Melanie-Jayne R Howes

Royal Botanic Gardens, Kew · Natural Capital and Plant Health

Plants are a rich source of bioactive compounds and a number of plant-derived antiplasmodial compounds have been developed into pharmaceutical drugs for the prevention and treatment of malaria, a major public health challenge. However, identifying plants with antiplasmodial potential can be time-consuming and costly. One approach for selecting plan...

We present a genome assembly from an individual Scutellaria galericulata (the marsh skullcap; Streptophyta; Magnoliopsida; Lamiales; Lamiaceae). The genome sequence is 328 megabases in span. Most of the assembly is scaffolded into 15 chromosomal pseudomolecules. The mitochondrial and plastid genomes have also been assembled and have lengths of 326....

Ethnopharmacological relevance: Neuronal death is a central process in neurodegenerative diseases and represents a therapeutic challenge for their prevention and treatment. Scutellaria incarnata Vent. roots are used traditionally in Colombia for central nervous system conditions including those affecting cognitive functions, but their chemistry an...

Medicinal plants are an excellent source of structurally diverse, bio-active compounds with potential in the fight against cancer. One of the most promising is Scutellaria barbata, prescribed traditionally for the treatment of cancers. Scutebarbatine A is the major diterpenoid, produced in specialized large, peltate trichomes on leaves of S. barbat...

Drug discovery from natural sources is going through a renaissance, having spent many decades in the shadow of synthetic molecule drug discovery, despite the fact that natural product-derived compounds occupy a much greater chemical space than those created through synthetic chemistry methods. With this new era comes new possibilities, not least th...

With more than two billion people suffering from malnutrition and diets homogenizing globally, it is vital to identify and conserve nutrient-rich species that may contribute to improving food security and diversifying diets. Of the approximately 390,000 vascular plant species known to science, thousands have been reported to be edible, yet their nu...

Trigonella foenum-graecum L. (fenugreek), a member of the legume family (Fabaceae), is a promising source of bioactive phytochemicals, which explains its traditional use for a variety of metabolic disorders including cancer. The current study aimed to evaluate extracts of fenugreek seeds and sprouts, and some of their constituents, to compare their...

Covering: up to 2019 The large and medicinally important tropical plant genus Plectranthus (Lamiaceae) was recently split into three separate genera on the basis of molecular and morphological evidence; Plectranthus sensu stricto, Coleus and Equilabium. We found striking differences between the diterpenoids which strongly support this taxonomic spl...

Melissa officinalis L. is used in traditional European and Iranian folk medicines to treat a plethora of neurological diseases including epilepsy. We utilized the in vitro and in vivo models of epilepsy to probe the anticonvulsant potentials of essential oil from M. officinalis (MO) to gain insight into the scientific basis for its applications in...

Ethnopharmacological relevance Malaria remains a serious and challenging disease. Traditional antimalarial medicines are largely based on plants, while ethnopharmacological research has inspired the development of antimalarial pharmaceuticals such as artemisinin. Antimalarial drug resistance is an increasing problem in Plasmodium species, and new t...

The Useful Plants and Fungi of Colombia project is a 2.5-year initiative led by Royal Botanic Gardens, Kew in collaboration with the Alexander von Humboldt Biological Resources Research Institute. Its aim is to develop pathways to enhance nature’s contribution to people in Colombia by increasing, consolidating and making accessible the knowledge of...

Never before has the biosphere, the thin layer of life we call home, been under such intensive and urgent threat. Deforestation rates have soared as we have cleared land to feed ever-more people, global emissions are disrupting the climate system, new pathogens threaten our crops and our health, illegal trade has eradicated entire plant populations...

Societal Impact Statement Biodiversity is essential to food security and nutrition locally and globally. By reviewing the global state of edible plants and highlighting key neglected and underutilized species (NUS), we attempt to unlock plant food resources and explore the role of fungi, which along with the wealth of traditional knowledge about th...

Societal Impact Statement Plants and fungi have provided, or inspired, key pharmaceuticals for global health challenges, including cancer, heart disease, dementia, and malaria, and are valued as traditional medicines worldwide. Global demand for medicinal plants and fungi has threatened certain species, contributing to biodiversity loss and depleti...

Kew’s State of the World’s Plants and Fungi project provides assessments of our current knowledge of the diversity of plants and fungi on Earth, the global threats that they face, and the policies to safeguard them. Produced in conjunction with an international scientific symposium, Kew’s State of the World’s Plants and Fungi sets an important inte...

