Effect of nitric oxide on ethylene production in strawberry fruit during storage

Strawberry is a non-climacteric fruit, with low ethylene production rate after harvest. Its response to nitric oxide (NO), which can be released from sodium nitroprusside (SNP), was studied. We have examined the effect of 1.0, 5.0 and 10.0 μmol l⁻¹ SNP aqueous solution on ethylene production, respiration rate, 1-aminocyclopropane-1-carboxylic acid (ACC) content and the activities of ACC synthase and ACC oxidase in post-harvest strawberry (“Fengxiang”). The most remarkable effect was obtained with 5 μmol l⁻¹ SNP aqueous solution, which significantly inhibited ethylene production, respiration rate, the activity of ACC synthase and reduced the content of ACC, but did not significantly affect the activity of ACC oxidase. SNP at 10 μmol l⁻¹ harmed the fruits; 1 μmol l⁻¹ SNP was too low to significantly extend strawberry storage life. It was suggested that NO could decrease ethylene output, through inhibiting ACC synthase activity reducing ACC content.     

Effects of a pretreatment with nitric oxide on peach (<Emphasis Type="Italic">Prunus persica</Emphasis> L.) storage at room temperature

Peach is characterised by a rapid senescence associated with a high production of autocatalytic ethylene at the beginning of ripening, a fact which reduces markedly its postharvest shelf-life. The application of antisenescent compounds after harvesting has been assayed to solve this problem. One of the newest and more promising compounds is the free radical gas nitric oxide (NO). In this work, peaches of cv. ‘Rojo Rito’ were treated with 5 μL L⁻¹ of NO for 4 h, at 20 °C, and then stored at the same temperature for 14 days. Untreated fruits stored under the same conditions were used as control fruits in the experiment. Key physiological parameters of senescence (ethylene production and respiratory rate) and quality parameters (firmness, titrable acidity, total soluble solids and colour) were analysed. A particular emphasis was placed on the analysis of the oxidative status and the antioxidant capacity during storage and as a response to the NO treatment. The ethylene production and respiratory rate of fruits treated with NO were lower than those of control fruits. Treated fruits underwent a lesser loss of firmness during storage. The degree of disintegration of cell membranes, assessed as the percentage of electrolyte leakage, was also lower in fruits treated with NO. NO did not seem to affect lipid peroxidation or LOX activity, but it did affect PPO activity. The treatment with NO stimulated POX activity and, especially, SOD and CAT activities. It seems that total carotenoids and free ASC were not influenced by the pretreatment; however, the oxidised form of ASC, DHA, showed a slight increase. NO seemed to have a beneficial effect on the oxidation equilibrium and the antioxidant capacity of peach fruit. A delay in the initiation of the senescence of fruits treated with NO, that extended the postharvest shelf-life, was observed.     

Oil composition of coriander (<Emphasis Type="Italic">Coriandrum sativum </Emphasis>L.) fruit-seeds

Coriander (Coriandrum sativum L.) seeds were extracted with chloroform/methanol (2:1, v/v) and the amount of total lipid was 28.4% of seed weight. The major fatty acid was petroselinic acid (65.7% of the total fatty acid methyl esters) followed by linoleic acid. Chromatography on a silica column with solvent of increasing polarity yielded 93.0% neutral lipids, 4.14% glycolipids, and 1.57% phospholipids. Thin-layer chromatography on silica gel was used to obtain major neutral lipid subclasses. Fatty acid profile of neutral lipid subclasses, triacylglycerols, and sterol content were determined using gas-liquid chromatography. Six triacylglycerol molecular species were detected but one component (C54:3) corresponding to tripetroselinin, and/or dipetroselinoyl oleoyl glycerol comprised more than 50% of the total triacylglycerols. Sterol content was estimated to be at a high level (5186 µg g^-1 oil). Stigmasterol, #-sitosterol, ƕ-avenasterol, and campesterol were found to be the sterol markers. Phospholipid subclasses were separated by high-performance liquid chromatography on a silica column by gradient elution from isooctane/2-propanol (6:8, v/v) to isooctane/2-propanol/water (6:8:0.6, v/v/v) with detection at 205 nm. The major individual phospholipid subclasses were phosphatidylcholine followed by phosphatidylethanolamine, phosphatidylinositol, and phosphatidylserine.     

