Plants used to treat diabetes in Sri Lankan Siddha Medicine - An ethnopharmacological review of historical and modern sources

Production and purification of fucoxanthins and β-carotenes from Halopteris scoparia and their effects on digestive enzymes and harmful bacteria

ABSTRACTAlgae constitute a significant part of marine biodiversity. They represent a renewable source of bioactive metabolites from drug development and therapeutic fields. Fucoxanthin and β-carotene from the brown macroalgae Halopteris scoparia, were extracted using conventional organic solvent extraction, then purified, to homogeneity, based on various chromatographic principles. Their effects on digestive enzymes and harmful bacteria were investigated. The capacities of both purified pigments to inhibit α-amylase and trypsin enzymes were evaluated. Purified fucoxanthin and β-carotene exhibited interesting α-amylase inhibition activities, with IC50 of 300 and 500 µg/mL, respectively. Moreover, trypsin inhibition activities were detected using purified these two pigments. The antibacterial potential of the purified pigments was evaluated. β-carotene showed to be a great antibacterial natural compound against gram-positive and gram-negative bacteria such as Listeria monocytogenes, Staphylococcus aureus and Salmonella enterica with Minimal Inhibitory Concentration (MIC) of about 0.225, 0.1125, 0.225 µg/mL, respectively. Those findings are in favor of the exploitation of H. scoparia pigments in therapeutic fields as an antidiabetic source directly by the inhibition of α-amylase and trypsin as well as antibacterial agents against gastrointestinal infections.

Effect of Crocus sativus L. (saffron) and crocin in the treatment of patients with type-2 diabetes mellitus: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Crocus sativus L. (saffron, Iridaceae) has been traditionally used for thousands of years as herbal medicine for many diseases, including type-2 diabetes mellitus (T2DM), especially in Sri Lanka. Systematic reviews and meta-analysis on C. sativus for T2DM value traditional knowledge about this species.

AIM OF THE STUDY

To assess the effectiveness of C. sativus powdered plant, hydroethanolic extract and crocin in reducing fasting blood sugar (FBG), glycated hemoglobin (HbA1c), blood pressure, and other metabolic parameters in patients with T2DM.

MATERIAL AND METHODS

Systematic review and meta-analysis based on searches in PubMed, Embase, and Cochrane, including all randomized clinical trials (RCTs) published before January 2, 2023. Two independent reviewers extracted the data and assessed the risks of bias. The effects of C. sativus and crocin were assessed on glycemic, metabolic, and blood pressure parameters. Weighted (WMD) or standardized (SMD) mean differences (before-after) and 95% confidence intervals (95%CI) of the outcomes were extracted or estimated and meta-analyses were conducted using RevMan 5.4 (Cochrane Collaboration). This protocol was registered in PROSPERO (#CRD42023390073).

RESULTS

Fifteen of 29 studies were included. Saffron powdered plant decreased AST (WMD -1.19, 95%CI -2.24, -0.13), but increased BMI (WMD 0.56, 95%CI 0.07, 1.05); saffron extract decreased HbA1c (WMD -0.35, 95%CI -0.65, -0.06), FBG (WMD -26.90, 95%CI -38.87, -14.93), creatinine (WMD -0.12, 95%CI -0.19, -0.05), and total cholesterol (WMD -9.29, 95%CI -18.25, -0.33); and crocin decreased HbA1c (WMD -0.43, 95%CI -0.66, -0.20), FBG (WMD -14.10, 95%CI -22.91, -5.30), and systolic blood pressure (WMD -8.18, 95%CI -12.75, -3.61), but increased creatinine levels (WMD 0.24, 95%CI 0.17, 0.32). Of the 15 included studies, 14 had a moderate risk of bias, and one study had a low risk of bias.

CONCLUSION

C. sativus (saffron) powdered plant, extract, and crocin have potential as an adjunct treatment for T2DM, improving control of metabolic and clinical parameters. However, C. sativus extract seems to be superior because it was effective in more parameters and did not induce adverse effects. Since many studies were at moderate risk of bias, further high-quality research is needed to firmly establish the clinical efficacy of this plant.

