EFFECT OF MECHANICAL PROCESSING AND LONG-TERM STORAGE ON BIOLOGICAL ACTIVITY OF VIRTUSS

1993 ◽  
Vol 125 (5) ◽  
pp. 975-977 ◽  
Author(s):  
W.J. Kaupp ◽  
P.M. Ebling

The effect of long-term storage on the activity of biological control products, particularly those containing nuclear polyhedrosis viruses (NPVs), has not been extensively studied. Most investigations involving viral insecticides have dealt with their thermal stability (Stuermer and Bullock 1968; Dulmage and Burgerjohn 1977; McLeod et al. 1977; Ignoffo and Couch 1981). Freeze-dried and air-dried powdered preparations of gypsy moth, Lymantria dispar L., NPV show little reduction in potency after storage at 4°C for 10 months and 3 months, respectively. Consequently, it was recommended that gypsy moth NPV be stored in either state at 4°C to maintain acceptable activity (Lewis and Rollinson 1978). TM BioControl-1, the viral product for control of the Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough), registered and used in the United States, has been shown to have a shelf life of 5 years if stored in a cool, dry place (Martignoni 1978). Virtuss is the NPV product manufactured in Canada, in the whitemarked tussock moth, O. leucostigma (J.E. Smith), since 1975 by the Forest Pest Management Institute, Forestry Canada, Sault Ste. Marie, Ont., for the control of the Douglas-fir tussock moth. It is routinely stored at 4°C in anticipation of tussock moth outbreaks and has been successfully used in the control of outbreaks of Douglas-fir tussock moth in Canada (Otvos et al. 1987). If these, or any other viral products are to be successful commercially, more information is required on the effect of storage on viral potency. Similarly, little information is known of the cumulative effects of the mechanical processes of lyophilization and milling on the biological activity of viral products. This note reports on the effects of mechanical processing and storage on Virtuss. Our results show that, although there is no immediate effect of mechanical processing, there can be substantial loss of biological activity of this product after 2 years of storage.

HortScience ◽  
2019 ◽  
Vol 54 (1) ◽  
pp. 143-148 ◽  
Author(s):  
Brianna L. Ewing ◽  
Gregory M. Peck ◽  
Sihui Ma ◽  
Andrew P. Neilson ◽  
Amanda C. Stewart

Hard cider production in the United States has increased dramatically during the past decade, but there is little information on how harvest and postharvest practices affect the chemistry of the resulting cider, including concentrations of organoleptically important flavanols. For 2 years we assessed fruit, juice, and cider from a total of five apple (Malus ×domestica Borkh.) cultivars in two experiments: sequential harvests and postharvest storage. Different cultivars were used in 2015 and 2016 with the exception of ‘Dabinett’, which was assessed in both years. There were no differences in polyphenol concentrations in cider made from fruit that was harvested on three separate occasions over a 4-week period in either 2015 or 2016. Fruit storage durations and temperatures had little influence on the chemistry when the experiment was conducted in 2015, but polyphenol concentration was greater after storage in the 2016 experiment. In 2016, total polyphenols in ‘Dabinett’ ciders were 51% greater after short-term storage at 10 °C and 67% greater after long-term storage at 1 °C than the control, which was not subjected to a storage treatment. In 2016, total polyphenols in ‘Binet Rouge’ ciders were 67% greater after short-term storage at 10 °C and 94% greater after long-term storage at 1 °C than the control. Although results varied among cultivars and harvest years, storing apples for longer periods of time and at warmer temperatures may be a strategy to increase polyphenol, particularly flavanol, concentrations in hard cider.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Aurore Bodzen ◽  
Audrey Jossier ◽  
Sébastien Dupont ◽  
Pierre-Yves Mousset ◽  
Laurent Beney ◽  
...  

Abstract Background Stabilization of freeze-dried lactic acid bacteria during long-term storage is challenging for the food industry. Water activity of the lyophilizates is clearly related to the water availability and maintaining a low aw during storage allows to increase bacteria viability. The aim of this study was to achieve a low water activity after freeze-drying and subsequently during long-term storage through the design of a lyoprotectant. Indeed, for the same water content as sucrose (commonly used lyoprotectant), water activity is lower for some components such as whey, micellar casein or inulin. We hypothesized that the addition of these components in a lyoprotectant, with a higher bound water content than sucrose would improve lactobacilli strains survival to long-term storage. Therefore, in this study, 5% whey (w/v), 5% micellar casein (w/v) or 5% inulin (w/v) were added to a 5% sucrose solution (w/v) and compared with a lyoprotectant only composed of 5% sucrose (w/v). Protective effect of the four lyoprotectants was assessed measuring Lactiplantibacillus plantarum CNCM I-4459 survival and water activity after freeze-drying and during 9 months storage at 25 °C. Results The addition whey and inulin were not effective in increasing Lactiplantibacillus plantarum CNCM I-4459 survival to long-term-storage (4 log reduction at 9 months storage). However, the addition of micellar casein to sucrose increased drastically the protective effect of the lyoprotectant (3.6 log i.e. 0.4 log reduction at 9 months storage). Comparing to a lyoprotectant containing whey or inulin, a lyoprotectant containing micellar casein resulted in a lower water activity after freeze-drying and its maintenance during storage (0.13 ± 0.05). Conclusions The addition of micellar casein to a sucrose solution, contrary to the addition of whey and inulin, resulted in a higher bacterial viability to long-term storage. Indeed, for the same water content as the others lyoprotectants, a significant lower water activity was obtained with micellar casein during storage. Probably due to high bound water content of micellar casein, less water could be available for chemical degradation reactions, responsible for bacterial damages during long-term storage. Therefore, the addition of this component to a sucrose solution could be an effective strategy for dried bacteria stabilization during long-term storage.