Antioxidant synergism between fruit juice and <Emphasis Type="Italic">α</Emphasis>-tocopherol. A comparison between high phenolic black chokeberry (<Emphasis Type="Italic">Aronia melanocarpa</Emphasis>) and high ascorbic blackcurrant (<Emphasis Type="Italic">Ribes nigrum</Emphasis>)

Black chokeberry juice (Aronia melanocarpa, Elliot), blackcurrant juice (Ribes nigrum, Ben Lomond) and α-tocopherol were found to protect phosphatidyl choline against oxidation in a peroxidating liposome system as evidenced by lag phases for formation of conjugated dienes. When present together, black chokeberry juice and α-tocopherol showed a clear synergistic effect on the length of the lag phase, while effects of blackcurrant juice and α-tocopherol were additive. The concentration of total phenolics in black chokeberry juice was six times higher than in blackcurrant juice (gallic acid equivalents). Ascorbic acid corresponded to 1% of total phenolics in black chokeberry juice and 10% in blackcurrant juice. Based on the length of the lag phase, the phenolics present in black chokeberry were on an average, twice efficient as scavengers of lipid peroxyl radicals as phenolics in blackcurrant. Black chokeberry was by HPLC analysis of peroxidating liposomes, in contrast to blackcurrant, found to protect α-tocopherol efficiently against oxidation to the end of the lag phase. The phenolics present in black chokeberry juice were concluded to be more efficient in regenerating or protecting α-tocopherol than ascorbic acid or the phenolics in blackcurrant. As for the phenolics, this was further evidenced by ranking of their radical scavenging activity as studied by ESR-spectroscopy.     

<Emphasis Type="Italic">In vitro</Emphasis> characterization study of <Emphasis Type="Italic">Bacillus mojavensis</Emphasis> KJS-3 for a potential probiotic

The identification and characterization of Bacillus mojavensis KJS-3 was performed by in vitro tests. A 16S rDNA sequence and phylogenetic tree demonstrated that this isolate belongs to the B. mojavensis group. B. mojavensis KJS-3 supplies nutrients by synthesizing several vitamins. B. mojavensis KJS-3 produces α-amylase and protease. B. mojavensis KJS-3 is cultured well under aerobic conditions without gas production. B. mojavensis KJS-3 allows for assimilation of cholesterol and bile salt hydrolase activity. Finally, adhesion experiments using Caco-2 cells revealed that the adherence of B. mojavensis KJS-3 to Caco-2 cells was approximately 51.2±8.14%.     

Volatile flavor composition of <Emphasis Type="Italic">gamguk</Emphasis> (<Emphasis Type="Italic">Chrysanthemum indicum</Emphasis>) flower essential oils

The volatile composition of the essential oil from fresh gamguk (Chrysanthemum indicum) flowers was investigated. The volatile constituents were extracted by the hydro distillation method. Volatile compositional changes of gamguk prepared via different drying methods (shade- and freeze-drying methods) were also determined. Total 36, 63, and 55 volatiles constituents were confirmed in the essential oil from fresh and shade-, and freeze-dried flowers. Ketones were predominant in the volatiles of gamguk flowers (%): fresh, 43.8; shade dried, 30.3; and freeze dried, 36.1. Camphor was the most abundant volatile component in all samples, and the content of borneol was also remarkable. The content of camphor was higher in fresh sample than those of dried samples while borneol concentration was significantly increased in the dried samples.     