Recent developments in nanoparticles for the treatment of diabetes

Changes in the homeostasis of blood sugar levels are a hallmark of diabetes mellitus, an incurable metabolic condition, for which the first-line treatment is the subcutaneous injection of insulin. However, this method of administration is linked to low patient compliance because of the possibility of local infection, discomfort and pain. To enable the administration of the peptide through more palatable paths without requiring an injection, like by oral routes, the use of nanoparticles as insulin carriers has been suggested. The use of nanoparticles usually improves the bioavailability and physicochemical stability of the loaded medicine. The utilisation of several forms of nanoparticles (like lipid and polymeric nanoparticles, micelles, dendrimers, liposomes, niosomes, nanoemulsions and drug nanosuspensions) is discussed in this article as a way to improve the administration of various oral hypoglycaemic medications when compared to conventional treatments.

Ethnomedicinal Knowledge of Plants Used in Nonconventional Medicine in the Management of Diabetes Mellitus in Kinshasa (Democratic Republic of the Congo)

Background

People with diabetes, herbalists, and traditional medicine practitioners (TMPs) from Kinshasa use plants to treat diabetes, but no study has inventoried the plants used by these populations. The present study was conducted to identify the plants used in Kinshasa to treat diabetes mellitus.

Methods

The survey conducted in the form of a semistructured interview between March 2005 and August 2006 made it possible to collect ethnobotanical information from people with diabetes (n = 126), herbalists (n = 80), and TMPs (n = 120).

Results

The 326 subjects consulted (sex ratio M/F = 0.6, age 51 ± 7 years, and experience: 17 ± 5 years) provided information on 71 plants, most of which are trees (35%), belonging to 38 families dominated by Fabaceae (19.7%) and indicated in 51 other cases of consultation dominated by malaria (12%). From these 71 plants derived, 86 antidiabetic recipes were administered orally, where the leaf is the most used part (>50%) and the decoction (>46%) is the most common mode of preparation. This study reports for the first time the antidiabetic use of 11 species, among which Tephrosia vogeliiX (0.08), Chromolaena corymbosaX (0.06), and Baphia capparidifoliaX (0.06) present the highest consensus indexes (CI) and Marsdenia latifoliaW (UVp = 0.08) and Rauvolfia manniiX (UVp = 0.06) present the highest UVs.

Conclusion

The results show that Kinshasa people treat diabetes using several plants. Some are specific to the ecological environment; others are used in other regions. Pharmacological studies are underway to assess the therapeutic efficacy of these plants.

A multivariate and quantitative assessment of medicinal plants used by the indigenous Malayali tribes in the Javadhu hills of Tiruvannamalai district, Tamil Nadu, India

The study of medicinal plants with their traditional uses and related pharmacological studies has received more attention during the past several decades around the world. The Malayali tribes of the Javadhu Hills in the Eastern Ghats rely heavily on a system of traditional medicine for healthcare. A qualitative ethnographic method with a semi-structured questionnaire was used to interview 52 people across 11 localities in the Javadhu Hills. In the data analysis, descriptive statistics such as Use reports (UR), frequency of citations (FC), relative frequency of citations (RFC), informant agreement ratio (IAR), fidelity level (FL), and informant consensus factor (FIC) were studied. In the current investigation, 146 species from 52 families and 108 genera were discovered to treat 79 diseases. Leguminosae and Apocynaceae were the dominant families (12 species each). The most frequently used life form was the herb and the plant part were the leaf. The majority were being harvested from natural resources. Most medicines were taken orally. The most frequently cited species are Moringa oleifera and Syzygium cumini. The illnesses were divided into 21 categories. The majority of the plants mentioned are utilised to increase human immunity and health. The principal ailment (general health) was revealed by two-way cluster analysis and PCA. The species Litsea decanensis, Phoebe paniculata, Commiphora caudata, etc., were new records for the Javadhu hills according to a comparison between the current study and previous local and regional research. Documenting novel ethnomedicinal species and their therapeutic applications will encourage more phytochemical and pharmacological research and may even result in the creation of new medications. Furthermore, the study's significant novelty is that principle component analysis and two-way cluster analysis clearly revealed that the species that are used to treat various diseases, as well as species that are closely associated with treating specific ailment categories, are distinct. Significantly, species recorded in this study rely on maintaining and improving general body health of humans.

