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PubMed2000

Effect of packaging conditions on the growth of micro-organisms and the quality characteristics of fresh mushrooms (Agaricus bisporus) stored at inadequate temperatures.

Mushrooms were packed in two polymeric films (perforated and non-perforated PVC) and stored at 17 degrees C and 25 degrees C. The carbon dioxide and oxygen content inside the packages, aerobic mesophiles, Pseudomonas spp., faecal coliforms, Escherichia coli, anaerobic spores and major sensory factors (colour, texture, development stage and presence of moulds) were determined. The non-perforated packages had the highest contents of CO2 (6-7%), the lowest contents of O2 (0.013-0.17%) and the most desirable quality parameters (texture, development stage and absence of moulds). Pseudomonas spp. counts were around 1 logarithmic unit lower in mushrooms packaged in non-perforated film as the O2 concentrations were lower than in perforated film. The mushrooms themselves were inoculated with an enterotoxin A-producing strain of Staphylococcus aureus, packaged in overwrapped trays and stored at 17 and 25 degrees C. Staphylococcus aureus did not grow in the samples stored at 17 degrees C. Only slight growth was observed in mushrooms packaged with non-perforated film after 1 day at 25 degrees C. No enterotoxin was detected in any package. Faecal coliform counts were <2 log cfu g(-1). Escherichia coli was not isolated in any of the samples. At 25 degrees C, counts of anaerobic spores of around 2 log cfu g(-1) were detected in those mushrooms packaged in non-perforated film.

Agaricus↗

PubMedDate not supplied

HACCP approach to ensure the safety and quality of food packaging.

EC Directive 93/43/EEC of 14 June 1993 on the hygiene of foodstuffs has been implemented in the Netherlands through the Food and Commodity Act (Warenwet) of 14 December 1995. This Directive requires food companies to identify steps in their activities that are critical to ensuring food safety, and to ensure that adequate safety procedures are identified, implemented, maintained and reviewed based on the principles of the Hazard Analysis Critical Control Point (HACCP) system. HACCP is a tool used to assess hazards, estimate risks and establish specific control measures that emphasize prevention and control rather than reliance on end-product testing. Increasing public awareness of food safety, together with the introduction of this new legislation, has led producers and retailers of food to demand higher standards from their suppliers. Suppliers of raw materials, ingredients and also food packaging will be expected to bring their standards of hygiene in line with the expectations of the food industry. Food producers will need to obtain the guarantee from their suppliers that the packaging does not negatively influence their products. HACCP is a method that can also be applied to ensure the safety and other quality aspects of all kinds of food packaging materials such as films, foils, trays, cups, boxes and tubs made of paper, cardboard, polymers, metal and other materials (single use or disposable packagings as well as re-usable and recycled packagings). At the Netherlands Organization for Applied Scientific Research (TNO), the quality and safety aspects of re-use of food packaging, and refillable bottles in particular, have been the subject of extensive investigations in the project 'Quality monitoring of synthetic refillable bottles'. In this paper the set-up of the project and the Codes of Practice for refillable bottles are described. Moreover, the applicability of HACCP to food packagings and an example of a HACCP study for refillable PET bottles will be discussed.

Conservation of Natural Resources↗

PubMedDate not supplied

Effects of packaging and storage conditions on volatile compounds in gas-packed poultry meat.

Volatile compounds released by raw chicken legs packed in modified atmosphere packages were determined in order to develop a spoilage indicator for monitoring the shelf-life of raw chicken. Internal spoilage indicators would react with compounds released during chemical, enzymatic and/or microbial spoilage reactions. The effects of four packaging factors (headspace volume, oxygen transmission rate of the package, residual oxygen and carbon dioxide concentration) and three storage factors (temperature, illumination and storage time) on the amounts of volatile compounds in the headspace of gas packages containing two chicken legs were studied. Statistical experimental design was applied and a linear screening design comprising 18 experiments (fractional factorial) was utilized. Volatile compounds in package headspace were determined by gas chromatography--mass spectrometry using the dynamic headspace technique. The results were compared with the results of sensory evaluation and microbial determinations. The head-space of stored packages was dominated by the following compounds: butene, ethanol, acetone, pentane, dimethylsulphide, carbon disulphide and dimethyl disulphide. In modelling, some interaction terms and squared terms were needed in addition to linear terms. The main factors affecting the amounts of ethanol, dimethyl sulphide, carbon disulphide and dimethyl disulphide were storage time and temperature. Other factors had only minor importance, carbon dioxide concentration and headspace volume being the most significant package parameters. The same four factors also had the greatest effects on the odour of chicken legs.

