Enantioselective Degradation of (2RS,3RS)‐Paclobutrazol in Peach and Mandarin Under Field Conditions

In this study we investigated the enantioselective degradation of (2RS,3RS)‐paclobutrazol in peach and mandarin fruits under field conditions after foliar treatment at 500 mg active ingredient/L using a Lux Cellulose‐1 chiral column on a reverse‐phase liquid chromatography–tandem mass spectrometry system. Degradations of paclobutrazol in both fruits followed first‐order kinetics, with half‐lives of about 9 days. Initial deposits were 1.63 mg/kg on peach and 1.99 mg/kg on mandarin; terminal concentrations were lower than 0.05 mg/kg, which was acceptable in most cases. As anticipated, paclobutrazol levels in peels of mature mandarin were about 6.3 times higher than in pulp, indicating the potential risk of peel consumption. We also observed that paclobutrazol degradation in mature mandarin was relatively slow, indicating it might not be efficient enough to hold mandarin fruits on trees for lowering paclobutrazol concentrations. Significant enantioselectivity was observed: the (2R,3R)‐enantiomer was preferentially degraded in mandarin (whole fruit, peels, and pulp) but enriched in peach. Because of its more rapid degradation in mandarin and the lower levels observed in pulp compared with peels, potential endocrine‐related side effects due to the (2R,3R)‐enantiomer pose less of a risk in mandarin than in peach. Chirality 26:400–404, 2014. © 2014 Wiley Periodicals, Inc.     

Ion-pair high-performance liquid chromatographic assay method for the assessment of clarithromycin stability in aqueous solution and in gastric juice

A simple and selective ion-pair HPLC method has been developed for the analysis of clarithromycin in aqueous solutions and in gastric juice. A Hypersil ODS 5-μm (150 × 4.6 mm I.D.) column was used with a mobile phase consisting of acetonitrile-aqueous 0.05 M phosphate buffer (pH 4.6) containing 5 mM 1-octanesulphonic acid (50:50, v/v). The column temperature was 50°C and detection was by UV absorption (210 nm). The limits of detection of 50-μl samples were 0.4 μg/ml (aqueous) and 0.78 μg/ml (0.5 ml gastric juice) or better. The assay was linear in the range of 1.56 to 100 μg/ml with r² values greater than 0.99. The recovery from the gastric juice samples was 98.5±2.9%. The method was applied successfully to determine the stability of clarithromycin in 0.01 M HCl and gastric juice.     

3',5'-Di-C-beta-glucopyranosylphloretin, a flavonoid characteristic of the genus Fortunella

Dihydrochalcone derivative, 3',5'-di-C-beta-glucopyranosylphloretin (1), is present in the genus Fortunella, (F. crassifolia, F. japonica, F. margarita, F. polyandra and F. hindsii). These species accumulate a large quantity of 1 in their fruits (peel, 6.5-15.2 mg/g in dry wt; juice sac, 1.5-10.5 mg/g) and in their leaves (21.3-60.2 mg/g). Twenty-seven Tanaka's Citrus species examined lack 1, but C. madurensis and C. halimii contain 1 in large quantities in their peels (25.1 and 33.6 mg/g) and juice sacs (4.1 and 4.2 mg/g). Poncirus species do not contain 1. Fortunella-citrus hybrids, the Orangequat [C. unshiuxF. crassifolia], the Thomasville citrangequat [Fortunella sp.x(C. sinensisxPoncirus trifoliata)], and seven hybrid progenies [F. margaritaxC. junos], contain large amounts of 1 in their peels (17.0-7.9 mg/g) and juice sacs (2.0-9.9 mg/g). These facts suggest that accumulation of 1 is a generic trait of the genus Fortunella and that the inheritance of the trait among the intergeneric hybrids is controlled by a dominant allele. Thus C. madurensis and C. halimii are thought to originate from natural hybrids between the genera Citrus and Fortunella. Phloridzin, which has the same aglycon as 1, was not detected in the citrus plants examined.     

