Orange (Citrus sinensis) Research

Latin Name: Citrus sinensis / Citrus aurantium

Family: Apiaceae

RESEARCH

The listings of research below represent a compilation of scientific articles found on the species, with a very brief overview description of each article/study.  Research found is catalogued by therapeutic action.  This categorized compilation of research articles does not necessarily imply that there are adequate results to demonstrate safe and/or effective human use.

GENERAL

• Lis-Balchin, M. (2006). Aromatherapy Science: A guide for healthcare professionals. London: Pharmaceutical Press.
• Sohi, S., & Shri, R. (2018). Neuropharmacological potential of the genus Citrus: A review. J. Pharmacogn. Phytochem, 7(2), 1538-1548.
• Scientific research on the therapeutic actions of Citrus ssp were reviewed.  Sweet and bitter orange showed anti-acne, sedative, anxiolytic, hepatoprotective, anti-tumor, anti-cancer, food preserving, antibacterail, antifungal, larvicidal, insecticidal, anthelmintic, analgesic, anti-seizure, anti-spasmodic, gastroprotective, and aphrodisiac activities.  From:  Dosoky, N., & Setzer, W. (2018). Biological activities and safety of Citrus spp. essential oils. International journal of molecular sciences, 19(7), 1966.
• Osman, A. (2019). Citrus Oils. In Fruit Oils: Chemistry and Functionality (pp. 521-540). Springer, Cham.
• A review of research on the bioactivity of citrus peels was provided and included antioxidant, anti-diabetic, cardioprotective, neuroprotective and anticancer possibilities. From: Ademosun, A. O., Oboh, G., Olasehinde, T. A., & Adeoyo, O. O. (2018). From folk medicine to functional food: a review on the bioactive components and pharmacological properties of citrus peels. Oriental Pharmacy and Experimental Medicine, 18(1), 9-20.
• Lemon, as well as lime and bitter orange oil contained furocoumarin (bergapten and oxypeucedanin) causing phototoxicity.  From:  Naganuma, M., Hirose, S., Nakayama, Y., Nakajima, K., & Someya, T. (1985). A study of the phototoxicity of lemon oil. Archives of dermatological research, 278(1), 31-36.
• Furocoumarins have shown in research to have significant antimicrobial, insecticidal, and cancer inhibiting activity. However, there is also a phototoxic effect and there can be interference with drug metabolism. Furocoumarins are found in grapefruit, lemon, lime, orange, carrot, celery, parsnip, dill, parsley, cilantro, cumin, coriander, turnip, and fig. From: Melough, M. M., Cho, E., & Chun, O. K. (2018). Furocoumarins: a review of biochemical activities, dietary sources and intake, and potential health risks. Food and Chemical Toxicology, 113, 99-107.

SAFETY

• Lemon, as well as lime and bitter orange pressed oil contains furocoumarin (bergapten and oxypeucedanin) causing phototoxicity.  From:  Naganuma, M., Hirose, S., Nakayama, Y., Nakajima, K., & Someya, T. (1985). A study of the phototoxicity of lemon oil. Archives of dermatological research, 278(1), 31-36.
• Lemon, as well as lime and bitter orange oil contained furocoumarin (bergapten and oxypeucedanin) causing phototoxicity.  From:  Naganuma, M., Hirose, S., Nakayama, Y., Nakajima, K., & Someya, T. (1985). A study of the phototoxicity of lemon oil. Archives of dermatological research, 278(1), 31-36.
• The high limonene content of the cold pressed oil can cause contact dermatitis, especially with oxidized oils.
• Furocoumarins have shown in research to have significant antimicrobial, insecticidal, and cancer inhibiting activity. However, there is also a phototoxic effect and there can be interference with drug metabolism. Furocoumarins are found in grapefruit, lemon, lime, orange, carrot, celery, parsnip, dill, parsley, cilantro, cumin, coriander, turnip, and fig. From: Melough, M. M., Cho, E., & Chun, O. K. (2018). Furocoumarins: a review of biochemical activities, dietary sources and intake, and potential health risks. Food and Chemical Toxicology, 113, 99-107.