Traditional mineral medicine realgar and Realgar-Indigo naturalis formula potentially exerted therapeutic effects by altering the gut microbiota

Introduction

Realgar has a long history ofuse in traditional medicines. However, the mechanism through which Realgar or Realgar-Indigo naturalis formula (RIF) exert therapeutic effects is only partially understood.

Methods

In this study, 60 feces and 60 ileum samples from rats administered with realgar or RIF were collected to examine the gut microbiota.

Results

The results showed that realgar and RIF influenced different microbiota in both feces and ileum. Compared with realgar, RIF at low dosage (0.1701 g/3 ml) significantly increased the microbiota diversity. LEfSe and random forest analyses showed that the bacterium Bacteroidales was significantly altered after RIF administration, and it was predicted that these microorganisms contribute to the inorganic arsenic metabolic process.

Discussion

Our results suggest that realgar and RIF may exert their therapeutic effects through influencing microbiota. The low dose of RIF had greater effects on increasing the diversity of microbiota, and Bacteroidales in feces might participate in the inorganic arsenic metabolic process to exert therapeutic effects for realgar.

Acacia jacquemontii ethyl acetate extract reduces hyperglycemia and pro-inflammatory markers while increasing endogenous antioxidant potential in alloxan-induced diabetic rats

Acacia jacquemontii possess has numerous traditional therapeutic uses. The rationale of this study was to investigate the role of Acacia jacquemontii ethyl acetate extract (AJEAE) in the downregulation of hyperglycemia. The current study was performed in two parts, in vitro, through characterization (high-performance liquid chromatography), estimation of total phenolic content, total flavonoid content, antioxidant (2,2-diphenyl-1-picrylhydrazylassay), and α-amylase inhibitory activities of the studied extract, and in vivo using Wistar rats in which animals were divided into five groups NC, DC, GL, AJEAE 250 mg/kg, and AJEAE 500 mg/kg. The effects of AJEAE on fasting plasma glucose, plasma insulin, HOMA-IR, oral glucose tolerance test, glycated hemoglobin (HBA1c), lipid profile, inflammatory cytokines (Interleukin-6, tumor necrosis factor-alpha), and oxidative stress markers (lipid peroxidation, nitic oxide, superoxide dismutase, catalase, glutathione peroxidase) were evaluated. Our findings confirmed the presence of quercetin, kaempferol, gallic acid, vanillic acid, syringic acid, M-coumaric acid, sinapic acid, chlorogenic acid, cinnamic acid, and ferulic acid in AJEAE. Total flavonoid and phenolic contents in AJEAE were 83.83 mg GAE/g and 77.06 mg QE/g, respectively. Significant inhibition of DPPH (69.470%/1 mg/ml) and α-amylase (71.8%/1 mg/ml) activities were exhibited by AJEAE. Alloxan-injected rats showed marked hyperglycemia and hypoinsulinemia, and increased inflammatory marker levels as compared to normal control (p < 0.001). Additionally, raised levels of triglyceride (139.7 ± 2.771), total cholesterol (198.7 ± 1.856), very low-density lipoprotein (33.43 ± 0.2728), low-density lipoprotein (155.5 ± 2.754), lipid peroxidation, and nitric oxide (p < 0.001) and decreased levels of high-density lipoprotein (17.20 ± 0.1732), superoxide dismutase, catalase, and glutathione peroxidase were observed in diabetic rats (p < 0.001). AJEAE significantly (p < 0.05) improved the aforementioned parameters and the protective efficacy was comparable to glibenclamide. Histopathological findings also evidenced the anti-hyperglycemic properties of AJEAE through regeneration of pancreatic β cells. Conclusively, our findings demonstrated the antihyperglycemic, antihyperlipidemic, antioxidant, anti-inflammatory, and pancreatic beta β cell regenerative properties of AJEAE against alloxan-induced diabetes.

