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The fruit of 18 Solanum lycopersicum var. cerasiforme accessions from Mexico were evaluated for total phenolics (TP) by the Folin-Ciocalteau assay, phenolic profiles by high performance liquid chromatography-diode array detection-mass spectrometry (HPLC-DAD-MS), antioxidant activity (AoxA) by 2,2´-azino-bis(3-ethylbenzothiazolin)-6-sulfonic acid (ABTS), 2,2-diphenil-1-pycrilhydrazyl (DPPH), and oxygen radical absorbance capacity (ORAC), and antimutagenic activity (AmuA) by the Ames assay. TP was measured as Gallic Acid Equivalents (GAE) and the AoxA as Trolox Equivalents (TE). TP varied from 37 to 86 mg GAE 100 g−1 fresh weight (fw). The AoxA by ABTS (568-1187 µmol TE 100 g−1 fw) and DPPH (157-350 µmol TE 100 g−1 fw) correlated with TP and the levels of caffeoylquinic acids and rutin. The AmuA did not correlate with the levels of phenolics. Some accessions had higher AoxA and AmuA than those reported for commercial cultivars and also showed high levels of caffeoylquinic acids and rutin; thus, their consumption could have good health promoting effects. [ABSTRACT FROM AUTHOR]

Abstract: The fruit of Vitex mollis Kunth contains water‐soluble melanin (SM), whose properties have been poorly described. This study determined physicochemical characteristics, the inhibition of carbohydrate digestive enzymes (amylase and α‐glucosidase), and antioxidant activity (ABTS, DPPH, ORAC, and β‐carotene bleaching) of SM (partially purified, aqueous extraction), water‐insoluble melanin (IM) (pure, alkali‐acid extraction), and organic (i.e., methanol, ethanol, and methanol : water 8:2 vol/vol) and aqueous extracts of V. mollis fruit. SM and IM were characterized by UV and IR spectroscopy, and their spectra showed signals characteristic of melanins. They also showed similar antioxidant (1,321–2,664 μmol TE/g), and α‐glucosidase inhibitory (IC50 1.48–0.022 mg/mL) activities, values that were better than those of the organic extracts (ABTS < 746 µmol TE/g and IC50 > 4.87 mg/mL, respectively). In addition, SMs showed higher extraction yields than IMs. Therefore, SM shares nutraceutical properties with IM and can be obtained by simple and environmentally friendly methods. Practical applications: Melanins show biological activities (e.g., antioxidant, immunostimulatory, UV‐, and radiation‐protective) and their consumption has been associated with health benefits. However, studies of plant melanins are scarce because their extraction involves harsh pH conditions and the yields are usually low. The results showed that melanin was the main pigment in Vitex mollis fruit and water‐soluble. Moreover, the extraction method was simple, ecological, and produced high yields. Both water‐soluble and water‐insoluble melanins showed similar biological activities (antioxidant and α glucosidase inhibition). Species of Vitex are commonly employed as food and in folk medicine (e.g., premenstrual and gynecological disorders, gastrointestinal problems and inflammation, bacterial infections). Soluble melanins of V. mollis could be used as food supplement or in pharmaceutical preparations. [ABSTRACT FROM AUTHOR]

Echeveria species (Crassulaceae) are used in traditional medicine and some of their biological activities are demonstrated (e.g. antimicrobial, anti-inflammatory, anticancer). However, their chemical composition has been scarcely studied. The methanol extracts (ME) of three Echeveria species (E. craigiana, E. kimnachii and E. subrigida) from Mexico were analyzed for the sterol (GC-MS) and phenolic (HPLC-DAD-ESI-MSn ) composition. Eleven sterols were identified, E. kimnachii showed the highest total content (7.87 mg/g ME), and the main constituents were γ-sitosterol in E. craigiana (33.9%) and E. subrigida (54.4%), and lupenone in E. kimnachii (28.9%). The phenolic analysis showed differences among the Echeveria species, which contained flavonoids derivatives and tannins as the main components. The main flavonoids in E. craigiana were hexoside derivatives of quercetin and isorhamnetin, both with a 3-hydroxy-3-methylglutaroyl substituent; in E. subrigida hexosides of isorhamnetin, quercetin and kaempferol; and E. kimnachii showed the greatest diversity including proanthocyanidins and less common flavonoid derivatives of kaempferol O,O-disubstituted by acyl derivatives. The characteristic phytochemicals of each studied Echeveria species could be responsible of its specific biological activities and useful as chemotaxonomic markers. The kaempferol derivatives in E. kimnachii are rare in nature and they will be isolated and characterized. [ABSTRACT FROM AUTHOR]

