SummaryVitrification is a simple and cost-effective method for the storage of human spermatozoa without the use of conventional cryoprotectants, by plunging the sperm suspension directly into liquid nitrogen. As a result, solidification of living cells without the formation of ice crystals is achieved during cooling. This study aimed to compare cryoprotectant-free vitrification to conventional cryopreservation protocols. Semen samples (n = 35) were collected from patients seeking diagnostic assistance at the Reproductive and Endocrine Unit at Steve Biko Academic Hospital. Samples were processed using a discontinu-ous density-gradient centrifugation method. Washed samples were split into two aliquots and cryopreserved either by means of cryoprotectant-free vitrifica-tion (sucrose + 1% albumin) or conventional slow freezing (TEST-yolk buf-fer). Post-thawing, the sperm motion parameters, mitochondrial membrane potential (Dwm) and DNA fragmentation were compared between the two groups. No significant differences were observed in the sperm motility parame-ters (P > 0.05). Significantly higher percentages of Dwm (11.99% AE 4.326%versus 6.58% AE 1.026%; P < 0.001) and lower percentages of DNA fragmenta-tion (2.79% AE 1.017% versus 3.86% AE 1.38%; P < 0.01) were observed when comparing cryoprotectant-free vitrification to conventional cryopreservation. Cryoprotectant-free vitrification is a rapid and promising alternative to conventional methods resulting in good-quality spermatozoa post-thaw.
Sainfoin (Onobrychis viciifolia), is a beneficial forage legume, which is adapted to a wide range of climatic conditions. It has the potential to be an exceptionally useful forage crop due to its high digestibility and palatability, anthelmintic properties, endophytes, and abundance of nectar and pollen for honey production. We report here the first attempts to study the diversity of endophytic fungi and bacteria associated with sainfoin in South African agricultural lands during dry and wet season.. This was achieved by isolating, cultivating, purifying, and molecular characterising the fungi and bacteria from the roots of sainfoin obtained from an established agricultural field during both the wet and dry seasons. During the dry season, 15 fungal isolates and 10 bacterial isolates were obtained from sainfoin roots, which consisted of 9 fungal genera and 4 bacterial genera, respectively. While, during the wet season 28 fungal isolates and 24 bacterial isolates, representing 12 fungal genera and 12 bacterial genera were successfully isolated. A comprehensive literature-based discussion on the potential plant growth-promoting effects of the obtained fungal and bacterial isolates was also conducted to preliminary identify those with potential for agricultural application. The study showed that sainfoin roots could interact with a diverse group of endophytes, which is greatly influenced by seasonality, with a higher diversity and isolation rate during the wet season in South Africa.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations –citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.