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Byline: P. Collazo-Siques (1), M. E. Valverde (1), O. Paredes-Lopez (1), F. Guevara-Lara (1) Keywords: Cactus pear; Maturation; Nopal; Plant growth regulator; Ripening; Tuna Abstract: To throw light on the expression of ripening-related genes in prickly pear (Opuntia sp.) fruits and on the possible role of the gaseous hormone ethylene in nonclimacteric fruit ripening, cDNA fragments that showed high homologies with 1-aminocyclopropane-1-carboxylate (ACC) synthase and ACC oxidase cDNAs from other plants were cloned and partially characterized. Thus, the corresponding genes were accordingly named opaccs-1 and opacco-1, after Opuntia ACC synthase-1 and Opuntia ACC oxidase-1, respectively. Southern analysis suggests the presence of at least one copy of both genes, as well as other related homologous sequences in the Opuntia genome. Northern analysis of the opaccs-1 gene shows an enhanced expression in ripening fruit tissues, whereas opacco-1 expression is highly induced in ripe tissues with respect to the green fruits and mature cladodes. These results are in agreement with an active metabolic role of ethylene during nonclimacteric prickly pear fruit ripening. This is the first report on the analysis at the molecular level of ripening-related genes of the Opuntia genus. Author Affiliation: (1) Depto. de Biotecnologia y Bioquimica, Unidad Irapuato, Centro de Investigacion y de Estudios Avanzados del IPN, Apdo. Postal, 629, Irapuato Gto., 36500, Mexico Article History: Registration Date: 23/12/2004

Byline: F. Delgado-Vargas (1), O. Paredes-Lopez (1) Keywords: Marigold; Tagetes erecta; Enzymatic extraction; Carotenoids; Lutein Abstract: The effect of enzymatic treatments using a commercial enzyme (Econase-cep at pH 5.0 and 0.1% w/w concentration) at different levels of dehydrated marigold meal (5, 10, 15 and 20% dry weight), to enhance carotenoid extraction, was evaluated. The AOAC method consisting of a simultaneous extraction and saponification by using hexane-ethanol-acetonetoluene (10:6:7:7 v/v) and metanolic KOH (40% w/v) was used to evaluate the carotenoid content. The measurement of carotenoids was also carried out in samples in which the water soluble compounds were previously eliminated (AOAC-[H.sub.2]O). Total carotenoids ranged from 11.4 to 17. 4 g/kg and 18 to 24.7 g/kg of control and treated marigold meal, respectively. Highest amount of carotenoids were noted when 5% level of treated meal was used. Author Affiliation: (1) Departmento de Biotecnologia y Bioquimica, Unidad Irapuato, Centro de Investigacion y de Estudios Avanzados del IPN, Apdo Postal 629, 36500, Irapuato, Gto, Mexico Article History: Registration Date: 26/05/2006 Received Date: 25/09/1996 Accepted Date: 05/11/1996

Impact of calcium hydroxide and extruder screw speed on physical and chemical properties of extruded blue maize meals is examined.

In this research it was attempted to overexpress the acidic subunit, from the 11S amaranth seed globulin termed amarantin, modified with antihypertensive peptides in Escherichia coli Rosetta (DE3) by manipulating some factors in batch fermenter such as growth medium composition, inducer (isopropyl β-D-thiogalactopyranoside [IPTG] or lactose), air flow, cultivation temperature, agitation speed and induction time. The possibility of using several minimal media and lactose as inducer to increase yields of the recombinant protein was investigated. Previous fermentations at flask level showed that two minimal culture media (A6 and A7) and 0.5% (w/v) lactose presented high yields of the engineered protein expression. Thus, the latter two media were tested at fermenter level, the lactose inducer, and different environmental conditions. Factors with significant effects were identified by Plackett-Burman design with center points and were adjusted at the level suggested and the yields of the recombinant protein were increased from 303.2 to 1,531 mg L(-1) in A6 and from 363.4 to 1,681 mg L(-1) in A7. Unlike some patents where the highest productivity was achieved at 24 h or afterwards, in this research the best productivity of the recombinant acidic subunit was attained at 4 and 6 h of induction using both media, respectively.