ANTIMICROBIAL / ANTIFUNGAL / ANTIBACTERIAL / ANTIVIRAL

• Citrus sinensis peel extracts were active against multiple tested human pathogenic bacteria.  From:  Mehmood, B., Dar, K. K., Ali, S., Awan, U. A., Nayyer, A. Q., Ghous, T., & Andleeb, S. (2015). In vitro assessment of antioxidant, antibacterial and phytochemical analysis of peel of Citrus sinensis. Pakistan journal of pharmaceutical sciences, 28(1).
• Citrus sinensis (Orange), Citrus limon (lemon) and Citrus bergamia (bergamot) were studied as a biological control alternative to chemical fungicides against Algerian strains of Phytophthora infestans, responsible for potato late blight.  All three essential oils demonstrated fungicidal effects with bergamot performing the best.  From:  Messgo-Moumene, S., Li, Y., Bachir, K., Houmani, Z., Bouznad, Z., & Chemat, F. (2015). Antifungal power of citrus essential oils against potato late blight causative agent. Journal of Essential Oil Research, 27(2), 169-176.
• Thyme, origanum, clove, and orange essential oils were the most inhibitory against foodborne bacteria and yeasts. Cumin, tea tree, and mint also provided inhibition.  From:  Irkin, R., & Korukluoglu, M. (2009). Growth inhibition of pathogenic bacteria and some yeasts by selected essential oils and survival of L. monocytogenes and C. albicans in apple–carrot juice. Foodborne pathogens and disease, 6(3), 387-394.
• Orange, eucalyptus, fennel, geranium, juniper, peppermint, rosemary, purified turpentine, thyme, and Australian tea tree oil as well as the constituent of menthol showed antimicrobial and antiplasmid activities against the bacteria tested. From:  Schelz, Z., Molnar, J., & Hohmann, J. (2006). Antimicrobial and antiplasmid activities of essential oils. Fitoterapia, 77(4), 279-285.
• Cornmint, cumin, laurel, lemon peel, orange, oregano, and ziziphora were active against all of the tested bacteria to various degrees. From:  Kivanç, M., & Akgül, A. (1986). Antibacterial activities of essential oils from Turkish spices and citrus. Flavour and Fragrance Journal, 1(4‐5), 175-179.
• Citrus oils of orange, lemon, and bergamot may be an effective and safe antimicrobial additive in food.  From:  Fisher, K., & Phillips, C. (2008). Potential antimicrobial uses of essential oils in food: is citrus the answer? Trends in food science & technology, 19(3), 156-164.
• Citrus limon (lemon), Citrus paradisi (grapefruit), Citrus bergamia (bergamot), Citrus aurantium (bitter orange), Citrus sinensis (sweet orange), and Citrus reticulata (mandarin) showed antimicrobial activity against multiple bacteria, fungi, and candida species in vitro.  From:  Kirbaşlar, F. G., Tavman, A., Dülger, B., & Türker, G. (2009). Antimicrobial activity of Turkish Citrus peel oils. Pak J Bot, 41(6), 3207-12.
• Antifungal, anti-aflatoxigenic and antioxidant activity of Citrus maxima and Citrus sinensis essential oils were analyzed.  From:  Singh, P., Shukla, R., Prakash, B., Kumar, A., Singh, S., Mishra, P. K., & Dubey, N. K. (2010). Chemical profile, antifungal, antia  flatoxigenic and antioxidant activity of Citrus maxima Burm. and Citrus sinensis (L.) Osbeck essential oils and their cyclic monoterpene, DL-limonene. Food and Chemical Toxicology, 48(6), 1734-1740.
• Citrus vapour has a potential clinical application as a secondary disinfectant to reduce surface contamination of Enterococcus sp. and Staphylococcus aureus.  From:  Laird, K., Armitage, D., & Phillips, C. (2012). Reduction of surface contamination and biofilms of Enterococcus sp. and Staphylococcus aureus using a citrus-based vapour. Journal of Hospital Infection, 80(1), 61-66.
• A blend of orange (Citrus sinensis) and bergamot (Citrus bergamia) against Enterococcus species was bactericidal.  From:  Fisher, K., & Phillips, C. (2009). The mechanism of action of a citrus oil blend against Enterococcus faecium and Enterococcus faecalis. Journal of applied microbiology, 106(4), 1343-1349.
• Low concentrations of the lemon, orange, and mandarin essential oils along with a mild heat treatment showed synergistic lethal effects against spoiling and pathogenic food microorganisms.  From: Espina, L., Somolinos, M., Lorán, S., Conchello, P., García, D., & Pagán, R. (2011). Chemical composition of commercial citrus fruit essential oils and evaluation of their antimicrobial activity acting alone or in combined processes. Food control, 22(6), 896-902.
• L. angustifolia combined with Cinnamomum zeylanicum or Citrus sinensis was effective against C. albicans and S. aureus.  From: de Rapper, S., Kamatou, G., Viljoen, A., & van Vuuren, S. (2013). The in vitro antimicrobial activity of Lavandula angustifolia essential oil in combination with other aroma-therapeutic oils. Evidence-Based Complementary and Alternative Medicine, 2013.