Acetone↗

PubMed1999

Packaging effects on shell egg breakage rates during simulated transportation.

Shell eggs were packaged in either expanded polystyrene (EPS) foam or molded paper pulp (MPP) one dozen cartons, then were bulk packaged in either polypropylene crates or corrugated boxes. The packages were then subjected to a well-defined computer-simulated vibration test on an electrohydraulic test machine. The percentage and the location on the egg (side, top, bottom) of breakage was determined in the secondary (corrugated box or polypropylene crate) and primary (EPS or MPP carton) package after 15, 75, and 180 min. For each of three trials, 60 dozen Grade A large eggs were randomly assigned to each primary package and cross-stacked in a secondary container that contained three cartons in a row and a total of five layers. When cartons were packed in 15-dozen corrugated boxes, no significant difference was found in total eggshell damage rates between the MPP carton and the EPS carton. However, when eggs were packed in 15-dozen plastic crates, the MPP cartons caused significantly less eggshell damage than the EPS cartons. The EPS cartons packed in corrugated boxes had the lowest breakage (4.63%), whereas the EPS foam cartons packed in plastic crates had the highest breakage (12.59%). When the effect of secondary packaging and vibration time were not considered, no significant difference was found between MPP and EPS cartons. In addition, when the effect of primary packaging was not taken into account, the corrugated boxes had significantly lower breakage rates than the plastic crates. Nearly 55% of the breakage occurred in the bottom section of the eggshell as compared to the side and top. When the test periods were compared, the EPS cartons packed in plastic crates had the highest breakage (16.28%) at 180 min.

Animals↗

PubMed2007

Efficient DNA packaging of bacteriophage PRD1 requires the unique vertex protein P6.

The assembly of bacteriophage PRD1 proceeds via formation of empty procapsids containing an internal lipid membrane, into which the linear double-stranded DNA genome is subsequently packaged. The packaging ATPase P9 and other putative packaging proteins have been shown to be located at a unique vertex of the PRD1 capsid. Here, we describe the isolation and characterization of a suppressor-sensitive PRD1 mutant deficient in the unique vertex protein P6. Protein P6 was found to be an essential part of the PRD1 packaging machinery; its absence leads to greatly reduced packaging efficiency. Lack of P6 was not found to affect particle assembly, because in the P6-deficient mutant infection, wild-type (wt) amounts of particles were produced, although most were empty. P6 was determined not to be a specificity factor, as the few filled particles seen in the P6-deficient infection contained only PRD1-specific DNA. The presence of P6 was not necessary for retention of DNA in the capsid once packaging had occurred, and P6-deficient DNA-containing particles were found to be stable and infectious, albeit not as infectious as wt PRD1 virions. A packaging model for bacteriophage PRD1, based on previous results and those obtained in this study, is presented.

Bacteriophage PRD1↗

PubMed2001

Progress and problems in the prescribing/dispensing split and "divided package sales" by wholesalers.

Given the rapid progress of the prescribing/dispensing split, the ability of pharmacies to obtain and stock a small quantity of pharmaceuticals is seen as essential. Toho Yakuhin's experience in "divided package sales" (wholesalers open an original package supplied by the manufacturer and sell only a part of the contents) shows that the number of orders and sales amount, and the number of pharmacies ordering in sales have remarkably increased. One or two kinds of pharmaceuticals were ordered in 73% cases, and one or two units in about 50%. This implies that "divided package sales" are utilized to obtain rarely prescribed drugs. On the other hand, five or more kinds of pharmaceuticals were ordered in 10% of cases, and ten or more units in 17%. "Divided package sales" were more used for low-price drugs. These indicated that "divided package sales" seemed to be looked upon by pharmacies as a means of obtaining a small quantity of pharmaceuticals, and seemed to be used not only in an emergency but also routinely. There are several problems for wholesalers in operating "divided package sales", such as frequent delivery, delivery cost and information supply. Pharmacies should obtain a small quantity of pharmaceuticals by the routine delivery and should share the delivery cost. Pharmaceutical manufacturers' cooperation in printing necessary information on each immediate container will be useful. Though there could be alternative ways of obtaining a small quantity of pharmaceuticals, all of them have the matter of delivery. We believe "divided package sales" will contribute to this situation.

