along with a positive control with MMS (40 mg/kg), a group of mice treated with PPRP (25 mL/kg), and three groups with PPRP (in doses of 25, 16.5 and 8.3 mL/kg) plus the mutagen. The PPRP was administered daily by oral gavage and the MMS was injected intraperitoneally five days prior to the end of the experiment. Blood samples were obtained at 0, 24, 48, 72 and 96 h in order to determine the frequency of micronucleated polychromatic erythrocytes (MNPE). The results indicated that PPRP is not a genotoxic agent, on the contrary, it may reduce the number of MNPE. In this regard, the PPRP showed an anticlastogenic effect directly proportional to its concentrations. Thus, the highest protection was obtained with a concentration of 25 mL/kg after 48 h of treatment.

Effects of ultrasound treatment in purple cactus pear (Opuntia ficus-indica) juice

Cactus pear (Opuntia ficus-indica) fruit is a berry with a tasty pulp full of seeds that constitutes about 10-15% of the edible pulp. In Mexico, cactus pear is mainly consumed fresh, but also has the potential to be processed in other products such as juice. The objective of this study was to evaluate the effect of different ultrasound conditions at amplitude levels ranging (40% and 60% for 10, 15, 25 min; 80% for 3, 5, 8, 10, 15 and 25 min) on the characteristics of purple cactus pear juice. The evaluated parameters were related with the quality (stability, °Brix, pH), microbial growth, total phenolic compounds, ascorbic acid and antioxidant activity (ABTS, DPPH and % chelating activity) of purple cactus pear juices. The ultrasound treatment for time period of 15 and 25 min significantly reduced the microbial count in 15 and 25 min, without affecting the juice quality and its antioxidant properties. Juice treated at 80% of amplitude level showed an increased of antioxidant compounds. Our results demonstrated that sonication is a suitable technique for cactus pear processing. This technology allows the achievement of juice safety and quality standards without compromising the retention of antioxidant compounds.

Optimum extraction of polysaccharides from Opuntia dillenii and evaluation of its antioxidant activities

Response surface methodology (RSM) was applied to optimize the extraction of crude polysaccharides from Opuntia dillenii (Ker-Gaw) Haw. A three-level, four-variable Box-Behnken design was employed to obtain the best possible combination of extraction temperature (80-90 °C), extraction time (50-70 min), number of extraction cycle (1-3 times), and ratio of water to raw material (8:1-12:1, v/w) for maximum yield of crude polysaccharide. Besides, the antioxidant capacity of crude polysaccharide was evaluated by DPPH assay. The results showed that optimized extraction conditions were extraction temperature 85 °C, extraction time 63.7 min, extraction 2 times and ratio of water to raw material 11.14:1. Under these conditions, the experimental yield was 27.36 ± 0.21%, which is well in close agreement with the value (27.44%) predicted by RSM model. Pharmacological test showed that O. dillenii crude polysaccharides had a good antioxidant activity.

Determination of some mineral contents of prickly pear (Opuntia ficus-indica L.) seed flours

The aim of this study was to determine some mineral contents of prickly pear (Opuntia fıcus-indica L.) seeds collected from different locations. The mineral contents of seeds were established by inductively coupled plasma atomic emission spectrometry. All the seeds contained Ca, K, Mg and P at high levels. Calcium content ranged between 268.5 (sample no. 11) and 674.8 ppm (sample no. 4). The level of K changed between 346.7 (sample no. 1) and 676.1 ppm (sample no. 13). Phosphorus content of seeds varied between 1,173.6 (sample no. 14) and 1,871.3 ppm (sample no. 1). It is apparent that seeds are good sources of the macro and micro minerals and can be consumed as a food ingredient to provide nutrition.

Purification and characterization of an amylase from Opuntiaficus-indica seeds

BACKGROUND

In Tunisia, prickly pear fruit grow spontaneously; it is consumed as fresh fruit, juice or jam. When the fruit is used for juice production, the seeds are discarded and go to waste. Our study aimed to extract biomolecules from seeds by producing value-added products from the fruits.

RESULTS

An amylase from Opuntia ficus-indica seeds was extracted and purified to homogeneity. An increase in specific activity of 113-fold was observed. The apparent molecular mass of the enzyme is 64 kDa. The optimum pH and temperature for enzyme activity were pH 5 and 60 °C, respectively. Under these conditions, the specific activity is 245.5 U mg(-1) . The enzyme was activated by Co(2+) and Mg(2+) (relative activity 117% and 113% respectively) at lower ion concentrations. It was strongly inhibited by Mn(2+) and Fe(2+) . Cu(2+) inhibited totally the activity of this enzyme, but Ca(2+) has an inhibitory effect which increases with ion concentration.

CONCLUSION

The extracted enzyme belongs to the exo type of amylases and is classified as a β-cyclodextrin glycosyltransferase since it generates mainly β-cyclodextrin from starch. It exhibits high thermal stability and a broad range of pH stability, making it a promising prospect for industrial and food applications.

Evaluation of the suspending properties of two local Opuntia spp. mucilages on paracetamol suspension

Some excipients are currently available for the formulation of pharmaceutical suspensions. The purpose of this study is to develop cheap and effective natural excipient that can be used as an effective alternative for the formulation of pharmaceutical suspensions. The suspending properties of Opuntia ficus-indica and Opuntia stricta mucilages (family Cactaceae) were evaluated comparatively with that of NaCMC at concentration range of 2-6% (w/v) in Paracetamol suspension. Sedimentation volume (%) (with and without electrolyte), rheology, redispersibility, and dissolution rate of the suspensions were employed as evaluation parameters. The values obtained were used as basis for comparison of the suspending agents. The apparent viscosities of the suspensions in all the suspending agents concentration levels and applied shear rates were in the order of NaCMC>OS>OFI with non-Newtonian flow and accordingly the flow rates of the suspensions were in the order of OFI > OS > NaCMC. The sedimentation volumes (%) of the suspensions in all the suspending agent concentration levels were higher for OS followed by OFI and then NaCMC. The high sedimentation volumes (%) of suspensions, in turn, were accompanied by ease of redispersibility of that order. The effect of electrolyte on sedimentation volume (%) had dual effect. It was only the suspensions that had NaCMC that showed increase in sedimentation volume (%) in all molar NaCl concentration. However, in suspensions that had mucilages of OS and OFI, an initial increase in sediment volumes (%) were accompanied by decrease after 1x10(-3)M and 1x10(-2)M of NaCl, respectively. Dissolution of the suspensions which had mucilages attained the acceptable ranges (> 80% drug release in 30 min) in 5 min. Similarly, except A6 formulations A2, A3, A4 and A5 have attained the limit but the release was not as quick as the previous formulations. Hence, it can be concluded that mucilages of Opuntia spp. (Opuntia ficus-indica and Opuntia stricta) can be used as alternatives to NaCMC as suspending agent in suspension formulations.

