Nicholas J. Sadgrove

Royal Botanic Gardens, Kew · Commercial Phytochemistry Unit

The ten countries that make up southern Africa are collectively a hot-spot of medicinal plant knowledge, with a unique preference for the utilization of bark over leaves from possibly hundreds of species. The most popular 86 medicinal bark species were identified in an earlier survey of various muthi markets around Johannesburg, and are listed in t...

Phytochemical analysis of the twigs and leaves of Croton kinondoensis, endemic to Kenya, yielded known compounds 3-(3',4'-dimethoxyphenyl)-prop-1-ene (1), 3-(3',4'-dimethoxyphenyl)-propenal (2), lupeol (3) and ent-trachyloban-19-oic acid (4), and a tentatively new ent-clerodane diterpenoid, crotokinondoenolide (5). ent-Trachy-loban-19-oic acid (4)...

Thixotropic gels are the preferred choice in the collection of platelet-rich plasma as an easy solution to operator variability. One often unnoticed shortcoming is the entrapment of platelets in the gel layer's uppermost surface. We provide instructions to optimize platelet yield, ie, agitation to re-suspend platelets, setting the optimal G-force a...

Piper aduncum L., a Brazilian medicinal plant, is known for its bioactive properties, including repellent and insecticidal effects. This study investigated the insecticidal potential of essential oils (EOs) from P. aduncum, collected during the dry and rainy seasons, against fleas (Ctenocephalides felis felis Bouché, 1835) in egg and adult stages....

The seeds of Khaya anthotheca, (Welv.) yielded two undescribed limonoids, 1α,7α-diacetoxyhavanensin-16-one (1) and 3α,7α-diacetoxyhavanensin-16-one (2), as well as three known limonoids, khayanthone (3), 3,7-di-O-acetyl-14,15-deoxyhavanensin (4) and 1,7-di-O-acetyl-14,15-deoxyhavanensin (5). The antiplasmodial activities of the CH 2 Cl 2 extract an...

To make the distinction against pharmaceuticals, natural product medicines are more accurately denoted as nutritional therapies. In the context of topical therapies targeting dermatological conditions, nutritional therapy may explain the mechanism of ethnocosmetic plants used in hair treatment and care. Inspired by emerging theories of a connection...

Hemp (Cannabis sativa L.) is a widely researched industrial crop with a variety of applications in the pharmaceutical, nutraceutical, food, cosmetic, textile, and materials industries. Although many of these applications are related to its chemical composition, the chemical diversity of the hemp metabolome has not been explored in detail and new me...

In this current review, research spanning the last decade (such as transcriptomic studies, phenotypic observations, and confirmed comorbidities) has been synthesized into an updated etiology of hair loss and applied to the new cosmeceutical paradigm of hair rejuvenation. The major etiological components in scalps with hair loss are denoted as the ‘...

Pattern-type hair loss is a highly prevalent condition affecting the majority of men and women at some point in their lifetime. Although genetics and androgens are instrumental in the pathogenesis of this type of hair loss, it is increasingly recognized that inflammation, stress, and environmental factors play a central role. The few and widely use...

Non-communicable diseases (NCDs) are becoming more common in remote regions, whereas previously they were more common in middle-class to wealthy societies. The rising prevalence and severity of NCDs has increased the demand for medical innovation in this space. In this regard, knowledge of traditional medicines used in the treatment of NCDs, by peo...

The genus Senecio is one of the largest in Asteraceae. There are thousands of species across the globe, either confirmed or awaiting taxonomic delimitation. While the species are best known for the toxic pyrrolizidine alkaloids that contaminate honeys (as bees select pollen from the species) and teas via lateral transfer and accumulation from adjac...

There are almost 1000 species of Acacia sensu stricto in Australia, while the 44 species and 4 subspecies in southern Africa were taxonomically revised in the year 2011 to Senegalia and Vachel-lia. There are rumors of a chemical similarity between the Australian Acacia and their southern African sister genera. Chemical analysis has unequivocally de...

The rising burden of cardiovascular disease in South Africa gives impetus to managerial changes, particularly to the available foods in the market. Since there are many economically disadvantaged groups in urban societies who are at the forefront of the CVD burden, initiatives to make healthier foods available should focus on affordability in conju...

The study of plant secondary metabolites, now designated as specialized metabolites, is motivated by multiple scientific objectives, ranging from bioprospecting for bioactive molecules to answering ecological and evolutionary questions. This paper provides a constructive commentary on chemosystematics, or chemotaxonomy, and chemophenetic analyses t...

