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African potato (Hypoxis hemerocallidea): a systematic review of its chemistry, pharmacology and ethno medicinal properties



African Potato (hypoxis hemerocallidea), is used for enhancing immune system in Southern Africa. It is among the plants of intense commercial and scientific interest; hence, the aim of this study was to describe its chemistry and pharmacology.


PubMed, Cochrane Controlled Trials Register (CENTRAL) and Google Scholar were searched independently for relevant literature. The last search occurred in October 2018. Other research material was obtained from Google. The following search terms were used, but not limited to: “African Potato”, “hypoxis”, “hemerocallidea”, “rooperol.” Articles that were explaining the chemistry and pharmacology of hypoxis hemerocallidea were included.


Thirty articles from PubMed, Cochrane and Google Scholar were eligible. Three webpages were included from Google. Results showed that the tuberous rootstock (corm) of African Potato is used traditionally to treat wasting diseases, testicular tumours, insanity, barrenness, impotency, bad dreams, intestinal parasites, urinary infection, cardiac disease and enhancing immunity. The plant contains hypoxoside, which is converted rapidly to a potent antioxidant, rooperol in the gut. The corm contains sterols, sterol glycosides, stanols, terpenoids, saponins, cardiac glycosides, tannins and reducing sugars. A dose of 15 mg/kg/day of hypoxoside is reportedly therapeutic. Preclinical studies of African Potato have shown immunomodulation, antioxidant, antinociceptive, hypoglycaemic, anti-inflammatory, anticonvulsant, antibacterial, uterolytic, antimotility, spasmolytic and anticholinergic effects. The common side effects of African Potato are nausea and vomiting, which subside over time. In vitro, African Potato demonstrated inhibitory effects on CYP1A2, 2C9, 2D6, 3A4, 3A5, CYP19-metabolism and induction of P-glycoprotein. In vivo, it did not alter the pharmacokinetics of efavirenz or lopinavir/ritonavir.


African Potato is mainly used as an immunostimulant. The exact mechanisms of action for all the pharmacological actions are unknown. More research is required to substantiate claims regarding beneficial effects. There are many research gaps that require investigation including pharmacokinetic interactions with conventional drugs, especially those used in HIV/AIDS.

Peer Review reports


Medicines from natural sources have increased in popularity over orthodox medicines. Natural plants offer vast chemical diversity, which produce physiological changes in the human body [1]. In 2016, the worldwide annual market for herbal medicines was valued just above US$ 71 billion, and global health debates are focusing on traditional medicines [2]. Traditional medicines were used in historical eras and in populations in Africa, Asia, and Latin America and continue to be used due to cultural beliefs [3]. In the year 2002, severe acute respiratory syndrome (SARS) became a global disease outbreak, first appearing in China [4]. Many emergency measures were taken but there was no effective treatment [5]. The World Health Organization (WHO) reported that traditional medicine played a prominent role in the strategy to eradicate SARS in China. By late July 2003, no new cases were being reported [4].

Eighty percent of Africans use some form of traditional medicine [3] and the highest prevalence is among people living with HIV/ AIDS (PLWHA) [6, 7]. African Potato is one of the medicinal plants used for the management of human immunodeficiency virus (HIV) symptoms in Southern Africa. Its use in Africa is widespread and it is among the medicinal plants of intense commercial and scientific interest [8, 9].

African Potato, scientifically known as hypoxis hemerocallidea syn. Hypoxis rooperi belongs to the Hypoxidaceae family. Other common names include star lily, magic muthi or yellow stars [9]. The plant grows in the wild and is most prevalent in Southern Africa (mainly South Africa, Lesotho, Mozambique, and Zimbabwe). It is also found further into East Africa. The African Potato plant is easily identified by its star-shaped bright yellow flowers and green strap-like leaves. The tuberous rootstock (corm) is traditionally used to treat a wide variety of ailments. Extracts of the corm are used to make decoctions, which are taken as tonics against wasting diseases, tuberculosis, testicular tumors, other cancers, and HIV/ acquired immunodeficiency syndrome (AIDS) [10]. Traditionally, African Potato was used for insanity, barrenness, bad dreams, intestinal parasites, urinary infection and cardiac diseases among other diseases [11]. Nowadays it is used to increase immune function, for headache, dizziness, prostate hypertrophy, burns, and ulcers [10].

Albrecht, who thoroughly researched on African Potato, administered a methanolic extract of H. hemerocallidea to patients with HIV over 2 years in the mid-1990s. He reported that the CD4+ lymphocyte counts in these patients remained stable, while the serum p24 HIV antigen decreased and there was a decrease in expression of the HLA-DR CD8+ lymphocyte activation marker [12]. The HLA-DR CD8+ is used for identification of T lymphocytes and elevated levels are observed in HIV infection [13]. Albrecht concluded: “these studies have demonstrated that rooperol has potent, diverse and important pharmacological properties relevant to cancer, inflammation and HIV” [12].

