In vivo research following ingesting of commercially available
Lactobacillus tablets, which contain about 2X10⁶ cfu/tablet of
Lactobacillus acidophilus and Lactobacillus bulgaricus cells in a dose
of four tablets daily, showed serum lipoprotein concentrations did not
change significantly. In order to increase the number of viable
Lactobacillus bacteria after challenging in low pH solution (gastric
fluid), enteric coating polymer was applied over dried calcium alginate
beads containing Lactobacillus. Survival of Lactobacillus bacteria was
generally higher from freeze dried calcium alginate beads compared to
vacuum dried products. However, after pretreatment with simulated
gastric fluid (pH = 1.5) for 2 hours, only the coated products from
vacuum drying showed promising results. Lactobacillus bacteria were
fully protected against gastric pH after formulating the bacteria inside
mini-tablets which were coated with Eudragit L30D, an enteric coating
polymer.
Alginic acids are naturally occurring substances found only in the
brown seaweeds. Alginic acid salts formed with most di-, and polyvalent
metals are insoluble in water. The most common application of alginate
precipitation in drug product formulation is based on insolubilization
of alginate by addition of calcium salt. By altering the composition of
calcium alginate, drug loading, enteric coating thickness, and sustained
release coating thickness, the lag time for drug dissolution can be
controlled. This formulation research provides oral dosage form design
for targeted delivery of drug to any desired site in the
gastrointestinal tract. Examples of site specific targeted delivery are
given for Lactobacillus bacteria, ibuprofen, sulfasalazine, and
5-aminosalicylic acid. / Graduation date: 1991
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/37470 |
| Date | 02 August 1990 |
| Creators | Lin, Shun Yih |
| Contributors | Ayres, James W. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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