Fermentation of shrimp head was conducted using Streptococcus thermophilus to produce antioxidant and recover chitin. Fermentation conditions were found to be 10% shrimp head concentration, 5% glucose concentration, 1.2%(v/v) inoculum size, and 64 h of incubation time at 42°C to attain an initial pH of 5.00 with response surface method optimization and the actual deproteinization rate obtained was 93.59%. Antioxidant activity in the supernatant fluid increased greatly during fermentation, the DPPH radical scavenging ability of the culture supernatant was about 98.70%. The concent-ration of astaxanthin, phenolic compounds, and free amino acid in the culture supernatant was 1.774 μg/mL, 589.69 μg gallic acid equivalents/mL, and 796.978mg/mL, respectively. Comparison of the FT-IR spectra and X-ray diffraction (XRD) analysis among commercial chitin (CTa), chitin prepared by the S. thermophilus fermentation (CTb), and chitin prepared by chemical treatments (CTc) demonstrated that CTb had the highest degree of deacetylation.

Polyclonal antibodies were raised against pefloxacin, and their specificity to different quinolones was investigated and validated. The results of the competitive indirect enzyme-linked immunosorbent assay (ci-ELISA) demonstrated that the mice anti-pefloxacin antibody could efficiently bind with at least nine quinolones, and to six of them, the cross-reactivity was calculated higher than 65%. Exploiting these antibodies as receptors, six quinolones in fortified eel samples were effectively detected by both ci-ELISA and dot immunogold filtration assay, in which the least detection limit was estimated as ≤ 10 μg/kg and ≤ 20 μg/kg, respectively. These results fit well with molecular modeling studies based on field-overlapping and allow us to suggest possible applications of anti-pefloxacin antibody as a new broad selective receptor for generic assay of quinolones.

Food allergy is increasingly becoming a serious concern these days. With packaged foods becoming the norm of the day, food allergy cases out of accidental consumption are becoming rampant, thereby generating great risks for the subjects involved and prompting food authorities in different countries to formulate new regulations about displaying food allergen data on food labels. Detection of food allergens is conventionally carried out by ELISA or PCR tests. These techniques are limited in that they can only detect one or few allergens at one time. Therefore, in the present study a novel sandwich protein chip assay was developed for quantitation of shrimp allergens in food matrixes. The shrimp allergen model used 3D aldehyde slides as the solid carrier, rabbit antisera as the capture reagent, and biotin-labeled monoclonal antibody as the detector reagent. Resulting antigen–antibody complexes were visualized in the presence of commercial strepavidin labeled with Cy3 to produce fluorescence for quantification. With the LOD of the protein chip being 0.054 mg tropomyosin/kg, the protein chip can quantify down to 0.096 mg tropomyosin/kg. The protein chip was not found to be sensitive to other kinds of foods but cross-reacted to some extent with allergens of some other crustaceans. The recoveries ranged from 69.2 to 99.9%, while the intra- and inter-assay coefficients of variation were <13% and <19%, respectively. It seems that the new assay is reliable enough to detect shrimp allergens in food and food products and help minimize the instances of shrimp allergy. It is also possible to use the protein chip for simultaneous detection of other food allergens.

A new molecular model for quinolone haptens was developed based on molecular field-overlapping. The quanlitive modeling of 3-D conformations showed that the conformation difference among quinolones is caused mainly by the different substitutes at the 1 and 7 positions. The 8-substitute also showed some effect by its inter-reaction with the 1-substitute. The conformational similarity of 27 quinolones to each other was for the first time calculated and exploited for a selection of haptens according to desired broad specificity of corresponding antibodies. The developed model was preliminarily validated with antibodies against different quinolones. A significant positive correlation (R = 0.7793) was observed between calculated overlapping coefficients of haptens and the cross-reactivity of corresponding polyclonal antibodies (Pabs), which confirmed the overall accuracy of the developed model and its application in quantitative structure−activity relationship analysis. On the basis of molecular modeling results, the strategy for the production of broad specific antibodies against quinolones was suggested and the potentiality of several candidates was predicted.