The aim of this paper is to describe the chemistry, pharmacology and clinical properties of African Potato. Other objectives include identifying research areas for further study of the plant due to its widespread scientific interest. Reviewing the studies conducted on African Potato will reveal areas of further research.


This systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines [14]. A detailed literature review was conducted to describe the chemistry, pharmacology, clinical properties and pharmacologic claims made against African Potato.

Identification of articles

The literature search was done using PubMed, Cochrane Controlled Trials Register (CENTRAL) and Google Scholar. These databases were searched independently for relevant literature through October 2018. The search was re-run on 16 May 2019 and no new studies were found. Other research material was obtained from open searches using Google. The following MeSH (Medical Subject Headings) terms and keywords were used, but not limited to: “African Potato” OR “hypoxis” OR “hemerocallidea” OR “rooperol”. An example of the search details in PubMed is given below: “African Potato”[All Fields] OR “hypoxis”[MeSH Terms] OR “hemerocallidea”[All Fields] OR “rooperol” (Supplementary Concept).

Eligibility criteria

The material that described the chemistry, uses and pharmacology of hypoxis hemerocallidea were included. Other plant species were not included. The “sort by relevance” feature in Google Scholar was used; and where applicable, current articles and websites were selected for discussion. We did not restrict publication date. Clinical trials were included in the search. Table 1 shows the inclusion/ exclusion criteria.

Table 1 Inclusion/ exclusion criteria

Results and discussion

Thirty-three articles were used for data collection. Figure 1 shows the flow diagram for the data collection. The general characteristics of the articles and the data extracted are shown in Table 2.

Fig. 1
figure 1

PRISMA flow chart

Table 2 General characteristics of included studies

Pharmacology and chemistry

Hypoxis species have been reported to produce a variety of phytoglycosides; extensive research has been focused on the norlignan diglycoside hypoxoside and its aglycon rooperol. The main glycoside that is isolated from the Hypoxis spp. is hypoxoside [21]. Following oral administration, hypoxoside is metabolized in the gut to rooperol by β-glucosidase. There are two glucose units at the ends of two benzene rings on hypoxoside [10]. These units are oxidized by β-glucosidase to form the aglycone, rooperol. The enzyme β-glucosidase is found mostly in the gastrointestinal tract (GIT) and is released by rapidly dividing cancer cells. Rooperol is the biologically active compound that is associated with claims of medicinal properties [11].

Other constituents in hypoxis include various sterols and their glycosides, and these may have biological importance. H. hemerocallidea contains β-sitosterol (BSS), β-sitosterol glucoside (BSSG), campesterol and stigmasterol [39]. These plant sterols (phytosterols) have biologic roles in animal and human health. Phytosterols are incorporated into functional foods and inhibit the absorption of cholesterol from the diet. They also have prophylactic and therapeutic uses in hypercholesterolemia, cardiovascular disease and atherosclerosis [40].

Among the phytosterols, β-sitosterol and its glycoside have been studied most for their pharmacological effects [41]. In vitro, the combination of BSS and BSSG indicated anti-inflammatory effects mediated by the inhibition of interleukin 6 and tumor necrosis factor secretion. The anti-inflammatory effects of the mixture relieved rheumatoid arthritis in humans. Another small pilot study reported that the BSS/ BSSG mixture resulted in significant improvement in allergic rhinitis/sinusitis after 12 weeks and this was attributed to immunological changes in the cytokine profiles produced by lymphocytes [40]. In vitro, phytosterols can affect different levels of tumor development and they have immune-modulating properties [41]. Phytosterols initiated programmed cell death (apoptosis) in human colon cancer, breast cancer, and prostate cancer. The probable mechanism was the activation of the protein phosphatase A2 pathway and the sphingomyelin cycle [22].

Rat models suggest that phytosterols may offer protection against breast, colon and prostate cancer [39]. In Phase I clinical trials, BSS has proven to be safe [15]. Sitosterols are poorly absorbed from the gastrointestinal tract. In humans, oral bioavailability is no more than 5% and it is 9% in dogs [23]. However, with advanced formulation technology many targeted drug delivery systems may provide alternative approaches for compounds with low bioavailability [45]. If successful, targeted delivery systems could aid in the delivery of phytosterols to facilitate clinical trials. An important knowledge gap is the drug interactions that may occur in immunocompromised patients who require many other medications (polypharmacy).