Determination of diclazuril, toltrazuril and its two metabolites in poultry tissues and eggs by gel permeation chromatography-liquid chromatography-tandem mass spectrometry

A new procedure has been described for the extraction of diclazuril (DIZ), toltrazuril (TOZ) and its two main metabolites toltrazuril sulphoxide (TZSO) and toltrazuril sulphone (TZS) from poultry tissues and eggs, using gel permeation chromatography (GPC). The analytes and the deuterated internal standard were extracted from the samples with ethyl acetate. The analytes were measured by LC coupled to an electrospray ionization tandem mass spectrometer operating in the negative ion mode. Excellent linear dynamic range was observed from 1 to 500 μg/L with the correlation coefficients (R(2)) better than 0.99 for all analytes. The method LOQ of the four analytes in real samples was 1.2 μg/kg for DIZ and TOZ, and 1.8 μg/kg for TZSO and TZS. These values are far lower than the maximum residue limits (MRLs) established by several control authorities. The developed method was accurate with overall recoveries in four matrices.     

超低氧处理对贮藏期间甜橙果实挥发性物质含量的影响

本文主要探讨甜橙［(Citrus sinensis (L.) Osb.］果实在短期超低氧贮藏条件下,果皮和果汁中乙醇和乙醛等挥发性物质的含量,以及它们在不同贮藏温度和货架存放期间的变化和对果实风味品质的影响。在普通冷藏条件下,随着贮藏期的延长,甜橙果实中挥发性物质的含量虽呈上升趋势,但超低氧贮藏更明显地刺激果实中乙醇和乙醛含量的迅速增加。甜橙果实在0.3% O2的超低氧条件下贮藏30 d,果皮中乙醇的含量为519.8　μg/kg,果汁中达1547.1　μg/kg,比普通冷藏的果实高83倍,乙醛的含量较对照果实高6～7倍。低氧处理对果实可溶性固形物,可滴定酸和pH值的影响不大。甜橙果汁中乙醇含量在1000 μg/kg以下时果实的风味品质仍在正常范围之内。结果表明对甜橙果实进行短期（<20 d）的超低氧处理是可行的。     

Cellulose, hemicelluloses, lignin and ash content of some organic materials and their suitability for use as paper pulp supplements

Freshwater algal biomass and orange and lemon peels were assessed as tissue paper pulp supplements. Cellulose and hemicellulose contents of algal biomass were 7.1% and 16.3%, respectively, whereas for citrus peels cellulose content ranged from 12.7% to 13.6% and hemicellulose from 5.3% to 6.1%. For all materials, lignin and ash content was 2% or lower, rendering them suitable for use as paper pulp supplements. The addition of algal biomass to paper pulp increased its mechanical strength significantly. However, brightness was adversely affected by chlorophyll. The addition of citrus peels in paper pulp had no effect on breaking length, increased bursting strength and decreased tearing resistance. Brightness was negatively affected at proportions of 10%, because citrus peel particles behave as coloured pigments. The cost of both materials is about 45% lower than that of conventional pulp, resulting in a 0.9-4.5% reduction in final paper price upon their addition to the pulp.     

Occurrence of fumonisins (B<Subscript>1</Subscript>, B<Subscript>2</Subscript>, B<Subscript>3</Subscript>) in maize-based food and feed samples from Indonesia

A survey to evaluate the contamination level of total fumonisins in maize-based foodstuffs, maize and feed from Indonesia is described. The analyses were carried out by enzyme-linked immunosorbent assay (ELISA). Samples were collected from local retail stores around Yogyakarta, Indonesia between February and May 2001. The 101 samples were classified into six categories, i.e. industrially-produced food (n=24), products of small food manufacturers (n=17), maize flour (n=4), maize for food (n=9), maize for feed (n17), and formulated feed (n30). Control of the method showed that the detection limit was 8.7 μg/kg and repeatability is shown by relative standard deviation (RSD) of analyses of contaminated maize (n=5) of 10 %. Results of analyses indicate that 80 samples analysed were contaminated over a large range from 10.0-3307 pg/kg, and the concentration of fumonisins depended on the type of sample. Of four samples of maize flour, none were contaminated (below detection limit). Of 24 samples of industrially produced food, 14 were contaminated in the range 22.8 - 105 μg/kg and 18 of 19 food samples from small manufacturers were contaminated ranging from 12.9 to 234 μg/kg. The highest contamination was observed in maize samples: six of ten samples of maize for food were contaminated between 68.0 - 2471 μg/kg and 16 of 17 samples for feed contained fumonisins over a large range from 17.6 to 3306 μg/kg.     