• Out of 21 oils tested, cinnamon, clove, geranium, lemon, lime, orange and rosemary exhibited the strongest activity against the tested bacteria. From:  Prabuseenivasan, S., Jayakumar, M., & Ignacimuthu, S. (2006). In vitro antibacterial activity of some plant essential oils. BMC complementary and alternative medicine, 6(1), 1.
• Aegle, ageratum, citronella, eucalyptus, geranium, lemongrass, orange, palmarosa, patchouli and peppermint, were tested for antibacterial activity against 22 bacteria, and twelve fungi. From:  Pattnaik, S., Subramanyam, V. R., & Kole, C. (1995). Antibacterial and antifungal activity of ten essential oils in vitro. Microbios, 86(349), 237-246.
• Lemon, mandarin, grapefruit, and orange oils were antifungal against food spoilage molds.  From:  Viuda-Martos, M., Ruiz-Navajas, Y., Fernández-López, J., & Pérez-Álvarez, J. (2008). Antifungal activity of lemon (Citrus lemon L.), mandarin (Citrus reticulata L.), grapefruit (Citrus paradisi L.) and orange (Citrus sinensis L.) essential oils. Food control, 19(12), 1130-1138.
• Orange, lemon and mandarin showed antioxidant and antimicrobial activity in vitro.  From: Frassinetti, Stefania & Caltavuturo, L & Cini, Marianna & Della Croce, Clara & Maserti, Biancaelena. (2011). Antibacterial and Antioxidant Activity of Essential Oils from Citrus spp. Journal of Essential Oil Research – J ESSENT OIL RES. 23. 27-31. 10.
• From 22 essential oils tested, cornmint, cumin, laurel, lemon peel, orange, oregano, and Ziziphora were active against all assessed bacteria.  From:  Kivanç, M., & Akgül, A. (1986). Antibacterial activities of essential oils from Turkish spices and citrus. Flavour and Fragrance Journal, 1(4‐5), 175-179.
• This was a review of research on fungal treatments including tea tree, solanum species, and bitter orange oil.  From:  Martin, K. W., & Ernst, E. (2004). Herbal medicines for treatment of fungal infections: a systematic review of controlled clinical trials. Mycoses, 47(3‐4), 87-92.
• Orange extracts were antibacterial against Campylobacter jejuni, Campylobacter coli, and Arcobacter spp. From:  Nannapaneni, R., Chalova, V. I., Crandall, P. G., Ricke, S. C., Johnson, M. G., & O’Bryan, C. A. (2009). Campylobacter and Arcobacter species sensitivity to commercial orange oil fractions. International journal of food microbiology, 129(1), 43-49.
• Orange, grapefruit, mandarin, and tangarine essential oils demonstrated antioxidant and antimicrobial actions in vitro.  From:  Javed, S., Javaid, A., Nawaz, S., Saeed, M. K., Mahmood, Z., Siddiqui, S. Z., & Ahmad, R. (2014). Phytochemistry, GC-MS analysis, antioxidant and antimicrobial potential of essential oil from five citrus species. Journal of Agricultural Science, 6(3), 201.
• Stems from orange and lime trees have been used as chewing sticks to clean teeth and freshen breathe. In vitro studies showed extracts of Citrus sinensis and Citrus aurantifolia were active against pathogens found on teeth. From: Nata’ala, M. K., Dalhat, M. H., Omoye, B. S., Isah, A. A., Kabiru, S., Bashiru, I., & Umar, F. A. (2018). Phytochemical Screening and Antibacterial Activity of Citrus sinensis (L.) Osbeck [Orange] and Citrus aurantifolia (Cristm.) Swingle [Lime] Stem from Bacteria Associated with Dental Caries. Journal of Advances in Microbiology, 1-9.
• Citrus essential oils showed a variety of effectiveness against foodborne pathogens in vitro. From: Restuccia, C., Conti, G. O., Zuccarello, P., Parafati, L., Cristaldi, A., & Ferrante, M. (2019). Efficacy of different citrus essential oils to inhibit the growth and B1 aflatoxin biosynthesis of Aspergillus flavus. Environmental Science and Pollution Research, 1-10.
• In a case study of a 63 year old women, a recipe with arrow root powder, baking soda, and essential oils of basil, tea tree, sage, and clove reduced foot bacteria and fungus.  From:  Misner, B. D. (2007). A novel aromatic oil compound inhibits microbial overgrowth on feet: a case study. Journal of the International Society of Sports Nutrition, 4(1), 3.
• The following essential oils and blends showed antifungal action against Trichophyton interdigitale when applied to cotton: oregano, cinnamon, and the combination of origanum/clove/orange and clove/lavender/cinnamon. This may be useful in making footwear to prevent foot fungus. From:   Berechet, M. D., Chirilă, C., & Deselnicu, V. (2016). Antifungal Activity of Some Essential Oils on Cotton Fabrics. In International Conference on Advanced Materials and Systems (ICAMS) (pp. 197-202). The National Research & Development Institute for Textiles and Leather-INCDTP.
• A blend of cinnamon bark, clove bud, sweet orange, eucalyptus, and rosemary essential oils reduced flu virus activity in vitro. From: Wu, S., Patel, K. B., Booth, L. J., Metcalf, J. P., Lin, H. K., & Wu, W. (2010). Protective essential oil attenuates influenza virus infection: an in vitro study in MDCK cells. BMC complementary and alternative medicine, 10(1), 69.

