This comprehensive review offers a chemical analysis of cutting fluids, delving into both their formulation and deformulation processes. The study covers a wide spectrum of cutting fluid formulations, ranging from simple compositions predominantly comprising oils, whether mineral or vegetable, to emulsions. The latter involves the integration of surfactants, encompassing both nonionic and anionic types, along with a diverse array of additives. Concerning oils, the current trend leans towards the use of vegetable oils instead of mineral oils for environmental reasons. As vegetable oils are more prone to oxidation, chemical alterations, the addition of antioxidant may be necessary. The chemical aspects of the different compounds are scrutinized, in order to understand the role of each component and its impact on the fluid's lubricating, cooling, anti-wear, and anti-corrosion properties. Furthermore, the review explores the deformulation methodologies employed to dissect cutting fluids. This process involves a two-step approach: separating the aqueous and organic phases of the emulsions by physical or chemical treatments, and subsequently conducting a detailed analysis of each to identify the compounds. Several analytical techniques, including spectrometric or chromatographic, can be employed simultaneously to reveal the chemical structures of samples. This review aims to contribute to the improvement of waste treatment stemming from cutting fluids. By gathering extensive information about the formulation, deformulation, and chemistry of the ingredients, there is a potential to enhance the waste management and disposal effectively.

Eleven kinds of Camellia oleifera seed oils (CSOs) were evaluated in terms of chemical constituents, antioxidant activities, acid value (AV) as well as peroxide value (POV). These CSOs contained abundant β-sitosterol, squalene, α-tocopherol and phenolics, in which the squalene was the distinct constituent with the content between 45.8±0.8 and 184.1±5.5 mg/kg. The β-sitosterol ranging from 143.7±4.8 to 1704.6±72.0 mg/kg contributed a considerable content to total accompaniments. Palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid were present in these CSOs, in which the dominant fatty acid was oleic acid with the content between 59.66±0.72 and 82.89±2.16 g/100 g. The AV ranged from 0.1±0.0 to 1.3±0.0 mg KOH/g, and the POV was between 0.1±0.0 and 1.0±0.0 g/100 g. These CSOs showed antioxidant activity based on DPPH and ABTS radical scavenging assay. Both α-tocopherol and β-sitosterol contents showed a positive correlation with DPPH and ABTS values, respectively, while the α-tocopherol content showed a negative correlation with AV. These results suggested that CSO can be categorized into high oleic acid vegetable oil with abundant active constituents, of which the quality presented variation among different origins. These accompaniments may contribute to the delay of its quality deterioration.

Handwashing represents an important personal hygiene measure for preventing infection. Herein, we report the persistence of antibacterial and antiviral effects after handwashing with fatty acid salt-based hand soap. To this end, we developed a new in vitro test method to measure persistence, utilizing coacervation formed by anionic surfactants and cationic polymers to retain highly effective soap components against each bacterium and virus on the skin. Coacervation with fatty acid salts and poly diallyldimethylammonium chloride (PDADMAC) as a cationic polymer allowed the persistence of antibacterial and antiviral effects against E. coli, S. aureus, and influenza virus even 4 h after handwashing. Furthermore, we confirmed an increase in the number of residual components effective against each bacterium and virus on the skin. In summary, the current findings describe an effective approach for enhancing the protective effects of handwashing.

The objective of this research was to evaluate the efficiency of aqueous enzymatic extraction (AEE) to obtain oil from hemp seeds (Cannabis sativa L.) grown in northern Morocco. Optimisation of AEE extraction parameters, including pH, enzyme concentration (hemicellulase, protease and pectinase), temperature and incubation time, to maximize oil yield was achieved using response surface methodology with a central composite design. For comparison, the solvent extraction (Soxhlet) (SE) method was also used. Optimized hydrolysis conditions involved incubation for 4 hours at 60°C with a pH of 6.5, using a multi-enzyme preparation comprising protease, hemicellulase and pectinase at concentrations of 55, 202.5 and 234 U/mg, respectively. Referring to the conventional Soxhlet extraction (SE), Aqueous Enzymatic Extraction (AEE) achieved a 30.65% oil recovery rate under the optimized parameters mentioned above. The use of enzymes produced an oil that was more stable against oxidation than the solvent-extracted oil, with a peroxide value (PV) of 19.54 and 47.87 meq O ₂ /kg, respectively. Furthermore, HPLC-DAD analysis of tocopherol content indicated a higher total tocopherol content (547.2 mg/kg) in Aqueous Enzymatic Extraction (AEE) compared to Soxhlet Extraction (SE) (513.51 mg/kg), with γ-tocopherol being the predominant form. No significant differences in fatty acid composition were observed between the two extraction methods with linoleic acid and alpha-linolenic acid being the predominant constituents.

