The monoterpenol group exhibits anti-inflammatory properties, while the ester group enhances the synthesis of elastin and possesses anti-wrinkle features. Given that similar structures tend to display comparable bioactivities, we have classified the GC-MS results into analogs. This method facilitates the organization of the complex components [37–40]. TGLON is primarily composed of monoterpenols, supported by sesquiterpenes, other oxides, monoterpenes, sesquiterpenols, and ketones, with a proportion of low-irritancy aldehydes enhancing the blend. This formulation meets our anticipated specifications.
In TGLON, Terpinen-4-ol, Camphor, and δ-Cadinene are crucial components recognized for their ability to inhibit cancer cells [29–31]. However, when Terpinen-4-ol dominates the composition of essential oils, it results in 50% cytotoxicity to MRC-5 normal cells at a dilution of 14,000 times [25]. Similarly, Camphor as the primary component inflicts 50% damage to MRC-5 normal cells at a dilution of 238,000 times [41]. Extracts where δ-Cadinene is the principal component also cause 50% damage to MRC-5 normal cells at a dilution of 3,900 times [42]. Despite this, TGLON demonstrates a high survival rate of 95.4% in MRC-5 cells at an 80-fold dilution, underscoring its safety and marking a significant advancement for hydrosol blends. The enhanced safety profile of TGLON for MRC-5 cells may stem from Terpinen-4-ol ability to inhibit the production of lipopolysaccharide (LPS)-induced tumor necrosis factor-α (TNF-α), interleukins IL-1β, IL-6, IL-10, and prostaglandin E2 (PG-E2) [38, 43]. Additionally, Camphor effectively reduces the expression of IL-1β, IL-6, and TNF-α [44], while δ-Cadinene curbs the production of LPS-induced nitric oxide (NO) [45].
TGLON demonstrates bioactivity in inhibiting A-549 lung cancer cells, likely due to components such as terpinen-4-ol, camphor, δ-Cadinene, 1,8-Cineole, γ-Terpinene, and particularly cedrol. Cedrol is noted for its ability to induce apoptosis in A-549 cells by reducing mitochondrial transmembrane potential (MTP) and downregulating phosphatidylinositol 3'-kinase (PI3K)/Akt expression [46–48]. Additionally, TGLON may inhibit HepG2 liver cancer cells, likely due to the presence of terpinen-4-ol, γ-Terpinene, and α-pinene [49, 50]. It is also capable of suppressing MCF-7 breast cancer cells through the actions of Terpinen-4-ol, α-Terpineol, Camphor, and Safrole [30, 51–53]. Furthermore, camphor, 1,8-cineole, and α-pinene contribute to its potential to inhibit MKN-45 stomach cancer cells [54].
TGLON may also inhibit MOLT-4 leukemic lymphoblasts, potentially through Terpinen-4-ol, which impacts cell survival by causing loss of mitochondrial membrane potential and releasing cytochrome c into the cytosol. This triggers caspase-8 activation, leading to the cleavage of cytosolic Bid, which activates mitochondria in a process linked to the downregulation of Bcl-2 protein and upregulation of caspase-3 [55].
In an acute toxicity assay, the oral lethal dose (LD50) of Terpinen-4-ol administered to rats was determined to be 1.3 g/mL [56]. The LD50 for camphor, similarly administered orally, was recorded at 1.31 g/mL [57]. Nonetheless, no mortality or symptoms of toxicity were observed in rats following the administration of a 50% (v/v) TGLON solution at a dosage of 10 mL/kg (effective dose 5 mL/kg), and their body weights continued to grow normally. This indicates that TGLON is safer than monomeric compounds [58, 59]. The effectiveness of TGLON in alleviating IPF is consistent with that of U.S. FDA-approved drugs Nintedanib and Pirfenidone used for IPF treatment. The mechanism by which TGLON ameliorates IPF may involve active components from the monoterpenol group, such as α-Terpineol, (-)-Myrtenol, Borneol, cis-Myrtanol, and Terpinen-4-ol, as well as β-Citronellal from the aldehyde group. These constituents are believed to reduce the expression of Malondialdehyde (MDA), Alpha-Smooth Muscle Actin (α-SMA), Transforming Growth Factor-Beta (TGF-β), Cyclooxygenase-2 (COX-2), Prostaglandin E2 (PGE2), and Tumor Necrosis Factor-Alpha (TNF-α), while enhancing the expression of superoxide dismutase (SOD) [8].