ANTIOXIDANT

• In a summary of research, it was concluded that flavonoids from citrus fruits have antioxidant activity that may help reduce disease like cancer and inflammation. From: Asjad, H. M. M., Akhtar, M. S., Bashir, S., Din, B., Gulzar, F., Khalid, R., & Asad, M. (2013). Phenol, flavonoid contents and antioxidant activity of six common citrus plants in Pakistan. Journal of Pharmaceutical and Cosmetic Sciences, 1(1), 1-5.
• Flavonoids and other constituents isolated from citrus demonstrated antioxidant activities in vitro. From: Yu, J., Wang, L., Walzem, R. L., Miller, E. G., Pike, L. M., & Patil, B. S. (2005). Antioxidant activity of citrus limonoids, flavonoids, and coumarins. Journal of agricultural and food chemistry, 53(6), 2009-2014.
• In a summary of research, hesperidin is a bioflavonoid found in high concentrations in citrus fruit with a significant anti-inflammatory and antioxidant effect. From: Tejada, S., Pinya, S., Martorell, M., Capó, X., Tur, J. A., Pons, A., & Sureda, A. (2018). Potential anti-inflammatory effects of hesperidin from the genus Citrus. Current medicinal chemistry, 25(37), 4929-4945.
• Phenolic components from citrus fruits showed antioxidant, hypoglycemic, hypotensive activities in vitro.   From: Alu’Datt, M. H., Rababah, T., Alhamad, M. N., Al-Mahasneh, M. A., Ereifej, K., Al-Karaki, G., … & Ghozlan, K. A. (2017). Profiles of free and bound phenolics extracted from Citrus fruits and their roles in biological systems: content, and antioxidant, anti-diabetic and anti-hypertensive properties. Food & function, 8(9), 3187-3197.
• This study associated phenolic content with antioxidant activity in Citrus sinensis and Citrus aurantium.  From:  Lagha-Benamrouche, S., & Madani, K. (2013). Phenolic contents and antioxidant activity of orange varieties (Citrus sinensis L. and Citrus aurantium L.) cultivated in Algeria: Peels and leaves. Industrial Crops and Products, 50, 723-730.
• Orange, lemon and mandarin showed antioxidant and antimicrobial activity in vitro.  From: Frassinetti, Stefania & Caltavuturo, L & Cini, Marianna & Della Croce, Clara & Maserti, Biancaelena. (2011). Antibacterial and Antioxidant Activity of Essential Oils from Citrus spp. Journal of Essential Oil Research – J ESSENT OIL RES. 23. 27-31. 10.
• Essential oil from the peel and seeds of sweet orange demonstrated antioxidant and brain protective abilities in vitro. This could be useful related to Alzheimer’s disease. From: Ademosun, A. O., Oboh, G., Olupona, A. J., Oyeleye, S. I., Adewuni, T. M., & Nwanna, E. E. (2016). Comparative Study of Chemical Composition, In Vitro Inhibition of Cholinergic and Monoaminergic Enzymes, and Antioxidant Potentials of Essential Oil from Peels and Seeds of Sweet Orange (C itrus Sinensis [L.] Osbeck) Fruits. Journal of food biochemistry, 40(1), 53-60.
• In a summary of research, hesperidin is a bioflavonoid found in high concentrations in citrus fruit with a significant anti-inflammatory and antioxidant effect. From: Tejada, S., Pinya, S., Martorell, M., Capó, X., Tur, J. A., Pons, A., & Sureda, A. (2018). Potential anti-inflammatory effects of hesperidin from the genus Citrus. Current medicinal chemistry, 25(37), 4929-4945.

INSECTICIDAL / REPELLENT

• Phytochemical extracts from citrus fruit peels (Citrus sinensis, Citrus limonum,Citrus aurantifolia, Citrus reticulata and Citrus vitus) at a dilution of 20-25% applied topically on human volunteers repelled insects for 2-5 hours.  From:  Effiom, O. E., Avoaja, D. A., & Ohaeri, C. C. (2012). Mosquito repellent activity of phytochemical extracts from peels of citrus fruit species. Global J Sci Front Res Interdisc, 12(1).
• Apium graveolens (celery), Citrus sinensis (orange), Eucalyptus globulus (eucalyptus), Juniperus oxycedrus (juniper), Laurus nobilis (bay), Lavandula hybrida (lavender), Mentha microphylla (mint), Mentha viridis (spearmint), Ocimum basilicum (basil), Origanum vulgare (oregano), Pistacia terebinthus (turpentine tree), Rosmarinus officinalis (rosemary), and Thuja orientalis (thuja) were effective insect repellents against Acanthoscelides obtectus.  From:  Papachristos, D. P., & Stamopoulos, D. C. (2002). Repellent, toxic and reproduction inhibitory effects of essential oil vapours on Acanthoscelides obtectus (Say)(Coleoptera: Bruchidae). Journal of Stored Products Research, 38(2), 117-128.
• The insecticidal activities of essential oil extracts against the mosquito Culex pipiens molestus Forskål were determined. Extracts of Foeniculum vulgare (fennel) were the most toxic, followed by Ferula hermonis Boiss (in the carrot family), Citrus sinensis (orange), Pinus pinea (pine), Laurus nobilis (bay), and Eucalyptus spp. Terpineol and 1,8-cineole components were the most effective in preventing Culex pipiens molestus bites.   From:  Traboulsi, A. F., El‐Haj, S., Tueni, M., Taoubi, K., Nader, N. A., & Mrad, A. (2005). Repellency and toxicity of aromatic plant extracts against the mosquito Culex pipiens molestus (Diptera: Culicidae). Pest management science, 61(6), 597-604.
• Orange oil was active against the Formosan subterranean termite.  From:  Raina, A., Bland, J., Doolittle, M., Lax, A., Boopathy, R., & Folkins, M. (2007). Effect of orange oil extract on the Formosan subterranean termite (Isoptera: Rhinotermitidae). Journal of economic entomology, 100(3), 880-885.
• Citrus sinensis, Citrus limon and Citrus aurantifolia peels extracts were effective against termites. From: Ito, E., & Ukpohwo, R. (2018). Termiticidal Efficacy of Citrus Peel Extracts against Termites (Macrotermes bellicosus). Journal of Biological Studies, 1(3), 98-105.
• These tested citrus essential oils are listed in order of repelling effectiveness against two mosquito species when applied to human skin: C. aurantifolia, C. microcarpa, C. maxima, C. reticulate, C. sinensis, C. hystrix, C. aurantium, and C. medica var sarcodaclylis. From: Soonwera, M. (2015). Efficacy of essential oils from Citrus plants against mosquito vectors Aedes aegypti (Linn.) and Culex quinquefasciatus (Say). Journal of Agricultural Technology, 11(3), 669-681.