A natural fiber complex reduces body weight in the overweight and obese: a double-blind, randomized, placebo-controlled study

OBJECTIVE

A proprietary natural fiber complex (Litramine IQP G-002AS) derived from Opuntia ficus-indica, and standardized on lipophilic activity, was previously shown in preclinical and human studies to reduce dietary fat absorption through gastrointestinal (GI) fat binding. Here, we investigated the efficacy and safety of IQP G-002AS in body weight reduction.

DESIGN AND METHODS

One hundred twenty-five overweight and obese adults participated in the study. Subjects were advised on physical activity, and received nutritional counseling, including hypocaloric diet plans (30% energy from fat and 500 kcal deficit/day). After a 2-week placebo run-in phase, subjects were randomized to receive either 3 g/day of IQP G-002AS (IQ) or a placebo. The primary endpoint was change in body weight from baseline; secondary endpoints included additional obesity measures and safety parameters.

RESULTS

One hundred twenty-three subjects completed the 12-week treatment phase (intention-to-treat (ITT) population: 30 male and 93 female; mean BMI: 29.6 ± 2.8 kg/m(2) and age: 45.4 ± 11.3 years). The mean body weight change from baseline was 3.8 ± 1.8 kg in IQ vs. 1.4 ± 2.6 kg in placebo (P < 0.001). More IQ subjects lost at least 5% of their initial body weight compared to placebo (P = 0.027). Compared with placebo, IQ also showed significantly greater reduction in BMI, body fat composition, and waist circumference. IQ was well tolerated with no adverse reactions reported.

CONCLUSIONS

These results suggest that the natural fiber complex Litramine IQP G-002AS is effective in promoting weight loss.

Effect of different film packaging on microbial growth in minimally processed cactus pear (Opuntia ficus-indica)

Microorganisms are natural contaminants of fresh produce and minimally processed products, and contamination arises from a number of sources, including the environment, postharvest handling and processing. Fresh-cut products are particularly susceptible to microbial contaminations because of the changes occurring in the tissues during processing. In package gas composition of modified atmosphere packaging (MAP) in combination with low storage temperatures besides reducing physiological activity of packaged produce, can also delay pathogen growth. Present study investigated on the effect of MAPs, achieved with different plastic films, on microbial growth of minimally processed cactus pear (Opuntio ficus-indica) fruit. Five different plastic materials were used for packaging the manually peeled fruit. That is: a) polypropylene film (Termoplast MY 40 micron thickness, O2 transmission rate 300 cc/m2/24h); b) polyethylene film (Bolphane BHE, 11 micron thickness, O2 transmission rate 19000 cc/m2/24h); c) polypropylene laser-perforated films (Mach Packaging) with 8, 16 or 32 100-micron holes. Total aerobic psychrophilic, mesophilic microorganisms, Enterobacteriaceae, yeast, mould populations and in-package CO2, O2 and C2H4 were determined at each storage time. Different final gas compositions, ranging from 7.8 KPa to 17.1 KPa O2, and 12.7 KPa to 2.6 KPa CO2, were achieved with MY and micro perforated films, respectively. Differences were detected in the mesophilic, Enterobacteriaceae and yeast loads, while no difference was detected in psychrophilic microorganisms. At the end of storage, microbial load in fruits sealed with MY film was significantly lower than in those sealed with BHE and micro perforated films. Furthermore, fruits packed with micro-perforated films showed the highest microbial load. This occurrence may in part be related to in-package gas composition and in part to a continuous contamination of microorganisms through micro-holes.

Antihyperlipidemic effect of methanolic extract from Opuntia joconostle seeds in mice fed a hypercholesterolemic diet

The purpose of this study was to evaluate the hypolipidemic effect of a methanolic extract from Opuntia joconostle seeds fed to mice in a hypercholesterolemic diet. Acute toxicity of the methanolic extract was investigated by an established method. Phenolic composition and antioxidant activity were determined by high-performance liquid chromatography and DPPH, respectively. The total phenolic content of Opuntia joconostle seeds was 47.85 ± 1.29 mg gallic acid equivalents/g dry weight. The main phenolic compounds were identified as quercetin, rutin, and cafeic acid. Percent inhibition of DPPH⁺ was 49.76 ± 0.49 %. The oral LD₅₀ for the methanolic extract from the Opuntia joconostle seeds was >5,000 mg/kg BW. Mice fed a hypercholesterolemic diet for six days exhibited significantly (P ≤ 0.001) higher plasma lipid levels than mice fed a normal diet. Remarkably, supplementation with methanolic extract from Opuntia joconostle at doses of 1, 2, and 5 g/kg body weight significantly (P ≤ 0.001) prevented the increase in total cholesterol, low-density lipoprotein cholesterol, triglycerides level, and atherogenic index. Similar concentrations of the HDL cholesterol were observed in both treated and control groups. A significant dose-dependent reduction in lipid levels was noted for treated groups compared to the hypercholesterolemic group. We attribute this result to the seeds' phenolic composition. This methanolic extract has potential to be included in short-term hypercholesterolemia treatment regimens as it exhibits hypolipidemic activity with no apparent toxic manifestations.

Betacyanin and other antioxidants production during growth of Opuntia stricta (Haw.) fruits

Mature cactus pears from Opuntia stricta have a dark purple color due to high betacyanin concentration, whose biosynthesis is initiated with the amino acid L-tyrosine as a primary precursor. This study followed the maturation and ripening processes of Opuntia stricta fruits to harvest them at high betacyanin and other antioxidant concentrations. Fruits lasted 9 months for final ripening. Physical and compositional changes at different maturation and ripening stages have been determined. Thus, ripe fruits were around 4.72 ± 0.10 cm length, 2.94 ± 0.05 cm diameter and 22.71 ± 0.20 g weight; moisture and pH were maintained at 87.05 ± 0.19 % and 3.37 ± 0.12, respectively. Purple pigment production started in the ovary of immature fruits four months after anthesis (MAA). Concentration of all analyzed metabolites increased from immature (4 MAA) until ripe (9 MAA) stage. In ripe fruits, reducing sugars were 4.72 ± 0.54 g/100 g ff and total phenols 135.17 ± 0.68 mg gallic acid/100 g ff. Metabolites identified by HPLC were the betacyanins: betanin (60.17 ± 1.08 mg/100 g ff), isobetanin (7.58 ± 0.94 mg/100 g ff) and betanidin (13.48 ± 0.87 mg/100 g ff). Also, L-ascorbic acid (35.03 ± 1.06 mg/100 g ff) and L-tyrosine (4.43 ± 0.73 mg/100 g ff) were determined. Furthermore, the addition of L-tyrosine or L-dopa to fruit pulp of moderately ripe fruits, increased betacyanin concentrations 17 (103.3 ± 3.8 mg/100 g) and 32 % (114.3 ± 4.1 mg/100 g), respectively.