Cardiovascular disease (CVD) is a major cause of illness and death globally. Its incidence has been closely linked to diet. This chapter reviews the complex nature of CVD and its comorbidities. It then assesses the current state of research on the protective and therapeutic effects of a range of plant phytochemicals in relation to CVD. It also addr...

This study tested the hypothesis that “clonal chemical heritability is a crucial factor for the conservation of chemical uniformity of Piper essential oils in controlled monoclonal cultivation”. We asexually propagated first and second-generation clones of two medicinal and aromatic species, Piper gaudichaudianum Kunth and Piper mollicomum Kunth (P...

The stems and leaves of robusta coffee, Coffea canephora Pierre ex A. Froehner, one of the traded Coffea species, yielded caffeine (1), lupeol (2), ursolic acid (3), 3β-acetyl oleanolic acid (4), friedelin (5), asperphernamate (6), squalene (7), stigmasterol (8), stigmasterol�3-O-β-D-glucopyranoside (9) and chlorophyll a (10). The structures of the...

Reported herein is an anti-HIV monochlorinated compound, 1β-acetoxy-3β-chloro-5α,6α-dihydroxycrotocascarin L (1), of the rare crotofolane diterpenoid class. Compound 1, a suspected artifact of extraction, along with the previously undescribed 11β-acetoxycrotocascarin L (2) and a known compound, crotocascarin K (3), were isolated from the bark of Cr...

Grape seeds are a rich source of flavan-3-ol monomers, oligomers, and polymers. The diverse profile of compounds includes mainly B-type procyanidins (especially C4!C8 linked molecules) and the key monomers, catechin, and epicatechin that are positively implicated in the ‘French Paradox’. Today grape seed nutraceuticals have become a multi-million-d...

The current text provides a comprehensive introduction to essential oils, their biosynthesis, naming, analysis, and chemistry. Importantly, this text quickly brings the reader up to a level of competence in the authentication of essential oils and their components. It gives detailed descriptions of enantiomers and other forms of stereoisomers relev...

In our continued study on the anti-HIV activity of compounds present in CareVid TM , we report the HIV-1 integrase ((HIV-1 IN) inhibitory effects of pellitorine (1), oleuropein (2), magnoflor-ine (3), crotepoxide (4), ent-kaurane-16β,17-diol (5), crotocorylifuran (6), lupeol (7), betulin (8), and ellagic acid (9) in an in vitro enzyme assay, and in...

In this comprehensive commentary, Australian essential oils and their components are listed and discussed in the context of their value to industry and aesthetics. The historic and cultural significance of endemic essential oils is explained. Several promising candidates are identified that have commercial potential and will enter the marketplace i...

The discovery of antibiotics more than 80 years ago has led to considerable improvements in human and animal health. Although antibiotic resistance in environmental bacteria is ancient, resistance in human pathogens is thought to be a modern phenomenon that is driven by the clinical use of antibiotics1. Here we show that particular lineages of meth...

A chemical investigation of the leaves of Tabernaemontana inconspicua Stapf. led to the isolation of a new phenylpropanol derivative, namely irisdichototin G (1), together with nine known compounds, including one polyol derivative, dambonitol (2); three alkaloids, 10-hydroxycoronaridine (3), voacristine (4) and vobasine (5); two triterpenes lupeol...

When it comes to painful bladder and kidney stones, you are not alone! Records of nuisance stones can be found at all points in time, in all geographies, races, and civilizations. Descriptions of bladder and kidney stones are written in the oldest records available, and probably date back further, to a time before recorded history. The only thing...

Fruit from A. hippocastanum L. are used commercially for chronic venous insufficiency (CVI). The isomeric mixture of pentacyclic triterpenoid saponins (beta-aescin) exert anti-inflammatory effects. Hence, research has focused on beta-aescin, yet the diversity, accumulation, and bioactivity of organ-specific secondary metabolites represent missed ph...

The cylindrical conflorescences of the Banksia spinulosa Sm complex have several different colour types, i.e., black, red, maroon, lemon, and yellow. It is unknown if colour variation is due to extrinsic factors, importantly soil pH. Recent morphological observations have indicated that style colour are not contiguous, so follow-up chemical and soi...

The diaspores of Lepidosperma Labill. (Cyperaceae) have thickened perianth members persistent at the base of the fruit, which are generally assumed to form a unique type of elaiosome but this assumption has not been tested rigorously. We tested whether the perianth provides a lipid-rich food reward and improves diaspore removal by ants in three spe...