ANTI-PARASITE

• Citrus sinensis and Melaleuca quinquenervia showed varying anthelmintic activity against gastrointestinal nematodes with 1,8-cineole and limonene being active constituents.  Amounts needed to by anti-parasitic may not have been safe for the host; more research is necessary.   From:  Gaínza, Y. A., Domingues, L. F., Perez, O. P., Rabelo, M. D., López, E. R., & de Souza Chagas, A. C. (2015). Anthelmintic activity in vitro of Citrus sinensis and Melaleuca quinquenervia essential oil from Cuba on Haemonchus contortus. Industrial Crops and Products, 76, 647-652.

CHOLESTEROL LOWERING

• Orange and grapefruit reduced cholesterol in rats.  From:  Mallick, N., & Khan, R. A. (2016). Antihyperlipidemic effects of Citrus sinensis, Citrus paradisi, and their combinations. Journal of pharmacy & bioallied sciences, 8(2), 112.
• A compilation of research showed the following herbs to have a hypolipidemic effect:  yarrow, onion, garlic, dill, celery, burdock, oats, barberry, cabbage, chili pepper, safflower, chicory, chickpea, bitter orange, orange, guggul, coriander, cranberry, melon, pumpkin, artichoke, ginseng, eugenol, schelelecht, ginkgo, soy, walnut, apple, nutmeg, red yeast rice, miswak, evening primrose, basil, bulacy, orchis, avocado, plantain, blond plotitago, green bean, purslane, black cherry, pomegranate, milk thistle, brinjal, tomato, tamarind, thea, thyme, fenugreek, bilberry, grape, ginger, and corn.  From:  Rouhi-Boroujeni, H., Rouhi-Boroujeni, H., Khoddami, M., Khazraei, H. R., Dehkordil, E. B., & Rafieian-Kopaei, M. (2017). Hypolipidemic herbals with diuretic effects: A systematic review. In Biol. Sci (Vol. 8, pp. 21-28).

ANTI-CANCER / ANTI-TUMOR

• In a review of 17 studies, it was concluded that intake of citrus fruits was associated with a 50% reduction of risk in cavity and pharyngeal cancer. From: Cirmi, S., Navarra, M., Woodside, J. V., & Cantwell, M. M. (2018). Citrus fruits intake and oral cancer risk: A systematic review and meta-analysis. Pharmacological research, 133, 187-194.
• Citrus oils of sweet orange, grapefruit, and lemon induced apoptosis of human leukemia cancer tumor cells and limonene, decanal, octonal and citral showed strong apoptotic activity.  From:  Hata, T., Sakaguchi, I., Mori, M., Ikeda, N., Kato, Y., Minamino, M., & Watabe, K. (2002). Induction of apoptosis by Citrus paradisi essential oil in human leukemic (HL-60) cells. In vivo (Athens, Greece), 17(6), 553-559