Characterization of ammonium retention processes onto cactus leaves fibers using FTIR, EDX and SEM analysis

In order to reduce the impact of nitrogen pollution and to increase the agronomic value of plant wastes to be reused as organic fertilizer, we have investigated the removal of ammonium from aqueous solutions onto cactus leave fibers (CLF), and the mechanisms involved in the retention of ammonium at CLF surface. The results showed that ammonium retention onto these fibers occurred for a wide pH (6-10) and temperature ranges (20-60°C) and the biosorption potential of CLF increased with temperature from 1.4 to 2.3 mg g(-1) for initial concentration of 50 mg L(-1). The modeling studies showed that the ammonium biosorption was well described by the pseudo-second-order model, predicting therefore, chemisorption interactions-type at earlier stages and by intraparticle diffusion at later stages. Biosorption is governed by film diffusion process at higher concentrations and by particle diffusion process at higher temperatures. The surface of CLF determined by SEM revealed the presence of cracks and cavities which may allow the intraparticle diffusion and the ion exchange processes. Moreover, FTIR and EDX analysis before and after ammonium retention showed that the main mechanisms involved in the removal of ammonium were the ionic exchange by calcium ions as well as H(+) and the complexation with carboxylic, alcoholic and phenolic groups.

Resin glycosides from the aerial parts of Operculina turpethum

Three glycosidic acids, turpethic acids A-C, and two intact resin glycosides, turpethosides A and B, all having a common pentasaccharide moiety and 12-hydroxy fatty acid aglycones of different chain lengths, were obtained from the aerial parts of Operculina turpethum. Their structures were elucidated by spectroscopic analyses and chemical correlations. The aglycones were characterized as 12-hydroxypentadecanoic acid in two compounds, 12-hydroxyhexadecanoic acid in two other components, and 12-hydroxyheptadecanoic acid in the fifth compound, which were all confirmed by synthesis. The absolute configurations of these aglycones were all established as S by Mosher's method. These compounds represent the first examples of resin glycosides with a monohydroxylated 12-hydroxy fatty acid as an aglycone, and one compound is the first described resin glycoside having a hydroxylated C(17) fatty acid as its aglycone.

Enhancement of Hsp70 synthesis protects common carp, Cyprinus carpio L., against lethal ammonia toxicity

Exposure to TEX-OE®, a patented extract of the prickly pear cactus (Opuntia ficus indica) containing chaperone-stimulating factor, was shown to protect common carp, Cyprinus carpio L., fingerlings against acute ammonia stress. Survival was enhanced twofold from 50% to 95% after exposure to 5.92 mg L(-1) NH(3) , a level determined in the ammonia challenge bioassay as the 1-h LD50 concentration for this species. Survival of TEX-OE®-pre-exposed fish was enhanced by 20% over non-exposed controls during lethal ammonia challenge (14.21 mg L(-1)  NH(3) ). Increase in the levels of gill and muscle Hsp70 was evident in TEX-OE®-pre-exposed fish but not in the unexposed controls, indicating that application of TEX-OE® accelerated carp endogenous Hsp70 synthesis during ammonia perturbation. Protection against ammonia was correlated with Hsp70 accretion.

Time-dependent bioactivity of preparations from cactus pear (Opuntia ficus indica) and ice plant (Mesembryanthemum crystallinum) on human skin fibroblasts and keratinocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Traditionally and nowadays preparations from two xerophytic plants, the ice plant and cactus pear are used in dermatologic and cosmetic preparations. In spite of their daily use, little is known concerning the bioactivity of such extracts on skin cells. The purpose of this study was to investigate the effect of pressed juices from ice plant (McP) and two cactus pear polysaccharides (cold water soluble, NwPS; non swelling pectin, NPec) on the cell physiology of normal human dermal fibroblasts (NHDF) and HaCaT-keratinocytes due to composition, concentration and incubation time.

MATERIALS AND METHODS

Cactus pear polysaccharides were analyzed by high performance anion exchange chromatography with pulsed amperometric detection after hydrolysis with trifluoroacetic acid. Ice plant pressed juices were filtrated through a 1.2 μm (McPI) and 0.2 μm filter (McPII). Cell proliferation was measured with BrdU incorporation assay. Reduction of tetrazolium salts was applied to determine the metabolic activity (MTT) while necrotic effects were assessed by LDH-release measurements.

RESULTS

Cactus pear polysaccharides differed predominantly in their glucose and uronic acid content. The filtration of pressed juices altered the amounts of high molecular weight compounds. The proliferation of NHDF and HaCaTs was significantly stimulated by cactus pear polysaccharides and ice plant pressed juices not until 72 h of incubation. McPI significantly increased the proliferation of NHDF and HaCaTs while significant effect of McPII was only observed in case of HaCaT-keratinocytes. A dependence on concentration was not observed. Metabolic activity was neither influenced by McPI nor by McPII independent of incubation time. The HaCaT proliferation was not significantly influenced by low concentrations of cactus pear polysaccharides however it was inhibited by 100 μg/mL NPec. 100 μg/mL of NwPS and 1 μg/mL NPec stimulated the proliferation of fibroblasts. The metabolic activity of NHDF was not affected neither by NPec nor by NwPS. Independent of the used concentration NwPS significantly enhanced the metabolic activity of HaCaTs after 48 h of incubation.

CONCLUSIONS

Pressed juices of common ice plant and polysaccharides of cactus pear influenced the cell physiology of human keratinocytes and fibroblasts predominantly in a time-dependent manner. The effect was also be related to the concentration and composition as well as the investigated cell type.

Acute toxicity of Opuntia ficus indica and Pistacia lentiscus seed oils in mice

Opuntia ficus indica and Pistacia lentiscus L. seeds are used in traditional medicine. The objective of this study was to investigate the toxicity of the fixed oil of Opuntia ficus indica and Pistacia lentiscus L. seeds in mice through determination of LD₅₀ values, and also the physicochemical characteristics of the fixed oil of these oils. The acute toxicity of their fixed oil were also investigated in mice using the method of Kabba and Berhens. The fixed oil of Pistacia lentiscus and Opuntia ficus indica seeds were extracted and analyzed for its chemical and physical properties such as acid value, free fatty acid percentage (% FFA), iodine index, and saponification value as well as refractive index and density. LD₅₀ values obtained by single doses, orally and intraperitoneally administered in mice, were respectively 43 ± 0,8 ;[40.7- 45.4 ] ml/kg body wt. p.o. and 2.72 ± 0,1 ;[2.52-2.92] ml/kg body wt. i.p. for Opuntia ficus indica ; and 37 ± 1 ;[34.4 - 39.8 ] ml/kg body wt. p.o. and 2.52 ± 0,2 ;[2.22 - 2.81 ] ml/kg body wt. i.p. for Pistacia lentiscus respectively. The yields of seed oil were respectively calculated as 20.25% and 10.41%. The acid and free fatty acid values indicated that the oil has a low acidity.