Arsenic compounds: The wide application and mechanisms applied in acute promyelocytic leukemia and carcinogenic toxicology

Arsenic (As), as well as its various compounds have been widely used for nearly 4000 years either as drugs or poisons. These compounds are valuable in the treatment of various diseases ranging from dermatosis to cancer, thereby emphasizing their important roles as therapeutic agents. The ability of As compounds, especially arsenic trioxide (ATO) in the treatment of acute promyelocytic leukemia (APL), has fundamentally altered people's understanding of the poison, and has become a major factor in the re-emergence of Western medicine candidates to treat leukemia and other solid tumors. However, long-term exposure to As has been correlated with numerous disadvantageous influences on health, particularly carcinogenesis. Importantly, accumulating evidence suggests that biotransformation of As, as a step to eliminate As from the human body, can induce alterations at the genetic and epigenetic levels, resulting in therapeutic effects or carcinogenesis. In this article, we aimed to provide a systematic overview of the primary contributions associated with As and its compounds, as well as the detailed mechanisms applied in APL cells and carcinogenic toxicology. This review may help to understand the underlying mechanisms and safe wide clinical applications of medicinal As along with its compounds.

Geopolitics of bitterness: Deciphering the history and cultural biogeography of Quassia amara L

ETHNOPHARMACOLOGICAL RELEVANCE

Quassia amara L. recently came into the spotlight in French Guiana, when it became the object of a biopiracy claim. Due to the numerous use records throughout the Guiana shield, at least since the 18th century, a thorough investigation of its origin seemed relevant and timely. In the light of the Convention on Biological Diversity (CBD) and the Nagoya protocol, questions about the origin of local knowledge are important to debate.

AIM OF THE STUDY

Defining cultural biogeography as the dynamics through space and time of biocultural complexes, we used this theoretical framework to shed light on the complex biogeographical and cultural history of Q. amara. We explored in particular the possible transfer of medicinal knowledge on an Old World species to a botanically related New World one by enslaved Africans in Suriname.

MATERIALS AND METHODS

Historical and contemporary literature research was performed by means of digitized manuscripts, archives and databases from the 17th to the 21st century. We retrieved data from digitized herbarium vouchers in herbaria of the Botanic Garden Meise (Belgium); Naturalis Biodiversity Center (the Netherlands); Missouri Botanical Garden, the Smithsonian National Museum of Natural History, the Field Museum (USA); Royal Botanic Gardens Kew (UK); the IRD Herbarium, French Guiana and the Museum National d'Histoire Naturelle (France). Vernacular names were retrieved from literature and herbarium specimens and compared to verify the origin of Quassia amara and its uses.

RESULTS

Our exploration of digitized herbarium vouchers resulted in 1287 records, of which 661 were Q. amara and 636 were Q. africana. We observed that the destiny of this species, over at least 300 years, interweaves politics, economy, culture and medicine in a very complex way. Quassia amara's uses are difficult to attribute to specific cultural groups: the species is widely distributed in Central and South America, where it is popular among many ethnic groups. The species spread from Central to South America during the early 18th century due to political and economic reasons. This migration possibly resulted from simultaneous migration by religious orders (Jesuits) from Central America to northern South America and by Carib-speaking Amerindians (from northern South America to Suriname). Subsequently, through colonial trade networks, Q. amara spread to the rest of the world. The absence of African-derived local names in the Guiana shield suggests that Q. africana was not sufficiently familiar to enslaved Africans in the region that they preserved its names and transferred the associated medicinal knowledge to Q. amara.

CONCLUSIONS

Cultural biogeography has proven an interesting concept to reconstruct the dynamics of biocultural interactions through space and time, while herbarium databases have shown to be useful to decipher evolution of local plant knowledge. Tracing the origin of a knowledge is nevertheless a complex adventure that deserves time and interdisciplinary studies.