Commerce↗

PubMed1988

Comparison of packages for suppositories by patients with rheumatoid arthritis.

Ninety-four patients with rheumatoid arthritis were asked via a questionnaire about the convenience of packages containing tablets, capsules, or suppositories for home use. Almost half of the patients stated that they had difficulty in opening packages containing capsules or tablets, and two-thirds had difficulty with the packages used for suppositories. The characteristics of six packages used for suppositories were also compared. Patients were given the packages in random order and were asked to open them and remove a suppository. Many of them were unable to open three of the packages with their hands. The evaluation of the six packages by the patients differed widely.

Activities of Daily Living↗

PubMed1998

Microbiological quality and the inability of proteolytic Clostridium botulinum to produce toxin in film-packaged fresh-cut cabbage and lettuce.

The production of toxin by a 10-strain mixture of proteolytic Clostridium botulinum in fresh produce packaged in polyethylene films having high (7,000 cc/m2/24 h; HOTR) and low (3,000 cc/m2/24 h; LOTR) relative oxygen permeability was determined. Shredded cabbage and lettuce inoculated with approximately 10(2) spores/g were placed in bags composed of the two films (1.4 kg/bag), and the bags were then vacuum sealed. Produce was stored at 4, 13, and 21 degrees C for up to 21 (cabbage) or 28 (lettuce) days and analyzed periodically. At each sampling time, the gas composition within the bags, pH of the produce, and microbial populations (total aerobic and anaerobic microorganisms, lactic acid bacteria, psychrotrophic bacteria, and yeasts and molds) were determined. In addition, the presence of botulinal toxin was determined using the standard U.S. Food and Drug Administration mouse bioassay protocol. Bags made of HOTR film prolonged sensory quality of cabbage and lettuce, especially at 13 and 4 degrees C. Packaging material had an effect on the growth of various groups of microorganisms; however, there was not a general trend. For example, lettuce packaged in HOTR bags had higher aerobic microbial populations than that packed in LOTR, but no significant difference (P < or = 0.05) was observed with cabbage. Growth of psychrotrophic bacteria was greater in vegetables packaged in HOTR film while growth of yeasts and molds was not affected by either packaging film. Most differences in microbial populations in produce packaged in LOTR and HOTR films were less than 1 log10 CFU/g. Botulinal toxin was not detected in cabbage or lettuce packaged in either film or stored under any test condition.

Animals↗

PubMed1999

Evaluation of botulinal toxin production in packaged fresh-cut cantaloupe and honeydew melons.

The ability of Clostridium botulinum to produce toxin on cubed, packaged melons was investigated relative to microbial spoilage at various incubation temperatures and in different packaging systems. Freshly cut cubes (approximately 2.5 cm3) of cantaloupe and honeydew melons were surface inoculated with a 10 strain mixture of proteolytic and nonproteolytic spores of C. botulinum (10 to 15 cubes per package; approximately 100 total spores per package). To initially evaluate toxin production and spoilage in a passively modified atmosphere, melon cubes were loosely packaged in air in polyethylene pouches, sealed, and incubated at 7 or 15 degrees C for up to 21 days. At various sampling intervals, samples were tested for headspace oxygen and carbon dioxide levels, pH, presence of botulinal toxin, aerobic and anaerobic plate counts, and counts of yeasts and molds. During incubation, headspace oxygen levels decreased, headspace carbon dioxide levels increased, aerobic and anaerobic plate counts increased, and the pH remained constant or decreased slightly. Botulinal toxin was not detected in any cantaloupe samples or in honeydew samples incubated at 7 degrees C. Botulinal toxin was detected in some honeydew samples at 15 degrees C after 9 days of incubation, but the toxic honeydews were severely spoiled and considered organoleptically unacceptable. A similar second experiment was performed in which half of the melon cubes were treated with UV light to inactivate vegetative organisms before packaging, and these were incubated at 7, 15, or 27 degrees C. In this second experiment, toxin production occurred in the UV-treated samples at 15 degrees C with gross spoilage and at 27 degrees C with only marginal spoilage. These data indicate that inhibition of spoilage organisms with UV light could result in botulinal toxin formation in packaged melons before overt spoilage.