In another study, domestic cats were infected with a model of HIV. Cats treated with phytosterols maintained stable CD4 cell counts compared to placebo; the mortality between the two groups was significantly different [24]. In humans, an open-label study compared the efficacy of BSS/ BSSG with placebo in HIV infected treatment-naïve patients. During the time of the study, antiretroviral treatment (ART) was not affordable to most patients. Within 12 months, patients with > 500 CD4 cells/ μl at baseline maintained their CD4 cell count and plasma viral loads were significantly decreased. Those with advanced HIV at baseline (< 200 CD4 cells/ μl) still had disease progression. Patients in the BSS/ BSSG arm maintained a favorable TH1 response and their cell-mediated immunity was likely to be responsible for their response [20]. These findings concur with clinical trials that were conducted later that early initiation of ART delays the time to AIDS events [46]. In addition, there should be more research on herbs that enhance immune function in immunocompromised individuals to slow the progression of the disease. Again, due to polypharmacy, possible drug-herb interactions should be considered. Phytosterols are associated with faster clinical recovery in pulmonary tuberculosis [16] and possess anti-inflammatory, wound healing, analgesic, anti-helminthic, anti-mutagenic, anti-oxidant, neuroprotective and anti-diabetic properties [41].

There is limited knowledge on other secondary metabolites of hypoxis. As of 17 October 2018, a literature search found one study in Zimbabwe that compared the phytochemical profiles and cytotoxicity of four species of hypoxis. These were H. hemerocallidea, H. rigidula, H. galpinii and H. obtuse. Although this study did not quantify the phytochemicals, corm extracts of all four species indicated the presence of terpenoids, saponins, cardiac glycosides, tannins and reducing sugars. All species screened negative for alkaloids, flavonoids, and anthraquinones [1]. In other plant species, these phytochemicals are claimed to have curative activity against several pathogens [47]. The phytochemicals identified in this study can be attributed to the biologic activities of hypoxis. Terpenoids have antimicrobial and antioxidant properties and they are explored as cytotoxic and antineoplastic agents [48]. Saponins from plant sources have various pharmacologic effects like antimicrobial, anticancer, anthelmintic, antioxidant, antidiabetic, anticonvulsant, analgesic, antispasmodic, hypocholesterolemic, antitussive and cytotoxic activities [49]. Cardiac glycosides inhibit the Na+/K+ pump thus slow the heart rate and increase the contractility of the heart muscle. Although they improve the cardiac output and heart function, their use is associated with toxicity because of a narrow therapeutic index [50]. Tannins have anti-oxidative activities; due to these properties, they are anti-carcinogenic and anti-mutagenic. In addition, tannins have antimicrobial properties, accelerate blood clotting, reduce blood pressure, decrease serum lipid levels and modulate immune responses [51]. Reducing sugars have a regulatory role in plants, controlling their growth and development to provide resistance against diseases [52].

It is well known that combining several bioactive compounds result in a greater pharmacological response than using the single components [53]. With traditional medicines, isolating the desired phytochemicals and combining them can result in achieving the desired pharmacological response. More laboratory and clinical studies with hypoxis are required in this area of research.

Preclinical pharmacologic activities (Table 3)

Absorption and metabolism

After oral administration, hypoxoside is not absorbed and undergoes enzymatic hydrolysis. In the circulatory system, hypoxoside is converted to rooperol (Fig. 2) by β-glucosidase. Intragastric administration of hypoxoside in mice resulted in deconjugation by bacterial β-glucosidase to form rooperol in the colon. In mice, neither hypoxoside nor rooperol metabolites were detectable in the blood. There were only Phase II metabolites of sulphates and glucuronides present in the bile of mice, rats, and dogs [25]. However, in humans and baboons, these metabolites appear in the plasma at relatively high concentrations [26]. The end products of the hydrolysis were rooperol, dehydroxyrooperol and bis-dehydroxyrooperol [15]. The metabolic pathway of African Potato is illustrated in Fig. 3.

Table 3 Preclinical (in vivo) Pharmacologic Activities of Africa Potato in different formulations
Fig. 2
figure 2

Structures of hypoxoside and rooperol [10]

Fig. 3
figure 3

Metabolic Pathway of African Potato in Humans [11, 23]

The presence of rooperol was analyzed in faeces and urine in humans. After administration of 1 g of hypoxoside, rooperol was present in faeces at 6-h post-dosing. No rooperol was detected in urine after 24 h. Some of the rooperol was absorbed from the colon and some were eliminated in the faeces. The formation and absorption of rooperol was a zero-order saturable process [15].

Drug interaction studies

The effects on cytochrome P450 (CYP) - mediated metabolism of African Potato were studied in vitro using cell lines. The African Potato extracts demonstrated inhibitory effects on CYP3A4-, 3A5- and CYP19-mediated metabolism and high induction of P-glycoprotein (P-gp) as compared to ritonavir, the positive control [27]. Another study evaluated the effect of hypoxis on drug interactions in vitro using human liver microsomes. In methanol extracts, at least 95% inhibitory effects were observed for CYP1A2, 2C9, 3A4 and 2D6 compared to positive controls. Aqueous hypoxis extracts led to moderate CYP inhibition. The extracts of hypoxis indicated no significant inhibition of P-gp although the authors suggested some effect on P-gp was possible at higher concentrations than those used in the assays [28].

