Compendium of the most significant studies with reference to properties, intake, effects.

Hanana M, Mezghenni H, Ben Ayed R, Ben Dhiab A, Jarradi S, Jamoussi B, Hamrouni L. Nutraceutical potentialities of Tunisian Argan oil based on its physicochemical properties and fatty acid content as assessed through Bayesian network analyses. Lipids Health Dis. 2018 Jun 15;17(1):138. doi: 10.1186/s12944-018-0782-9. 

Abstract. Background: Argan oil is traditionally produced by cold pressing in South-western Morocco where rural population uses it as edible oil as well as for its therapeutic properties which give them in counterpart valuable income. Given the economical interest of this oil, several attempts of fraudulency have been registered in the world global market leading to loss of authenticity. Our purpose is to launch a program of Tunisian Argan oil valorization since trees from this species have been introduced sixty years ago in Tunisia. The first step was thus to characterize the physicochemical properties and determine the chemical composition of Tunisian Argan oil in order to assess its quality. Methods: Physicochemical parameters of oil quality were determined according to the international standard protocols. Fatty acid content analysis of Argan oils was performed by gas chromatography coupled to mass spectrophotometry. A comparative study was realized among Tunisian, Moroccan and Algerian samples differing also by their extraction procedure. The impact of geographical localisation on the fatty acids composition was studied by statistical and modeling Bayesian analyses. Results: Physicochemical parameters analysis showed interestingly that Tunisian Argan oil could be classified as extra virgin oil. Argan oil is mainly composed by unsaturated fatty acids (80%), mainly oleic and linoleic acid (linoleic acid was positively influenced by the geographical localization (r = 0.899, p = 0.038) and the P/S index (r = 0.987, p = 0.002)) followed by saturated fatty acids (20%) with other beneficial compounds from the unsaponifiable fraction like polyphenols and carotenoids. Together with fatty acid content, these minor components are likely to be responsible for its nutraceutical properties and beneficial effects. Conclusion: Tunisian Argan oil displayed valuable qualitative parameters proving its competitiveness in comparison with Moroccan and Algerian oils, and could be therefore considered as extra virgin edible oil for nutraceutical purposes as well as for cosmetic use.

Malinowska P, Gliszczyńska-Świgło A, Szymusiak H. Commercial plant extracts may act as antioxidants or pro-oxidants in cosmetic emulsions based on argan oil. J Cosmet Sci. 2017 Mar/Apr;68(2):147-158. 

Abstract. Cosmetic emulsions containing plant extracts should be tested in a range of temperatures from 5°C to 40°C to be sure that they will be stable during general use by consumers and that plant extracts used as antioxidants do not accelerate oxidative degradation of their oil base. The oxidative stability of argan oil-in-water emulsions containing 1% and 5% commercial acerola, willow, and rose extracts [or 0.01% butylhydroxytoluene (BHT)], stored at 5°C and 20°C for 6 months and at 40°C for 4 weeks, was monitored by the determination of peroxide content. The antioxidant or pro-oxidant activities of extracts or BHT in emulsions were expressed as the protection factor (PF) and inhibition of peroxide formation (Ip). At the end of storage, 5% willow, 0.01% BHT, 1% willow, and 5% acerola were the most protective for emulsions stored at 5°C. At 20°C, the most effective was 0.01% BHT, 5% rose, and 5% acerola. At 40°C, inhibition of peroxide formation calculated for 1% rose, 5% acerola, and 0.01 % BHT was similar. Altogether, the results show that some plant extracts, depending on storage conditions, may act as pro-oxidants, whereas the others can be applied as natural antioxidants instead of synthetic BHT.

El Midaoui A, Haddad Y, Filali-Zegzouti Y, Couture R. Argan Oil as an Effective Nutri-Therapeutic Agent in Metabolic Syndrome: A Preclinical Study. Int J Mol Sci. 2017 Nov 22;18(11):2492. doi: 10.3390/ijms18112492.