Effects of drying process on the physicochemical properties of nopal cladodes at different maturity stages

Chemical proximate analysis was done in order to determine the changes of nutritional characteristics of nopal powders from three different maturity stages 50, 100, and 150 days and obtained by three different drying processes: freeze dried, forced air oven, and tunnel. Results indicate that nopal powder obtained by the process of freeze dried retains higher contents of protein, soluble fiber, and fat than the other two processes. Also, freeze dried process had less effect on color hue variable. No changes were observed in insoluble fiber content, chroma and lightness with the three different drying processes. Furthermore, the soluble fibers decreased with the age of nopal while insoluble fibers and ash content shows an opposite trend. In addition, the luminosity and hue values did not show differences among the maturity stages studied. The high content of dietary fibers of nopal pad powder could to be an interesting source of these important components for human diets and also could be used in food, cosmetics and pharmaceutical industry.

Effect of Opuntia streptacantha Lem. on alpha-glucosidase activity

ETHNOPHARMACOLOGICAL RELEVANCE

In Mexico, Opuntia streptacantha is used as part of a traditional medicine in the treatment of diabetes mellitus. Several studies have reported an anti-hyperglycemic effect from the plant, but none have focused on finding a mechanism of action to explain these results. This paper focuses on one of the most recurrent hypotheses for the effect of O. streptacantha: the mechanism of action is the hydrolysis of disaccharides, either by enzymatically inhibiting the alpha glucosidase inhibitors (AGIs) or mechanically acting as a barrier.

MATERIALS AND METHODS

To test our hypothesis, three different experiments were performed. A maltose tolerance test was carried out using the total extract (TE) and the juice of the plant. Six different extracts were tested in a free-enzyme assay, four of which were aqueous extracts varying according to the procedure of removing the insoluble particles in an attempt to reduce the loss of the water-soluble compounds. The main component of the total extract, a derivative of (4-hydroxy)-phenyl acetic acid, was also tested. For both the maltose tolerance test and the free-enzyme assay, acarbose was used as a control drug. Finally, an everted small intestine assay was also performed.

RESULTS AND CONCLUSIONS

The maltose tolerance test confirmed that an anti-hyperglycemic effect occurs at doses of 100 mg/kg TE and 4 mL/kg juice. No inhibition on AGIs was observed in the free-enzyme assay, and neither a mechanic nor enzymatic effect on disaccharide hydrolysis was observed in the everted intestine assay.

CONCLUSIONS

The anti-hyperglycemic effect of O. streptacantha was confirmed, and the results presented here contribute to the understanding that this effect is not due to the action on alpha-glucosidases or related to the intestinal hydrolysis of disaccharides.

[Immunomodulatory effects of Opuntia dillenii polysaccharides on specific immune function of mice]

OBJECTIVE

To investigate specific immune modulation of Opuntia dillenii polysaccharides (ODPs) on mice (body fluid and cells).

METHODS

An immunosuppressed murine model was induced by intraperitoneal injection of cyclophosphamide (Cy, ip). The intraserous hemolysin IgM, IgG levels, the proliferation of spenocytes and the proportion of T lymphocyte subsets in peripheral blood were determined after the mice treated by ODPs. Proliferative effects of ODP-I, the main component purified from ODPs, on the lymphocytes in vitro were also studied.

RESULTS

ODPs could significantly increase intraserous IgM and IgG levels, significantly enhance the proliferation of T and B lymphocytes and restore them to normal level. ODPs significantly reduced the percentage of CD4+ T lymphocytes subset, therefore significantly reduced the proportion of CD4+ and CD8+ T lymphocytes of peripheral blood from immunosuppressive mice and restored it to normal level. ODP-I significantly enhanced the natural proliferation of splenic lymphocyte and assisted the proliferation of T and B lymphocytes which induced by mitogen ConA or LPS.

CONCLUSION

ODPs can enhance the specific immune function of immunosuppressed mice and the proliferation of lymphocytes in vitro.

Evaluation of antioxidant and antiulcerogenic activities of Opuntia ficus indica f. inermis flowers extract in rats

The Opuntia ficus indica f. inermis methanolic flowers extract (OMFE) was phytochemical studied, in vitro tested for their potential antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH), reducing power, linoleic acid peroxidation assays and in vivo evaluated for its ability to prevent ethanol-induced gastric ulcer in rats. The OMFE was rich in polysaccharide, phenolics and flavonoids contents and exhibited a moderate in vitro antioxidant activity when compared with (+)-catechin and ascorbic acid. Pre-treatment with OMFE at oral doses 250, 500 and 1000 mg/kg body weight was found to provide a dose-dependent protection against ethanol-induced gastric ulcer by averting the deep necrotic lesions of the gastric epithelium, by preserving normal antioxidant enzymes activities, by inhibiting the lipid peroxidation, the oxidation of protein and the DNA fragmentation in gastric mucosa. The antiulcerogenic activity of OMFE might be due to a possible synergistic antioxidant and antihistaminic-like effects.

Betalain: a particular class of antioxidant pigment

We have analyzed the stability of betalains in juices prepared from Moroccan yellow cactus pears (Opuntia ficus indica (L.) Mill.) as a function of temperature and pH. The experiments were carried out at temperatures ranging from 80 to 100 degrees C with juices at pH 3.5, 5 and 6.5. The degree of pigment retention decreased when the temperature increased. The degradation constant rates were determined for thermal degradation rates of pseudo-first order. The Arrhenius plot obtained for the degradation of betaxanthin from the yellow fruits was not linear. Regardless of the temperature of treatment, the lowest degradation was obtained for pH 5. When some stabilizers were tested for the protection of pigments, the results showed that ascorbic acid was a better protective agent at pH 3.5, increasing the protection by 40%. The inhibitive action of betalain pigments extracted from cactus pears towards corrosion of stainless steel in phosphoric acid was investigated using electrochemical polarization and electrochemical impedance spectroscopy (EIS) methods. It was found that the presence of natural pigments reduces the corrosion rate of the tested metal, especially on addition of the red pigments (97%). The inhibition efficiency increases as the pigment concentration of extracts increases. It was also found that the pigments tested act as mixed inhibitors. The inhibitive action of the extracts is discussed in term of adsorption and that such adsorption follows a Langmuir adsorption isotherm. The calculated values of the free energy of adsorption indicated that the adsorption process is spontaneous.