Assessing the digestion of a genetically modified tomato (<Emphasis Type="Italic">Solanum lycopersicum</Emphasis>) R8 DNA in simulated gastric fluid using event-specific real-time PCR

There are numerous studies that have demonstrated the digestion of plant DNA in the gastrointestinal (GI) tracts of various animal species. In this study, we investigate the process of DNA degradation in the GI tract using simulated gastric fluid treatment and quantitative PCR approach. Event-specific SYBR Green and TaqMan real-time PCR methods were developed in the present study for measuring the degradation of GM tomato R8 DNA. The selectivity, sensitivity, accuracy, and precision of real-time PCR detection methods were feasible for detection and quantification purposes. The results of real-time PCR analysis revealed that approximately 99.98% of an endogenous gene was degraded and could not be amplified after 180-min simulated gastric fluid treatment. The rapid acid hydrolysis of tomato fruit DNA in the SGF suggests that only less than 1% of genetically modified tomato fruit DNA could survive through the human digestive system.     

Purification of <Emphasis Type="Italic">S</Emphasis>-Alk(en)yl alka/enethiosulfinates of garlic (<Emphasis Type="Italic">Allium sativum</Emphasis> L.) by using recycling preparative HPLC

S-Alk(en)yl alka/enethiosulfinates formed in crushed garlic were purified by using recycling preparative HPLC. Allyl 2-propenethiosulfinate and methyl methanethiosulfinate were effective separated because no other thiosulfinates were coeluted with them. Allyl methanethiosulfinate and methyl 2-propenethiosulfinate, trans-1-propenyl methanethiosulfinate and methyl trans-1-propenethiosulfinate, (cis)- and (trans)-1-propenyl 2-propenethiosulfinate were eluted as 1 peak, respectively, and further separated by using additional kinds of column. Since the quantity of trans-1-propenyl trans-1-propenethiosulfinate (PPTHS) was small in garlic, PPTHS was isolated from a mixture of blanched onion homogenate and garlic alliinase and purified. Purified thiosulfinates can be employed for the study of antimicrobial activity, flavor, and greening of garlic.     

Effects of processing and storage on the stability of free and esterified carotenoids of red peppers (<Emphasis Type="Italic">Capsicum annuum</Emphasis> L.) and hot chilli peppers (<Emphasis Type="Italic">Capsicum frutescens</Emphasis> L.)

The stability of non-esterified carotenoids and carotenoid esters in paprika and chilli powder as affected by various processing treatments and storage conditions were studied. For this purpose, freshly harvested chilli and paprika pods were minced, immediately heated at 80, 90 and 100 °C for 5 and 10 min, respectively, and lyophilised. Alternatively, thermal treatment prior to mincing was applied. Processing resulted in a 25–34% loss of the initial carotenoid contents in chilli and 20–53% in paprika. Degradation of individual non-esterified carotenoids, mono- and diesters was monitored, generally showing an increased processing stability of mono- and diesters compared to their non-esterified counterparts. Capsanthin, capsorubin, zeaxanthin and β-cryptoxanthin mono- and diesters esterified with saturated fatty acids displayed similar stabilities, whereas susceptibility of the non-esterified pigments to degradation differed considerably. During storage over 4 months at ambient temperature pigment contents dropped by 16.7 and 9.6% in chilli and by 39.7 and 38.8% in paprika powders with and without illumination, respectively.     

Fruit quality of Italian pomegranate (<Emphasis Type="Italic">Punica granatum</Emphasis> L.) autochthonous varieties

Pomegranate is getting an increasing attention for its health-promoting effects. Collection and characterization of plants of local sources has been performed, and five accessions have been propagated and cultivated in a collection field for extra situ investigations. Accessions differ for pomological traits and chemical composition. Three of them, MG1, MG2, and MG3, belong to typology with low-medium acidity and high sugar content, while the other two, Tordimonte A and B, belong to typology with high acidity. In the juice and in the peels’ extract of Tordimonte A accession a high level of punicalin has been found through chromatographic determinations, while the presence of punicalagin was found in the juice of accession MG1. The accessions MG1, MG2, and MG3 seem particularly suitable for direct commercialization of fruits due to the fruit traits and quality (sweet varieties), while Tordimonte A and B could be valuable for juice processing (sour varieties).     

