National Chung Cheng University developed a bamboo charcoal probiotics formula to boost aquaculture production
Jul 27, 2022
When it comes to bamboo charcoal, most people may only be familiar with its ability to deodorize or filter out impurities in the water, and do not know much about its other possibilities. The coming-up story shall be one of many examples to change the mind of people over the uses of bamboo charcoal. Recently, Dr. Shau-Chun Wang, a professor from the Department of Chemistry and Biochemistry at National Chung Cheng University (CCU) developed a probiotic formula utilizing the characteristics of bamboo charcoal, in cooperation with local aquaculture farmers in Chiayi, to tackle the tasks in aquafarming. According to the findings, the bamboo charcoal probiotics formula developed by the CCU team and its biochar technology can help improve the water quality of the ponds for white shrimp (Litopenaeus vannamei) farming and double up the yield of shrimp production in the same harvest season, without causing any harm to the environment. At present, the technology patent applied by the CCU team has been officially approved, making it possible for the fishery and electricity symbiosis in the near future with a win-win situation of combining aquafarming and photovoltaics in the circular economy.
\"The technology commonly used in environmental water purification and aquaculture is called \'bio-flocculation\', in which the microorganisms such as probiotics are cultivated on the alum colloidal materials and then released back into the water body.\" Professor Wang said that the chemical substance alum that is traditionally used for bio-flocculation contains aluminum compounds. Although this substance itself is not particularly toxic, the accumulated effect may be harmful for human body and the environment in the long run, because other toxic heavy metals may be attached to it while adsorbing free-living microorganisms. Yet, when the filter feeders such as the Meretrix clams accidentally or non-discriminatively feed on these bioflocs, they may also absorb the toxic heavy metals among the alum, which could end up on the table for human consumption.
The story of developing the bamboo charcoal probiotics formula to tackle issues in aquafarming can date back to four years ago, when a low-pressure system brought a disastrous flood that severely damaged the aquaculture industry in the Chiayi area. From 23 to 26 August 2018, the large amounts of rainwater brought by that windstorm changed the salinity and the environment of the fish farms entirely. In order to help local aquaculture farmers to recover from the damages, better their farming conducts and reduce the use of chemical agents, the CCU team initiated a promotion of the probiotics ecological water purification method. However, concerning to the cost of probiotic bacteria culture is relatively high due to its need for a large amount of molasses, which is uneconomical for the aquaculture industry, the team had to take the alternative approach to complete the tasks. Therefore, the CCU team came up with a new idea to research and develop the easy-to-use, low-cost \"bamboo charcoal probiotic formula\" in bio-flocculation that can be used for aquaculture water purification.
Professor Wang indicated that bamboo charcoal is a typical type of biochar with a considerable number of micro-nano pores, and the pore size and distribution are particularly suitable for the cultivation of probiotics. \"Not only does it allow microorganisms to find a place to settle, but it also adsorbs nutrients that the microorganisms need.\" In a documented experiment, the CCU team ground the bamboo charcoal into charcoal powder and dissolved it into the probiotic solution, and then adjusted the ratio of the mixed liquid through several experimental tests. With the formula designed by the team, the team found that the microorganisms could grow faster and more densely than the traditional alum culture in less than a week. In addition, by using this technology, the bioflocs can be formed by the growth of the microorganisms themselves without absorbing any heavy metal. Hence, it shall be free from any concerns of heavy metal accumulation in the food chain for human consumption.
The biochar presents a semi-floating status in water owing to its delicate particles, it can not only be used as a source of nutrients, but also be used to elevate the survival rate in aquaculture. Wang pointed out that because of the domestic shortage of parental white shrimps for shrimplets supplies, some aquaculture farmers might attempt to import parental shrimps from overseas. Yet, the imported parental shrimps may not be suitable for the environmental conditions of domestic aquaculture. Furthermore, aquaculture farmers in Taiwan commonly apply the open-air and high-density farming style to rear the shrimps, which can often speed up the disease transmission between shrimps. As a result, the white shrimps, a species whose resistance to pathogenic diseases is essentially poor, are more likely to die when they were introduced into such environment, affecting the future shrimp production. This is the challenges faced by the farmers in this industry and might be dealt with positively through the application of bamboo charcoal probiotics formula.
At present, the CCU team has partnered with five local white shrimp farmers through the collaboration with the Agriculture Department in Chiayi County and Taiwan Aquaculture Development Association. In the cooperation with the farmers, the CCU team completed the probiotics culture first, then introduced it to the shrimp farms and showed the farmers how to prepare the bamboo charcoal probiotics formula and how to apply it to help grow the probiotics for the later usage. Wang said that the significantly increasing survival rates and quality of the white shrimps from partnered fish farms were demonstrated by the actual implementation. The survival rate in those cooperated farms can reach as high as nearly 40%, which is more than double that of other farmers\' survival rate.
The CCU team developed the bamboo charcoal probiotics formula through the cross-disciplinary collaboration which was facilitated by the \"University Social Responsibility Projects\" promoted by the Ministry of Education, to help stabilize the water quality of local aquaculture. Wang stated that these partnered fish farms often mixed cultures of several different types of species including tilapia, flathead grey mullet, Meretrix clams, milkfish, etc. The statistics showed that all species reared in the farms are all benefited by the conduct with remarkable harvest outcomes. Presently, the technology has been successfully patented. The CCU team also managed to set up a living lab at Tranquil Lake in CCU, allowing staff members and students to learn about the functionality of the biochar-based water treatment system. In addition to the possibility of applying the technology to the field of fishery and electricity symbiosis, it can also be used to increase the efficiency of bamboo debris recycling as it is recently in progress under the researches funded by the Foundation of Taiwan Sugar Association, improving bamboo economic efficiency.