2020 ◽  
Vol 32 (2) ◽  
pp. 146
Author(s):  
L. Palazzese ◽  
D. A. Anzalone ◽  
P. Toschi ◽  
P. Loi

Semen lyophilisation is an interesting technique that might be a cheap alternative to long-term storage in liquid nitrogen. The first significant result of this method was achieved by Wakayama and Yanagimachi in the 1998 and demonstrated, for the first time, the birth of healthy mouse pups from epididymal freeze-dried (mouse) spermatozoa. The authors follow the lyophilisation technique, commonly used in the pharmaceutical and food industries, namely, deep freezing, which requires direct immersion of the semen sample into liquid nitrogen before vacuum drying. In this work, we focused on the freezing phase to improve and make the technique more reliable. We compared two protocols: 1) rapid freezing, where the semen is plunged directly into liquid nitrogen (LN group), and 2) slow freezing, where the sample is frozen with a freezing rate of 1°C min−1 until −50°C (SL group). Then, both frozen samples were lyophilized. Subsequently, after an interval ranging between 1 and 3 months, dry spermatozoa from LN and SL groups were used for intracytoplasmic sperm injection (ICSI), and the embryo development was evaluated at 24h (2-cell stage) and 7 days (expanded blastocyst) post-ICSI. Moreover, acrosome integrity was evaluated with Pisum sativum agglutinin (PSA) staining on part of the semen, immediately after freezing. The LN-group semen showed the acrosome completely melted, whereas the SL group showed better integrity of the acrosome, which was comparable to that of the normal frozen (vital) spermatozoa. At 24h post-ICSI the number of cleaved embryos in the SL group was higher than in the LN group (42/100 (42%) vs. 19/75 (25.3%), SL and LN, respectively; P=0.0253). The blastocyst rate 7 days after ICSI in the SL group was higher (7/100 (7%) than that in the LN group (2/75 (2.7%); P=0.0238). Our data show that lyophilisation can be conveniently achieved in ram spermatozoa without liquid nitrogen, thus simplifying the procedure. These data support the idea that lyophilisation might be a valuable and cheaper alternative to liquid nitrogen for long-term storage of ram semen.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1052
Author(s):  
Yub Neupane ◽  
Chenyuan Huang ◽  
Xiaoyuan Wang ◽  
Wei Heng Chng ◽  
Gopalakrishnan Venkatesan ◽  
...  

Recently, bioinspired cell-derived nanovesicles (CDNs) have gained much interest in the field of nanomedicine due to the preservation of biomolecular structure characteristics derived from their parent cells, which impart CDNs with unique properties in terms of binding and uptake by target cells and intrinsic biological activities. Although the production of CDNs can be easily and reproducibly achieved with any kind of cell culture, application of CDNs for therapeutic purposes has been greatly hampered by their physical and chemical instability during long-term storage in aqueous dispersion. In the present study, we conceived a lyophilization approach that would preserve critical characteristics regarding stability (vesicles’ size and protein content), structural integrity, and biological activity of CDNs for enabling long-term storage in freeze-dried form. Compared to the lyoprotectant sucrose, trehalose-lyoprotected CDNs showed significantly higher glass transition temperature and lower residual moisture content. As assessed by ATR-FTIR and far-UV circular dichroism, lyophilization in the presence of the lyoprotectant effectively maintained the secondary structure of cellular proteins. After reconstitution, lyoprotected CDNs were efficiently associated with HeLa cells, CT26 cells, and bone marrow-derived macrophages at a rate comparable to the freshly prepared CDNs. In vivo, both lyoprotected and freshly prepared CDNs, for the first time ever reported, targeted the injured heart, and exerted intrinsic cardioprotective effects within 24 h, attributable to the antioxidant capacity of CDNs in a myocardial ischemia/reperfusion injury animal model. Taken together, these results pave the way for further development of CDNs as cell-based therapeutics stabilized by lyophilization that enabled long-term storage while preserving their activity.


2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Yuko Kamada ◽  
Sayaka Wakayama ◽  
Ikue Shibasaki ◽  
Daiyu Ito ◽  
Satoshi Kamimura ◽  
...  

Author(s):  
B A Middleton ◽  
L M Morgan ◽  
G W Aherne ◽  
V Marks

The performance in radioimmunoassay of four antisera after storage at temperatures ranging from −40°C to room temperature, in three physical states (frozen, liquid or freeze dried) was investigated over a 3-year period. No deterioration in antiserum performance in terms of precision and accuracy of quality control serum measurement or recovery of ligand was apparent under any of the storage conditions studied. Some lowering of titre became apparent in two of the antisera over the study period. Deterioration was most marked when antiserum was stored lyophilised at room temperature. Storage of antiserum frozen confers no advantage over storage at 4°C provided precautions are taken to minimise bacterial contamination when storing antiserum in liquid form.


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