Comparative analyses of total phenols, antioxidant activity, and flavonol glycoside profile of cladode flours from different varieties of Opuntia spp

The phenolic, flavonoid, and antioxidant contents of methanol extracts of nine samples of Mexican cactus ( Opuntia spp.) cladodes processed into flours were studied. Opuntia undulata contained the highest amount of phenols [905.08 ± 64.51 μg of gallic acid equivalents (GAE)/g]. The oxygen radical absorbance capacity (ORAC) of the cladode flour extracts indicated that Opuntia robusta var. Gavia [738.8 ± 89.9 μmol of Trolox equivalents (TE)/g] contained the highest antioxidant capacity. ORAC values significantly correlated to total phenols but not to flavonoid contents and were comparable to cranberries and blackberries. Glycosidic forms of isorhamnetin and kaempferol were identified via high-performance liquid chromatography-photodiode array (HPLC-PDA) and HPLC-mass spectrometry (MS), with isorhamnetin being the most abundant flavonol in all samples, except for Opuntia lindheimeri . The effectiveness of acid hydrolysis varied among species because of the different flavonol profiles. For some varieties, the triglycosidic forms were partially acid-hydrolyzed, giving an increase in the content of diglycosides. Optimization of hydrolysis for each species is required to estimate the total amount of each flavonol.

Antidiabetic effect of a newly identified component of Opuntia dillenii polysaccharides

The aim of this study was to determine the most effective hypoglycemic component of polysaccharides from Opuntia dillenii Haw. by preliminary screening and to specifically study the antidiabetic effects of O. dillenii polysaccharide (ODP)-Ia in mice with streptozotocin (STZ)-induced diabetes. Three kinds of ODPs - ODP-Ia, ODP-Ib, and ODP-II' - were isolated by using an ultrasonic extraction method and diethylaminoethyl (DEAE)-Sepharose fast-flow column chromatography. The mice were administered ODPs for 3 weeks. Gavage administration of ODP-Ia significantly decreased (P<0.05) their intake of food and water; the fasting levels of blood glucose (BG), total cholesterol (TC), triglycerides (TGs), plasma urea nitrogen (PUN), and malondialdehyde (MDA); and the activity of glucose-6-phosphatase (G-6-Pase). In contrast, it significantly increased (P<0.05) the body weights, hepatic glycogen (HG) levels, high-density lipoprotein cholesterol (HDL-C) levels, and the hepatic superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity in diabetic mice. However, ODP-Ia did not significantly increase insulin levels in the mice with STZ-induced diabetes. We propose that ODP-Ia exerts its antihyperglycemic effect by protecting the liver from peroxidation damage and by maintaining tissue function, thereby improving the sensitivity and response of target cells in diabetic mice to insulin.

Chemical analysis of nutritional content of prickly pads (Opuntia ficus indica) at varied ages in an organic harvest

Opuntia ficus indica, also known as prickly pads, are an important part of the human diet and are also used as forage for livestock. This is an interesting vegetable due the environmental conditions in which it grows and its resistance to climatic extremes; however, little is known about its nutritional properties, especially in the later stages of maturity. The objective of this study was to determine the composition of organic prickly pads (Opuntia ficus indica) at differing stages of growth maturity. Chemical proximate analysis and mineral constituent analysis at different maturation stages were carried out in this investigation. As a result, older prickly pads were found to be an important source of nutritional components such as calcium.

Chemical composition and antidiabetic activity of Opuntia Milpa Alta extracts

Three new compounds, 1-3, and 20 known compounds were isolated from the AcOEt and BuOH extract of edible Opuntia Milpa Alta. The petroleum ether extract was examined by GC and MS. A total of 26 compounds were identified, representing 95.6% of the total extract, phytosterol (36.03%) being the most abundant component, and polyunsaturated fatty acids (18.57%) represented the second largest group, followed by phytol (12.28%), palmitic acid, palmitate (13.54%), vitamin E (4.51%), and other compounds (7.47%). The effects of various extracts from edible Opuntia Milpa Alta (petroleum ether extract, AcOEt extract, BuOH extract, aqueous extract, H₂O parts) and the positive control (received dimethylbiguanide) were tested on streptozotocin (STZ)-induced diabetic mice. The results indicated that all the treatment groups could significantly decrease blood glucose levels in STZ-induced diabetic mice compared to the model control group (P<0.01), except the aqueous extract group (P<0.05). Especially, the petroleum ether extract group and the positive control group showed remarkable decrease of blood glucose levels. Taken together, the results indicate that the petroleum ether extract is the major hypoglycemic part in edible Opuntia Milpa Alta, which may be developed to a potential natural hypoglycemic functional ingredient.

Study of the antioxidant properties of extracts obtained from nopal cactus (Opuntia ficus-indica) cladodes after convective drying

BACKGROUND

The process of convective drying was evaluated in terms of the bioactive compounds contained in nopal samples before and after dehydration. Total polyphenol, flavonoid, flavonol, carotene and ascorbic acid contents were determined in undehydrated and dehydrated samples. Two drying temperatures (45 and 65 °C) and two air flow rates (3 and 5 m s(-1) ) were evaluated. The rheology of samples under the best drying conditions was also studied, since it provides important information regarding processing (mixing, flow processing) as well as the sensory attributes (texture) of rehydrated samples.

RESULTS

Non-Newtonian shear-thinning behaviour was observed for samples dried at 45 °C, while samples dried at 65 °C showed shear-thickening behaviour, possibly caused by thermal chain scission of high-molecular-weight components.

CONCLUSION

The best conditions for bioactive compound preservation were a drying temperature of 45 °C and an air flow rate of 3 m s(-1) , resulting in 40.97 g phenols, 23.41 g flavonoids, 0.543 g β-carotene and 0.2815 g ascorbic acid kg(-1) sample as shown in table 3.

Anti-hyperglycemic effect of Opuntia streptacantha Lem

AIM OF THE STUDY

This experiment studied two extracts of Opuntia streptacantha, a plant used by the Mexican population to treat type 2 diabetes, in different assays to contribute to the understanding of the hypoglycemic mechanism of this plant.

MATERIALS AND METHODS

Two different extracts were prepared and tested: the first extract was a filtrate of the traditional liquefied extract (LE) preparation of the cladode; and the second filtrate extract (FE) is a filtered sample of the first. Both extracts contained a newly identified compound for Opuntia (4-hydroxy)-phenyl acetic acid derivate, they were tested on streptozotocin (STZ)-diabetic rats in a series of two tests. The first test was performed to confirm if STZ-diabetic rats presented a hypoglycemic effect after administration of the extracts (LE 135 mg/kg and FE 27 mg/kg). In the second experiment, the extracts were administered before an oral glucose tolerance test (OGTT) to confirm if they have an anti-hyperglycemic effect (LE 135 mg/kg, FE 12 and 27 mg/kg).