Middle East Medicinal Plants in the Treatment of Diabetes: A Review

Diabetes is a global health problem, and the number of diabetic patients is in continuous rise. Conventional antidiabetic therapies are associated with high costs and limited efficiency. The use of traditional medicine and plant extracts to treat diabetes is gaining high popularity in many countries. Countries in the Middle East region have a long history of using herbal medicine to treat different diseases, including diabetes. In this review, we compiled and summarized all the in vivo and in vitro studies conducted for plants with potential antidiabetic activity in the Middle East region. Plants of the Asteraceae and Lamiaceae families are the most investigated. It is hoped that this review will contribute scientifically to evidence the ethnobotanical use of medicinal plants as antidiabetic agents. Work has to be done to define tagetes, mechanism of action and the compound responsible for activity. In addition, safety and pharmacokinetic parameters should be investigated.

Natural products in diabetes research: quantitative literature analysis

The current study aimed to identify which natural products and which research directions are related to the major contributors to academic journals for diabetes therapy. Bibliometric data were extracted from the Web of Science online database using the search string TOPIC = (''natural product*' OR ''natural compound*' OR ''natural molecule*' OR 'phytochemical*' OR ''secondary metabolite*') AND TS = ('diabet*') and analysed by a bibliometric software, VOSviewer. The search yielded 3694 publications, which were collectively cited 80,791 times, with an H-index of 117 and 21.9 citations per publication on average. The top-contributing countries were India, the USA, China, South Korea and Brazil. Curcumin, flavanone, resveratrol, carotenoid, polyphenols, flavonol, flavone and berberine were the most frequently cited natural products or compound classes. Our results provide a brief overview of the major directions of natural product research in diabetes up to now and hint on promising avenues for future research.

A review of traditional uses, phytochemistry and pharmacology of the genus Indigofera

ETHNOPHARMACOLOGICAL RELEVANCE

Indigofera is the third-largest genus in the family of Fabaceae, with approximately 750 species. It is distributed across all tropical regions. Indigofera species are widely employed in traditional medicine all around the world, against many ailments. Thus, based on these medicinal properties, various investigations have been undertaken in order to appraise the pharmacological activities and the chemical composition of these species. A recent paper provides a summary of the phytochemistry and pharmacology of the genus Indigofera. Consequently, this review is a continuation of this previous study by updating some data and adding information about the phylogeny and traditional uses of the genus.

AIM OF THE STUDY

To provide an overview of the phylogeny, traditional uses, phytochemistry, pharmacology and toxicity of the genus Indigofera, and to identify the remaining gaps and thus supply a basis for further investigations.

MATERIALS AND METHODS

A review of the literature was performed by consulting scientific databases such as 'ScienceDirect', 'PubMed', 'Google Scholar' and 'SpringerLink' and using the keyword Indigofera.

RESULTS

Over 60 Indigofera species are reported in traditional medicine. The uses depend on the country and the species, but similarities have been noticed. Indeed, treatments of gastrointestinal disorders, inflammatory conditions and pain, skin ailments, and respiratory and infectious diseases are recurring. Phytochemical studies have led to the identification of more than 200 compounds, notably flavonoids and terpenoids. Many pharmacological activities have been demonstrated, particularly antimicrobial, cytotoxic and anti-inflammatory activities, and thus allowed to assert most of the traditional uses of the genus. Some active compounds have been isolated and have shown remarkable therapeutic potential, like the alkaloid indirubin, which is currently being clinically trialed.

CONCLUSIONS

The data on the genus Indigofera are extensive, but gaps still remain. Indeed, some promising species have not been assessed for their phytochemistry and/or pharmacology and thus remain unexplored. Moreover, relatively few active compounds have been isolated and tested for their biological activity, and studies to explain their mechanism of action are nearly inexistent. Furthermore, some pharmacological studies have inappropriate methodologies that make the results difficult to interpret. Consequently, further in-depth and relevant research is required to supplement the knowledge on this wide-ranging genus and to confirm its reported therapeutic potential.

