Mascarocoffea are wild coffee plants endemic to Madagascar. These plants produce diverse, often specific biomolecules that are not found in cultivated coffee plants. Production of these compounds could be due to interactions between the endophytes and the host plant. Few studies have been carried out on the richness and diversity of microorganisms associated with these coffee plants. The objective of this study was to identify endophytic fungi isolated from the leaves of species of Mascarocoffea by morphological and molecular methods. Fifteen taxa were morphologically identified among the 30 isolated. These included Phyllosticta sp., Colletotrichum sp., Daldinia sp., Diaporthe sp., Cladosporium sp., Fusarium sp.01, Fusarium sp. 02, Fusarium sp. 03, Monilinia sp., Trichoderma sp., Alternaria sp, Penicillium sp., Aspergillus niger, Rhizopus sp. and Nigrospora sp. The phylum Ascomycota was the most represented, with 14 taxa and 1 taxon (Rhizopus sp.) belonging to the phylum of Zygomycota. Molecular characterisation confirmed of the identity of these 15 taxa and those of the morphologically Unidentified (NI) mycotaxa including Colletotrichum karstii, Colletotrichum siamense, Neofusicoccum parvum, Colletotrichum siamense, Punctularia strigosozonata, Stemphylium solani, Phoma multirostrata, Calophoma complonata, Daldinia vanderguchtiae, Phoma exigua and Boremia exigua. This study allowed us to identify the endophytic fungi isolated from Mascarocoffea leaves from Madagascar.

Concrete is at a high risk of cracking which threats its durability. Self-healing bacterial concrete has been developed in recent years to tackle this issue and its effectiveness has been massively studied. However, bacteria need carriers and expanded clay is the most used as such, but it reduces concrete strength. Moreover, bacterial culture and immobilization processes are highly expensive; calcium salts also contribute to the high cost of this type of concrete. This work therefore aims to overcome these limitations. Calcium salts were collected from the chitosan production process from crab waste. In addition, we noticed that Betafo pozzolan contains an abundant number of microorganisms, and for the first time, we discovered that those microorganisms have polyextremophilic characters, are resistant to various sterilization methods, and allow the self-healing concrete process. We concluded that calcium salts from the crab, with those microorganisms are able to heal crack up to 350 µm wide, reducing the expenses related to nutrients, and eliminating those related to the growth and the immobilization of bacteria on carrier. Moreover, we pointed out that pozzolan significantly increases compressive strength by 90.04%. However, the behavior of those microorganisms and the pozzolanic reactions need to be further investigated.

Seafood wastes raise environmental concerns and many studies focus on recycling those wastes into chitosan. However, the environmental impact of that process is underestimated. Indeed, a significant amount of toxic wastes is released, potentially harmful to humans and the environment. This study therefore focuses on reducing of that adverse impact by recycling the waste produced during the first step of the production of chitosan: demineralization. By varying the concentration of the acid while keeping stoichiometric ratios, it was shown that the concentration plays a vital role in the efficiency of the demineralization and the purity of the salts. This effect of the concentration on such reaction is still poorly investigated and this study thus offers a deeper knowledge to the chitosan research. Moreover, it was concluded that calcium salts from the transformation of crab wastes into chitosan can be collected and reused. Nevertheless, studies about recycling waste from the other steps of the chitosan production are needed to reduce this process’s environmental impact even more.

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