Parkinson's disease (PD) pathology is characterised by distinct types of cellular defects, notably associated with oxidative damage and mitochondria dysfunction, leading to the selective loss of dopaminergic neurons in the brain's substantia nigra pars compacta (SNpc). Exposure to some environmental toxicants and heavy metals has been associated wi...

Enset (Ensete ventricosum) is a major starch staple and food security crop for 20 million people. Despite substantial diversity in morphology, genetics, agronomy and utilization across its range, nutritional characteristics have only been reported in relatively few landraces. Here, we survey nutritional composition in 22 landraces from three enset...

A therapeutic solution to the coronavirus disease 2019 (COVID-19) pandemic is urgently needed, but new drug discovery and development are lengthy processes. Pharmaceuticals derived from plants and fungi remain important in our armory against numerous diseases (1, 2), yet much of plant and fungal biodiversity remains unexplored for drug discovery (3...

Cognitive decline can occur with normal ageing and in age‐related brain disorders, such as mild cognitive impairment and dementia, including Alzheimer's disease, with limited pharmacological therapies available. Other approaches to reduce cognitive decline are urgently needed, and so, the role of dietary interventions or nutraceuticals has received...

The Mediterranean diet consisting of fresh fruit and vegetables, olive oil, and limited in meat and dairy, is associated with health benefits. In 2010, UNESCO recognised it as an intangible cultural heritage of humanity. In Jordan and Lebanon, their traditional East Mediterranean diet includes wild collected edible plants. We aim to understand whic...

More than 31,000 useful plant species have been documented to fulfil needs and services for humans or the animals and environment we depend on. Despite this diversity, humans currently satisfy most requirements with surprisingly few plant species; for example, just three crops – rice, wheat and maize – comprise more than 50% of plant derived calori...

A multilateral investigation of Enset (Ensete ventricosum (Welw.) Cheesman: Musaceae) on its biology, on-farm diversity, nutritional composition, biochemistry, seed germination physiology and floral anatomy (morphology) of selected landraces had been made.

Perilla frutescens is cultivated in East Asian countries including Thailand, and the nutlets (single‐seeded fruits) are used as traditional and medicinal food. Perilla nutlets extracted by ethyl acetate (EA), 80% ethanol (Eth), and hot water (HW) sequentially were chemically characterized using high‐resolution accurate liquid chromatography‐mass sp...

Background: Extracts of several members of the monoterpene-rich Lamiaceae sub-family Nepetoideae, including those from the Salvia (sage), Melissa (Lemon balm) and Rosmarinus (rosemary) genera, evince cognitive and mood effects in humans that are potentially related to their effects on cholinergic and GABAergic neurotransmission. To date, despite pr...

Two new coffee relatives (tribe Coffeeae, Rubiaceae), discovered during botanical expeditions to Cameroon, are examined for generic placement, and the placement of three previously known species (Argocoffeopsis fosimondi, A. spathulata and Calycosiphonia pentamera) is reinvestigated using plastid sequence (accD-psa1, rpl16, trnL-F) and morphologica...

Best scoring ML tree for the concatenated dataset, with bootstrap values equal or higher than 70% displayed above the branches. (TIF)

Voucher information and GenBank accession numbers for taxa used in this study. A dash indicates that the region was not sampled. Voucher specimens are deposited in the following herbaria: BR = National Botanic Garden of Belgium, Meise; DSM = University of Dar es Salaam; K = Royal Botanic Gardens, Kew; TAN = Parc de Tsimbazaza, Antananarivo; YA = Na...

Concatenated sequence alignment, with sequences from the plastid markers rpl16, trnL-F and accD-psa1. (FAS)

A new genus Kindia (Pavetteae, Rubiaceae) is described with a single species, Kindia gangan, based on collections made in 2016 during botanical exploration of Mt Gangan, Kindia, Republic of Guinea in West Africa. The Mt Gangan area is known for its many endemic species including the only native non-neotropical Bromeliaceae Pitcairnia feliciana. Kin...

Concatenated alignment of the chloroplast sequence data (rps16 and trnT-F)

Majority consensus multiple-locus BI cladogram with the associated PP values and the BS values of the multiple-locus ML tree Only PP above 0.80 and BS values above 75% are shown. Nodes with PP < 0.5 support have been collapsed. Inset tree shows the branch lengths.

The traditional practice of eating the flowers of Clitoria ternatea L. or drinking their infusion as herbal tea in some of the Asian countries is believed to promote a younger skin complexion and defend against skin aging. This study was conducted to investigate the protective effect of C. ternatea flower water extract (CTW) against hydrogen peroxi...