ANXIOLITIC

• In a review of nine clinical studies, it was concluded that the aroma of both neroli and orange has an anxiolytic effect.  From:  Mannucci, C., Calapai, F., Cardia, L., Inferrera, G., D’Arena, G., Di Pietro, M., … & Calapai, G. (2018). Clinical Pharmacology of Citrus aurantium and Citrus sinensis for the Treatment of Anxiety. Evidence-Based Complementary and Alternative Medicine, 2018.
• In a randomized clinical trial of 150 children ages 8-12, groups who received aromatherapy of lavender or sweet orange via a nebulizing diffuser or inhaler demonstrated less pain and anxiety associated with dental procedures.  From: Nirmala, K., & Kamatham, R. (2021). Effect of Aromatherapy on Dental Anxiety and Pain in Children Undergoing Local Anesthetic Administrations: A Randomized Clinical Trial. Journal of Caring Sciences, 10(3), 111.
• In a study of 51 volunteers going through crack cocaine drug withdrawal, diffusing the the EO of Citrus aurantium reduced anxiety.  From:  Chaves Neto, G., Braga, J. E. F., Alves, M. F., de Morais Pordeus, L. C., Santos, S. G. D., Scotti, M. T., … & Diniz, M. D. F. F. M. (2017). Anxiolytic Effect of Citrus aurantium L. in Crack Users. Evidence-Based Complementary and Alternative Medicine, 2017.
• In a study of 56 patients with anxiety related to their dental surgery, blood pressure, pulse rate, and respiratory rate were significantly lower in the group who inhaled orange aroma compared to the placebo.  From:  Hasheminia, D., Motamedi, M. R. K., Ahmadabadi, F. K., Hashemzehi, H., & Haghighat, A. (2014). Can ambient orange fragrance reduce patient anxiety during surgical removal of impacted mandibular third molars? Journal of Oral and Maxillofacial Surgery, 72(9), 1671-1676.
• Results showed an acute anxiolytic activity of sweet orange aroma in humans.  From:  Goes, T. C., Antunes, F. D., Alves, P. B., & Teixeira-Silva, F. (2012). Effect of sweet orange aroma on experimental anxiety in humans. The Journal of Alternative and Complementary Medicine, 18(8), 798-804.
• In a small study involving 20 male students, inhaling a ginger and citrus aroma while sleeping reduced cortisol secretion levels in saliva that are associated with stress.  From:  Jiang, F., Kobayashi, T., Ichihashi, T., Ito, K., & Nomura, S. (2018). The effect of citrus ginger aroma on heart rate and salivary cortisol level during sleep at home. IEEJ Transactions on Electrical and Electronic Engineering.
• In a study, 70 elderly women wore an aromatherapy necklace for 4 weeks with orange and marjoram.  It improved sleep and reduced anxiety compared to the placebo.  From:  Chun, N., & Kim, M. (2017). Effects of a Sleep Improvement Program Combined with Aroma-Necklace on Sleep, Depression, Anxiety and Blood Pressure in Elderly Women. Journal of Korean Academy of Nursing, 47(5), 651-662.
• Orange and lavender aromatherapy reduced anxiety and improved mood in patients waiting for dental treatment.  From:  Lehrner, J., Marwinski, G., Lehr, S., Johren, P., & Deecke, L. (2005). Ambient odors of orange and lavender reduce anxiety and improve mood in a dental office. Physiology & Behavior, 86(1), 92-95.
• In a study of 80 female students, both the aroma of lavender and the aroma of orange reduced test taking anxiety compared to the placebo.  From:  Bakhsha, F., Yousefi, Z., Aryaee, M., & Jafari, S. Y. (2016). Comparison effect of Lavender and Citrus aurantium aroma on anxiety in female students at Golestan University of Medical Sciences. Journal of Basic Research in Medical Sciences, 3(4), 4-11.
• In a study of 14 stroke patients, a footbath and massage with juniper, lavender, rosemary, patchouli, and orange reduced stress, improved mood, increased body temperature, and improved sleeping satisfaction compared to the placebo.  From:  Lee, J. H., Seo, E. K., Shim, J. S., & Chung, S. P. (2017). The effects of aroma massage and foot bath on psychophysiological response in stroke patients. Journal of physical therapy science, 29(8), 1292-1296.
• In a study of menopausal women, ingestion of bitter orange and lavender flower powders significantly reduced anxiety compared to the placebo.  From: Farshbaf-Khalili, A., Kamalifard, M., & Namadian, M. (2018). Comparison of the effect of lavender and bitter orange on anxiety in postmenopausal women: A triple-blind, randomized, controlled clinical trial. Complementary therapies in clinical practice, 31, 132-138.
• Rats had an acute anxiolytic effect from sweet orange essence. From:  Faturi, C. B., Leite, J. R., Alves, P. B., Canton, A. C., & Teixeira-Silva, F. (2010). Anxiolytic-like effect of sweet orange aroma in Wistar rats. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 34(4), 605-609.
• Inhalation of Citrus sinensis essential oil for 30 minutes had an anxiolytic effect in mice.  From:  Wolffenbüttel, A. N., Zamboni, A., Becker, G., dos Santos, M. K., Borille, B. T., de Cássia Mariotti, K., … & de Moura Linck, V. (2018). Citrus essential oils inhalation by mice: Behavioral testing, GCMS plasma analysis, corticosterone, and melatonin levels evaluation. Phytotherapy Research, 32(1), 160-169.

