Health Benefits of Acerola Cherry

Malpighia fruits (Malpighiae emarginata DC/ Malpighia glabra L.), commonly known as acerola cherry come from a plant originating in Yucantan. It then spread among the Americas till Brazil, and then around the equator. The plant presents interesting and valuable health-promoting properties. Consumers are starting to recognize acerola primarily as a fruit high in vitamin C, or ascorbic acid ^[1]. In addition to having an extremely high ascorbic acid concentration, it also contains a plethora of other phytonutrients like phenolics, flavonoids, anthocyanins and carotenoids in a fair amount. Pro-vitamin A, vitamins B1 and B2, niacin, albumin, iron, phosphorus, and calcium are also present in the fruit. Acerola is appropriately referred to as a “super fruit” ^[2].

The study’s findings support the idea that acerola is primarily a valuable source of ascorbic acid. For this reason, consumption of acerola can strongly stimulate the immune system, including by increasing the number and activity of immune cells, such as lymphocytes ^[1]. Acerola pulp and juices have a higher phenolic content than fruits such as caqui, pineapple, mango, guayaba, etc., but a lower anthocyanin level than other anthocyanin-rich fruit juices like blood orange or strawberries ^[2]. Acerola fruit was shown to have a high β-carotene content of 5.84 mg/g dry weight through biochemical analysis, which suggests that this raw material may be just as valuable as conventional carrots as a source of β-carotene ^[1].

The Benefits of Acerola Cherry

Antioxidant and Anti-Inflammatory Effects

The hypothesizes that the antioxidant activity of acerola by-product extracts depends on several factors, such as the presence of phenolic compounds, ascorbic acid content, and other species of radical scavengers, as well as the possible synergistic effect of different constituents ^[3]. According to research on animals, rats fed a high-fat diet supplemented with acerola fruit pulp had less M1 macrophages in their liver and colon. When M1 macrophages interact with Toll-like receptor 4, they release pro-inflammatory cytokines such IL-1β and TNF-α, which induce mild to severe tissue inflammation ^[1].

Carotenoids, including β-carotene, constitute the other class of bioactive chemicals found in acerola that have anti-inflammatory characteristics. It has also been established that lutein, β-cryptoxanthin, and α-carotene are among the carotenoids found in acerola ^[1]. The anti-inflammatory properties of acerola may also depend on the large amounts of ascorbic acid it contains, which exhibits strong antioxidant activity. According to a study by Righetto, the synergistic interaction of the constituents of various fractions—primarily ascorbic acid and polyphenolic compounds—has a major impact on the antioxidant activity of acerola juices ^[1].

In another study on the effects of acerola, it was shown that consuming acerola raw material can significantly lower the level of the pro-inflammatory cytokine TNF-α, or tumor necrosis factor, in the liver when there are damaging (toxic) effects of other substances on the liver, such as carbon tetrachloride. In an experiment, the protective effect of acerola was demonstrated when rats were subjected to the toxic effects of carbon tetrachloride (CCl₄). When animals exposed to the toxic effects of carbon tetrachloride were given acerola leaf extract, the amount of TNF-α in the liver was found to be significantly (up to 42%) lower than in animals treated with CCl₄ but not given acerola leaf extract ^[1].

According to studies, the polyphenolic compounds found in acerola fruit can help restore the bacterial flora in the intestines and prevent pathogen growth and action, therefore reducing inflammatory processes in the intestines. As a result, fewer endotoxins produced by pathogenic microorganisms are produced. The polyphenolic compounds derived from acerola also have the additional property and anti-inflammatory effect of inhibiting activated M1 macrophages and pro-inflammatory mediator production, such as interleukin, IL-6 ^[1].

Promotes Ascorbic Acid Uptake into Human Intestinal Cells

Ascorbic acid is one of the most important water-soluble vitamins, essential for collagen, carnitine and neurotransmitters biosynthesis. Ascorbic acid can be synthesized by most animals and plants, but not by humans. As a result, it is a necessary supplement for people to consume. Acerola is a naturally occurring food that contains 1000 – 4500 mg/100 g of vitamin C, or about 50 – 100 times more than orange or lemon juice. According to reports, humans are able to absorb vitamin C from acerola better than from the synthetic ascorbic acid. In healthy Japanese participants, Uchida et al. compared the absorption and excretion of acerola juice and ascorbic acid alone. Their results indicated that some component of acerola juice favorably affected the absorption and excretion of ascorbic acid. The absorption of vitamin C is highly efficient up to a daily consumption of 100 mg. At higher intake levels (500 mg), the rate of ascorbic acid absorption rapidly decreases ^[2].