Production of malic and succinic acids by sugar-tolerant yeast <Emphasis Type="Italic">Zygosaccharomyces rouxii</Emphasis>

Zygosaccharomyces rouxii V19 was grown in YPG medium (yeast extract, 0.5%, peptone, 1.0%, glucose, 10%). Fermented broth was purified through a series of ion-exchange columns and ODS column and the purified sample was TMS-esterified. Malic and succinic acids were identified with GC-MS analysis. The yeast was cultivated under various cultural conditions and quantitative determination of the organic acids was carried out with HPLC on Shodex column. Glucose concentration of 30%, initial pH 5.0, and 25 °C incubation temperature were the optimum conditions. Inclusion of glutamic, malic, and succinic acid precursors in the medium increased the production of malic acid. On the other hand, only addition of malic acid enhanced the production of succinic acid. Maximum amount of malic acid produced was 74.9 g/L (32.8% yield, based on glucose consumption) in the medium with 0.5% glutamic acid supplement, and that of succinic acid was 7.7 g/L (8.1% yield) when 0.3% malic acid was added in the medium.     

Dark chocolates supplemented with <Emphasis Type="Italic">Lactobacillus</Emphasis> strains

Dark chocolate masses and chocolates were supplemented with viable cells of two bacterial strains Lactobacillus caseii and Lactobacillus paracasei with potential probiotic properties, which were lyophilized in milk. Total number of live bacteria in the lyophilizate was 7.9×10⁹ cfu/g. Sucrose or isomalt and aspartame were used as bulking substances and sweeteners. Sensory attributes of these chocolates were not different from that of traditional chocolates. Calorie value of sucrose-free chocolate was lower by approximately 11.1–14.6% (dependent on their formulation) relative to chocolate sweetened with sucrose. Chocolate, which contains isomalt and aspartame can be consumed by diabetics. Numbers of live L. casei and L. paracasei cells in the examined batches of chocolate were very high and approached 10⁶–10⁷ cfu/g after 12 months of keeping at 4 and 18 °C. Neither the texture nor the total and volatile acidity of chocolate masses were changed by addition of the lyophilized preparation of Lactobacillus cells. Casson yield values of dark sucrose-free chocolate masses supplemented with this lyophilizate were decreased by approximately 3–55% (dependently on fat contents in these masses) as compared to that of analogous chocolate masses sweetened with sucrose.     

Characterization of moisture content and specific gravity of branchwood and stemwood of <Emphasis Type="Italic">Aningeria robusta</Emphasis> and <Emphasis Type="Italic">Terminalia ivorensis</Emphasis>

Aningeria robusta and Terminalia ivorensis of diameters ranging from 10 cm to 25 cm were examined. The following results were obtained: The overall (sapwood and heartwood combined) moisture contents of the branchwood of both Aningeria robusta and Terminalia ivorensis were significantly greater than those of their corresponding stemwood, with the branchwood of Terminalia ivorensis being the highest. It was also observed that the overall specific gravity of the branchwoods of both species was higher than that of the corresponding stemwood, with the branchwood of Aningeria robusta exhibiting the highest specific gravity. Detailed analyses of moisture content distribution and specific gravity of the heartwood and sapwood of Aningeria robusta and Terminalia ivorensis are also presented.     

Disinfection effect and its mechanism of electrolyzed oxidizing water on spores of <Emphasis Type="Italic">Bacillus subtilis</Emphasis> var. <Emphasis Type="Italic">niger</Emphasis>

A study was carried out on the disinfection efficiency of electrolyzed oxidizing water (EOW) on spores of Bacillus subtilis var. niger. The results showed a remarkable fungicidal rate of 100% after 20 min duration of 191 mg/L active available chlorine (ACC). The disinfection effect was improved with increased ACC or prolonged disinfection time, while organic interferents exerted a strong concentration-dependent inhibition against the disinfection. The disinfection mechanism was also investigated at bio-molecular level. EOW decreased dehydrogenase activity, intensified membrane permeability, elevated suspension conductivity, and caused leakage of intracellular K⁺, proteins, and DNA, indicating a damage of cell walls and membranes. Effects of EOW on microbiological ultra-structures were also verified by transmission electronic microscopy (TEM) images, showing that EOW destroyed protective barriers of the microbe and imposed some damages upon the nucleus area.     