RESULTS

The extracts administered to STZ-diabetic rats did not produce a significant hypoglycemic effect compared to the control group, while the same extracts administered before an OGTT produced an anti-hyperglycemic effect compared to the control group.

CONCLUSIONS

The filtered, traditional LE of the cladode of Opuntia streptacantha produces an anti-hyperglycemic effect when administered before a glucose challenge, and this anti-hyperglycemic effect is maintained after filtering the extract. Administration of both plants can improve glycemic control by blocking the hepatic glucose output, especially in the fasting state. These data support the traditional use of the plants as "agua de uso", a cold infusion of the plant consumed over the course of a day.

Antioxidant and antiulcerogenic activities of Opuntia ficus indica f. inermis root extract in rats

Opuntia ficus indica f. inermis methanolic root extract (ORE) was investigated for phenolic and flavonoids contents, in vitro evaluated for DPPH radical scavenging activity, reducing power and in vivo tested for its gastro-protective ability against 80% ethanol induced ulcer in rats. Phytochemical test of ORE were positive for phenolic and flavonoid contents. DPPH radical scavenging activity and reducing power of ORE showed an EC(50) of 118.65±2.51 μg/ml and 300 μg/ml respectively. In vivo the pre-treatment of rats with ranitidine (50 mg/kg) and 200, 400, and 800 mg/kg doses of ORE significantly (p<0.05) reduced the 80% ethanol induced-ulcer lesion, with a rate of 82.68%, 49.21%, 83.13%, and 92.59% respectively, and prevented the depletion of antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), total glutathione (GSH), and inhibited the increase of myeloperoxidase (MPO) and malondialdehyde (MDA) in rat stomach tissues when compared with ethanol group. Also pre-treatment with ORE marked a dose-dependent attenuation of histopathology changes induced by ethanol. Phenolic and flavonoids wealth, radical scavenging activity, and reducing power, have been implicated for antiulcer property of ORE.

Stabilization of the bioactive pigment of opuntia fruits through maltodextrin encapsulation

Betalains are water-soluble, nitrogen-containing pigments of growing interest in the food industry. They are present in most plants belonging to the order Caryophyllales, where they fulfill the role of anthocyanins, and are divided into two groups: violet betacyanins and yellow betaxanthins. They are bioactive molecules that account for health-promoting properties, recently described for cactus pears (Opuntia). In this work, the characteristic betalain of cactus pears, indicaxanthin, is obtained purely, and its stability is highly promoted by its encapsulation in a maltodextrin matrix. A suitable spray-drying procedure for encapsulation is described, and a bright yellow powder is obtained. The stability is analyzed under different conditions. In the absence of light, pure encapsulated pigment can be stored at 20 °C for months without appreciable loss of the bioactive substance and color variation. Furthermore, free radical scavenging and antioxidant properties of the pigment are studied under the ABTS(•+) radical and ferric reducing antioxidant power assays, in the presence and in the absence of maltodextrins. The stabilization of pure betalain pigments may boost the use of these bioactive and natural coloring molecules.

Opuntia humifusa partitioned extracts inhibit the growth of U87MG human glioblastoma cells

Opuntia humifusa, a member of the Cactaceae family widely distributed in the southern regions of the Korean peninsula, has potential bioactive functions and medicinal benefits. In the present study, we investigated the effect of hexane, ethyl acetate extracts and water partitioned fraction of O. humifusa on proliferation, G1 arrest and apoptosis in U87MG human glioblastoma cells. Glioblastoma cellular proliferation was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, and the effects of O. humifusa partitioned extracts on cell cycle and apoptosis were analyzed by flow cytometry. Our results revealed that when U87MG cells were treated with hexane extracts and water partitioned fraction of O. humifusa, the number of viable cells decreased in a concentration-dependent manner. In addition, water partitioned fractions of O. humifusa induced G1 arrest and non-apoptotic cell death as well as significant increases in ROS production in U87MG cells. In conclusion, water partitioned fractions of O. humifusa induce G1 arrest and inhibit U87MG human glioblastoma cell proliferation.

Determination of antioxidant constituents in cactus pear fruits

An analytical study was carried out on the presence of antioxidant constituents and the in vitro antioxidant capacity in the extracts of three species of Spanish red-skinned cactus pear fruits (Opuntia ficus-indica, Opuntia undulata and Opuntia stricta). The cactus pear fruit extracts were analyzed for determined constituents: ascorbic acid, flavonoids (quercetin, isorhamnetin, myricetin, kaempferol and luteolin), betalains, taurine, total carotenoids and total phenolics. The antioxidant capacity was assessed by means of two different methods: the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (Trolox equivalent antioxidant capacity) method and the 2,2-diphenyl-1-picrylhydrazyl radical method. Opuntia ficus-indica fruit extract had the strongest antioxidant capacity and taurine content. O. stricta fruits were the richest in ascorbic acid and total phenolics, whereas O. undulata fruits showed the highest carotenoid content. Quercetin and isorhamnetin were the main flavonoids detected. This study provides basic information on the presence of bioactive compounds and antioxidant capacity in extracts of cactus pear fruits, in order to consider these extracts as ingredient for the production of health-promoting food.

By-products of Opuntia ficus-indica as a source of antioxidant dietary fiber

Dietary fiber and bioactive compounds are widely used as functional ingredients in processed foods. The market in this field is competitive and the development of new types of quality ingredients for the food industry is on the rise. Opuntia ficus-indica (cactus pear) produces edible tender stems (cladodes) and fruits with a high nutritional value in terms of minerals, protein, dietary fiber and phytochemicals; however, around 20% of fresh weight of cladodes and 45% of fresh weight of fruits are by-products. The objective of this study was therefore to determine the nutritional value of by-products obtained from cladodes and fruits from two varieties of Opuntia ficus-indica, examining their dietary fiber and natural antioxidant compound contents in order to obtain quality ingredients for functional foods and increase the added value of these by-products.

Acute blood glucose lowering effects and long-term safety of OpunDia supplementation in pre-diabetic males and females

AIM OF THE STUDY

The aim of this study was to evaluate the acute and chronic effects of OpunDia (Opuntia ficus-indica) in obese pre-diabetic men and women.

MATERIALS AND METHODS

This double-blind placebo controlled study included participants (age range of 20-50 years) randomly assigned to one of the two groups and given a 16-week supply of either the 200 mg OpunDia (n=15), or placebo (n=14). The acute phase of the study consisted of an oral glucose tolerance test (OGTT) with a 400 mg bolus of OpunDia given 30 min before orally ingesting a 75 g glucose drink. Baseline and post 16-week concentrations of glucose, insulin, hsCRP, adiponectin, proinsulin, Hb1Ac, cholesterol, and a comprehensive metabolic panel were collected along with body composition measured via densitometry (BOD POD). A repeated measures ANOVA was conducted to determine any significant interactions between group and time. Follow-up analysis was performed to determine differences among groups at each time point. Paired t-tests were performed on all variables to determine if any within group differences existed across time.