These in vitro results served as the foundation for in vivo interaction studies for African Potato. A study conducted in South Africa determined the effect of African Potato on efavirenz pharmacokinetics. Ten healthy volunteers participated in this single-dose, two-phase sequential study over 31 days [17]. Efavirenz is a non-nucleoside reverse transcriptase inhibitor (NNRTI) effective against HIV-1. It is the backbone of combination antiretroviral therapy (cART) in Africa and is mainly metabolized by CYP2B6 and to a lesser extent CYP3A4 [54]. For the South African study, the following parameters were used to determine interactions: AUC0–48, Cmax, Tmax, T1/2, and Kel. The results indicated that the 90% confidence intervals (CI) for Cmax and AUC0–48 were within the limits of 80–125% interval. Thus, the investigators concluded that the African Potato did not alter efavirenz pharmacokinetics. The investigators recommended that further research is needed to investigate African Potato and other antiretrovirals especially those that are P-gp substrates or CYP3A4 metabolites [17]. Although this study had a clear and concise methodology, the sample size calculations were not well explained, especially considering the intra-individual variability of the AUC and Cmax for efavirenz. In addition, single-dose studies do not consider induction that occurs during chronic dosing.

Another study investigated the effect of African Potato on the steady-state pharmacokinetics of ritonavir-boosted lopinavir (LPV/r). Lopinavir/ ritonavir is a potent HIV protease inhibitor combination that is used with other antiretrovirals for the treatment of HIV infection. Lopinavir (LPV) increases ritonavir (RTV) concentrations through inhibition of CYP3A4. LPV is metabolized primarily by hepatic and gastrointestinal CYP3A4. They hypothesized that since in vitro studies indicate that extracts of African Potato have a significant inhibitory effect on CYP3A4 this could lead to an increase in exposure, associated with an increased cholesterol/ diabetes risk. This study was an open-label, two-period; fixed sequence, crossover pharmacokinetic drug interaction study. Sixteen healthy, HIV-seronegative adult volunteers between 18 to 60 years were enrolled. The following parameters were used to determine interactions: AUC0–18, Cmax, Ctrough, Tmax, T1/2, CLF and Kel. Results indicated that steady-state plasma concentration-time profiles of LPV with and without African Potato were similar as reflected by the 90% confidence intervals that were within the 80–125% limit. The effect on ritonavir was not analyzed in this study. Total cholesterol and triglycerides were elevated but within limits during LPV/r treatment [18]. The investigators concluded that African Potato had no significant effect on the steady-state pharmacokinetics of LPV. This study was well designed although the results cannot be generalized to other populations. It would have been ideal to use participants from Africa, where African Potato use is prevalent. Clinical studies involving African Potato or its constituents are summarized in Table 4.

Table 4 Clinical Studies involving African Potato and/ its Constituents

Both the South African and USA studies were testing African Potato in healthy individuals. Literature reveals that African Potato is widely used for its immune-enhancing properties in HIV infected individuals [11]. Since African Potato has shown to be safe and well tolerated in healthy individuals, further research should focus on people living with HIV/AIDS. It would also be necessary to study the interactions of African Potato in HIV infected individuals taking other antiretroviral drugs.

Dosage recommendations

Traditionally, African Potato is cut into cubes or shredded and boiled in water for 20 min before the decoction is consumed orally. A survey conducted among traditional healers in South Africa was used to calculate the dose of African Potato. An average of about 20 g of freshly shredded African potato boiled in 250 mL of water was prescribed for daily consumption. African potato was mainly prescribed to boost immunity [37].

For the treatment of benign prostatic hyperplasia, African Potato dosed at 20 mg of β-sitosterol three times a day was found to be therapeutic [19]. According to literature, an oral dose of 15 mg/ kg/ day is reportedly therapeutic [18]; however, it is unknown whether this dose is effective for all the claims against African Potato. Other sources state that 2400 mg taken daily is therapeutic [15]. Standardized capsules are available online which contain from 300 to 350 mg hypoxis hemerocallidea. The doses for these formulations vary; some stating one capsule twice daily and some stating two tablets 3 times a day for the first 5 days, then one tablet 3 times a day [42, 43]. In South Africa, herbal formulations of African Potato are mainly used to enhance the immune system. The herbal formulations are available as capsules, tonics, creams and tinctures containing 300–500 mg hypoxis hemerocallidea or sterols/ sterolins [38]. With the many claims against the plant, it is unknown if this dose is a standard dose. Besides capsules, other formulations available include powders, face creams, night cream, nasal spray, soap, tissue oil, toner and exfoliator [44]. There is a knowledge gap in the therapeutic dosage for herbal medicines since most of the recommended doses are based on anecdotal information [11]. Furthermore, there is limited research in clinical trials using herbal medicines [55]. This is an area of research that could be explored further, even with African Potato.


