Industrial valorization of garlic (allium sativum l.) under the effect of endemic microbial bioinputs

Abstract

Garlic (Allium sativum L.) is an aromatic herbaceous cultivated for culinary and medicinal purposes. The industrial sector requires a high level of consistency in the biomass, flavor and nutritional profile of garlic. Which can prove challenging to achieve across variable growing conditions due to the impact of soil quality, climate and crop management practices on garlic yield and quality. In order to increase the value of this plant in the pharmaceutical and agricultural sectors, our study was based on the cultivation of garlic in pots and under greenhouse using microbial bio-inputs, including two isolates of arbuscular mycorrhizal fungi, three isolates of Trichoderma asperellum and one isolate of Plant growth–promoting rhizobacteria (PGPR), a comprehensive analysis was conducted on a number of parameters including, growth, yield, secondary metabolites, antioxidant, antimicrobial and herbicidal potential of aqueous extracts prepared from each of the garlic plant samples. The findings of this study indicate that the inoculation of garlic with endemic microorganisms exerts a range of effects on growth parameters, functional groups of chemical compounds and the antioxidant and antimicrobial properties of their extracts. The results obtained highlight the significance of employing endemic microbial isolates (T1) Trichoderma asperellum, (T7) PGPR and (MO) arbuscular mycorrhizal fungi to enhance the majority of the growth parameters under investigation. Moreover, the application of the mycorrhizal fungus isolate MO and the Trichoderma asperellum isolate T3 resulted in an enhancement of the quality of the secondary metabolites of this crop, as well as an increase in the antioxidant and antimicrobial properties of their aqueous extracts. Furthermore, the aqueous extract prepared from garlic plants inoculated with isolate T3 indicated a potential inhibitory effect on seed germination and the growth of Lolium perenne seedlings. In a similar manner, the aqueous extract prepared from garlic plants inoculated with the isolate T3 exhibited most notable antimicrobial properties, with this potential being retained even in the freeze-dried form for a period of six months. In light of these findings, a series of pharmaceutical products were formulated, encompassing both antimicrobial capsules and a gel, for both oral and cutaneous administration.