# Cleaner Processes for Making Laundry Soap from Vegetable Oils and an Essential Oil
## 3 Results and Discussion
### Antimicrobial Capacity  
The determination of the total number of germs/products is made by a quantitative method and the results are shown in Figures 12 and 13 and expressed quantitatively in Table 7. Antimicrobial efficacy testing is conducted by assessing the ability of microorganisms to attach to and persist on the sample surface upon contact. Essentially, each sample serves as a potential support for bacterial biofilm formation.  
The sample is immersed in physiological saline, where vortexing is used to release any saprophytic microorganisms that may be present in the or on the textile sample at that moment. The resulting suspension is then introduced into Mueller-Hinton Agar, a culture medium recommended by international standards (EUCAST, CLSI) for antimicrobial testing.  
By incorporating the suspension into the agar medium--melted, cooled to 45 \({}^{\circ}\)C, and homogenized with the vortexed suspension--the conditions are optimized for the growth of all potential microorganisms present on the sample surface. The absence of microbial growth confirms the efficacy of the applied treatments, which prevents microbial colonization and development on the textile sample surfaces.  
\begin{table}
\begin{tabular}{c c} \hline
**CFU */Sample 3 \(\times\) 3 cm/mL Washing Suspension** \\ \hline
**Soap Code** & **CFU * \\
**(Number on the Lid)** & \\ \hline CS1 (1R) & 0 \\ CS2 (2R) & 0 \\ CS3 (3R) & 0 \\ CS4 (4R) & 0 \\ HS1 (1C) & 1 \\ HS2 (2C) & 0 \\ HS3 (3C) & 0 \\ HS4 (4C) & 0 \\ \hline \end{tabular}  
* CFU = Colony-Forming Units (Colony-Forming Units/sample 3 \(\times\) 3 cm/mL washing suspension).  
\end{table}
Table 7: Results of antimicrobial analysis expressed in Colony-Forming Units (CFUs).  
Figure 12: The results obtained after incubating for 48 h at 37 \({}^{\circ}\)C of textile samples washed with hot-formulated soaps, HS1–HS4 (**a**), coded as 1C–4C on the lids (**b**).  
Figure 13: The results obtained after incubating for 48 h, at 37 \({}^{\circ}\)C of the textile samples washed with cold-formulated soaps, CS1–CS4 (**a**) coded as 1R–4R on the lids (**b**).  
The treatments applied to the test samples imprint the textile matrices' physicochemical properties that do not favor microbial multiplication. However, the exception is the sample washed with the HS1 standard soap (without essential oil, code 1C (on the lid) in Figure 12; 1 CFU/mL washing suspension). In the HS1 case, the explanation takes into account the long saponification time (1 h) at 100 \({}^{\circ}\)C, which may reduce the antioxidant and antimicrobial properties of olive oil during saponification. In contrast, in the case of CS1, the low cold saponification temperature (30 \({}^{\circ}\)C) does not affect the components responsible for the antimicrobial effects (polyphenols, lauric acid and vitamin E).  
For comparison, the testing of the soaps formulated by hot/cold saponification, from 100% olive oil and 100% coconut oil, showed that all have antimicrobial effects, except for the soap consisting of 100% olive oil from hot saponification (the result being 1 CFU/mL washing suspension). HM soap formulated by hot saponification with 100% olive oil allows for the multiplication of microbes because prolonged exposure to 100 \({}^{\circ}\)C causes the degradation of the oil and, consequently, cancels the slight antimicrobial activity that olive oil normally possesses. In the case of HC soap, hot processed from 100% coconut oil, thermal degradation cannot cancel the strong antimicrobial capacity specific to lauric acid that predominates in coconut oil.  
It is observed that all cotton samples washed with hot/cold-formulated soaps that have essential oil included in their mass opposed the multiplication of microbes.