Determination of isometamidium residues in animal-derived foods by liquid chromatography-tandem mass spectrometry

In this paper, a new determination method for isometamidium residues in animal-derived foods was developed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Isometamidium residues in bovine tissues and milk were extracted with the mixed solution of acetonitrile and 0.25 mol/L of ammonium formate-methanol (v/v, 1:1), concentrated and degreased, and determined by LC-MS/MS with quantification by external standard method. The results showed that the peak area of chromatogram was linearly related to the concentration of isometamidium in the range of 1-100 μg/L, and the limits of detection (LOD) and quantification (LOQ) were 0.05 μg/kg and 5 μg/kg, respectively. The average recoveries of spiked samples were in the range of 73.8-93.9% with relative standard deviations ranged from 2.3% to 7.5%. This method is simple, accurate and suitable for the identification and quantification for isometamidium in animal-derived foods.     

Phenolic compounds in peach (Prunus persica) cultivars at harvest and during fruit maturation

Six peach and six nectarine cultivars were evaluated for the phenolic content in their pulp and peel tissues. Chlorogenic acid, catechin, epicatechin, rutin and cyanidin-3-glucoside were detected as the main phenolic compounds of ripened fruits. The concentration was always higher in peel tissue, with average values ranging from 1 to 8 mg g⁻¹ dry weight (DW) depending on cultivar. Of the tested varieties, the white-flesh nectarine 'Silver Rome' emerged as the cultivar with the highest amount of total phenolics. Phenolic compounds were also profiled during fruit growth and ripening in the yellow nectarine cv. 'Stark Red Gold', which showed a decreasing concentration during fruit development in both peel and pulp tissues. Average amounts of total phenolics were approximately 25 mg g⁻¹ DW 60 days after full bloom and decreased to 3 mg g⁻¹ DW at ripening in pulp tissue. Differences among peel and pulp composition show the different dietetic and antioxidant potential of fruits consumed unpeeled and peeled.     

A survey of fumonisins (B1, B2, B3) in Indonesian corn-based food and feed samples

In this paper a survey is described for determination of contamination level of fumonisins (B¹, B², B³) in Indonesian cornbased feed and food samples. The survey was conducted from February to May 2001. Foodstuffs, which are consumed directly such as snacks and other products, were investigated for fumonisin contamination. Of 105 food and feed samples purchased from local retail stores and local poultry shops around Yogyakarta, Java, Indonesia were analyzed using ELISA. Results indicate that 74.3% of samples analyzed were contaminated in a large range of 10.0 – 3307 μg/kg, and the concentration of fumonisins depends on the type of samples. Detection limit of the method used was 9 μg/kg.From eight food samples of maize flour, and corn-based beverages and cereals, none was contaminated (below detection limit). For food samples of industrial products (19 samples), 13 were contaminated in the range of 22.8 – 105 μg/kg and 19 of 20 samples from home made products were contaminated between 12.9 – 234 μg/kg. The food samples contaminated in highest level occurred in corn. Of ten samples, 6 were contaminated from 68.0 – 2471 μg/kg. For feed samples, 17 corn samples were evaluated. Of those samples, 16 contained in a large range of 17.6 – 3306 μg/kg.     

Comparative study on application of T.lanuginosus SSBP xylanase and commercial xylanase on biobleaching of non wood pulps

Biobleaching of three non wood kraft pulps (bagasse, rice straw and wheat straw) by Thermomyces lanuginosus SSBP xylanase and commercial xylanase (cartazyme sandoz), was studied in order to investigate their potential and effect on their various properties (reduction sugars, chlorine dioxide, kappa number, brightness and chromophores). In generally, xylanases released chromophores and reducing sugars and decreased kappa number of pulps. These samples gained over six brightness points over controls. Biobleaching of rice straw pulp with xylanase cartazyme (Sandoz) produced chlorine dioxide savings of up to 25% or 3.5-4 kg chlorine dioxide/ton pulp.     