Bacteria, Aerobic↗

PubMed2003

[The role of the packaging in terms of safety and good use of medicines].

The pharmaceutical packaging is an essential constituent of medicinal products because it guarantees its stability and integrity. It is sometimes an intrinsic part of the pharmaceutical form itself. Furthermore, the pharmaceutical packaging has always been an essential information medium for patients (labelling, leaflet) but also for professionals (such as pharmacists, other pharmacy staff or nurses) at the time of drug delivery. Of course, the information delivered to the patient through the packaging has to be in accordance with the Marketing Authorization terms. Besides, this information is included in the drug Marketing Authorization (annexes II and III). The information delivered has to be clear because patients generally refer to the leaflet when no professional is available for advice. An easy-to-use pharmaceutical packaging also guarantees the good use of medicinal products and promotes patient compliance (for example, pack and calendar blisters). It is also a safety guarantee when it uses specific methods, such as single-dose packaging (particularly in hospital setting) or safety caps for children. The drug leaflet must clearly mention utilisation for some difficult use forms (case of medicinal products for asthma or insulin pens). Lastly, the pharmaceutical packaging also helps to recognize the drug, which in itself is part of the safety process all along the supply chain. Indeed, drug packaging's major role is to avoid confusion with other drugs among professionals and patients alike.

Drug Labeling↗

PubMed2026

Branded packaging raises likelihood of cigarette purchasing in an experimental retail setting by increasing craving.

INTRODUCTION: Exposure to branded cigarette packaging in retail settings has been shown to be associated with purchasing behavior, but the mechanisms underlying this effect are unclear. This study tested whether cigarette craving and perceived health harms mediate the effect of branded packaging on cigarette purchasing in a simulated retail environment. METHODS: Young adults aged 21-34 who currently smoke cigarettes (n = 290) completed an experimental shopping task in the RAND StoreLab, a life-sized replica of a convenience store. Participants were randomly assigned to one of two conditions: (1) branding present, in which branded cigarette packages were displayed; and (2) branding absent condition, in which branded elements were removed and packages were standardized in a brown-green color and uniform text. Cigarette purchases were recorded, and participants completed post-shopping measures of cigarette craving and perceived health harms. Causal effect decomposition analyses were used to assess whether these variables mediated the effect of study condition on the likelihood of purchasing cigarettes. RESULTS: Craving, but not perceived health harms, partially mediated the effect of branded packaging on cigarette purchasing. Exposure to branded packs increased the likelihood of purchasing by elevating craving (average mediated effect = 2.4%, 95% CI 0.2% - 5.0%, p = .03). CONCLUSIONS: Branded cigarette packaging appears to increase cigarette purchasing at least in part by increasing cigarette craving at point of sale. Interventions that address craving management in retail settings (e.g., just-in-time interventions, prn nicotine replacement therapy) may help mitigate the impact of branding on young adults' cigarette purchasing.

Humans↗

PubMedDate not supplied

Large-scale manufacturing of safe and efficient retrovirus packaging lines for use in immunotherapy protocols.

BACKGROUND: The use of gene modified T lymphocytes for immunotherapy in a cancer or AIDS clinical trial requires an efficient, safe ex vivo method for modification of these cells at manufacturing scale. Since retroviruses have been shown to be a moderately effective means of stably integrating therapeutic genes into T lymphocytes, we wanted to create packaging and producer cell lines that would produce replication competent retrovirus (RCR)-free supernatants, at large scale (> 200 l), and transduce with high efficiency. METHODS: cDNA expression plasmids containing only coding sequences for gagpol or env were built and sequentially transfected into human 293 cells. Packaging and producer clones were characterized for stability, titer and RCR. A producer clone delivering chimeric immune receptors was scaled-up and supernatants used to transduce patient T lymphocytes for clinical studies. PCR and RT-PCR assays were utilized to evaluate the transmission of HERV-H sequences. Relative infectivity of producer clones pseudotyped with different envelopes was determined by transduction and RT assays. RESULTS: RCR-free, human 293 split-genome packaging lines, pseudotyped with amphotropic, xenotropic, or 10A1 envelopes, were created. A CC49 zeta producer clone was scaled-up to 5 x 54 l lots and supernatants used to safely and efficiently transduce patient T lymphocytes with minimal ex vivo manipulation. While 293 cells express HERV-H mRNA, the transmission frequency in our packaging clones was less than 1 HERV-H sequence per 5 x 10(5) proviral integrations. Additionally, 10A1 and xenotropic packaging lines had higher infectivities than the amphotropic clone. CONCLUSION: These packaging lines represent the safest configuration for the large-scale production of retroviral vectors, and are capable of producing high titer, RCR-free retroviral vector for large scale clinical use. While all three clones efficiently transduce human T lymphocytes, the 10A1 clone has the highest infectivity. These packaging cell lines will be valuable for use in human gene therapy protocols.