A Systematic Review on Synthetic Drugs and Phytopharmaceuticals Used to Manage Diabetes

BACKGROUND

Diabetes is a multifactorial disease and a major cause for many microvascular and macrovascular complications. The disease will ultimately lead to high rate mortality if it is not managed properly. Treatment of diabetes without any side effects has always remained a major challenge for health care practitioners.

INTRODUCTION

The current review discusses the various conventional drugs, herbal drugs, combination therapy and the use of nutraceuticals for the effective management of diabetes mellitus. The biotechnological aspects of various antidiabetic drugs are also discussed.

METHODS

Structured search of bibliographic databases for previously published peer-reviewed research papers was explored and data was sorted in terms of various approaches that are used for the treatment of diabetes.

RESULTS

More than 170 papers including both research and review articles, were included in this review in order to produce a comprehensive and easily understandable article. A series of herbal and synthetic drugs have been discussed along with their current status of treatment in terms of dose, mechanism of action and possible side effects. The article also focuses on combination therapies containing synthetic as well as herbal drugs to treat the disease. The role of pre and probiotics in the management of diabetes is also highlighted.

CONCLUSION

Oral antihyperglycemics which are used to treat diabetes can cause many adverse effects and if given in combination, can lead to drug-drug interactions. The combination of various phytochemicals with synthetic drugs can overcome the challenge faced by the synthetic drug treatment. Herbal and nutraceuticals therapy and the use of probiotics and prebiotics are a more holistic therapy due to their natural origin and traditional use.

Therapeutic potential of medicinal plants for the management of scabies

Sarcoptes scabiei (S. scabiei), a parasite mite which causes scabies disease resulting in serious public health concern. The long-term scabies disease can lead to complications such as septicemia, acute post-streptococcal glomerulonephritis, heart disease, and secondary infections. Timely treatment to the affected patients is required to control the disease and get rid of the causative agent. Delayed diagnosis and inappropriate treatment can lead to serious consequences. The most common treatment strategy is the use of allopathic medicines which can immediately relieve the patient but have the drawback of side effects. The safe and cost-effective alternative treatment strategy is the use of medicinal plants which have beneficial therapeutic potential against variety of diseases due to the presence of many bioactive phytoconstituents with no or minimal side effects. For the present review, the published articles describing scabies disease and its phytotherapeutic modalities were searched through different data bases including Google Scholar, PubMed, Medline, and ScienceDirect using the keywords like S. scabiei, prevalence of scabies disease, and phytotherapy of scabies. A large number of medicinal plants, such as Melaleuca alternifolia, Curcuma longa, Azadirachta indica, Rosmarinus officinalis, Capsicum annuum, Cinnamomum camphor, Solanum nigrum, and Eupatorium perfoliatum, have been reviewed for the promising future treatments of scabies. All the studied plants have many bioactive compounds with potential therapeutic effects against scabies and can be utilized for therapeutic purposes for this disease. This literature study has limitations because of the lack of sufficient data due to limited pre-clinical trials in this particular area. This review provides a baseline to explore the therapeutic potential of these medicinal plants against skin diseases. However, extensive studies are required to identify, authenticate, and characterize the bioactive compounds present in these plants which may lead to value addition in pharmaceutical industries providing the cost-effective way of treatment with minimal side effects.

Chemical Compositions of Metals in Bhasmas and Tibetan Zuotai Are a Major Determinant of Their Therapeutic Effects and Toxicity

