Genetic structure and gene flow of Anopheles minimus and Anopheles harrisoni in Kanchanaburi Province, Thailand

Isozyme frequencies were compared in seven field collections of Anopheles minimus complex using starch gel electrophoresis. Mosquito collections were sampled from four districts in Kanchanaburi Province where malaria is endemic. From eight enzyme systems, nine loci and seven polymorphisms were detected, indicating limited genetic differentiation among the seven collections (F-ST = 0.061). The highest percent polymorphic loci were observed in Bong Ti Noi (BTN) Village (55.6%), whereas the least percent polymorphism was seen in Tha Kradan (TK) Village (22.2%). Comparing villages Pra Jedee (PJ) with Pu Teuy C (PTC) and Huai Khayeng (HK) with Pra Jedee (PJ), gene flow among collections varied from 3.72 to 62.25 reproductive migrants per generation. Among the seven collections, no correlation was seen between genetic and geographical distances (P > 0.05). Anopheles minimus (former species A) and Anopheles harrisoni (former species Q from Pu Teuy fit most closely in the same cluster, possibly indicating relatively recent divergence between taxa. The genetic and epidemiological ramifications of these findings are discussed

Oocyte differentiation and reproductive health of solitary tunicate (Styela plicata) from Eastern Coast of Thailand

Histopathological examination is a widely acknowledged technique to assess the reproductive health of aquatic organisms, but it has never been applied to the tunicate Styela plicata, a potential indicator species of water quality. In this study, we examined the oocyte differentiation of S. plicata obtained from the eastern coast of the Gulf of Thailand in order to provide basic information for future assessment of its reproductive health. The mature gonad of S. plicata comprised several ovo-testicular convoluted tubes, in which each tube was divided into apical and terminal portions. The ovarian tissue is located in the apical part of the tunicate body and contained oocytes of various differentiation stages (asynchronous development type) consisting of the four phases namely oogonial proliferation phase, primary growth phase, secondary growth phase (secondary growth and full-growth stages), and post-ovulatory phase. Changes in the morphology of oocytes and follicular cells were described for each differentiation stage. In addition, we unexpectedly observed a high prevalence of atretic follicles (24.5%), which might indicate the oocyte damage by environmental stresses. These findings would be useful for future assessment of reproductive histology of S. plicata and other tunicate species from environmental perspectives

Bioactive compounds content and their biological properties of acetone extract of <i>Cuscuta reflexa</i> Roxb. grown on various host plants

<p>The present study is aimed to evaluate the total phenolic and flavonoid contents, and free phenolic compounds of acetone extract of <i>Cuscuta reflexa</i> grown on five different hosts: <i>Coccinia grandis</i>, <i>Ficus racemosa</i>, <i>Samanea saman</i>, <i>Streblus asper</i> and <i>Zollingeria dongnaiensis</i>, and to explore the antioxidant activities, α-glucosidase and tyrosinase inhibitory properties of the extracts. The highest level of total phenolic and flavonoid contents were observed in the extract of <i>C. reflexa</i> that was grown on <i>S. asper</i> (65.45 mg GAE/g extract) and <i>C. grandis</i> (97.83 mg QE/g extract), respectively. According to HPLC results, vanillic acid, rutin and quercetin were found in all extracts of <i>C. reflexa</i> grown on diversified hosts. The extract of <i>C. reflexa</i> grown on <i>C. grandis</i> possessed the greatest antioxidant activities (DPPH; 251.64 μg/mL, FRAP; 26.44 mg GAE/g extract), α-glucosidase inhibition accounted for 84.36 per cent and antityrosinase activity was at 18.29 mg KAE/g sample.</p