The preventing method of browning and γ-aminobutyric acid (GABA) contained in Luffa cylindrica Roem. cultivated in Okinawa

Luffa (Luffa cylindrica Roem.) is a popular vegetable in Okinawa, and it has abundant nutrients, including γ-aminobutyric acid (GABA). We focused on GABA content in luffa, taking into consideration registering it as foods with functional claims in Japan. Besides, when selling cut luffa and frozen cut luffa at supermarkets, they are supposed to get browned due to air exposure and other causes. In the present study, we developed the prevention method of browning cut luffa and frozen cut luffa using 0.5 %, 1.0 %, 2.0 %, and 4.0 % ascorbic acid solution. It was found that 55 L of 4.0 % ascorbic acid solution could be used for soaking of 70 kg cut luffa to prevent browning, but GABA content decreased in food processing of luffa in the factory. Besides, GABA content in luffa fruits was found not to change during storage for 07 days at room temperature after harvest.

Comparative Analysis of Flour Properties of Dioscorea alata Tuber And Its Utilization On Wet Noodle

Abstract— Dioscorea alata grown in many areas of the world has been intensively studied. However none of Indonesian cultivar has been intensively studied for their properties and its utilization in food industry. This research was aimed to compare the properties of purple Dioscorea alata’s flour produced using different methods and to study the effect of partly substituted wheat by purple Dioscorea alata’s flour on the characteristic of wet noodles. The research on the properties of purple Dioscorea alata’s flour was conducted using complete random design with treatment on the methods used to produce flour: control, steaming, soaking in 1% citric acid solution + steaming, blanching + soaking in 1% citric acid solution + steaming and blanching + soaking in 2% ascorbic acid solution + steaming.These 5 methods were repeated 4 times. The research on utilization of Dioscoreaalata’s flour on wet noodle was conducted using complete random design with 5 levels of treatment (0%, 10%, 20%, 30%, and 40% of Dioscorea alata’s flour) and 4 replications. The result showed that steaming the slices of tuber for 7 minutes prior to drying was an effective method to produce flour with strong natural color of purple. The concentration of Dioscorea alata’s flour significantly affects the elongation and texture of noodle (p<0.05). Except for its unpleasant grey color, wet noodle can be produced using up to 40% Dioscorea alata’s flour.

Histochemical examination on principal collagen fibers in periodontal ligaments of ascorbic acid-deficient ODS-od/od rats

In this study, we aimed to clarify the role of ascorbic acid in collagen synthesis in periodontal ligaments using osteogenic disorder Shionogi (ODS)/ShiJcl-od/od rats lacking L-gulonolactone oxidase. These rats cannot synthesize ascorbic acid in vivo. Eight-week-old ODS/ShiJcl-od/od male rats were administered ascorbic acid solution at a concentration of 200 mg/dL (control group, n = 6) or ascorbic acid solution at concentration of 0.3 mg/dL (insufficient group, n = 12). Six rats of the insufficient group were then given with ascorbic acid solution at concentration of 200 mg/dL for additional 3 weeks (rescued group, n = 6), and then, their mandibles were histochemically examined. Consequently, the insufficient group specimens were seen to possess fewer collagen fibers, and silver impregnation revealed numerous fine, reticular fiber-like fibrils branching off from collagen in the periodontal ligaments. In control group, faint immunoreactivities for matrix metalloproteinase (MMP)2 and cathepsin H were seen in the periphery of blood vessels and throughout the ligament, respectively. In contrast, in the insufficient group, intense MMP2-immunoreactivity was observed to be associated with collagen fibrils in the periodontal ligaments, and cathepsin H-immunopositivity was seen in ligamentous cells. The rescued group showed abundant collagen fibers filling the periodontal ligament space. Under transmission electron microscopy, ligamentous fibroblasts incorporated collagen fibrils into tubular endosomes/lysosomes while simultaneously synthesizing collagen fibril bundles. Thus, ascorbic acid insufficiency affected the immunolocalization of cathepsin H and MMP2; however, ligamentous fibroblasts appear to possess the potential to synthesize collagen fibers when supplied with ascorbic acid.

Method for quantification of antioxidant capacity of processed fruit juices exploring the formation of the Fe(II)/3-hydroxy-4-nitroso-2,7-naphthalenedisulfonic complex

The formation of the Fe(NRS)34− complex was used in a modified spectrophotometric method to quantify the total antioxidant capacity (TAC) of processed fruit juice samples. The procedure is based on the reduction of Fe(III) to Fe(II) in aqueous buffered solution (Tris; pH 8.0) containing the 3-hydroxy-4-nitroso-2,7-naphthalenedisulfonic acid (H2NRS). The absorbance values at 730 nm (A730 nm) of the Fe(NRS)34− complex obtained with juice samples were compared with A730 nm values obtained with a standard ascorbic acid solution and then subsequently used to quantify and express the TAC of the samples. Good positive relationship between TAC values in the analysed samples (grape, orange, passion fruit, cashew, peach, and strawberry) was found for both the Fe(NRS)34− complex method (proposed method) and ABTS•+ radical-free method (used as reference method). The TAC values obtained with Fe(NRS)34− and ABTS•+ also showed a positive correlation with the Folin–Ciocalteu index values. Fructose, glucose, BHT, and BHA did not interfere in the TAC quantification of the processed fruit juice samples with the proposed method. However, ascorbic acid (natural or added as additive, E300) and its derivatives (E301, E302, E303, E315, and E316) did interfere positively. As a 10-fold dilution is required and the absorbance measurements are performed at 730 nm, the proposed method was not subject to colour interference from the tested samples. The procedure suggested here is simple, easy to perform, reproducible, does not use organic solvents, and does not need expensive equipment.

Effect of pretreatments on mycotoxin profiles and levels in dried figs

The aim of this explorative study was to investigate how effective drying preservation methods are in reducing mycotoxin content in figs. Dried autochthonous varieties of white and dark figs (Petrovača Bijela and Šaraguja, respectively) were analysed for mycotoxins using an LC-MS/MS “dilute and shoot” method capable of determining 295 fungal and bacterial secondary metabolites. Before drying in a cabinet dryer the figs were preserved with 0.5 % citric acid solution or 0.5 % ascorbic acid solution or 0.3 % L-cysteine solution or 0.2 % chestnut extract solution or 0.15 % Echinacea extract solution by immersion. We found nine metabolites: aflatoxin B1 (AFB1), ochratoxin A, ochratoxin alpha, kojic acid, emodin, altenuene, alternariol methyl ether, brevianamide F, and tryptophol. The most efficient preserver was L-cysteine (15 % reduction), while ascorbic acid favoured mycotoxin production (158 % increase). However, all pretreatment solutions reduced AFB1, which is a major fig contaminant.

Análisis de la interacción entre radiaciones gamma y mms sobre la plántula de semillas de Triticale pretratadas con ácido ascórbico

The protective effect of the ascorbic acid against the physiological damage induced by gamma irradiation and MMS in Triticale caryopses was rested: caryopses were irradiated in absence of water, with water or in an ascorbic acid solution. No variation was detected in the survival following the different treatments. Germination speed was not affected by the different gamma irradiation doses. MMS concentrations and ascorbic acid were toxic.