Abstract. The present study aims at examining the effects of argan oil on the three main cardiovascular risk factors associated with metabolic syndrome (hypertension, insulin resistance and obesity) and on one of its main complications, neuropathic pain. Male Sprague-Dawley rats had free access to a drinking solution containing 10% d-glucose or tap water for 12 weeks. The effect of argan oil was compared to that of corn oil given daily by gavage during 12 weeks in glucose-fed rats. Glucose-fed rats showed increases in systolic blood pressure, epididymal fat, plasma levels of triglycerides, leptin, glucose and insulin, insulin resistance, tactile and cold allodynia in association with a rise in superoxide anion production and NADPH oxidase activity in the thoracic aorta, epididymal fat and gastrocnemius muscle. Glucose-fed rats also showed rises in B₁ receptor protein expression in aorta and gastrocnemius muscle. Argan oil prevented or significantly reduced all those anomalies with an induction in plasma adiponectin levels. In contrast, the same treatment with corn oil had a positive impact only on triglycerides, leptin, adiponectin and insulin resistance. These data are the first to suggest that argan oil is an effective nutri-therapeutic agent to prevent the cardiovascular risk factors and complications associated with metabolic syndrome.

Lizard G, Filali-Zegzouti Y, Midaoui AE. Benefits of Argan Oil on Human Health-May 4-6 2017, Errachidia, Morocco. Int J Mol Sci. 2017 Jun 28;18(7):1383. doi: 10.3390/ijms18071383.

Abstract. Objective: The present study was designed to examine the effects of argan oil on two cardiovascular risk factors notably arterial hypertension and insulin resistance as well as on the aortic basal superoxide anion production and NADPH oxidase activity in one nutritional model of hypertensive and insulinoresistant rat. Methods: Sprague-Dawley rats had free access to a drinking solution containing 10% D-glucose or tap water (control) for 5 weeks. The impact of argan oil was compared to that of corn oil given daily by gavage (5 mL/kg) during 5 weeks in glucose-fed rats. Oxidative stress was evaluated by measuring the superoxide anion production and the NADPH oxidase activity using the lucigenin method. Results: Five weeks treatment with glucose led to increases in systolic blood pressure, plasma glucose and insulin levels and insulin resistance index in association with a rise in superoxide anion production and NADPH oxidase activity (sensitive to diphenyleneiodonium) in the aorta. The simultaneous treatment with argan oil prevented or significantly reduced all those effects, yet the same treatment with corn oil had a positive impact only on hyperinsulinemia and insulin resistance. Conclusions: These findings demonstrate that argan oil treatment reduced the elevation in blood pressure, hyperglycemia and insulin resistance through its anti-oxidative properties in glucose-fed rats. Hence argan oil which is now available in the market as consumable food may be of potential therapeutic value in the treatment of arterial hypertension and insulin resistance.

Lamaoui M, Chakhchar A, Benlaouane R, El Kharrassi Y, Farissi M, Wahbi S, El Modafar C. Uprising the antioxidant power of Argania spinosa L. callus through abiotic elicitation. C R Biol. 2019 Jan-Feb;342(1-2):7-17. doi: 10.1016/j.crvi.2018.11.001. 

Abstract. This study was carried out in order to investigate the ability of tissues of Argania spinosa (L.) to undergo unlimited cell divisions by triggering their proliferative potential via callogenesis. Axenic cultures were efficiently established using axillary buds cultured on half-strength Murashige and Skoog (MS) medium after 20min of surface sterilization with sodium hypochlorite 6% (v/v). The highest callus rate was achieved with 1.0mgL-1 of naphthaleneacetic acid (NAA) and 1.0mgL-1 of 2,4-dichlorophenoxyacetic acid (2,4D) or similarly with 0.01mgL-1 of 6-benzylaminopurine (BAP) and 1.0mgL-1 of 2,4D at pH of 5.8, under dark conditions. The results of this study show also a significant increase in the callus's antioxidant power under abiotic pressure induced by NaCl. Catalase (CAT), peroxidase (PO), and superoxide dismutase (SOD) activities were significantly triggered, which protected the cells from the stimulated oxidative stress, under hydrogen peroxide (H2O2) significant release. This reaction favors subsequently the tissue recover process linked to the low abundance of polyphenol oxidase (PPO) activity and malondialdehyde (MDA) content. This work proves the efficiency of salt stress in boosting the argan cell's antioxidant status, which could be commercially applied in the field of cells regenerative therapy. Copyright © 2018 Académie des sciences. 