This commentary critically examines the modern paradigm of natural volatiles in ‘medical aromatherapy’, first by explaining the semantics of natural volatiles in health, then by addressing chemophenetic challenges to authenticity or reproducibility, and finally by elaborating on pharmacokinetic and pharmacodynamic processes in food, therapy, and di...

The aromatic species Piper gaudichaudianum Kunth (Piperaceae) is widely used in Brazil for medicinal and ritualistic applications. In the current study, chemophenetic patterns were realized across season and circadian rhythm based on the chemical profile of essential oils (EOs) from leaves. Hydrodistilled essential oils were analyzed by GC-MS and G...

CareVid is a multi-herbal product used in southwest Kenya as an immune booster and health tonic and has been anecdotally described as improving the condition of HIV-positive patients. The product is made up of roots, barks and whole plant of 14 African medicinal plants: Acacia nilotica (L.) Willd. ex Delile (currently, Vachelia nilotica (L.) P.J.H...

Meliaceae are widely distributed across the world in tropical or subtropical climates and are of considerable ethnobotanical importance as sources of traditional medicine and cos- metics. This comprehensive review summarizes the ethnobotanical uses and chemistry of 12 South African species, belonging to six genera: Ekebergia, Nymania, Entandrophrag...

Scientific studies of Aloe vera have tentatively explained therapeutic claims from a mechanistic perspective. Furthermore, in vitro outcomes demonstrate that the breakage of acemannan chains into smaller fragments enhances biological effects. These fragments can intravenously boost vaccine efficacy or entrain the immune system to attack cancer cell...

Vitex doniana Sweet is an African medicinal species that is prescribed as an aqueous bark extract to be applied topically or orally to achieve anti-infective outcomes. In select regions it is also taken orally as an antimalarial agent. The aim of the current study was to explore the biological properties of V. doniana and isolated compounds in the...

Indigenous trade of medicinal plants in South Africa is a multi-million-rand industry and is still highly relevant in terms of primary health care. The purpose of this study was to identify today's most traded medicinal barks, traditionally and contemporaneously used for dermatological, gastrointestinal, and respiratory tract infections; then, to i...

One of the side‐effects of oral anti‐aging retinoids is increased hair shedding. Retinoids promote the expression of TGF‐β2 from fibroblasts, which stimulate collagen expression but silences keratinocytes. Since keratinocytes normally influence differentiation of dermal papilla cells at the base of the hair follicle, retinoids feasibly inhibit hair...

Background The success of 5α-reductase inhibitors in the 1990s vindicated the role of androgens and cast doubt on the role of diet in androgenetic alopecia (AGA). However, poor glucose control and high cholesterol are now recognised as comorbidities, which are salient characters of the ‘western diet’. Scope and approach In glucose potentiated hair...

Background Cosmetic treatments that inspire one's appearance to resemble their younger portrait often utilize ingredients that confer acute effects, particularly hydration by creating hydrophobic barriers or transient elevation of barrier water content. But superior therapies successfully promote morphogenesis of the dermal-epidermal junction, insp...

Australia’s endemic desert shrubs are commonly aromatic, with chemically diverse terpenes and phenylpropanoids in their headspace profiles. Species from the genus Eremophila (Scrophulariaceae ex. Myoporaceae) are the most common, with 215 recognised taxa and many more that have not yet been described, widely spread across the arid parts of the Aust...

Colorectal cancer (CRC) represents the third leading cause of death among cancer patients below the age of 50, necessitating improved treatment and prevention initiatives. A crude methanol extract from the wood pulp of Artocarpus heterophyllus was found to be the most bioactive among multiple others, and an enriched extract containing 84% ( w / v )...

An aromatic alkaloid-rich ‘absolute’ extract from Vepris gossweileri inhibited Saccharomyces cerevisiae at 62.5 μg.mL−1 and Bacillus subtilis at 500 μg.mL−1. A loss of activity upon fractionation indicated possible synergistic effects. Three new acridones, gossweicridone A (3), B (4) and C (5) and known compounds from the extract were inactive. Com...

We describe two new terpenoids, 3′',5′'-dihydroxycinnamoyl-3β,28,30-dihydroxylup-20(29)-ene (1) and 6S,9S-dihydroxycasbe-3E,7E,11E-trien-5,10-dione (2) and ten known asperglaucide, aridanin, isoscopoletin, maslinic acid, ursolic acid, oleanolic acid, lupeol, sitosterol, stigmasterol and stigmasterol-glucoside from a West African, Guineo-Congolian m...