The objectives were to optimize the reaction conditions for C10:0 incorporation into grapeseed (GS) oil, characterize the structured lipid (SL) product, and study the changes in antioxidant activity of the SL. Taguchi method was used to optimize C10:0 incorporation by combining parameters in a total of 9 experiments. Lipozyme ^® RM IM (Rhizomucor miehei immobilized lipase) and Lipozyme ^® 435 (Candida antarctica recombinant immobilized lipase) were used as biocatalysts for the acidolysis reactions. C10:0 incorporation and triacylglycerol (TAG) species of the SL were analyzed to determine optimal conditions and enzyme type that gave higher incorporation. The optimal conditions were the same for both enzymes as follows: substrate molar ratio 1:3 (GS oil: C10:0), enzyme load 5% (w/w) of substrates, temperature 65℃, and time 12 h. HPLC analysis of SL gave MLM-type TAG species of 11.51±0.11 mol% and 12.68±0.34 mol% for Lipozyme ^® RM IM and Lipozyme ^® 435, respectively. GC analysis indicated that C10:0 incorporated at the sn-1,3 positions of the SL were 46.03±0.55 mol% and 47.28±1.22 mol%, respectively, for Lipozyme ^® RM IM and Lipozyme ^® 435. However, the total C10:0 incorporated into TAG species with Lipozyme ^® RM IM was significantly higher (60.08±0.04 mol%) compared to 50.78±0.44 mol% for Lipozyme ^® 435. Scaled-up (300 g) acidolysis reaction and characterization were done on SL synthesized using Lipozyme ^® RM IM. SL reaction product was purified using short path distillation and fully characterized in terms of lipid classes, tocopherol, thermal behavior, and oxidative stability. The yield of purified scaled-up SL after short path distillation (SPD) was 72.96 wt%. The antioxidant in SL was reduced after SPD due to loss of tocopherols. This MLM-type-SL synthesized within 12 h using Lipozyme ^® RM IM had a high content of C10:0 and may have functional and health benefits.

In this study, we evaluated the cancer cell killing activity of koji mold-derived extracts using several solvents. The koji mold lipid extract (KML) exhibited potent cytotoxicity against a human leukemia cell line. Fractionation of the KML via silica gel chromatography revealed the presence of active components in fraction (Fr.) 6. Cytotoxic effects of Fr. 6 were inhibited by the ferroptosis inhibitors, ferrostatin-1 and SRS11-92, and the iron chelator, deferoxamine. Interestingly, ferroptosis inhibitors failed to prevent the KML-induced cell death. Fr. 6 decreased the expression of glutathione peroxidase 4 (GPx4) and increased the level of peroxidized plasma membrane lipids. Furthermore, Fr. 6 decreased the intracellular glutathione levels. Overall, our results suggest that Fr. 6 included in KML induces ferroptosis in HL-60 cells.

The negative impact of lipid peroxidation on health is intimately tied to its oxidation products. In this study, methyl oleate was oxidized at 180℃ for 0, 2, 4, 8 and 12 h respectively. The free radicals and volatile components generated during the oxidation process were determined using electron spin resonance and headspace solid-phase microextraction (HS-SPME)-GC-MS. The pro-inflammatory effects of oxidized methyl oleate were evaluated in RAW264.7 cells. Then partial least-squares regression (PLSR) models were established for predicting the 3 pro-inflammatory genes expression based on the volatile components. The results revealed that the alkoxy radical content increased rapidly during oxidation from 4 h to 8 h, and the rate of oxidation of methyl oleate dropped after 8 h. A total of 27 volatile oxidation compounds were detected by HS-SPME-GC-MS. The content of most compounds, including aldehydes, esters, and acids, exhibited a pattern of initial increase and then decrease as the oxidation time increased. Similarly, the proinflammatory effects of oxidized methyl oleate peaked after 8 h of oxidation. The PLSR quantitative prediction models showed that the coefficient of determination (R²_P) between the predicted and measured values of the 3 inflammatory gene expressions were 0.915, 0.946 and 0.951 respectively. The established PLSR model predicts the pro-inflammatory effects of oxidized methyl oleate well and provides a theoretical foundation for quick evaluation of the pro-inflammatory effects of oxidized lipids.

Herein, we evaluated friction dynamics of human skin treated with polyacrylic acid aqueous solutions or gel creams using a sinusoidal motion friction evaluation system to demonstrate the effect of treatment with polymer aqueous solutions on human skin. A polymer aqueous solution or gel cream was applied to the inner forearms of 10 subjects to evaluate temporal changes in friction force under sinusoidal motion. Water content, skin viscoelasticity, and transepidermal water loss were also simultaneously measured to determine the effects on skin conditions. When human skin was treated with the polymer aqueous solution, the friction coefficient immediately after treatment was 0.69–0.99 and the delay time δ, a normalized parameter of the time difference in the delayed response of friction to the movement of the contact probe divided by the friction time T ₀ for one round trip, was 0.171–0.179, which was greater than that of untreated skin. This increase was caused by the swelling and softening of the stratum corneum caused by the penetration of water in the polymer aqueous solution, which increased true contact area between the skin and contact probe. A significant difference was observed in the friction coefficient of the skin immediately after treatment with different polymer aqueous solutions. Among polymers (P1–P4), P4, which has a low-salt resistance and low yield stress, had the lowest friction coefficient because of collapsing of the polymer network structures by shearing and reduced viscosity owing to salts on human skin. The skin treated with a gel cream also exhibited a greater friction coefficient than the untreated skin immediately after treatment and 90 min later. This phenomenon can be caused by the occlusive effect of the oil in the gel cream.

This paper reports a novel α-gel formulation technology referred to as polymer complexed lamella (PCL) that uses hydroxypropyl methyl cellulose (HPMC) and glycerol. The PCL method suppressed lipid crystallization even after drying. This effect was maximized by the addition of HPMC and glycerol at high temperature. HPMC and lipids coexisted when mixed at high temperature, which decreased the mobility of HPMC, an effect that was enhanced by the strong interaction of glycerol with HPMC. These results indicate that mixing of HPMC with glycerol directly regulates the lipid structure and suppresses crystallization. PCL also maintained the effect of occlusion related to the moisturization of skin, even if the membrane was repeatedly bent such as in facial expressions.