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• The abortive rate of ovules could go as high as 94 % in an ovary of Castanea mollissima , the occurrence of abortive ovules with abnormal structure was related to the obstruction of nutrient transport. • Abortive ovules exhibit the presence of starch grains at an earlier stage than fertile ovules. • Cytological features proved that the selective death of ovules was dependent on programmed cell death. Chinese chestnut (Castanea mollissima Blume.) ovary contains 12–18 ovules, but only one can develop and grow normally, which indicates that the abortive rate of ovules can go as high as 94 %. In this study, we observed the developmental characteristics and cytological changes of abortive ovules and fertile ovules during development. Morphological analysis showed it would take about 15∼20 days from globular to cotyledon embryo in fertile ovules, which is accompanied with the formation and apoptosis of endosperm. But there were stark differences in the nutrient transport, microstructure and ultrastructure of fertile and abortive ovules. The fluorescence disodium fluorescein and FDA indicated that all ovules were viable at early stages, but some ovules became inactive at different times as the ovary developed. Fluorescence labelling and ultrastructure showed cell nuclei of abortive ovules were disintegrated at 25 days after anthesis (DAA). Compared with the fertile ovules, starch grains were synthesized at earlier periods, but disappeared immediately, and the cells were usually irregular in shape, and had folded cell membranes in the abortive ovules. Furthermore, the Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was carried out to assess programmed cell death in fertile and abortive ovules, results showed that DNA fragmentation was occurred in the cells of abortive ovules. In short, these results provide new insights into ovule abortion in the angiosperm. [ABSTRACT FROM AUTHOR]

Abstract A 1,6-α-D-glucan (CPA) with a high molecular weight of 2.0 × 103 kDa was isolated from the fruits of Castanea mollissima Blume. CPA showed good water solubility, low side effects on normal cells, and moderate cytotoxicity on cancer cells. Selenium nanoparticles (SeNPs) possess significant anticancer effects, but poor water solubility and dispersity. Therefore, an effective nanocomposite was designed in order to enhance the stability and anticancer effects of SeNPs decorated with CPA. Water soluble and dispersed selenium nanoparticles (CPA-SeNPs) were fabricated using CPA and Na 2 SeO 3 by redox reaction with ascorbic acid. The average diameter of CPA-SeNPs was 53.7 ± 4.0 with a Se content of approximately 171.4 mg/g. CPA-SeNPs showed a significant anti-proliferative effect on HeLa cells in vitro. Since these NPs could induce apoptosis and S phase arrest. The apoptotic pathway triggered by CPA-SeNPs on HeLa cells was also characterized as induced by reactive oxygen species (ROS) overproduction, mitochondrial dysfunction and activation of caspase-3. This study suggested that CPA-SeNPs could be developed as a potential candidate in cancer treatment, especially against human cervical cancer. Highlights • CPA-SeNPs was fabricated using CPA and Na 2 SeO 3 by reducing with ascorbic acid. • CPA-SeNPs was approximately 50 nm with a Se content about 171.4 mg/g. • CPA-SeNPs showed a significant anti-proliferative effect on HeLa cells in vitro. • CPA-SeNPs induced HeLa cells apoptosis in an intrinsic apoptosis pathway. [ABSTRACT FROM AUTHOR]

The present study aimed to characterize the glucan from C. mollissima Blume fruits and its selenium derivative, then investigate their antitumor activity in vitro. A glucan, designated as CPA, was firstly isolated from the fruits of C. mollissima Blume. Structure analysis indicated that CPA was a linear 1,6-α-D-glucan with the average molecular weight about 2.0 × 10 kDa. The selenylation modification derivative of CPA (sCPA), exhibited a stronger antiproliferative effect on tumor cells than CPA in vitro. CPA and sCPA could induce HeLa cells apoptosis and decrease mitochondrial membrane potential. sCPA could also arrest HeLa cells in S phase, promote reactive oxygen species generation and activate caspase-3 activity in HeLa cells. These results manifest that CPA and sCPA inhibit the proliferation of HeLa cells via different mechanisms, which is meaningful for their potential use as antitumor drugs. [ABSTRACT FROM AUTHOR]