Food allergy is a major health issue worldwide. Mast cells play a very important role in the immediate hypersensitivity for which mast cell degranulation needs to be studied extensively. In this study, an approach was taken to study the characteristics of sensitized mast cell degranulation in vitro, which associated with the study of mast cells and animal models. BALB/c mice were immunized respectively by several food allergens, then blood and peritoneal mast cells were collected at different time points. A dynamic determination was carried out between mast cells and serumal IgE. Comparative analysis on sequential time points showed that there was a close coincidence between mast cell degranulation and IgE antibody titers in sensitized BALB/c mice. Furthermore, it is interesting that sensitized mast cells could implement specific degranulation against the challenges in vitro, but the closely tropomyosins induced mast cell degranulation displayed cross reactions. This is very similar to IgE resisting the allergens in vivo. The study disclosed some characteristics on mast cells, coming from sensitized BALB/c mice, degranulation in vitro.

Acid-solubilised collagen (ASC) was extracted from the skin of Nile tilapia (Oreochromis niloticus) and characterisation was studied. The results indicated that the yield of ASC was 39.4% on the basis of dry weight. This ASC was rich in glycine (35.6%). The amount of imino acids, proline and hydroxyproline, in ASC was 210 residues per 1000 residues. The ultraviolet (UV) absorption spectrum of ASC showed that the distinct absorption was at 220 nm. ASC showed transition curve at maximum temperature (Tmax) of 32.0 °C in 0.05 M acetic acid, about 12 °C lower than that of calf skin collagen. Maximum solubility (0.75 mg/ml) in 0.5 M acetic acid was observed at pH 3. Solubility reached the minimum at pH 7. A sharp decrease in solubility was observed in 2% (w/v) NaCl or above. Biochemical studies indicated that ASC was composed of the α1α2α3 heterotrimers.

Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sargassum graminifolium turn (SG), Sargassum thunbergii (STH), and Laminaria japonica (LJ) from China. The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin, an inhibitor against hyaluronidase. Total phlorotannins contained in the crude extracts were measured as 1.71% (SG), 0.74% (STH), 0.97% (LJ), 3.30% (SC), and 5.06% (ST). The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml, respectively, lower than those of Chinese SG, STH, and LJ (134, 269, and 148 μg/ml, respectively). An antiallergic drug, disodium cromoglycate (DSCG), had an IC50=39 μg/ml, and a natural inhibitor of hyaluronidase, catechin, had an IC50=20 μg/ml. The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml). This suggests that ST is a potent inhibitor of hyaluronidase, indicating a promising future development of natural antiallergic medicines or functional foods.

Food allergy has becoming the serious threat in the world for which the search of an effective anti-allergic drug is the demand of time. Keeping in view of the potentiality of seaweeds, the ethanol extracts from Sargassum tenerrimum (ST), Sargassum cervicorne (SC), and Sargassum graminifolium turn (SG) have been studied in vivo for its antiallergenicity through passive cutaneous anaphylaxis (PCA) and active cutaneous anaphylaxis (ACA) in female BALB/c mice. Intraperitoneal administration of these ethanol extracts inhibit mouse PCA and ACA in a dose-dependent manner using ovalbumin (OVA) and shrimp allergen as triggering agents to induce allergenicity over mice. The extract of ST containing phlorotannin has been found most active over the suppression of PCA triggered by OVA and shrimp with IC50 values of 25.64 and 40.98 mg/kg, respectively and an efficacy comparable to that of an anti-allergic drug disodiumcromoglycate. Similarly, ST inhibits ACA triggered by ova and shrimp allergen in the mouse, with 50% suppression at 25.5 and 43.53 mg/kg, respectively. The results presented here show that these extracts are active on the studied models among which ethanol extract of ST was the most potent, leading toward the promising development of a new class of anti-allergic drugs.