Sprouting sterilization

Radioisotopes have important commercial applications. For example, americium-241 is used in smoke detectors. Its role is to ionize any smoke particles, which then allow a current to flow and set off the alarm. Exposure to radiation is also used to sterilize food and inhibit the sprouting of potatoes. Radioisotopes that give off a lot of energy as heat are also used to provide power in remote locations, where refueling of generators is not possible. Unmanned spacecraft, such as Voyager 2, are powered by radiation from plutonium. 

Microbial contamination, especially by salmonellas, is a risk when sprouts are produced commercially for human consumption. For recombinant protein production, seeds can be washed with water and surface-sterilized using hypochlorite solution. Sprouts can also be surface-sterilized during sprouting, by the addition of mild hypochlorite solution directly into the growth medium. Eventually, the hypochlorite is diluted out with pure water or growth medium. In our experiment on plate count agar [28], the sprouts showed no bacterial growth after sterilization with 1% sodium hypochlorite. 

E. coli 0157 H7 in radish sprouts Surface sterilization using 0.2% HgCl Itoh et al. (1998)... 

Though one tends to associate the inhibition of sprouting with sterilization, it is a quite unrelated phenomenon. The only similarity between prevention and sterilization is that in both instances one is suspending a life process. ... 

Radiation sterilization produces foods that are stable at room temperature and requires a dose of 20 to 70 kGy. At lower doses, longer shelf life may be obtained, especially with perishable foods such as fruits, fish, and shellfish. The destruction of Salmonella in poultry is an application for radiation treatment. This requires doses of 1 to 10 kGy. Radiation disinfestation of spices and cereals may replace chemical fumigants, which have come under increasing scrutiny in recent years. Dose levels of 8 to 30 kGy would be required. Other possible applications of irradiation processing are inhibition of sprouting in potatoes and onions and delaying of the ripening of tropical fruits. 

Brussels sprouts. 48 problems of, 48 seed sterilization for, 423 BT. See Bacillus thuringiensis BTI.460,474 BTK.459,460 BTSD.460... 

Figure 4 Typical radiation dose ranges for thedifferent utilizations of high-energy radiation in polymer processing. Doses for desinfection, sterilization and sprout prevention (biological effects) are given for comparison.

Inhibition of sprouting of potatoes and onions Killing and sterilizing insects (disinfestation of food)... 

Electron irradiation is useful in other areas, too. Foods can be irradiated, thereby allowing sterilization, and stabilization(g). For example, irradiation of potatoes kills any bugs, bacteria, etc., and eliminates germination/sprouting, which allows a great enhancement in storage-ability. Bectron irradiation is increasingly used in sterilization of medical devices and equipment(Z), and may even have promise in treatment of various waste streams. ... 

The hippocampus is sliced on a 200 pm polyester film of 2 x 3 cm (Pearl Paint) that has been extensively washed with 70% ethanol and air dned in a sterile hood Any plastic film can be used to support the hippocampus The film must be sterile and must resist being sliced by the tissue chopper blade There are consistent differences between cultures of the septal and temporal hippocampus that likely result from developmental gradients in the immature hippocampus (17), At postnatal d 10-11, the temporal end of the hippocampus is more mature than the septal end. Therefore, consistent differences can be observed between slice cultures originating from the temporal end or septal end. In particular, the mossy fiber projection differs between septal and temporal cultures (17) In septal cultures, there is mossy fiber sprouting mossy fiber terminals are found in the inner molecular layer of the dentate gyrus and the CA3 pyramidal cell layer. In temporal cultures, the mossy fiber projection is normal. This likely results in differences in slice culture excitability since epileptiform activity is more readily induced in septal cultures than temporal cultures (17). 

The purpose of irradiation can be (a) delaying or preventing sprouting, inactivation of molds and bacteria to prolong shelf life, (b) elimination of insects and parasites, (c) delaying ripening of foods, and (d) production of sterile products, which can he used without refrigeration. 

Another potential application of radioactive species is in food preservation (Figure 18.4). It is well known that gamma rays can kill insects, larvae, and parasites such as trichina that cause trichinosis in pork. Radiation can also inhibit the sprouting of onions and potatoes. Perhaps most important from a commercial standpoint, it can extend the shelf lives of many foods for weeks or even months. Many chemicals used to preserve foods have later been shown to have adverse health effects, so irradiation is an attractive alternative. Finally, irradiation can destroy microorganisms such as E. coli (which explains its use in treating beef) and anthrax (which explains its use in sterilizing suspected mail). 

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