This study analyzed the antimicrobial effects of compounds present in the roots and leaves of Citrus x limon (L.) Osbeck to help understand how this plant (1) ecologically modulates microbial defense in the rhizosphere and (2) protects against food-borne bacterial pathogens. Antimicrobial effects of C. limon collected from a farm in Foumban in Came...

With the increasing demand for natural products by the consumer in the marketplace it is necessary to see a proportional increase in behind-the-scenes science to ensure that the ideology of safety and honesty, that is justifiably expected by the wider public, is adequately satisfied. It is of essence to have a fair yet firm governance of nutraceuti...

The Meliaceae are a flowering plant family of mostly trees and shrubs (with few herbaceous plants and mangroves) in the order Sapindales. Meliaceae comprise 50 genera and over 1400 species, including the largest tree in Africa (Entandrophragma excelsum Sprague), which is about 81.5 m high on Mt Kilimanjaro. They are widely distributed worldwide, oc...

The highly aromatic Australian mint bushes from the genus Prostanthera Labill. produce a high yield of essential oil on hydrodistillation. Together with its rich history, horticultural potential, iconic flowers, and aromatic leaves, it achieves high ornamental and culinary value. Species in the genus express highly diverse and chemically unique ess...

Smallanthus sonchifolius (yacon) is an edible tuberous Andean shrub that has been included in the diet of indigenous people since before recorded history. The nutraceutical and medicinal properties of yacon are widely recognized, especially for the improvement of hyperglycemic disorders. However, the chemical diversity of the main bioactive series...

The modern paradigm of aromatherapy is based on in vitro assays of pure volatile organic compounds (as an essential oil), with activity at non-clinically significant concentrations. Yet traditional use of aromatic species did not involve pure essential oils because hydrodistillation was only invented in relatively recent times (estimated 1200 AD)....

The aromatic pink-flowered Phebalium complex is comprised by P. nottii Maiden & Betche, P. speciosum I. Telford and the very similar but mostly white-flowered P. woombye (F.M.Bailey) Domin. Phebalium nottii, as currently circumscribed, includes several geographically disjunct populations that have been segregated at the N.C.W. Beadle Herbarium as p...

Prostanthera lasianthos (Lamiaceae) is commonly referred to as the 'Victorian Christmas Bush', a name that derives from the floral display it gives in the Christmas period. However, botanists recognise P. lasianthos as a heterogeneous species aggregate that includes several putative new species that are confined to disjunct locations. Recently one...

Prenylated (iso)flavonoids, -flavans and pterocarpans from taxa in Erythrina are repeatedly flagged as potent antimicrobial compounds. In the current study, bark from E. lysistemon was extracted and seven isoflavone derivatives were purified: erybraedin A (1), phaseollidin (2), abyssinone V-4’ methyl ether (3), eryzerin C (4), alpumisoflavone (5),...

The symptom “fever” is generally not itself a terminal condition. However, it does occur with common mild to severe ailments afflicting the world population. Several allopathic medicines are available to attenuate fever by targeting the pathogen or the symptom itself. However, many people in marginal civilizations are obligated to use locally grown...

In spite of the evidence for antimicrobial and acaricidal effects in ethnobotanical reports of Callitris and Widdringtonia, the diterpene acids from Widdringtonia have never been described and no comparison to the Australian clade sister genus Callitris has been made. The critically endangered South African Clanwilliam cedar, Widdringtonia wallichi...

Pentzia punctata Harv. (Asteraceae) is one of 27 species occurring in southern and North Africa. It is a Cape species that is used in traditional medicine to treat stomach ailments and respiratory complaints. Pentzia punctata is locally known in the Cape as bergwildeals and is considered to be a more potent medicine than the well-known wildeals (Ar...

The new era of multidrug resistance of pathogens against frontline antibiotics has compromised the immense therapeutic gains of the ‘golden age,’ stimulating a resurgence in antimicrobial research focused on antimicrobial and immunomodulatory components of botanical, fungal or microbial origin. While much valuable information has been amassed on th...

The chemistry of essential oils from the leaves of three African species of Croton (C. gratissimus, C. pseudopulchellus and C. sylvaticus) is comprehensively characterised. Two new volatile diterpenes were isolated from C. gratissimus and the structures assigned using 1D and 2D NMR. One is a furanyl-halimane methyl ester (1) assigned as 12-β-furany...

We report the catalytic ozonation as a viable tool in the oxidative degradation of cresol isomers. SiO2-supported metal catalysts with 2.5 and 7.5 wt.% (Ni, Fe, Mn, V) were employed in this ozone initiated oxidation reactions. All catalysts were characterized using various analytical techniques such as XRD, FT-IR, SEM-EDX, TEM, ICP-OES, and BET-sur...