A human intestinal model is used in a study to compare the ascorbic acid uptake from the apical side into human intestinal epithelial cell line (Caco-2 cells) between ascorbic acid alone and ascorbic acid in acerola juice at the same dose. The findings demonstrated that intracellular ascorbic acid contents gradually increased until 24 hours following incubation with ascorbic acid in acerola juice and ascorbic acid alone. However, these contents incubated with ascorbic acid in acerola juice were significantly higher compared to those incubated with ascorbic acid alone at 2, 3, 4, 8, and 24 h, respectively ^[4].

Two special transporters, sodium dependent vitamin C transporters 1 and 2 (SVCT1 and SVCT2), are known to be involved in the migration of ascorbic acid across cell membranes. SVCT1 and SVCT2 play pivotal roles in the sodium-dependent and secondary active transport of ascorbic acid from the outer to the interior of cells. The study demonstrated that ascorbic acid in acerola juice was shown to increase SVCT1 mRNA expression levels by 1.8 times when compared to ascorbic acid alone; nevertheless, there were no variations seen in the amounts of SVCT2 mRNA expression between ascorbic acid and ascorbic acid in acerola juice. These results strongly suggested the possibility that acerola enhanced the SVCT1 gene expression in the Caco-2 cells and contributed to a high Ascorbic acid uptake ^[4].

Skin-Lightening Effect

Melanin plays an important role in preventing ultraviolet (UV) light-induced skin damage. On the other hand, a pathological rise in melanin formation may result from excessive UV light exposure. The mechanism by which UV irradiation causes skin melanogenesis has been considerably extended by recent work. Tyrosinase gene upregulation is caused by UV photons’ direct influence on DNA, and this ultimately causes epidermal hyperpigmentation. The first two rate-limiting steps in the melanin synthesis pathway are the conversion of
L-tyrosine to 3,4-dihydroxyphenylalanine (DOPA) and DOPA to DOPA quinone, which are both oxidized by tyrosinase. UV radiation also induces the formation of reactive oxygen species (ROS) in the skin; these ROS contribute to melanin biosynthesis and DNA damage and may then induce the proliferation and/or apoptosis of melanocytes. Therefore, melanogenesis in the skin’s epidermal layer may be inhibited by tyrosinase inhibitors or other ROS scavengers like antioxidants ^[5].

The skin pigmentation of guinea pigs was significantly reduced by day 14 when crude polyphenol concentrated extract from acerola (C-AP) was administered orally after UVB irradiation. Data from the current study, which used melanoma cells, indicate that the inhibition of melanin formation in the melanocytes may have been the cause of C-AP’s skin-lightening impact. While a number of factors have been attributed to melanin biosynthesis in melanocytes, the main mechanism for skin tanning caused by UVB is considered to be melanin production through the increased activity of tyrosinase. Therefore, investigated whether or not the skin-lightening effect of C-AP resulted from the inhibition of tyrosinase activity and found that C-AP did effectively inhibit the tyrosinase activity ^[5].

A study has examined the impact of consuming acerola juice on the skin of hairless mice that have senescence marker protein 30 (SMP30)/gluconolactonase (GNL) knockout (KO) mutations. This study found that consuming acerola juice at the same dosage as ascorbic acid reduces the excessive UVB-induced skin pigmentation. The suppressive effect of acerola juice intake on skin pigmentation may have been due to the inhibitory effects of polyphenols on melanogenesis. Furthermore, UVB exposure facilitates the release of pro-inflammatory mediators, including TNF-α and endothelin 1 (Edn1), from keratinocytes. TNF-α promotes immune cell infiltration into the skin, which causes the infiltrated immune cells to release elastases and collagenases and destroy the skin. It seems that acerola juice can reduce UVB-induced inflammation because there was no difference in TNF-α mRNA expression between the acerola juice and ascorbic acid (+) groups. Edn1 is regarded as one of the most effective agonists for inducing melanocytes to accelerate melanogenesis. Because the Edn1 mRNA level in the acerola juice group was lower than that in the ascorbic acid (+) group, acerola juice intake may suppress melanogenesis-related cytokines ^[6].

