Tuberculosis is highly contagious disease that can be transmitted between humans and animals. Asian elephants ( Elephas maximus ) in captivity live in close contact with humans in many Asian countries. In this study, we developed an interferon gamma release assay (IGRA) for elephant TB detection using antigens from the MTB complex (MTBC) and nontuberculous mycobacteria (NTM) as stimulating antigens (PPD, ESAT6, CFP10) to elicit a cell-mediated immune response (CMIR). The developed assay was applied to an elephant herd of more than 60 animals in Thailand, and the results were compared with those obtained through serological detection. IGRA has sufficient sensitivity for detecting elephant interferon gamma (eIFNγ) from specific antigen-stimulated PBMCs. Among 60 animals tested, 20 samples (33.3%) showed negative results for both MTBC and NTM infection. Eighteen samples (30%) showed positive responses against PPD from M. bovis and/or ESAT6 and CFP10, indicating MTBC infection. In contrast, only 15.6% showed seropositivity in a commercial serological test kit for elephant TB. The discrepancies between serological and CMIR highlight that the two methods may detect different stages of elephant TB. Therefore, employing both tests may enable them to complement each other in correctly identifying elephants that have been exposed to MTBC.

A new biphenyl, named schomburgbiphenyl (1), and 14 known compounds were isolated from the wood of Garcinia schomburgkiana. The known constituents were identified as follows: three xanthones (2, 8 and 9), two benzophenones (3 and 4), three biphenyls (5-7), three biflavonoids (10-12) and three steroids. Compounds 3 and 4 were highly cytotoxic to SW620 cell line (100 times more than the positive control, doxorubicin) and were also strongly active against KATO-III, HepG2 and CHAGO cell lines. Compound 6 was specifically cytotoxic towards SW620 cells, whereas compound 8 displayed strong cytotoxicity against all five cell lines tested.

Aflatoxin M1 (AFM1), a group I carcinogen, can be found in the milk of animals fed with aflatoxin-B 1-contaminated feedstuff. In this study, we developed and validated a lateral flow immunoassay (LFIA) with the cutoff value of 0.5 μg/L for AFM1 screening. The validation revealed that the assay yielded high sensitivity, selectivity and efficiency with no false positives. Forty-one commercial milk samples were tested for AFM1 by the developed LFIA. However, the developed LFIA could not be applied to milk samples flavoured with chocolate and coffee. Otherwise, all samples gave negative test results.

In this study, a monoclonal antibody (mAb) against chlortetracycline was prepared by immunisation using chlortetracycline conjugated to bovine serum albumin (CTC-BSA) and cell fusion. One monoclonal antibody (1-2B) against chlortetracycline was obtained with an IC 50 of 0.33 ng/ml and a detection limit of 0.1 ng/ml. The cross reactivity of this antibody with structurally related and nonrelated compounds was less than 0.1%, demonstrating that the obtained mAb provided high specificity. Under optimal conditions for ic-ELISA, a linearity was obtained between 0.06 and 3.9 ng/ml of chlortetracycline. The quantification of CTC-spiked milk and honey samples was also performed, demonstrating recovery rates ranging from 95.2% to 105.6% and the coefficient of variation below 10% for both intra-and inter-variation assays. Based on the sensitivity and specificity measurement, mAb 1-2B could feasibility be used as a screening tool for CTC residue detection in milk and honey samples.

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