RESULTS

There was a statistically significant decrease (P<0.05) in the blood glucose concentrations at the 60 (205.92+/-36.90 and 188.84+/-38.43 mg/dL, respectively), 90 (184.55+/-33.67 and 169.74+/-35.16 mg/dL, respectively) and 120 min (159.24+/-17.85 and 148.89+/-24.86 mg/dL, respectively) time points with the pre-OGTT compared to the OpunDia bolus trial. There were no between-group differences found with the OGTT time points, area under the curve, blood chemistry variables (insulin, hsCRP, adiponectin, proinsulin, Hb1Ac), diet analysis variables (carbohydrates, fat, protein and total kcals), body composition variables (fat mass, fat free mass, percent body fat and total body weight), or blood chemistry safety parameters (comprehensive metabolic panel) pre-to-post 16-week intervention.

CONCLUSIONS

This study shows the acute blood glucose lowering effects and the long-term safety of the proprietary product OpunDia, thus supporting the traditional use of Opuntia ficus-indica for blood glucose management.

[Study on in vitro release and transdermal behaviors of mumps cataplasm of complex prescription]

OBJECTIVE

To investigate the in vitro release and transdermal behaviors of mumps cataplasm of complex prescription.

METHODS

The improved Franz difficusion was used and the concentration of drugs was detected. DCS was determined by HPLC and flavanoid contents were determined by UV.

RESULTS

The accumulation skin permeation percentage of DCS and flavanoid was 32% and 21%, respectively, the in vitro release percentage of DCS and flavanoid was 47% and 42%, respectively.

CONCLUSION

The transdermal behavior of mumps cataplasm of complex prescription is an zero-order kinetics progress. The in vitro release behavior is in accordance with the Higuchi equation.

Inhibition of the mechanical activity of mouse ileum by cactus pear (Opuntia Ficus Indica, L, Mill.) fruit extract and its pigment indicaxanthin

We investigated, using an organ bath technique, the effects of a hydrophilic extract from Opuntia ficus indica fruit pulp (cactus fruit extract, CFE) on the motility of mouse ileum, and researched the extract component(s) responsible for the observed responses. CFE (10-320 mg of fresh fruit pulp equivalents/mL of organ bath) reduced dose-dependently the spontaneous contractions. This effect was unaffected by tetrodotoxin, a neuronal blocker, N(omega)-nitro-l-arginine methyl ester, a nitric oxide synthase blocker, tetraethylammonium, a potassium channel blocker, or atropine, a muscarinic receptor antagonist. CFE also reduced the contractions evoked by carbachol, without affecting the contractions evoked by high extracellular potassium. Indicaxanthin, but not ascorbic acid, assayed at concentrations comparable with their content in CFE, mimicked the CFE effects. The data show that CFE is able to exert direct antispasmodic effects on the intestinal motility. The CFE inhibitory effects do not involve potassium channels or voltage-dependent calcium channels but rather pathways of calcium intracellular release. The fruit pigment indicaxanthin appears to be the main component responsible for the CFE-induced effects.

The effect of variety and location on cactus pear (Opuntia ficus-indica) fruit quality

Little is known about the performance of South African cactus pear varieties in different agro-ecological regions. Effects of locality on internal quality parameters of available cactus pear varieties were examined. With only one exception, no significant differences among the mean replication values for the different parameters between the different locations were observed. The differences between mean values for most individual parameters at the three localities were highly significant. Highly significant differences between the mean values for the measured characteristics were observed, not only among the locations (except for the pulp glucose values), but also for the influences of genotype and interaction between locality and genotype. Significant variations existed between mean values of the different characteristics between localities. Genotype x environmental interactions were noted. It was concluded that Meyers is the most appropriate cultivar for economical purposes in South Africa.

Determination of the folate content in cladodes of nopal (Opuntia ficus indica) by microbiological assay utilizing Lactobacillus casei (ATCC 7469) and enzyme-linked immunosorbent assay

Prickly pear cactus has been an important food source in Mexico since ancient times due to its economical and ecological benefits and potential nutraceutical value. Nevertheless, studies on the nutritional aspects and health benefits have been scarce. The purpose of this study was to assess, apparently for the first time, the folate contents of cladodes of nopal by a microbiological assay, using Lactobacillus casei (ATCC 7469) in extracts that were enzymatically treated to release the bound vitamin, employing single, dual, and trienzymatic procedures, and using the enzyme-linked immunosorbent assay (ELISA). We used Opuntia cladodes of different length sizes. The microbiological assay showed some differences among enzyme treatments and sizes of nopal; the trienzyme treatment (alpha-amylase-protease-conjugase) was more efficient in determining the folate content in nopal, giving 5.0 ng/g in the small size cladodes at 54 h of testing time, while ELISA showed no significant differences in the folate content among sizes of cladodes (5.5-5.62 ng/g at 0 min testing time). Both techniques may be used for the assessment of folate content in cladodes, but ELISA is more rapid and reliable.

Anatomical, chemical, and biochemical characterization of cladodes from prickly pear [Opuntia ficus-indica (L.) Mill.]

Opuntia ficus-indica cladodes represent the green stem of the plant and are generally used as animal feed or disposed of in landfills. The present work investigated the anatomical and chemical composition of Opuntia cladodes, which form the basis of their pharmacological effects. Glucose and galacturonic acid were the main sugars of Opuntia cladodes, whereas high-performance liquid chromatography (HPLC) analysis showed the presence of mainly kaempherol and isorhamnetin glycosides (glucoside and rhamnoside). The presence of high amounts of calcium oxalate crystals was demonstrated by light microscopy on fresh and lyophilized cladodes. No antimicrobial activity was observed even after enzymatic treatment. O. ficus-indica cladodes may retain material tightly associated with cell-wall components, and this property will have the potential to greatly reduce the bioavailability of bioactive compounds.