African Potato rootstock (corm) is used to treat a wide variety of ailments. It is mainly used as an immunostimulant in people living with HIV/ AIDS. The active components include rooperol, which is an antioxidant and several phytosterols. The mechanisms of action for all the pharmacological actions are unknown. Some of the pharmacological actions were reported in older studies and there is a need for studies to substantiate the claims using current technology and with the application of systems pharmacology. African Potato is of intense commercial and scientific interest and more clinical trials should be performed to evaluate dosage regimens. The plant shows a good safety profile although there are no studies that have demonstrated safety in children, pregnant and lactating women. More research is required to substantiate the many claims that recommend the use of African Potato. There are important research gaps on the possible interactions with conventional drugs, especially those used in HIV/AIDS.

Availability of data and materials

All data generated and reviewed during this study was included in this manuscript and in the tables and figures.



Acquired immunodeficiency syndrome


African Potato


African Potato aqueous extract


Antiretroviral treatment


Area under the concentration-time curve within a dosing interval




β-sitosterol glucoside


Combination antiretroviral therapy


Apparent clearance

Cmax :

Maximum concentration following dose administration

Ctrough :

Plasma concentration at the end of the dosing interval


Cytochrome P450


Glomerular filtration rate


Gastrointestinal tract


Reduced glutathione

Kel :

Elimination rate constant


Human immunodeficiency virus




Ritonavir-boosted lopinavir






Non-nucleoside reverse transcriptase inhibitor




People living with HIV/ AIDS


Preferred Reporting Items for Systematic Reviews and Meta-Analyses


Red blood cells




Severe acute respiratory syndrome


Serum glutamate oxaloacetate transaminase


Serum glutamate pyruvate transaminase




Thiobarbituric acid reactive substance

Tmax :

Time to reach Cmax

T1/2 :



World Health Organization


  1. Zimudzi C. African potato (Hypoxis Spp): diversity and comparison of the phytochemical profiles and cytotoxicity evaluation of four Zimbabwean species. JAPS. 2014;4(4):79.

    Google Scholar 

  2. Herbal Medicine Market Size and Forecast, by product (tablets and capsules, powders, extracts), by indication (Digestive Disorders, Respiratory Disorders, Blood Disorders), and Trend Analysis, 2014–2024. Industry insights, Hexa Research Published: September 2017. https://wwwhexaresearchcom/research-report/global-herbal-medicine-market. Accessed 12 Sept 2018.

  3. Tilburt JC, Kaptchuk TJ. Herbal medicine research and global health: an ethical analysis. Bull World Health Organ. 2008;86:594–9.

    PubMed  PubMed Central  Google Scholar 

  4. World Health Organization. SARS: Clinical Trials on Treatment Using a Combination of Traditional Chinese Medicine and Western Medicine. 2004. Accessed 27 Sept 2018.

    Google Scholar 

  5. Centers for Disease Control and Prevention. 2004. Frequently asked questions about SARS. Accessed 27 September 2018.

    Google Scholar 

  6. Mudzviti T, Maponga CC, Khoza S, Ma Q, Morse GD. The impact of herbal drug use on adverse drug reaction profiles of patients on antiretroviral therapy in Zimbabwe. AIDS Res Treat. 2012;2012

  7. Bepe N, Madanhi N, Mudzviti T, Gavi S, Maponga CC, Morse GD. The impact of herbal remedies on adverse effects and quality of life in HIV-infected individuals on antiretroviral therapy. J Infect Dev Ctries. 2011;5(1):48.

    PubMed  PubMed Central  Google Scholar 

  8. Van Wyk BE. A review of commercially important African medicinal plants. J Ethnopharmacol. 2015;176:118–34

    PubMed  Google Scholar 

  9. Gail H, Tarryn B, Oluwaseyi A, Denver D, Oluchi M, Charlotte VK, de Joop J, Diana G. An ethnobotanical survey of medicinal plants used by traditional health practitioners to manage HIV and its related opportunistic infections in Mpoza, eastern Cape Province, South Africa. J Ethnopharmacol. 2015;171:109–15.

    PubMed  Google Scholar 

  10. Drewes SE, Elliot E, Khana F, Dhlaminic JTB, Gcumisad MSS. Hypoxis hemerocallidea—not merely a cure for benign prostate hyperplasia. J Ethnopharmacol. 2008;119(3):593–8.