The aim of this investigation was to compare the liver and aorta changes in rats fed cholesterol-containing diets and the possible improvement when diets would be supplemented with frequently used raw vegetables. The phenolic compounds of three vegetables in methanol-water (1:1) fraction were characterized using electrospray ionization mass spectra (ESI-MS). Results showed that the content of polyphenols, flavonoids, quercetin, flavanols, tannins, and ascorbic acid varied for garlic and white and red onions ranging from 6.68 to 18.08 mg GAE/g DW, 490.4-701.0 μg CE/g DW, 281.2-1100.0 μg, 32.40-41.30 μg CE/g DW, 2.88-3.12 mg CE/g DW, 1.87-2.33 mg AA/g DW, 1388.2-1442.3 μg CGE/g DW, respectively. The radical scavenging capacities (μM TE/g DW) for the same investigated vegetables for ABTS, FRAP, CUPRAC, and DPPH assays ranged from 48.78 to 92.42, 9.41-28.56, 3.06-10.41, and 6.49-23.42, respectively. Good correlations were observed between the phenolic contents and the radical scavenging capacities of the vegetables. The interaction between BSA and quercetin, BSA and garlic and onions extracts was measured by 3-dimensional fluorescence (3D-FL) and Fourier transform infrared (FT-IR) spectroscopy. The highest polyphenol content was found in methanol/water fraction of onions and garlic; therefore, for the investigation of in vitro interactions with BSA only polyphenols of this fraction were used. For in vivo studies, 30 male Wistar rats were divided into 5 groups each of 6 and named Control, Chol, Chol/Garlic, Chol/OnionRed, and Chol/OnionWhite. During 6 weeks, the rats of all 5 groups were fed a basal diet (BD). The rats of the Control group were fed the BD only. The BD of the Chol group was supplemented with 10 g/kg of nonoxidized cholesterol (NOC). Each of the other three groups was supplemented with 10 g/kg of NOC and 500 mg of raw fresh garlic, 500 mg of raw fresh red onion, and 500 mg of raw fresh white onion on 1 kg of body weight for Chol/Garlic, Chol/OnionRed, and Chol/OnionWhite diet groups, respectively. In order to detect the changes in the liver and aorta, a histological procedure was applied, and the liver enzymes were determined and compared. It was found that the main changes vs the Control group were in the liver of rats fed the cholesterol-containing diet without vegetable supplementation. Significantly less histological changes in the liver and lower level of liver enzymes vs those of the Chol group were detected in rats of the Chol/Garlic group (P < 0.05). The interaction between the polyphenol extract of garlic and BSA in vitro showed its strong ability comparable with that of quercetin to quench the intrinsic fluorescence of BSA. In conclusion, all studied vegetables showed protective effects, but raw garlic supplemented with cholesterol-containing diets significantly prevented the aorta and liver damages of rats.

The polyphenolic composition of 62 wild and weedy Mexican bean collections from diverse origins, grouped by their seed coat color, was assessed. According to spectrophotometric analysis, the range of total phenols, condensed tannins, and total anthocyanins presented wide differences. Furthermore, the phenolic acid, flavonoid, and anthocyanin profiles were analyzed using HPLC. Ferulic was the main phenolic acid. Kaempferol and quercetin were the main flavonoids, and the isoflavones daidzein and coumestrol were found in only low levels in few collections. Delphinidin was the main anthocyanidin found, followed by petunidin, cyanidin, malvidin, pelargonidin, and peonidin. The wide variation observed in polyphenolic contents was more related to their genotype than to the color factor. These results show that some wild and weedy beans are good sources of phenolic compounds for use in breeding programs focused on nutrition and health.

Wild and cultivated maize, sorghum, rice, amaranth, soybean, and cassava were screened for variability in seed storage proteins. Total seed proteins, albumin (Alb-1 and Alb-2), globulin, alcohol-soluble (A1 and A2), and glutelin (G1 and G2) fractions were investigated by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The comparison was done by the obtained protein patterns and their relative amounts. Using quantitative analysis of the protein composition and the electrophoretic patterns, the relationships between total proteins and amount of individual proteins were determined. Electrophoretic patterns of extracted proteins from investigated samples showed that the main protein subunits were concentrated between 10 and 45 kDa. Variation was found in major fractions and minor bands. Electrophoretic patterns of the protein fractions are directly related to the genetic background of the protein and can be identified and used to certify the genetic makeup of wild, cultivated, or newly derived cereals and plants.