Simultaneous determination of ten aminoglycoside antibiotics in aquatic feeds by high-performance liquid chromatography quadrupole-orbitrap mass spectrometry with pass-through cleanup

A simple and sensitive method has been established based on pass-through cleanup and high-performance liquid chromatography quadrupole-orbitrap mass spectrometry (HPLC-Q/Orbitrap MS) for the simultaneous determination of ten aminoglycosides (AGs) in aquatic feeds. The extraction solution and cleanup procedure had been optimized, and good sensitivity, accuracy, and precision were obtained. The calibration curves of AGs were linearity (R² > 0.99) in the range of 2.0 to 200 μg/L (or 5.0 to 500 μg/L). The limits of detection of AGs were between 10 and 25 μg/kg. The recoveries of AGs ranged from 74.9% to 94.3%, and the intraday and interday relative standard deviations were less than 15%. Finally, this method was successfully applied to determine ten AGs in 30 aquatic feed samples. It might be the first time to use pass-through cleanup approach combined with HPLC-Q/Orbitrap MS method for AGs determination in aquatic feed samples.     

Dietary fibre components and pectin chemical features of peels during ripening in banana and plantain varieties

The effects of the ripeness stage of banana (Musa AAA) and plantain (Musa AAB) peels on neutral detergent fibre, acid detergent fibre, cellulose, hemicelluloses, lignin, pectin contents, and pectin chemical features were studied. Plantain peels contained a higher amount of lignin but had a lower hemicellulose content than banana peels. A sequential extraction of pectins showed that acid extraction was the most efficient to isolate banana peel pectins, whereas an ammonium oxalate extraction was more appropriate for plantain peels. In all the stages of maturation, the pectin content in banana peels was higher compared to plantain peels. Moreover, the galacturonic acid and methoxy group contents in banana peels were higher than in plantain peels. The average molecular weights of the extracted pectins were in the range of 132.6-573.8 kDa and were not dependant on peel variety, while the stage of maturation did not affect the dietary fibre yields and the composition in pectic polysaccharides in a consistent manner. This study has showed that banana peels are a potential source of dietary fibres and pectins.     

Apple juice inhibits human low density lipoprotein oxidation.

Dietary phenolic compounds, ubiquitous in vegetables and fruits and their juices possess antioxidant activity that may have beneficial effects on human health. The phenolic composition of six commercial apple juices, and of the peel (RP), flesh (RF) and whole fresh Red Delicious apples (RW), was determined by high performance liquid chromatography (HPLC), and total phenols were determined by the Folin-Ciocalteau method. HPLC analysis identified and quantified several classes of phenolic compounds: cinnamates, anthocyanins, flavan-3-ols and flavonols. Phloridzin and hydroxy methyl furfural were also identified. The profile of phenolic compounds varied among the juices. The range of concentrations as a percentage of total phenolic concentration was: hydroxy methyl furfural, 4-30%; phloridzin, 22-36%; cinnamates, 25-36%; anthocyanins, n.d.; flavan-3-ols, 8-27%; flavonols, 2-10%. The phenolic profile of the Red Delicious apple extracts differed from those of the juices. The range of concentrations of phenolic classes in fresh apple extracts was: hydroxy methyl furfural, n.d.; phloridzin, 11-17%; cinnamates, 3-27%; anthocyanins, n.d.-42%; flavan-3-ols, 31-54%; flavonols, 1-10%. The ability of compounds in apple juices and extracts from fresh apple to protect LDL was assessed using an in vitro copper catalyzed human LDL oxidation system. The extent of LDL oxidation was determined as hexanal production using static headspace gas chromatography. The apple juices and extracts, tested at 5 microM gallic acid equivalents (GAE), all inhibited LDL oxidation. The inhibition by the juices ranged from 9 to 34%, and inhibition by RF, RW and RP was 21, 34 and 38%, respectively. Regression analyses revealed no significant correlation between antioxidant activity and either total phenolic concentration or any specific class of phenolics. Although the specific components in the apple juices and extracts that contributed to antioxidant activity have yet to be identified, this study found that both fresh apple and commercial apple juices inhibited copper-catalyzed LDL oxidation. The in vitro antioxidant activity of apples support the inclusion of this fruit and its juice in a healthy human diet.     