Optimization of carotenoids by <Emphasis Type="Italic">Rhodotorula glutinis</Emphasis>

Response surface methodology was applied to maximize the yield and productivity of carotenoids by Rhodotorula glutinis strain 1151 using supplemented tomato waste based medium. Higher concentration of tomato waste extract and yeast extract favored the production of carotenoids. In contrast to carotenogenesis higher concentration of yeast extract negatively affected the formation of biomass whereas higher amount of glucose in the medium favored biomass indicating that carotenogenesis is not correlated to biomass. The optimal concentration of medium components for maximum total carotenoids and corresponding biomass production as obtained from model were calculated to be as 660 mL/L, 1.5, 4.5, 7.4, and 10 g/L for tomato extract, malt extract, yeast extract, peptone, and glucose, respectively.     

Fractioned High Pressure Extraction of Anthocyanins from Elderberry (<Emphasis Type="Italic">Sambucus nigra</Emphasis> L.) Pomace

Fractionated high pressure extractions from dry and in natura elderberry pomace were performed in order to obtain anthocyanin rich extracts. Experiments were carried out using CO₂ supercritical fluid extraction followed by enhanced solvent extraction (ESE) with CO₂/EtOH–H₂O mixtures (1–100%, v/v), to obtain anthocyanin rich fractions in the second step, at 313 K and ~20 MPa. Higher extract yields, anthocyanin contents and antioxidant activities occurred by the presence of water, both in the raw material and in the solvent mixture. The CO₂ dissolved in the ESE solvent mixture favored either anthocyanin contents or antioxidant activities, which were not directly related. Comparing to the literature data for elderberries and grapes, these fractions had higher anthocyanins contents. From these results, an added economical value to this agroindustrial residue is proposed, using solvents and techniques “generally regarded as safe” in the food and pharmaceutical industries.     

Phytochemical and biological investigation of <Emphasis Type="Italic">Stevia rebaudiana</Emphasis> Bertoni; 1-labdane-type diterpene

Five labdane diterpenoids, austroinulin, iso-austroinulin, sterebin E, sterebin E acetate, and sterebin A acetate, along with hydrocarbons, aliphatic alcohols, β-amyrin, β-sitosterol and stigmasterol were isolated from the chloroform soluble fraction of the methanol extract of Stevia rebaudiana leaves. Chlorogenic and caffeic acids were isolated from the EtOAc fraction. All the isolated compounds were identified using spectral tools. The chloroform and methanol extracts proved significant anti-inflammatory effect and caused marked inhibition of carrageenan-induced paw oedema in rats.     

Aromatic characterization and enological potential of 21 minor varieties (<Emphasis Type="Italic">Vitis vinifera</Emphasis> L.)

The homogenization of international wine market led to a gradual impoverishment of the genetic pool. In fact, in several Spanish Quality Demarcations, the most frequent international varieties are replacing the local ones. As a result, minor varieties, perfectly adapted to the local environmental conditions, are nowadays at risk of extinction. The study of minor varieties could provide useful inputs to satisfy the demand for new and interesting wine products. This work aims at filling a gap in the existing literature, focusing on the aromatic potential of minor varieties. Here, the study of glycosidic volatile compounds and the evaluation of the influence of several variables on aroma composition were considered. Fifty-one glycosidic compounds were identified and quantified. The results revealed differences for glycosidic compounds according to cultivars, berry color, clone and sample origin. The inclusion or not of the cultivars in Quality Demarcation was also discussed. Moreover, the synthesis of some compounds involved in these differentiations seems to have a genetic component. The characterization of aromatic potential of several minor varieties, achieved for the first time, revealed that some of these (Argamusa, Quigat, Pampolat girat, Excursach, Gorgollasssa or Mandón) could represent an excellent option for winemaking and commercial offer diversification strategies, besides being important for these cultivars conservation.