A phytochemical and biological investigation of the endemic Mascarene Aloes (Aloe spp.), including A. tormentorii (Marais) L.E.Newton & G.D.Rowley, A. purpurea Lam, A. macra Haw., A. lomatophylloides Balf.f and A. vera (synonym A. barbadensis Mill.), which are used in the traditional folk medicine of the Mascarene Islands, was initiated. Methanolic...

The Mascarene Aloes are used in the traditional pharmacopoeia against various ailments including cutaneous diseases and as antispasmodics. Scientific evidence to support these claims is non-existent and mainly based on the scientific repute of A. vera. The antioxidant profile of methanolic leaf extracts of A. purpurea Lam., A. tormentorii (Marais)...

Alzheimer's disease (AD) is reaching epidemic proportions yet treatment strategies are limited and are restricted to providing symptomatic relief for the cognitive and behavioral and psychological symptoms of dementia (BPSD). Chinese herbal medicine (CHM) has been a valuable source of medicines for centuries and research has burgeoned in recent yea...

Objective : To evaluate for the first time the effects of a combination of sage, rosemary and melissa (Salvia officinalis L., Rosmarinus officinalis L. and Melissa officinalis L.; SRM), traditional European medicines, on verbal recall in normal healthy subjects. To devise a suitable study design for assessing the clinical efficacy of traditional he...

Medicinal plants used to manage diabetes in Central America

Focus on medicinal plants.

The beautifully illustrated Gardener’s Companion to Medicinal Plants is an A-Z of healing plants and home remedies, featuring more than 270 plants used for their medicinal properties, as well as 24 practical projects for homemade teas, oils, tinctures and creams with a tradition of safe use. Each plant is illustrated with a beautiful work of botani...

Ethnopharmacological relevance: Every year between 1.2 and 5.5 million people worldwide are victims of snakebites, with about 400,000 left permanently injured. In Central America an estimated 5,500 snakebite cases are reported by health centres, but this is likely to be an underestimate due to unreported cases in rural regions. The aim of this stu...

The data described in this article is related to the review article “Medicinal plants used in the traditional management of diabetes and its sequelae in Central America: a review” (Giovannini et al., 2016) [1]. We searched publications on the useful plants of Central America in databases and journals by using selected relevant keywords. We then ext...

Ethnopharmacological relevance: Globally 387 million people currently have diabetes and it is projected that this condition will be the 7th leading cause of death worldwide by 2030. As of 2012, its total prevalence in Central America (8.5%) was greater than the prevalence in most Latin American countries and the population of this region widely us...

The cultivation of apples (Malus x domestica) can be traced back for thousands of years to Asia and to Malus sieversii, which grows in temperate forests of central Asia. As the apple spread through Asia, into Europe, Russia and then into the Americas, Australia, and New Zealand, the number of locally grown cultivars increased. The difference in the...

Objectives The Jordanian ‘Melissa’, (Aloysia citrodora) has been poorly studied both pharmacologically and in the clinic. Essential oils (EO) derived from leaves of A. citrodora were obtained by hydrodistillation, analysed by gas chromatography-mass spectrometry (GC-MS) and were investigated for a range of neurobiological and pharmacological prope...

Purpose of review: Intake of dietary phytochemicals has frequently been associated with health benefits. Noninfectious diseases including cardiovascular disease (CVD), cancer and diabetes are major causes of death, whereas dementia cases are also increasing to 'epidemic' proportion. This review will focus on recent progress on mechanisms underlyin...

Melissa officinalis (Mo) and Lavandula angustifolia (La) essential oils and their major constituents ((E) caryophyllene, caryophyllene oxide, geranyl acetate, linalool, nerol, Oct-1-en-3-ol, 3-Octanone, myrcene, allo-ocimene, p-cymene and α- terpineol) assessed by GC-MS) which are shared by these two essential oils were probed in an attempt to iden...

Neurodegenerative diseases include a range of disorders that involve dysfunction of the central nervous system, due to degeneration of neurons and associated pathological processes. These diseases include Lewy body dementia, vascular dementia, Huntington’s, Parkinson’s (PD), and Alzheimer’s diseases (AD). Treatment strategies are limited and freque...

Ethnobotany encompasses the cultural uses of plants by humans, including their uses as medicines (ethnopharmacology). The reputed medicinal properties of plants have been documented for centuries in different cultures, and there are many plant species that have been traditionally used for memory disorders, which are now being explored to determine...

This review focuses on recent developments in the use of natural products as therapeutics for Alzheimer's disease. The compounds span a diverse array of structural classes and are organized according to their mechanism of action, with the focus primarily on the major hypotheses. Overall, the review discusses more than 180 compounds and summarizes 4...