Carbohydrate-Free Peach (Prunus persica) and Plum (Prunus domestica) Juice Affects Fecal Microbial Ecology in an Obese Animal Model

Background

Growing evidence shows the potential of nutritional interventions to treat obesity but most investigations have utilized non-digestible carbohydrates only. Peach and plum contain high amounts of polyphenols, compounds with demonstrated anti-obesity effects. The underlying process of successfully treating obesity using polyphenols may involve an alteration of the intestinal microbiota. However, this phenomenon is not well understood.

Methodology/Principal Findings

Obese Zucker rats were assigned to three groups (peach, plum, and control, n = 10 each), wild-type group was named lean (n = 10). Carbohydrates in the fruit juices were eliminated using enzymatic hydrolysis. Fecal samples were obtained after 11 weeks of fruit or control juice administration. Real-time PCR and 454-pyrosequencing were used to evaluate changes in fecal microbiota. Over 1,500 different Operational Taxonomic Units at 97% similarity were detected in all rats. Several bacterial groups (e.g. Lactobacillus and members of Ruminococcacea) were found to be more abundant in the peach but especially in the plum group (plum juice contained 3 times more total polyphenolics compared to peach juice). Principal coordinate analysis based on Unifrac-based unweighted distance matrices revealed a distinct separation between the microbiota of control and treatment groups. These changes in fecal microbiota occurred simultaneously with differences in fecal short-chain acids concentrations between the control and treatment groups as well as a significant decrease in body weight in the plum group.

Conclusions

This study suggests that consumption of carbohydrate-free peach and plum juice has the potential to modify fecal microbial ecology in an obese animal model. The separate contribution of polyphenols and non-polyphenols compounds (vitamins and minerals) to the observed changes is unknown.     

Citrinin in fruit juices

Despite the wide distribution of citrinin-producingPenicillium spp. there are only rare reports about the occurence of this mycotoxin in foodstuffs. Particularly, the discrepancy between the common detection of the applerotting fungusP expansum and the complete lack of data about the occurrence of citrinin in apple-based foods is noteworthy. Based on an indirect enzyme immunoassay (EIA) a study was performed aiming at the sensitive detection of citrinin in apple and other fruit juices. The direct analysis of diluted apple juices by the EIA failed due to pronounced sample matrix effects. Though these problems could be resolved by the extraction of artificially contaminated apple juice with dichloromethane, a poor recovery rate (20–30%) for citrinin was observed. Astonishingly, similar results (mean recovery of 29.9%) were received when doted apple juices were directly purified on immunoaffinity columns despite the minimal sample treatment associated with this method. For the detection of citrinin in tomatoe juices samples were purified with a liquid-liquid partition step. Again, the mean recovery rate was very low (32.0%). Analyzing 55 fruit and vegetable juices purchased in local retail stores only traces of citrinin (maximum 0.2 μg/L) could be detected in the samples.     

Field dissipation of the pyrethroid insecticide/acaricide biphenthrin on the foliage of peach trees, in the peel and pulp of peaches, and in tomatoes