    CAS  PubMed  Google Scholar 

  11. Mills E, Cooper C, Seely D, Kanfer I. African herbal medicines in the treatment of HIV: Hypoxis and Sutherlandia. An Overview of Evidence and Pharmacology. Nutr J. 2005;4:19.

    PubMed  PubMed Central  Google Scholar 

  12. Albrecht CF. Hypoxoside: a putative, non-toxic prodrug for the possible treatment of certain malignancies, HIV-infection and inflammatory conditions. In: Proc. 1st International IOCD-Symposium, Victoria Falls, Zimbabwe; 1996. p. 302–7.

    Google Scholar 

  13. Viallard JF, Blanco P, André M, Etienne G, Liferman F, Neau D, Vidal E, Moreau JF, Pellegrin JL. CD8+HLA-DR+ T lymphocytes are increased in common variable immunodeficiency patients with impaired memory B-cell differentiation. Clin Immunol. 2006;119(1):51–8 Epub 2006 Jan 18. PubMed PMID: 16413828.

    CAS  PubMed  Google Scholar 

  14. Moher D, Liberati A, Tetzlaff J, Altman DG, PRISMA Group. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. J Clin Epidemiol. 2009;62(10):1006–12.

    PubMed  Google Scholar 

  15. Albrecht CF, Kruger PB, Smit BJ, Freestone M, Gouws L, Miller R, van Jaarsveld PP. The pharmacokinetic behaviour of hypoxoside taken orally by patients with lung cancer in a phase I trial. S Afr Med J. 1995;85(9):861–5.

    CAS  PubMed  Google Scholar 

  16. Donald PR, Lamprecht JH, Freestone M, Albrecht CF, Bouic PJ, Kotze D, Van Jaarsveld PP. A randomised placebo controlled trial of the efficacy of beta-sitosterol and its glucoside as adjuvants in the treatment of pulmonary tuberculosis. Int J Tuberc Lung Dis. 1997;1:518–22.

    CAS  PubMed  Google Scholar 

  17. Mogatle S, Skinner M, Mills E, Kanfer I. Effect of African potato (Hypoxis hemerocallidea) on the pharmacokinetics of efavirenz. S Afr Med J. 2008;98(12):945–9.

    CAS  PubMed  Google Scholar 

  18. Gwaza L, Aweeka F, Greenblatt R, Lizak P, Huang L, Guglielmo BJ. Co-administration of a commonly used Zimbabwean herbal treatment (African potato) does not alter the pharmacokinetics of lopinavir/ritonavir. Int J Infect Dis. 2013;17(10):e857–61.

    CAS  PubMed  PubMed Central  Google Scholar 

  19. Berges RR, Windeler J, Trampisch HJ, Senge T. Randomised, placebo-controlled, double-blind clinical trial of β-sitosterol in patients with benign prostatic hyperplasia. Lancet. 1995;345(8964):1529–32.

    CAS  PubMed  Google Scholar 

  20. Bouic PJ, Clark A, Brittle W, Lamprecht JH, Freestone M, Liebenberg RW. Plant sterol/sterolin supplement use in a cohort of south African HIV-infected patients – effects on immunological and virological surrogate markers. S Afr Med J. 2001;91:848–50.

    CAS  PubMed  Google Scholar 

  21. Boukes GJ, Daniels BB, Albrecht CF, van de Venter M. Cell survival or apoptosis: rooperol’s role as anticancer agent. Oncol Res. 2010;18:365–76.

    CAS  PubMed  Google Scholar 

  22. Awad AB, Gan Y, Fink CS. Effect of b-sitosterol, a plant sterol, on growth, protein phospholipase 2A and phospholipid D in LNCaP cells. Nutr Cancer. 2000;36:74–8.

    CAS  PubMed  Google Scholar 

  23. Bouic PJ, Etsebeth S, Liebenberg RW, Albrecht CF, Pegel K, Van Jaarsveld PP. Beta-sitosterol and beta-sitosterol glucoside stimulate human peripheral blood lymphocyte proliferation: implications for their use as an immunomodulatory vitamin combination. Int J Immunopharmacol. 1996;18(12):693–700.

    CAS  PubMed  Google Scholar 

  24. Lamprecht JH, Freestone M, Bouic PJD. A comparison of the survival benefit provided by putative immune modulators in the FIV (feline immunodeficiency virus) infected laboratory cat model. In: Proceedings of the 13th international AIDS conference; Durban. Bologna: Monduzzi Editore; 2000. p. 21–4.

    Google Scholar 

  25. Albrecht CF, Theron EJ, Kruger PB. Morphological characterisation of the cell-growth inhibitory activity of rooperol and pharmacokinetic aspects of hypoxoside as an oral prodrug for cancer therapy. S Afr Med J. 1995;85:853–60.