Leysera gnaphalodes (L.) L. (viz., Leyssera gnaphalioides L.) is an aromatic, medicinal Cape herbal tea endemic to southern Africa. The plant is known by many different vernacular names, most relating to its use as tea: geelblommetjiestee, duinetee(bossie), skilpadtee(bossie), teringtee(bossie), hongertee and geeltee. According to historical litera...

Phebalium graniticola I.Telford & J.J.Bruhl, P. stellatum I.Telford & J.J.Bruhl and P. sylvaticum I.Telford & J.J.Bruhl are segregated as new species from Phebalium squamulosum Vent. subsp. squamulosum. Essential oil data support the recognition of these species as distinct. Distributions of the new species are mapped, and their habitat and conserv...

A comprehensive review of indigenous knowledge about a traditional Cape, San and Khoi food item called anise root or anyswortel (genus Annesorhiza) is presented. The first accurate record was by Thunberg in 1772 at the Berg River near Vlermuisdrift (now Bridgetown) in the Western Cape and applied to A. grandiflora. Four species have recorded food u...

A step-economic biomimetic synthesis of mitchellenes B–H found in Eremophila sturtii has been achieved. Starting from the putative muurolane biological precursor, a redox isomerization of the allylic alcohol gave an epimeric mixture of aldehydes, which could be used as a handle for cyclization onto the C6 position using Bu3SnH mediated radical cycl...

Warburgia salutaris is one of the most popular trees used in traditional medicine throughout tropical southeast Africa, because of its ability to treat a wide variety of illnesses caused by fungi, bacteria, viruses and insects. The aim of the study was to test the antimicrobial activity of W. salutaris and its isolated compounds against selected sk...

Elaeodendron transvaalense stem bark is widely used in southern African traditional medicine, mainly for gastrointestinal tract disorders and skin ailments. The aim of the study was to investigate the possible scientific rationale for the popularity and ethnobotanical uses of E.transvaalense. To achieve this aim, target pathogens related to infecti...

Abstract Ethnopharmacological relevance Research in the past half a century has gradually sketched the biological mechanism leading to androgenetic alopecia (AGA). Until recently the aetiological paradigm has been too limited to enable intelligent commentary on the use of folk remedies to treat or reduce the expression of this condition. However,...

Pentzia incana is one of the most important of all natural pasture plants in the dry interior (Karoo) region of South Africa. This highly aromatic shrub is thought to be responsible for the distinctive flavour of Karoo lamb (a registered geographical indication), yet the essential oil is here characterised for the first time. Leafy twigs are tradit...

The 70 popular medicinal barks from different plant species were purchased from the South African traditional medicine markets. Ethnobotanical information, including traditional uses, method of preparation, dosage and mode of administration were recorded from the ‘muthi’ market traders. The bark samples from 32 plant species with 68 (methanol and d...

Eremophila sturtii and E. mitchellii are found in the arid and temperate regions of Australia and, because of their similar appearances, are often confused. Previous phytochemical investigations have described mitchellene sesquiterpenes (1–5) reported from E. mitchellii but are here demonstrated to be from E. sturtii. A previous study that describe...

The aromatic culinary herb Pelargonium crispum is used as a condiment across the world to confer a lemony aroma to food. The phytochemistry of one cultivar of unknown origin has been tentatively described in earlier studies, with only the dominant volatile components assigned as neral and geranial and with chrysin as the major flavone. In the curre...

Eremophila sturtii and Eremophila mitchellii are found in the arid and temperate regions of Australia and due to similar appearances are often confused. Previous phytochemical investigations have described a series of tetracyclic sesquiterpenes named the mitchellenes that were reported to derive from E. mitchellii but are demonstrated conclusively...

The stem bark sample of Erythrina lysistemon was collected from the Faraday muthi market in Johannesburg. The ethnobotanical uses of the stem bark mentioned from this market are an infusion of the bark taken orally for stomach ulcers, stomach ache, internal and external wound healing. The chemistry of the stem bark was acquired through the use of c...

Over the last few years, in the course of natural product isolation, our research has enjoyed a ‘cross-pollination’ of chemistry, taxonomic botany, microbiology, pharmacology and ethnobotany. This search for interesting new metabolites from Australian members of Cupressaceae, Lamiaceae, Pittosporaceae, Rutaceae and Scrophulariaceae has generated a...