Biphenthrin was applied in the field to peach trees and tomato plants at rates of 2 and 4 g of biphenthrin a.i., 100 e.c. Talstar (Anon., 1983; FMC, USA)/100 litres of water. During the experimental period, three to four applications were made to peach trees and four to tomato plants at 14-day intervals. Samples from peach foliage, peaches and tomatoes were collected at set post-application dates and analysed for biphenthrin residues by GLC.
The foliar residues of biphenthrin ranged from 65±1 (maximum to 25± 1 (minimum) ng/cm² and from 101±52 (maximum) to 35±7 (minimum) ng/cm² at the low and high rates of application, respectively. The residues of biphenthrin in the peach fruit peel ranged from 1016±367 (maximum) to 247±44 (minimum) ng/g for the low rate and from 2845 (maximum) to 368±15 (minimum) ng/g for the high rate of application. The maximum amount of biphenthrin residues measured in the peach pulp was 47±10 ng/g while at 21-day after the third application and at 7-day after the fourth application the residues present were at levels lower than the detection limit (1 ng/g) for the method applied. In whole tomatoes the residues of biphenthrin ranged from 119±14 (maximum) to 31±2 (minimum) ng/g. Plots of 1nC versus t, where C is the amount of biphenthrin ng/cm² of peach leaf surface or per gram of fruit tissues and t is the post-application time in days, were constructed and the persistence half-lives of biphenthrin were calculated.     

Determination of clenbuterol in porcine tissues using solid-phase extraction combined with ultrasound-assisted dispersive liquid-liquid microextraction and HPLC-UV detection

A new pretreatment method, solid-phase extraction combined with dispersive liquid-liquid microextration (SPE-DLLME), was proposed in first time for the determination of clenbuterol (CLB) in porcine tissue samples. The tissue samples were firstly extracted by SPE, then its eluents were used as dispersant of the followed DLLME for further purification and enrichment of CLB. Various parameters (such as the type of SPE sorbent, the type and volume of elution solvent, the type and volume of extractant and dispersant, etc.) that affected the efficiency of the two steps were optimized. Good linearity of CLB was ranged from 0.19 μg/kg to 192 μg/kg with correlation coefficient (r2) of 0.9995. The limit of detection (LOD) was 0.07 μg/kg (S/N=3) and the recoveries at three spiked levels were ranged from 87.9% to 103.6% with the relative standard deviation (RSD) less than 3.9% (n=3). Under the optimized conditions, the enrichment factor (EF) for CLB could up to 62 folds. The presented method that combined the advantages of SPE and DLLME, had higher selectivity than SPE method and was successfully applied to the determination of CLB in tissue samples.     

Citrus waste recovery: a new environmentally friendly procedure to obtain animal feed

Citrus juice centrifugation pulp is the semi-solid product obtained from the industrial centrifugation of juices, to obtain a clear juice. This waste causes many economic and environmental problems because of its fermentability. In this paper we describe a method which makes it possible to obtain animal feed from citrus juice centrifugation pulp. To this end, alkaline and/or enzymatic treatments were carried out on the centrifugation pulp. These treatments facilitate pressing and so help to produce a material which, using suitable methods, may be dried. Enzyme treatment proved to be the most efficient of the methods under investigation designed to favour the pressing of the pulp. The product obtained with this method showed excellent digestibility in vitro and its protein content, although not especially high, compared favourably with that of many other agroindustrial waste products currently used as components of animal feed.     

Content of the <Emphasis Type="Italic">Alternaria</Emphasis> mycotoxin tenuazonic acid in food commodities determined by a stable isotope dilution assay

The Alternaria mycotoxin tenuazonic acid (TA) was quantified in fruit juices (n = 50), cereals (n = 12) and spices (n = 38) using a recently developed stable isotope dilution assay (SIDA). [¹³ C₆,¹⁵ N]-TA was used as the internal standard. Method validation revealed low limits of detection (LODs) of 0.15 μg/kg (fruit juices), 1.0 μg/kg (cereals) and 17 μg/kg (spices). The respective limits of quantitation were about three times higher. Recovery was about 100% for all matrices. The precision (relative standard deviation of replicate analyses of naturally contaminated samples) was 4.2% (grape juice; 1.7 μg/kg), 3.5% (whole wheat flour; 36 μg/kg) and 0.9% (curry powder; 215 μg/kg). The median content of TA in the analyzed samples was 1.8 μg/kg (fruit juices), 16 μg/kg (cereals) and 500 μg/kg (spices). Positive samples amounted to 86% (fruit juices), 92% (cereals) and 87% (spices).