Table 2.

Organic acids secreted by PSM.

PSM	Organic acids	References
Phosphate solubilizing bacteria
Bacillus, Burkholderia, Paenibacillus sp.	Gluconic, oxalic, citric, tartaric, succinic, formic, and acetic acid	Chawngthu et al., 2020
Pantoea, Pseudomonas, Serratia, and Enterobacter	Oxalic, citric, gluconic succinic, and fumaric acids	Rfaki et al., 2020
Bacillus sp. strain AZ17	Pyruvic, succinic, fumaric, malic, tartaric, and oxalic acids	Zúñiga-Silgado et al., 2020
Pseudomonas sp. strain AZ5, Bacillus sp. strain AZ17	Acetic, oxalic and gluconic acids, acetic, citric, and lactic acids	Zaheer et al., 2019
Phosphate solubilizing fungi
Rhizopus stolonifer and R. oryzae	Oxalic, lactic, citric, succinic, gluconic, malic, fumaric, acetic acid, and propionic acids	Mohammed, 2020
Trichoderma and Aspergillus	Oxalic, citric, formic, tartaric, malic, acetic, and citric acids	Li et al., 2016
Penicillium oxalicum and A. niger	Gluconic acid, oxalic, propionic, and malic acids	Li et al., 2016
Phosphate solubilizing actinomycetes
Streptomyces sp. KP109810, Streptomyces sp. CTM396	Gluconic acid	Farhat et al., 2015