Animals↗

PubMed2005

Generation of a packaging cell line for prolonged large-scale production of high-titer HIV-1-based lentiviral vector.

BACKGROUND: A stable packaging cell line facilitates large-scale lentivirus vector manufacture. However, it has been difficult to produce clinical-scale HIV-1-based lentiviral vectors using a packaging cell line, in part due to toxicity of packaging genes, and gene silencing that occurs during the long culture period necessary for sequential addition of packaging constructs. METHODS: To avoid these problems, we developed a three-level cascade gene regulation system designed to remove tetracycline transactivator (tTA) from cytomegalovirus immediate early promoter (CMV)-controlled expression to reduce cytotoxicity from constitutive expression of tTA and leaky expression of packaging genes. We also performed a one-step integration of the three packaging plasmids to shorten the culture time for clonal selection. RESULTS: Although leaky expression of p24 and vector production still occurred despite the three-level regulation system, little cytotoxicity was observed and producer cells could be expanded for large-scale production. Producer cells yielded remarkably stable vector production over a period greater than 11 days with the highest titer 3.5 x 10(7) transducing units (TU)/ml and p24 300 ng/ml, yielding 2.2 x 10(11) TU and 1.8 milligram (mg) p24 from one cell factory. No replication-competent lentivirus (RCL) was detected. Long-term analysis demonstrated that, although the cells are genetically stable, partial gene silencing occurs after 2-3 months in culture; however, the one-step construct integration allowed prolonged vector production before significant gene silencing. Concentrated vector resulted in 90% transduction in CD4+ lymphocytes at 20 TU per cell. CD34+ progenitor cells were transduced at 41-46% efficiency, and long-term initiating culture (LTC-IC) was transduced at 45-51%. CONCLUSIONS: These results demonstrate for the first time HIV-1-based lentiviral vector production on the large scale using a packaging cell line.

Base Sequence↗

PubMed1995

RNA binding, packaging and polymerase activities of the different incomplete polymerase complex particles of dsRNA bacteriophage phi 6.

phi 6 is an enveloped dsRNA bacterial virus. Its segmented genome resides inside the virion associated polymerase complex which is formed by four proteins (P1, P2, P4 and P7) encoded by the viral L segment. Complete and incomplete polymerase complex particles can be produced using cDNA copies of this largest genome segment. We have analysed the capacity of the different purified particles to (1) package phi 6 (+) sense genomic precursors and unspecific RNA, (2) synthesize (-) and (+) strands and (3) bind phi 6 specific and unspecific RNAs. Both (-) and (+) strand synthesis polymerase activities were found to be associated with protein P2. In addition to complete particles, particles lacking protein P2 were found to package and protect genomic precursor ssRNAs. Protein P7 was needed for efficient packaging. Regulation and specificity of the packaging were found to be independent of P2. Particles composed of proteins P1 and P4 did not package or protect RNA but did bind phi 6 genomic (+) strand RNAs. The three phi 6 (+) strands bound in equal amounts to the particles when tested alone in a filter binding assay. In competition experiments they competed each other for binding, indicating that individual binding sites for the three genomic (+) strands do not exist. Differences in RNA binding competition among the four particles were observed, suggesting that packaging specificity is achieved by complex interactions of proteins and genomic (+) strand RNAs during the advancement of the packaging process after the initial binding events.

Bacteriophage phi 6↗

PubMed1993

The direction and rate of bacteriophage T7 DNA packaging in vitro.