INSOMNIA

• In a study, 70 elderly women wore an aromatherapy necklace for 4 weeks with orange and marjoram.  It improved sleep and reduced anxiety compared to the placebo.  From:  Chun, N., & Kim, M. (2017). Effects of a Sleep Improvement Program Combined with Aroma-Necklace on Sleep, Depression, Anxiety and Blood Pressure in Elderly Women. Journal of Korean Academy of Nursing, 47(5), 651-662.
• In a study of 14 stroke patients, a footbath and massage with juniper, lavender, rosemary, patchouli, and orange reduced stress, improved mood, increased body temperature, and improved sleeping satisfaction compared to the placebo.  From:  Lee, J. H., Seo, E. K., Shim, J. S., & Chung, S. P. (2017). The effects of aroma massage and foot bath on psychophysiological response in stroke patients. Journal of physical therapy science, 29(8), 1292-1296.

DEPRESSION

• In a study, 70 elderly women wore an aromatherapy necklace for 4 weeks with orange and marjoram.  It improved sleep and reduced anxiety compared to the placebo.  From:  Chun, N., & Kim, M. (2017). Effects of a Sleep Improvement Program Combined with Aroma-Necklace on Sleep, Depression, Anxiety and Blood Pressure in Elderly Women. Journal of Korean Academy of Nursing, 47(5), 651-662.
• In a study of 14 stroke patients, a footbath and massage with juniper, lavender, rosemary, patchouli, and orange reduced stress, improved mood, increased body temperature, and improved sleeping satisfaction compared to the placebo.  From:  Lee, J. H., Seo, E. K., Shim, J. S., & Chung, S. P. (2017). The effects of aroma massage and foot bath on psychophysiological response in stroke patients. Journal of physical therapy science, 29(8), 1292-1296.

COMMON COLD

• In a large double-blind study, vitamin C reduced the duration and symptoms of the common cold.  From:  Anderson, T. W., Reid, D. B. W., & Beaton, G. H. (1972). Vitamin C and the common cold: a double-blind trial. Canadian Medical Association Journal, 107(6), 503.

ORAL HEALTH

• Stems from orange and lime trees have been used as chewing sticks to clean teeth and freshen breathe. In vitro studies showed extracts of Citrus sinensis and Citrus aurantifolia were active against pathogens found on teeth. From: Nata’ala, M. K., Dalhat, M. H., Omoye, B. S., Isah, A. A., Kabiru, S., Bashiru, I., & Umar, F. A. (2018). Phytochemical Screening and Antibacterial Activity of Citrus sinensis (L.) Osbeck [Orange] and Citrus aurantifolia (Cristm.) Swingle [Lime] Stem from Bacteria Associated with Dental Caries. Journal of Advances in Microbiology, 1-9.

IMPROVED COGNITION

• Aromatherapy of rosemary and lemon essential oils in the morning, and lavender and orange in the evening improved cognition of Alzheimer’s patients.  From:  Jimbo, D., Kimura, Y., Taniguchi, M., Inoue, M., & Urakami, K. (2009). Effect of aromatherapy on patients with Alzheimer’s disease. Psychogeriatrics, 9(4), 173-179.
• Juices from grapefruit and sweet orange improved cognitive performance and memory in mice. From: Mallick, N., Anjum, F., Ali, H., & Bano, N. (2018). MEMORY BOOSTING EFFECT OF CITRUS JUICES.

STIMULANT

• A blend of Santalum album, Citrus aurantium, Citrus limonum, Styrax benzoin, Citrus paradisi, Mentha piperata, Acori tatarinowii rhizoma, Rhodiolae crenulatae radix et rhizoma, and Camellia sinensis aromatherapy at night reduced fatigue in rodents.  It enhanced physical endurance, improved cognition, reduced negative emotion and decrease anxiety. From:  Han, C., Li, F., Tian, S., Liu, Y., Xiao, H., Wu, X., … & Mao, M. (2018). Beneficial effect of compound essential oil inhalation on central fatigue. BMC complementary and alternative medicine, 18(1), 309.

ASTHMA

• In a large review of over 4000 children showed eating citrus and kiwi reduced asthma and wheezing symptoms.  From:  Forastiere, F., Pistelli, R., Sestini, P., Fortes, C., Renzoni, E., Rusconi, F., … & SIDRIA Collaborative Group. (2000). Consumption of fresh fruit rich in vitamin C and wheezing symptoms in children. Thorax, 55(4), 283-288.

DIGESTIVE AID

• In a review of research, eating citrus fruits help reduce inflammatory bowel disease. From: Musumeci, L., Maugeri, A., Cirmi, S., Lombardo, G. E., Russo, C., Gangemi, S., … & Navarra, M. (2019). Citrus fruits and their flavonoids in inflammatory bowel disease: an overview. Natural product research, 1-15.
• In a review of research, flavones from citrus fruits can help improve digestive health. From: Stevens, Y., Rymenant, E. V., Grootaert, C., Camp, J. V., Possemiers, S., Masclee, A., & Jonkers, D. (2019). The Intestinal Fate of Citrus Flavanones and Their Effects on Gastrointestinal Health. Nutrients, 11(7), 1464.