Lipolysis Effect

The current study demonstrated that the intake of acerola juice improved lipolysis and reduced the amount of TNF-α in mice fed a cafeteria diet. Several studies have shown that high-fat diet-induced adiposity can be reduced by vitamin C in rats and by modifications to adipocyte catecholamine-induced lipolysis. Furthermore, vitamin C has been shown by Garcia-Diaz et al. to regulate an inflammatory state that has already been created in the interaction between macrophages and adipocytes. Additionally, the production of catecholamines by local macrophages promotes lipolysis in white adipose tissue. This pathway may be implicated in the central mechanisms of the increased lipolysis and anti-inflammatory effects of acerola juice, because IL-4, an anti-inflammatory cytokine, is necessary for the activation of lipolysis. The associated increase in catecholamine production in macrophages may explain the increased level of IκB-α proteins and reduction in TNF-α protein levels. However, there are additional biocompounds in acerola juice that might be connected to the effects on inflammation and metabolism that have been noted ^[7].

Acerola juice suppresses glucose absorption and blood glucose elevation after feeding. This decrease in glucose disposition by the energetic metabolism can be responsible, due to the increased fatty acid utilization, for maintaining the energetic demand, ameliorating the vicious cycle of lipolysis-inflammation, and mobilizing the free fatty acids from lipolysis to be used as an energy source. However, recently, Leffa et al. demonstrated that acerola juice cannot change or reverse insulin resistance in mice given a diet heavy in fat. To fully comprehend the related mechanisms, more research is required ^[7].

 

References

1. Olędzki R, Harasym J. Acerola (Malpighia emarginata) Anti-Inflammatory Activity-A Review. International Journal of Molecular Sciences. 2024 [cited 2024 April 18]; 25: 1-17. Available form: https://www.mdpi.com/1422-0067/25/4/2089
2. Prakash A, Baskaran R. Acerola, an untapped functional superfruit: a review on latest frontiers. Journal of Food Science and Technology. 2018 [cited 2024 April 24]; 55: 3373-84. Available form: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6098779/
3. Mesquita P, Rodrigues L, Mazzutti S, Ribeiro P, de Brito E, Lanza M. Untargeted metabolomic profile of recovered bioactive compounds by subcritical water extraction of acerola (Malpighia emarginata DC.) pomace. Food Chemistry. 2022 [cited 2024 April 24]; 397: 1-10. Available form: https://www.sciencedirect.com/science/article/pii/S0308814622016806?via%3Dihub
4. Takino Y, Aoki H, Kondo Y, Ishigami A. Acerola (Malpighia emarginata DC.) Promotes Ascorbic Acid Uptake into Human Intestinal Caco-2 Cells via Enhancing the Gene Expression of Sodium-Dependent Vitamin C Transporter 1. Journal of Nutritional Science and Vitaminology (Tokyo). 2020 [cited 2024 April 24]; 66: 296-9. Available form: https://www.jstage.jst.go.jp/article/jnsv/66/4/66_296/_article
5. Hanamura T, Uchida E, Aoki H. Skin-lightening effect of a polyphenol extract from Acerola (Malpighia emarginata DC.) fruit on UV-induced pigmentation. Biosci Biotechnol Biochem. 2008 [cited 2024 April 24]; 72: 3211-8. Available form: https://academic.oup.com/bbb/article/72/12/3211/5941013
6. Sato Y, Uchida E, Aoki H, Hanamura T, Nagamine K, Kato H, et al. Acerola (Malpighia emarginata DC.) Juice Intake Suppresses UVB-Induced Skin Pigmentation in SMP30/GNL Knockout Hairless Mice. Plos One. 2017 [cited 2024 April 24]; 12: 1-15. Available form: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0170438
7. Dias F, Leffa D, Daumann F, Marques Sde O, Luciano T, Possato J, et al. Acerola (Malpighia emarginata DC.) juice intake protects against alterations to proteins involved in inflammatory and lipolysis pathways in the adipose tissue of obese mice fed a cafeteria diet. Lipids in Health and Disease. 2014 [cited 2024 April 24]; 13: 1-9. Available form: https://lipidworld.biomedcentral.com/articles/10.1186/1476-511X-13-24