## 3 Results and Discussion
### Physiological Profiles of Bacteria in Vermicasts  
The AWCD and H indices of bacterial communities of PL (1.996 A\({}_{\rm 590 nm}\); 3.328 A\({}_{\rm 590 nm}\)) were significantly higher (\(p<0.05\)) than those of EE (1.042 A\({}_{\rm 590 nm}\); 3.216 A\({}_{\rm 590 nm}\)) (Figure 6). The richness index showed that the bacterial communities in both vermicasts utilized all 31 carbon substrates. CSUPs (Figures 7 and 8) of the two earthworm species showed that the bacterial communities in PL have significantly higher (\(p<0.05\)) utilization of amines and amides (1.172 A\({}_{\rm 590 nm}\); phenylethylamine), phenolic compounds (1.088 A\({}_{\rm 590 nm}\); 2-hydroxy benzoic acid,) polymers (1.067 A\({}_{\rm 590 nm}\); tweeen 80 and alpha-cyclodextrinrith), and carboxylic and acetic acids (1.047 A\({}_{\rm 590 nm}\); D-galacturonic acid). On the other hand, significantly higher (\(p<0.05\)) utilization of carbohydrates (1.160 A\({}_{\rm 590 nm}\); N-acetyl-D-glucosamine, D-mannitol,  
Figure 5: Dominant bacterial genera (**a**) and species (**b**) in _P. loshuosensis_ (PL) and _E. eugeniae_ (EE) vermicasts generated by QIME-UCLUST.  
Community-level physiological profiling allows the assessment of the functional diversity or metabolic potential of a microbial community as represented by carbon substrate utilization. The oxidative ability of a microbial community is indicated by the AWCD values in relation to the R index, signifying the number of oxidized substrates [48]. PL bacterial communities (1.996 A\({}_{\rm 590 nm}\)) showed higher AWCD values denoting their oxidative ability compared to EE (1.796 A\({}_{\rm 590 nm}\)), but both were able to oxidize all carbon substrates with an R value of 31. On the other hand, the H index measures the diversity of substrate utilization (DSU) in relation to the efficiency of microorganisms in substrate degradation [49]. Thus, a higher H value (3.356 A\({}_{\rm 590 nm}\)) confirmed that bacterial communities present in PL were more efficient in the degradation of carbon substrates. These results show that bacterial  
Figure 6: Average well-color development (AWCD), richness (R), and Shannon–Weaver index (H) of carbon substrate utilization by _P. losbanosensis_ (PL) and _E. eugeniae_ (EE) vermicasts’ bacterial communities after 48 h of incubation (n = 3). Vertical bars represent the standard error of the mean. Means separated by different letters are significantly different ([PERSON]’s mean separation test, \(p\) < 0.05).  
Figure 7: Carbon substrate utilization patterns (CSUPs) of _P. losbanosensis_ (PL) and _E. eugeniae_ (EE) vermicasts’ bacterial communities after 48 h of incubation (n = 3). Vertical bars represent the standard error of the mean. Means separated by different letters are significantly different ([PERSON]’s mean separation test, \(p\) < 0.05).  
communities associated with the vermicasts of _P. losbanosensis_ with higher AWCD, R, and H indices possess higher functional diversity or metabolic potential [38].  
To date, little is known about the physiological profiles of bacteria in earthworm vermicasts, except in the case of _Lumbricidae_ earthworms such as _Allolobophora chlorotica_ [PERSON], 1826, _A. caliginosa_, and _L. terrestris_, which were reported to accelerate functional diversity in their vermicasts [50]. Their vermicasts had an AWCD value of 0.94 A\({}_{590\mathrm{nm}}\), which was significantly higher than the bulk soil and transitional zone (0.11-0.12 A\({}_{590\mathrm{nm}}\)) of their burrow system. Moreover, groups of carbon substrates such as amino acids, carboxylic  
Figure 8: Carbon substrate utilization patterns (CSUPs) of _P. losbanosensis_ (PL) and _E. eugeniaae_ (EE) vermicasts’ bacterial communities after 48 h of incubation (n = 3).  
acids, carbohydrates, polymers, and miscellaneous compounds were favored in vermicasts and burrow systems as compared to bulk soil.