NEUROPROTECTIVE

• Essential oil from the peel and seeds of sweet orange demonstrated antioxidant and brain protective abilities in vitro. This could be useful related to Alzheimer’s disease. From: Ademosun, A. O., Oboh, G., Olupona, A. J., Oyeleye, S. I., Adewuni, T. M., & Nwanna, E. E. (2016). Comparative Study of Chemical Composition, In Vitro Inhibition of Cholinergic and Monoaminergic Enzymes, and Antioxidant Potentials of Essential Oil from Peels and Seeds of Sweet Orange (C itrus Sinensis [L.] Osbeck) Fruits. Journal of food biochemistry, 40(1), 53-60.

ANTI-DIABETIC

• In a review of research, flavone glycosides (naringin, hesperidin, and diosmin) found in citrus fruit have an anti-diabetic effect. From: Srinivasan, S., Vinothkumar, V., & Murali, R. (2019). Antidiabetic Efficacy of Citrus Fruits with Special Allusion to Flavone Glycosides. In Bioactive Food as Dietary Interventions for Diabetes (pp. 335-346). Academic Press.
• Phenolic components from citrus fruits showed antioxidant, hypoglycemic, hypotensive activities in vitro.   From: Alu’Datt, M. H., Rababah, T., Alhamad, M. N., Al-Mahasneh, M. A., Ereifej, K., Al-Karaki, G., … & Ghozlan, K. A. (2017). Profiles of free and bound phenolics extracted from Citrus fruits and their roles in biological systems: content, and antioxidant, anti-diabetic and anti-hypertensive properties. Food & function, 8(9), 3187-3197.

HYPOTENSIVE

• Phenolic components from citrus fruits showed antioxidant, hypoglycemic, hypotensive activities in vitro.   From: Alu’Datt, M. H., Rababah, T., Alhamad, M. N., Al-Mahasneh, M. A., Ereifej, K., Al-Karaki, G., … & Ghozlan, K. A. (2017). Profiles of free and bound phenolics extracted from Citrus fruits and their roles in biological systems: content, and antioxidant, anti-diabetic and anti-hypertensive properties. Food & function, 8(9), 3187-3197.

PRESERVATIVE

• Citrus essential oils showed a variety of effectiveness against foodborne pathogens in vitro. From: Restuccia, C., Conti, G. O., Zuccarello, P., Parafati, L., Cristaldi, A., & Ferrante, M. (2019). Efficacy of different citrus essential oils to inhibit the growth and B1 aflatoxin biosynthesis of Aspergillus flavus. Environmental Science and Pollution Research, 1-10.

SPASMOLYTIC

• Carvone and limonene showed involuntary muscle spasmolytic activity in vitro. From: de Sousa, D. P., Mesquita, R. F., de Araújo Ribeiro, L. A., & de Lima, J. T. (2015). Spasmolytic activity of carvone and limonene enantiomers. Natural product communications, 10(11), 1934578X1501001120.

PAIN

• In a double-blind placebo-controlled study of 59 elderly people with chronic knee pain, six massage sessions were given with oils of ginger and orange over a 3-week period vs just plain olive oil for the control group.  The aromatic group showed significant improvements in nee pain intensity, stiffness, and physical function.  From: Yip, Y. B., & Tam, A. C. Y. (2008). An experimental study on the effectiveness of massage with aromatic ginger and orange essential oil for moderate-to-severe knee pain among the elderly in Hong Kong. Complementary therapies in medicine, 16(3), 131-138.
• In a randomized small controlled study with nurses after two consecutive days of working, both a foot bath or a topical spray with peppermint and orange essential oils helped reduce lower extremity edema, pain, and fatigue.  From: Han, A., Kim, J., & Hur, M. H. (2022). Effects of Foot Bath and Spray Application of Peppermint and Grapefruit Essential Oils on Lower Extremity Edema, Pain, and Fatigue. Journal of the Korea Convergence Society, 13(1), 375-386.
• In a randomized clinical trial of 150 children ages 8-12, groups who received aromatherapy of lavender or sweet orange via a nebulizing diffuser or inhaler demonstrated less pain and anxiety associated with dental procedures.  From: Nirmala, K., & Kamatham, R. (2021). Effect of Aromatherapy on Dental Anxiety and Pain in Children Undergoing Local Anesthetic Administrations: A Randomized Clinical Trial. Journal of Caring Sciences, 10(3), 111.

ATHLETE’S FOOT

• The following essential oils and blends showed antifungal action against Trichophyton interdigitale when applied to cotton: oregano, cinnamon, and the combination of origanum/clove/orange and clove/lavender/cinnamon. This may be useful in making footwear to prevent foot fungus. From:   Berechet, M. D., Chirilă, C., & Deselnicu, V. (2016). Antifungal Activity of Some Essential Oils on Cotton Fabrics. In International Conference on Advanced Materials and Systems (ICAMS) (pp. 197-202). The National Research & Development Institute for Textiles and Leather-INCDTP.

By: Kathy Sadowski

Updated: 12/21/2022