    CAS  PubMed  Google Scholar 

  26. Kruger PS, de V Albrecht CF, Uebenberg RW, Van Jaarsveld PP. Studies on hypoxoside and rooperol analogues from Hypoxis rooperi and H. latifolia and their biotransformation in man by using high-performance liquid chromatography with in-line sorption enrichment and diode array detection. J Chromatogr. 1994;662:71–8.

    CAS  Google Scholar 

  27. Nair VDP, Foster BC, Arnason JT, Mills EJ, Kanfer I. In vitro evaluation of human cytochrome P450 and P-glycoprotein-mediated metabolism of some phytochemicals in extracts and formulations of African potato. Phytomedicine. 2007;14(7):498–507.

    CAS  PubMed  Google Scholar 

  28. Gwaza L, Wolfe AR, Benet LZ, Guglielmo BJ, Chagwedera TE, Maponga CC, Masimirembwa CM. In vitro inhibitory effects of Hypoxis obtusa and Dicoma anomala on cyp450 enzymes and p-glycoprotein. Afr J Pharm Pharmacol. 2009;3(11):539–46.

    Google Scholar 

  29. Musabayane CT, Xozwa K, Ojewole KA. Effects of Hypoxis hemerocallidea (Fisch. & C.a. Mey.) [Hypoxidaceae] corm (African potato) aqueous extract on renal electrolyte and fluid handling in the rat. Ren Fail. 2005;27:763–70.

    CAS  PubMed  Google Scholar 

  30. Ojewole JA. Anticonvulsant activity of Hypoxis hemerocallidea Fisch. & C. A. Mey. (Hypoxidaceae) corm ('African potato') aqueous extract in mice. Phytother Res. 2008;22(1):91–6.

    CAS  PubMed  Google Scholar 

  31. Nyinawumuntu A, Awe EO, Ojewole JA. Uterolytic effect of Hypoxis hemerocallidea Fisch. & C.a. Mey. (Hypoxidaceae) corm [‘African potato’] aqueous extract. J Smooth Muscle Res. 2008;44(5):167–76.

    PubMed  Google Scholar 

  32. Erlwanger KH, Cooper RG. The effects of orally administered crude alcohol and aqueous extracts of African potato (Hypoxis hemerocallidea) corm on the morphometry of viscera of suckling rats. Food Chem Toxicol. 2008;46(1):136–9.

    CAS  PubMed  Google Scholar 

  33. Ojewole JA, Awe EO, Nyinawumuntu A. Antidiarrhoeal activity of Hypoxis hemerocallidea Fisch. & C. A. Mey. (Hypoxidaceae) corm ('African potato') aqueous extract in rodents. Phytother Res. 2009;23(7):965–71.

    PubMed  Google Scholar 

  34. Liu Z, Wilson-Welder JH, Hostetter JM, Jergens AE, Wannemuehler MJ. Prophylactic treatment with Hypoxis hemerocallidea corm (African potato) methanolic extract ameliorates Brachyspira hyodysenteriae-induced murine typhlocolitis. Exp Biol Med (Maywood). 2010;235(2):222–30.

    CAS  Google Scholar 

  35. Chaturvedi P, Mwape MP. Effect of African potato (Hypoxis hemerocallidea) extract on oxidative stress induced by chloroquine in albino rats. Afr J Food Agric Nutr Dev. 2011;11(1):4476–89.

  36. Oguntibeju OO, Meyer S, Aboua YG, Goboza M. Hypoxis hemerocallidea significantly reduced hyperglycaemia and hyperglycaemic-induced oxidative stress in the liver and kidney tissues of streptozotocin-induced diabetic male Wistar rats. Evid Based Complement Alternat Med. 2016;2016:1–10.

  37. Nair VDP, Kanfer I. High-performance liquid chromatographic method for the quantitative determination of Hypoxoside in African potato (Hypoxis hemerocallidea) and in commercial products containing the plant material and/or its extracts. J Agric Food Chem. 2006;54:2816–21.

    CAS  PubMed  Google Scholar 

  38. Ncube B, Ndhlala AR, Okem A, Van Staden J. Hypoxis (Hypoxidaceae) in African traditional medicine. J Ethnopharmacol. 2013;150(3):818–27.

    PubMed  Google Scholar 

  39. Bouic PJD. The role of phytosterols and phytosterolins in immune modulation: a review of the past 10 years. Curr Opin Clin Nutr Metab Care. 2001;4:471–5.

    CAS  PubMed  Google Scholar 

  40. Ling WH, Jones PJH. Dietary phytosterols: a review of metabolism, benefits and side effects. Life Sci. 1995;57:195–206.