To determine the direction of the entry of DNA during in vitro bacteriophage T7 DNA packaging, incompletely packaged DNA (ipDNA) was fractionated by agarose gel electrophoresis after degradation of DNA outside of capsids and then release of packaged DNA from capsids. After fractionation, quantitative in-gel probing with a right end-specific oligonucleotide detects heterogeneous ipDNA (called right-end ipDNA). Most of the right-end ipDNA appears with kinetics expected of a precursor to the mature T7 DNA. In-gel probing with a left-end-specific oligonucleotide detects ipDNA (left-end ipDNA); the molar amount of left end ipDNA is always at least 50x less than the molar amount of right-end ipDNA. Left-end ipDNA appears with the kinetics of an abortive end product of T7 DNA packaging. Thus, productive T7 DNA packaging occurs in a right-to-left direction. Quantitation of the conversion of right-end ipDNA to mature-length DNA yields an estimate of the mean rate of right-to-left in vitro T7 DNA packaging: 28 +/- 6 kbp/min for the last 20-50% of the DNA packaged.

Bacteriophage T7↗

PubMed1995

Analysis of the fine structure of the prohead binding domain of the packaging protein of bacteriophage T3 using a hexapeptide, an analog of a prohead binding site.

A large subunit of bacteriophage T3 packaging enzyme, a product of gene 19 (gp19, 586 amino acid residues), binds a prohead prior to DNA translocation in DNA packaging. Its C-terminal region (571 to 576, Region I) is of crucial importance for prohead binding. To elucidate the functional role(s) of Region I in DNA packaging, a hexapeptide (6pT3) corresponding to the Region I sequence and its variants were synthesized and their effects on DNA packaging in a defined in vitro system were examined. 6pT3 did not inhibit gp19wt (wild type)-prohead binding but interfered with their functional interaction, resulting in inhibition of DNA packaging. The inhibitory effect of 6pT3 on gp19wt was reversible. The effect of 6pT3 was examined with gp19 delta C10, which was active in DNA packaging in spite of lacking the extreme C-terminal 10 amino acids (Region II). The inhibitory effect on gp19 delta C10 was more severe than that on gp19wt and was irreversible. From these results, we concluded that the prohead binding domain is composed of two subdomains: Region I is a "core" domain, and its binding to the prohead is crucial for DNA packaging, and Region II is an "anchor" domain stabilizing the binding by Region I.

Amino Acid Sequence↗

PubMed1998

Isolation of a mutant that changes genomic packaging specificity in phi6.

Bacteriophage phi6 has a genome of three segments of double-stranded RNA enclosed in a polyhedral procapsid. Plus strand transcripts of the segments are packaged in a serially dependent fashion in which S can package alone, M depends on S, and L depends on S and M. We have isolated a mutant form of the virus in the carrier state that has lost segment S. This finding presented an apparent anomaly with respect to the packaging program. Sequencing of gene 1 of segment L in this virus showed a translational change of arginine to glycine at the 14th position. Procapsids prepared from cDNA containing this mutation show behavior in in vitro packaging that is consistent with the phenotype of the mutant virus. The procapsids are able to package segment S alone, but this RNA is present in reduced amounts when the other segments are present. Segments M and L package without dependence on segment S. The mutant virus appears to produce procapsids that are at the second stage of the packaging program.

Bacteriophage phi 6↗

PubMed1998

Characterization of coronavirus DI RNA packaging.

Studies of defective interfering (DI) RNAs of mouse hepatitis virus (MHV), suggest that a 69 nt-long packaging signal, which is located about 20 kb from the 5'-end of the 31 kb-long MHV genomic RNA, is necessary and sufficient for MHV genomic RNA packaging into MHV particles. We demonstrated that use of a low pH culture medium combined with subsequent ultrafiltration increased MHV infectivity about 60 times over MHV preparations grown in neutral medium. Using this virus concentration procedure, we successfully prepared DI particle-rich MHV preparations. Characterization of virus samples released from the cells infected with DI particle-rich MHV revealed that infectious MHV genomic RNA was not required for packaging of DI RNAs. These data suggested that interaction of the DI packaging signal with an unidentified region(s) of helper virus genomic RNA is unlikely, and therefore unlikely to facilitate the packaging of MHV DI RNA into the MHV virion. Rather, both DI RNA and MHV genomic RNA probably use the packaging signal for RNA packaging.

Animals↗