Constant retort temperature ( CRT) processes for thermally treated foods are usually time-consuming and have drastic impact on food quality. Variable retort temperature ( VRT) processes may decrease the processing time and may retain better the food nutritional quality. Five isolethal profiles (one CRT and four VRT) for preparing papaya puree (p H 3.8) were designed using pectin methyl esterase as the target enzyme for thermal processing, and their effect on the puree quality was evaluated. The objective was to compare these profiles based on processing time, vitamin C retention, consistency index and color. The VRT isolethal profiles reduced the processing time up to 33.3% compared with CRT, whereas vitamin C, consistency index and chroma were retained up to 65, 71 and 89%, respectively, compared with fresh puree. The best resulting treatment was a VRT upstairs profile (75 C/19 min, 80C/8.5 min, 90C/10.7 min and 6C/20.8 min). The results show that the use of VRT profiles allows retaining the nutritional quality of canned papaya puree. Practical Applications This research explored the use of variable retort temperature to increase product quality and improve processing time in canning of papaya puree. In an upstairs profile, 65% of vitamin C was retained compared with fresh product. The results would be useful for canning of conduction-heated foods. [ABSTRACT FROM AUTHOR]

Introduction. Pithecellobium dulce is a legume native to tropical America that produces edible arils which can be white or red. The plant is also grown in Asia and, to date, predominantly fruits produced in Asia have been the subject of scientific studies. We studied white and red arils produced in America. Materials and methods. White aril and red aril fruits were evaluated in an array of reagent-based assays to determine nutritional and nutraceutical properties. Results and discussion. White arils and red arils showed similar physicochemical characteristics, with high content of vitamin C (79.7–82.6 mg·100 g–1 fresh weight) and dietary fiber (5.83–6.12% fw). The anthocyanin content of red arils (29.5 mg·100 g–1 fw, as cyanidin-3-glucoside equivalents) was similar to that of strawberry. Total phenolics (517 mg·100 g–1 fw, as gallic acid equivalents) and antioxidant activities (ABTS, 224 mg; DPPH, 223 mg, as vitamin C equivalents) of red arils were 1.3 times higher than those in white arils. The methanolic extract of red arils showed a higher α-glucosidase inhibition (IC50 2.9 mg·mL–1) than acarbose (IC50 4.9 mg·mL–1). The methanolic extract [(50, 100 and 500) μg per tube] of red and white arils showed positive-strong antimutagenic activities (inhibition in the range 25–70%) in the assay (Salmonella typhimurium YG1024 strain, 1-nitropyrene as mutagen, 200 ng per tube). We are reporting for the first time remarkably high characteristics (i.e., antioxidant, inhibition of α-amylase and α-glucosidase and content of dietary fiber) of P. dulce fruits, mainly of the red ones; properties which combined permit us to suggest that consumption of these fruits could have beneficial health effects in people with diabetes. [ABSTRACT FROM AUTHOR]

Gnathostoma turgidum is a nematode that parasitizes the stomach of opossums, Didelphis virginiana. Despite its wide distribution in the Americas, its natural life cycle is poorly understood. Recently, we found an endemic area for G. turgidum infection in Sinaloa, Mexico (Díaz-Camacho et al., 2009). Based on sporadic surveys for several years, the prevalence was apparently high in summer and extremely low in winter. To confirm that this is really a seasonal variance, we conducted a longitudinal survey on G. turgidum infection in opossums from November 2007 to November 2008. The results showed amazing seasonal changes in the prevalence, with synchronized migration and maturation of worms in opossums. Between February and March, many juvenile worms, with occasional AL3, were found in the liver, but no worms were found in the stomach. Mature adult worms began to appear in the stomach around April and rapidly increased in number toward July, when all worms resided in the stomach. Then, the worms disappeared almost completely by November. These results suggest that G. turgidum is an annual parasite of the opossum, D. virginiana, in Mexico. [ABSTRACT FROM AUTHOR]

We report for the first time the antioxidant and antimutagenic activities of fractions from Randia echinocarpa fruit, which is a Rubiaceae plant native to Sinaloa, Mexico. This fruit has been traditionally used in the prevention or treatment of cancer, among other diseases. The pulp of the fruit was sequentially extracted with solvents of different polarity (i.e. hexane, chloroform, methanol and water). A high extraction yield was obtained with methanol (72.17% d.w.). The aqueous extract showed the highest content of phenolics (2.27 mg/g as ferulic acid equivalents) and the highest antioxidant activity based on the β-carotene bleaching method (486.15). The commercial antioxidant BHT was used as control (835.05). Antimutagenic activity of the aqueous extract (0–500 μg/tube) was evaluated using the Salmonella microsuspension assay (YG1024 strain) and 1-NP as the mutagen (50 and 100 ng/tube). The aqueous extract was neither toxic nor mutagenic and the percentage of inhibition on 1-NP mutagenicity was 32 and 53% at doses of 50 and 100 ng/tube, respectively. The results of the double incubation assay suggest that the extract inhibited the mutagenicity of 1-NP by a combination of desmutagenic and bioantimutagenic effects. [ABSTRACT FROM AUTHOR]

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