    CAS  PubMed  Google Scholar 

  41. Saeidnia S, Manayi A, Gohari AR, Abdollahi M. The story of beta-sitosterol-a review. Eur J Med Plants. 2014;4(5):590.

    CAS  Google Scholar 

  42. Inkomfe Capsules (African Potato). Natures Health. Accessed 17 Oct 2018.

  43. African Potato Capsule. Green Herbs & Nutrition’s Stores. Accessed 17 Oct 2018.

  44. Colour in the cold. Puer Orijins Catalogue and specials. Accessed 17 Oct 2018.

  45. Wen H, Jung H, Li X. Drug delivery approaches in addressing clinical pharmacology-related issues: opportunities and challenges. AAPS J. 2015;17(6):1327–40.

    CAS  PubMed  PubMed Central  Google Scholar 

  46. Grinsztejn B, Hosseinipour MC, Ribaudo HJ, Swindells S, Eron J, Chen YQ, HPTN 052-ACTG Study Team. Effects of early versus delayed initiation of antiretroviral treatment on clinical outcomes of HIV-1 infection: results from the phase 3 HPTN 052 randomised controlled trial. Lancet Infect Dis. 2014;14(4):281–90

    CAS  PubMed  PubMed Central  Google Scholar 

  47. Usman H, Haruna AK, Akpulu IN, Ilyas M, Ahmadu AA, Musa YM. Phytochemical and antimicrobial screenings of the leaf extracts of Celtis integrifolia. Lam J Trop Biosci. 2005;5(2):72–6.

    Google Scholar 

  48. Sermakkani M, Thangapandian V. Phytochemical Screening for Active Compounds in Pedalium murex L. Recent Res Sci Technol. 2010;2(1):110–14.

  49. Ali N, Shah SW, Shah I, Ahmed G, Ghias M, Khan I. Cytotoxic and anthelmintic potential of crude saponins isolated from Achillea Wilhelmsii C. Koch and Teucrium Stocksianum boiss. BMC Complement Altern Med. 2011;11:106.

    CAS  PubMed  PubMed Central  Google Scholar 

  50. Schneider G, Wolfling J. Synthetic cardenolides and related compounds. Curr Org Chem. 2004;8:1381–403.

    CAS  Google Scholar 

  51. Serrano J, Puupponen-Pimiä R, Dauer A, Aura AM, Saura-Calixto F. Tannins: current knowledge of food sources, intake, bioavailability and biological effects. Mol Nutr Food Res. 2009;53(S2):S310–29.

    PubMed  Google Scholar 

  52. Morkunas I, Ratajczak L. The role of sugar signaling in plant defense responses against fungal pathogens. Acta Physiol Plant. 2014;36(7):1607–19.

    CAS  Google Scholar 

  53. Pallarès V, Calay D, Cedó L, Castell-Auví A, Raes M, Pinent M, Ardévol A, Arola L, Blay M. Additive, antagonistic, and synergistic effects of procyanidins and polyunsaturated fatty acids over inflammation in RAW 264.7 macrophages activated by lipopolysaccharide. Nutrition. 2012;28(4):447–57.

    PubMed  Google Scholar 

  54. Ward BA, Gorski JC, Jones DR, Hall SD, Flockhart DA, Desta Z. The cytochrome P450 2B6 (CYP2B6) is the main catalyst of efavirenz primary and secondary metabolism: implication for HIV/AIDS therapy and utility of efavirenz as a substrate marker of CYP2B6 catalytic activity. J Pharmacol Exp Ther. 2003;306:287–300.

    CAS  PubMed  Google Scholar 

  55. Monera-Penduka TG, Nhachi C, Maponga C, Morse G. A Research Strategy for the Development of Clinical Evidence for Traditional Herbal Medicine. Accessed 17 Oct 2018.

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Celia M. J Matyanga had access to resources for the systematic review and this was supported by Grant Numbers D43TW010313, D43TW007991 and D43TW007991 01A2S1 from the Fogarty International Center. During the peer-review process, Celia M. J Matyanga had access to resources as supported by the L’Oréal-UNESCO For Women in Science Sub-Saharan Africa 2019 Young Talents Award. The content is solely the responsibility of the authors and does not necessarily represent the official views of the Fogarty International Center or the National Institutes of Health or the L’Oréal-UNESCO For Women in Science Programme.

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CM conceptualized the research and GM, MG and CN approved the topic. CM conducted the literature review and all authors analysed the results of the review. All authors participated in giving feedback on the manuscript. All authors have read and approved the final manuscript.

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Correspondence to Celia M. J. Matyanga.

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Matyanga, C.M.J., Morse, G.D., Gundidza, M. et al. African potato (Hypoxis hemerocallidea): a systematic review of its chemistry, pharmacology and ethno medicinal properties. BMC Complement Med Ther 20, 182 (2020).

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