Stability of extracts from pollens of allergenic importance in Korea

Abstract

Background/Aims: Accurate diagnosis and the effects of allergen-specific immunotherapy for pollinosis are greatly dependent on the potency and stability of the extract. This study aimed to examine factors, such as temperature and storage buffer composition, that affect the stability of allergen extracts from pollens of allergenic importance in Korea. Methods: We prepared four pollen allergen extracts from ragweed, mugwort, Japanese hop, and sawtooth oak, which are the most important causes of seasonal rhinitis in Korea. Changes of protein and major allergen concentration were measured over 1 year by Bradford assay, two-site enzyme-linked immunosorbent assay, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis after reconstitution of the lyophilized allergen extract in various buffers and stored at room temperature (RT, 18°C to 26°C) or refrigerated (4°C). Results: More than 90% of the original protein concentration in all four extracts examined was detected over 1 year when 50% glycerol was added and refrigerated, whereas 57.9% to 94.5% remained in the extracts at RT. The addition of 50% glycerol to the storage buffer was found to prevent protein degradation at RT. Amb a 1, a major allergen of ragweed, was almost completely degraded in 9 weeks at RT when reconstituted in a buffer without 50% glycerol. However, 55.6% to 92.8% of Amb a 1 content was detected after 1 year of incubation at 4°C in all buffer conditions except 0.3% phenol. Conclusions: Addition of 50% glycerol as well as refrigeration was found to be important in increasing the shelf-life of allergen extracts from pollens of allergenic importance.

Eudragit-Coated Sporopollenin Exine Microcapsules (SEMC) of Phoenix dactylifera L. of 5-Fluorouracil for Colon-Specific Drug Delivery

“…Due to the excellent biocompatibility, low toxicity, consistency in size, resistance to even tough chemical conditions, and high-temperature stability, SEMC obtained from pollens of different species have been used as green carriers for many drugs [72]. There are numerous reports available regarding the stable shelf-life of pollens and their extracts [73][74][75]. Thus, in the present investigation, only a few parameters including the size, encapsulation (%EE), and drug-loading capacity (%DL) of SEMC were determined after Thus, we could postulate that the release of 5-FU from F2-ERS was the combination of dissolution, diffusion, and polymer-erosion, which was similar to the previous reports [13,22,71].…”

Comparison of Allergenic Properties among Commercially Available House Dust Mite Allergen Extracts in Korea

“… 4 Previous studies have been performed for standardization of extracts for house dust mite (HDM), 5 cockroach, 6 pollens of regional importance, 7 insect venom component allergen (Pac c 3 from Pachycondyla chinensis ), 8 and buckwheat. 9 The stabilities of extracts for HDM, 10 cockroach, 11 and pollens 12 have also been studied. Standardization of food allergens, including cereals and various regionally important fish species, is ongoing.…”