An escalating "epidemic" of diseases like Alzheimer's has not yet been met by effective symptomatic treatments or preventative strategies. Among a few current prescription drugs are cholinesterase inhibitors including galantamine, originating from the snowdrop. Research into ethnobotanicals for memory or cognition has burgeoned in recent years. Bas...

The major constituents of leaf extracts of Iris fulva KER GAWL. comprised a known flavone C-glycoside, 5,4'-dihydroxy-7-methoxyflavone-6-C-(6‴-O-(E)-p-coumaroyl-β-glucopyranosyl)(1‴→2″)-β-glucopyranoside (1) and the new monoterpene glycoside, linalyl-6'-O-(3″-hydroxy-3″-methylglutaroyl)-β-D-glucopyranoside (2), both of which were prominent componen...

Dementia pathologies such as Alzheimer's disease (AD) are reaching epidemic proportions, yet they are not successfully managed by effective symptomatic treatments. Only five drugs have been developed to alleviate cognitive symptoms, and more effective and safe treatments are needed for both the cognitive symptoms and behavioural and psychological s...

Behavioural and psychological symptoms (BPSD) are frequent in people with Alzheimer's disease and cause considerable stress to patients and their carers. Antipsychotics have been widely used as a first-line treatment, resulting in an estimated 1,800 excess strokes and 1,600 excess deaths in the UK alone. Safe and effective alternatives are urgently...

Withania somnifera L. Dunal (Solanaceae), also known as 'ashwagandha' in Sanskrit and as 'Indian ginseng', is used widely in Ayurvedic medicine as a nerve tonic and memory enhancer, with antiaging, antistress, immunomodulatory and antioxidant properties. There is a paucity of data on the potential neuroprotective effects of W. somnifera root, as tr...

The volatile compounds from the pericarps of Illicium anisatum L., Illicium brevistylum A.C.Sm., Illicium griffithii Hook.f. & Thomson, Illicium henryi Diels, Illicium lanceolatum A.C.Sm., Illicium majus Hook.f. & Thomson, Illicium micranthum Dunn, and Illicium verum Hook.f. were examined by thermal desorption-gas chromatography-mass spectrometry (...

In traditional practices of medicine, numerous plants have been used to alleviate memory impairment both in healthy individuals and those with disease states which are now recognised as specific cognitive disorders such as Alzheimer’s disease (AD). An ethnopharmacological approach has provided leads to identify plants and their compounds that may h...

Both Melissa officinalis (Mo) and Lavandula angustifolia (La) essential oils have putative anti-agitation properties in humans, indicating common components with a depressant action in the central nervous system. A dual radioligand binding and electrophysiological study, focusing on a range of ligand-gated ion channels, was performed with a chemica...

Since the alkaloid galanthamine occurring in genera such as Narcissus and Galanthus is an inhibitor of acetylcholinesterase (AChE) and is used in the treatment of dementia, and as a number of plant essential oils are also currently being explored as therapeutic agents, we examined the cholinesterase inhibitory effects of Narcissus poeticus L. absol...

A dual radioligand binding and electrophysiological study, focusing on a range of ligand-gated ion channels, was performed with a chemically-validated essential oil derived from Melissa officinalis (MO), which has shown clinical benefit in treating agitation. MO inhibited binding of [35S] t-butylbicyclophosphorothionate (TBPS) to the rat forebrain...

Although in vivo models give a more accurate reflection of the activity of substances used in traditional medicine, their use in many countries is severely restricted due to economic and ethical concerns, and this has resulted in the widespread use of in vitro tests in ethnopharmacological studies. Such tests are very useful where the identity of c...

Agitation is a common symptom in people with severe dementia and is often treated with neuroleptic drugs which demonstrate severe side effects and limited efficacy. An encouraging alternative treatment involves the use of aromatherapy using essential oils from melissa (Melissa officinalis L.) or lavender (Lavandula angustifolia Mill.), both of whic...

This review describes 183 compounds obtained from plants and fungi which have been shown to inhibit acetylcholinesterase. The mechanism of action of cholinesterase, together with the binding sites, and, where this is known, the mode of action of inhibitors is described. The relative activities of the different compounds are recorded. The strongest...

The two major neurodegenerative diseases Alzheimer's disease (AD) and Parkinson's disease (PD) are characterised by low levels in the brain of the neurotransmitters acetylcholine (ACh) and dopamine (DA), respectively. Clinical treatment of these two conditions is palliative and relies, in most cases, on improving stimulation at the relevant recepto...