The Fastest Flights in Nature: High-Speed Spore Discharge Mechanisms among Fungi

BACKGROUND: A variety of spore discharge processes have evolved among the fungi. Those with the longest ranges are powered by hydrostatic pressure and include "squirt guns" that are most common in the Ascomycota and Zygomycota. In these fungi, fluid-filled stalks that support single spores or spore-filled sporangia, or cells called asci that contain multiple spores, are pressurized by osmosis. Because spores are discharged at such high speeds, most of the information on launch processes from previous studies has been inferred from mathematical models and is subject to a number of errors. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we have used ultra-high-speed video cameras running at maximum frame rates of 250,000 fps to analyze the entire launch process in four species of fungi that grow on the dung of herbivores. For the first time we have direct measurements of launch speeds and empirical estimates of acceleration in these fungi. Launch speeds ranged from 2 to 25 m s(-1) and corresponding accelerations of 20,000 to 180,000 g propelled spores over distances of up to 2.5 meters. In addition, quantitative spectroscopic methods were used to identify the organic and inorganic osmolytes responsible for generating the turgor pressures that drive spore discharge. CONCLUSIONS/SIGNIFICANCE: The new video data allowed us to test different models for the effect of viscous drag and identify errors in the previous approaches to modeling spore motion. The spectroscopic data show that high speed spore discharge mechanisms in fungi are powered by the same levels of turgor pressure that are characteristic of fungal hyphae and do not require any special mechanisms of osmolyte accumulation

Fermentation and valorization of watermelon (Citrullus lanatus) rind wastes into livestock feed using Aspergillus niger and Mucor sp.

Agro-industrial wastes pose environmental health hazards to humans and animals; yet, they are abundant, readily availabile and cheap, and therefore provide opportunities for their valorization with microorganisms to produce value-added, nutrient-rich animal feed. This study (i) determined, in vitro, optimum growth conditions for Aspergillus niger and Mucor sp. and (ii) subsequently evaluated their ability to ferment and valorize watermelon wastes for protein enhancement. Changes in protein contents of sterilized and unsterilized watermelon substrates were determined after 5, 10, and 15 days of fermentation with mono- and co-cultures of A. niger and Mucor sp. at 25 °C. Different growth conditions (pH, temperature, different concentrations of ammonium nitrate, sodium nitrate, urea, sodium chloride and thiamine) of synthetic media variously supported mycelial growth of A. niger and Mucor sp., either as mono- or co-culture; optimum growth conditions were selected for fermentation of watermelon wastes. Protein contents of sterilized and unsterilized watermelon substrates were enhanced by fermentation: (i) percentage increase in protein contents of sterilized watermelon fermented with mono-cultures of A. niger, Mucor sp. and co-culture of A. niger and Mucor sp. were 35.91, 18.94 and 22.18 %, respectively; (ii) protein contents in unsterilized watermelon substrates also increased by 23.94, 9.49, and 14.88 % for mono-cultures of A. niger and Mucor sp. and their co-culture, respectively. Overall, the observed trend in the increase of protein contents in the sterilized and unsterilized substrates by the test fungi was: mono-culture of A. niger > co-culture of A. niger and Mucor sp. > mono-culture of Mucor sp. Crude fat, fiber and ash contents significantly (p ≤ 0.05) decreased in both sterilized and unsterilized watermelon substrates, whereas the carbohydrate content increased significantly (p ≤ 0.05) in the substrates. These findings highlight the potential of watermelon waste as valuable bioresource and feedstock for valorization into livestock feed through fungal biotechnology. Future works to augment findings are suggested

Valorization of agro-industrial wastes into animal feed through microbial fermentation: A review of the global and Ghanaian case

Agricultural and industrial activities around the world lead to the production of large quantities of agro-industrial wastes (e.g., peels of cassava, pineapple, plantain, banana, and yam, as well as rice husks, rice bran , corn husks, corn cobs, palm kernel cake, soybean meal, wheat bran, etc.). These agro-industrial wastes are discarded indiscriminately, thereby polluting the environment and becoming hazardous to human and animal health. Solid-state fermentation (SSF), a microbial fermentation process, is a viable, efficient approach that transforms discarded agro-industrial wastes into a plethora of useful value-added bioproducts. There is growing interest in the application of SSF in valorizing agro-industrial wastes for the production of fermented, protein-rich animal feed within the livestock industry. SSF reduces anti-nutritional factors whose presence hinders the digestibility and bioavailability of nutrients in agro-industrial wastes. Thus, the application of SSF improves the nutrient contents and quality of valorized agro-industrial wastes as animal feed. Fermented animal feed production may be safer, cheaper and enhance the overall growth performance and health of animals. SSF, therefore, as a strategic approach in a circular bioeconomy, presents economic and practical advantages that guarantee efficient recycling and valorization of agro-industrial wastes that ameliorate environmental pollution. This paper reviews the status of global and local Ghanaian biotransformation and valorization of agro-industrial wastes through SSF for the production of nutrient-rich animal feed

Towards genetically engineered crops in Ghanaian agriculture : confined field trials and the 'next-door neighbor effect' theory

Genetically engineered (GE) crops have a role to play in increasing agricultural productivity. However, efforts to promote genetic engineering agriculture in Africa have been met with some amount of resistance. Here, we report recent efforts to promote GE agriculture in Ghana, a West African nation considered one of Africa's model democracies and growing economies. Ghana is currently running confined field trials of some selected GE crops, but analysis of ongoing genetically modified organism (GMO) debates and published opinions shows a considerable amount of opposition to GE agriculture and GMOs in Ghana. This notwithstanding, we suggest that Bt cotton cultivation in Burkina Faso--Ghana's immediate neighbor to the north--may play a role in eventually putting Ghana on the map of GE agriculture countries, a phenomenon reported elsewhere which we have described in this article as the 'next-door neighbor effect.' The biosafety implications of the 'next-door neighbor effect' are also discussed here. We conclude that the 'next-door neighbor effect'--in addition to corporate and political interests--will explain the entry of GE crops into some new markets