Phenolic composition, antioxidant capacity and in vitro cancer cell cytotoxicity of nine prickly pear (Opuntia spp.) juices

Juices of nine prickly pears (Opuntia spp.) were characterized in terms of color, acidity, sugar content, phenolics, flavonoids, betalains and antioxidant activity and tested in vitro against four cancer cell lines. The juices had pH s, acidities and sugar ranging from 4.27 to 5.46, 0.03 to 0.27% and 8 to 14.7 degrees Brix, respectively. Juices also varied in color from white to purple and contained total phenolics, flavonoids, betaxanthins, betacyanins and antioxidant capacity ranging from 22 to 226 microg gallic acid eq/g, 95 to 374 microg quercetin eq/g, 3 to 189 microg/g, 1.6 to 300 microg/g and 17 to 25 micromoles Trolox eq./mL, respectively. Among the cancer lines tested, viability of prostate and colon cells were the most affected. Moradillo contained the highest flavonoids and diminished both prostate and colon cancer cell viability without affecting mammary or hepatic cancer cells. Rastrero reduced the growth of the four cancer cell lines without affecting normal fibroblast viability. The research shows intervarietal differences among prickly pears in terms of juice properties and phytochemicals that could prevent oxidative stress and cancer.

In vitro digestion of betalainic foods. Stability and bioaccessibility of betaxanthins and betacyanins and antioxidative potential of food digesta

Betalains are considered to be bioactive dietary phytochemicals. The stability of betacyanins and betaxanthins from either fresh foods or manufactured products of cactus pear fruit ( Opuntia ficus indica L. Mill. cv. Gialla and Rossa) and red beet ( Beta vulgaris L. ssp. vulgaris) was assessed in a simulated oral, gastric, and small intestinal digestion and compared with the digestive stability of purified pigments. A minor loss of indicaxanthin, at the gastric-like environment only, and a decrease of vulgaxanthin I through all digestion steps were observed, which was not affected by food matrix. In contrast, food matrix prevented decay of betanin and isobetanin at the gastric-like environment. Loss of betacyanins, either purified or food-derived, was observed during the small intestinal phase of digestion. Betalamic acid accumulated after digestive degradation of purified pigments, but not of food betalains. Betaxanthins were wholly soluble in the aqueous (bioaccessible) fraction after ultracentrifugation of the postintestinal (PI) digesta, whereas release of betacyanins from the matrix was incomplete. PI digesta inhibited dose-dependently the oxidation of methyl linoleate in methanol, an effect not correlated with the betalain content. The data suggest that digestive stability controls bioaccessibility of dietary betaxanthins, whereas additional factors, relevant to the food matrix and style of processing, affect betacyanin bioaccessibility.

Correlation between some nutritional components and the total antioxidant capacity measured with six different assays in eight horticultural crops

The contents of antioxidant nutritional compounds, total soluble phenolics (TSP), vitamin C, vitamin E, beta-carotene, and total carotenoids (TC), were correlated with the total antioxidant capacity (AOC) of hydrophilic (HPE) and lipophilic extracts (LPE) from eight horticultural crops, namely, guava, avocado, black sapote, mango, papaya, prickly pear fruit, cladodes, and strawberry. AOC was measured using six different assays: 2,2'-diphenyl-1-picrylhydrazyl (DPPH), N,N-dimethyl-p-phenylendiamine (DMPD), ferric-ion-reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), Trolox equivalent antioxidant capacity (TEAC), and total oxidant scavenging capacity (TOSC). AOC values from HPE were about 95 times higher than LPE values. HPE of guava had the highest AOC value when evaluated with DMPD, DPPH, FRAP, TEAC, and TOSC assays, whereas with ORAC assay, black sapote had the highest value. HPE of papaya and prickly pear fruit presented the lowest AOC values with all assays. From HPE, vitamin C and TSP contents were highly correlated with AOC for all assays, while from LPE, TC and beta-carotene contents possessed a high correlation with AOC only in the DMPD assay.

Macrophage immunomodulatory activity of polysaccharides isolated from Opuntia polyacantha

Opuntia polyacantha (prickly pear cactus) has been used extensively for its nutritional properties; however, less is known regarding medicinal properties of Opuntia tissues. In the present study, we extracted polysaccharides from O. polyacantha and used size-exclusion chromatography to fractionate the crude polysaccharides into four polysaccharide fractions (designated as Opuntia polysaccharides C-I to C-IV). The average M(r) of fractions C-I through C-IV was estimated to be 733, 550, 310, and 168 kDa, respectively, and sugar composition analysis revealed that Opuntia polysaccharides consisted primarily of galactose, galacturonic acid, xylose, arabinose, and rhamnose. Analysis of the effects of Opuntia polysaccharides on human and murine macrophages demonstrated that all four fractions had potent immunomodulatory activity, inducing production of reactive oxygen species, nitric oxide, tumor necrosis factor alpha, and interleukin 6. Furthermore, modulation of macrophage function by Opuntia polysaccharides was mediated, at least in part, through activation of nuclear factor kappaB. Together, our results provide a molecular basis to explain a portion of the beneficial therapeutic properties of extracts from O. polyacantha and support the concept of using Opuntia polysaccharides as an immunotherapeutic adjuvant.

Identification and quantification of betalains from the fruits of 10 mexican prickly pear cultivars by high-performance liquid chromatography and electrospray ionization mass spectrometry

Qualitative and quantitative analyses of betalain pigments in 10 cultivars/lines of prickly pear (Opuntia spp.) fruit grown in Mexico were conducted with reverse phase high-performance liquid chromatography-diode array detection (HPLC-DAD) coupled with electrospray mass spectrometry (ESI-MS). Betacyanins and betaxanthins were identified by comparison with the UV/vis and mass spectrometric characteristics as well as the retention times of semisynthesized reference betaxanthins. Data revealed that the ratio and concentration of betalain pigments are responsible for the color in the different cultivars, showing the highest betalains content in the fruit of purple colored Camuesa (O. robusta Wendl.) (8.1 mg/g dry fruit), which is comparable to that found in red beet Beta vulgaris L. ssp. Var. Pablo) (8.6 mg/g dry tissue). Yellow betalains were absent in Reyna (O. alba-carpa) prickly pear cultivar. A total of 24 known/unknown betalains were present in the prickly pear fruit samples studied, including 18 betaxanthins and 6 betacyanins. Our results indicate that prickly pear cultivars can be considered as a potential source of yellow and red natural colorants.

Fermentation of Opuntia stricta (Haw.) fruits for betalains concentration

Fermentation of juice and homogenized fruits of Opuntia stricta fruits has been developed and optimized. The aim was to obtain the red food colorant betanin from prickly pear, at high concentration and low viscosity. Among three strains assayed, Saccharomyces cerevisiae var. bayanus AWRI 796 has been the optimum for this process. The optimum temperature value was found to be 35 degrees C for both sugar consumption and pigment preservation. After fermentation, biomass and residual vegetal tissue were discarded by centrifugation. Supernatant was concentrated under vacuum. Therefore, liquid concentrated betanin was obtained, with low viscosity and being sugar free. Besides, bioethanol was obtained as byproduct. Characteristics of the final product obtained were pH 3.41, 5.2 degrees Brix, 9.65 g/L betanin, color strength of 10.8, and viscosity of 52.5 cP. These values are better than obtained by other procedures.