Haimeur A, Meskini N, Mimouni V, Ulmann L, Messaouri H, Pineau-Vincent F, Abouakil N, Tremblin G. A comparative study on the effect of argan oil versus fish oil on risk factors for cardio-vascular disease in high-fat-fed rats. Nutrition. 2019 Jan;57:32-39. doi: 10.1016/j.nut.2018.05.027. 

Abstract. Objectives: The aim of this study was to investigate the effects of two different sources of polyunsaturated fatty acid-fish oil (FO) and argan oil (AO)-on some risk factors for cardiovascular disease, such as platelet aggregation, dyslipidemia, and oxidative stress....Conclusions: For rats, the consumption of FO prevented the development of adiposity, restored insulin sensitivity, decreased plasma and liver lipid levels, and also prevented the prothrombotic effect. Intake of AO as a food supplement did not affect adiposity or liver lipid levels but decreased plasma lipid levels and improved oxidative status and platelet activity. FO and, to a lesser degree, AO thus represent promising nutritional tools in the prevention of cardiovascular disease. Copyright © 2019. 

Bakour M, Soulo N, Hammas N, Fatemi HE, Aboulghazi A, Taroq A, Abdellaoui A, Al-Waili N, Lyoussi B. The Antioxidant Content and Protective Effect of Argan Oil and Syzygium aromaticum Essential Oil in Hydrogen Peroxide-Induced Biochemical and Histological Changes. Int J Mol Sci. 2018 Feb 18;19(2):610. doi: 10.3390/ijms19020610.

Abstract. Oxidative stress is an important etiology of chronic diseases and many studies have shown that natural products might alleviate oxidative stress-induced pathogenesis. The study aims to evaluate the effect of Argan oil and Syzygium aromaticum essential oil on hydrogen peroxide (H₂O₂)-induced liver, brain and kidney tissue toxicity as well as biochemical changes in wistar rats. The antioxidant content of Argan oil and Syzygium aromaticum essential oil was studied with the use of gas chromatography. The animals received daily by gavage, for 21 days, either distilled water, Syzygium aromaticum essential oil, Argan oil, H₂O₂ alone, H₂O₂ and Syzygium aromaticum essential oil, or H₂O₂ and Argan oil. Blood samples were withdrawn on day 21 for the biochemical blood tests, and the kidney, liver and brain tissue samples were prepared for histopathology examination. The results showed that the content of antioxidant compounds in Syzygium aromaticum essential oil is higher than that found in Argan oil. H₂O₂ increased level of blood urea, liver enzymes, total cholesterol, Low Density Lipoprotein (LDL-C), Triglycerides (TG) and Very Low Density Lipoprotein (VLDL), and decreased the total protein, albumin and High Density Lipoprotein-cholesterol (HDL-C). There was no significant effect on blood electrolyte or serum creatinine. The histopathology examination demonstrated that H₂O₂ induces dilatation in the central vein, inflammation and binucleation in the liver, congestion and hemorrhage in the brain, and congestion in the kidney. The H₂O₂-induced histopathological and biochemical changes have been significantly alleviated by Syzygium aromaticum essential oil or Argan oil. It is concluded that the Argan oil and especially the mixture of Argan oil with Syzygium aromaticum essential oil can reduce the oxidative damage caused by H₂O2, and this will pave the way to investigate the protective effects of these natural substances in the diseases attributed to the high oxidative stress.