Minerals are alchemically processed as Bhasmas in Ayurvedic medicines or as Zuotai in Tibetan medicines. Ayurveda is a knowledge system of longevity and considers the mineral elixir made from “nature” capable of giving humans perpetual life. Herbo-metallic preparations have a long history in the treatment of various diseases in India, China, and around the world. Their disposition, pharmacology, efficacy, and safety require scientific evaluation. This review discusses the Bhasmas in Ayurvedic medicines and Zuotai in Tibetan medicines for their occurrence, bioaccessibility, therapeutic use, pharmacology, toxicity, and research perspectives. A literature search on Mineral, Bhasma, Ayurvedic medicine, Zuotai, Tibetan medicine, and Metals/metalloids from PubMed, Google and other sources was carried out, and the relevant papers on their traditional use, pharmacology, and toxicity were selected and analyzed. Minerals are processed to form Bhasma or Zuotai to alter their physiochemical properties distinguishing them from environmental metals. The metals found in Ayurveda are mainly from the intentional addition in the form of Bhasma or Zuotai. Bhasma and Zuotai are often used in combination with other herbals and/or animal-based products as mixtures. The advanced technologies are now utilized to characterize herbo-metallic preparations as Quality Assurance/Quality Control. The bioaccessibility, absorption, distribution, metabolism, and elimination of herbo-metallic preparations are different from environmental metals. The pharmacological basis of Bhasma in Ayurveda and Zuotai in Tibetan medicines and their interactions with drugs require scientific research. Although the toxic potentials of Bhasma and Zuotai differ from environmental metals, the metal poisoning case reports, especially lead (Pb), mercury (Hg), and arsenic (As) from inappropriate use of traditional medicines, are increasing, and pharmacovigilance is desired. In risk assessment, chemical forms of metals in Bhasma and Zuotai should be considered for their disposition, efficacy, and toxicity.

Siddha Medicine in Eastern Sri Lanka Today-Continuity and Change in the Treatment of Diabetes

Diabetes is affecting the social and economic developments in developing countries like Sri Lanka. Siddha Medicine (Tamil Medicine) is mostly practiced in the Eastern and Northern Provinces of Sri Lanka. Our recent review of Sri Lankan Siddha historical documents identified 171 plant species used to prepare anti-diabetic preparations. On the other hand, there is no study of plants currently used to treat diabetes in Sri Lankan Siddha Medicine. Hence, the aim of this study is to identify and document the plant species currently used in anti-diabetic preparations in Eastern Province, also enabling a comparative analysis with historical uses. Further, assessing the level of scientific evidence (in vitro, in vivo, and clinical studies) available for recorded species. A systematically prepared questionnaire was used to conduct an ethnobotanical survey with 27 Siddha healers residing in Eastern Province to identify the currently used anti-diabetic plants. Furthermore, Web of Science electronic database was used to assess the level of scientific evidence available excluding widespread and very well studied species. On average 325 diabetic patients were seen by 27 healers per week. Interestingly, inorganic substances, and animal parts used as ingredients in historical anti-diabetic preparations are currently not used in Eastern Province. A total of 88 plant species from 46 families were reported in this study. Syzygium cumini (L.) Skeels was the most frequently recorded species and the largest number of taxa are from Fabaceae. Remarkably, one third of reported species were not stated in Sri Lankan Siddha historical documents. The highest number of plant species (59%) have been studied up to an in vivo level followed by no scientific evidence for anti-diabetic activity found (27%), clinical evidence (10%), and in vitro (2%). This is the first ethnobotanical study of plants used to treat diabetes by Siddha healers in the Eastern Province in Sri Lanka. Moreover, awareness should be created to the diabetics about the side effects of herb-drug interactions and complications caused by taking both herbal preparations and biomedical drugs.

Applicability and reliability of the glucose oxidase method in assessing α-amylase activity

Glucose oxidase (GOD) is an enzyme widely used in glucose monitoring systems owing to its high specificity towards glucose. However, in our previous work maltose was found to show significant interaction with GOD and based on this observation, a novel microplate-based method was developed to assess α-amylase inhibitory activity (GOD method). Concerns regarding the interaction of GOD with maltose has limited the widespread use of the GOD method in assessing α-amylase activity. The present paper provides answers to concerns regarding the interaction of GOD with maltose using HPLC studies and application of the GOD method in assessing α-amylase activity. According to the results, the newly developed GOD method can be considered as a well-suited method for the determination of α-amylase activity and as an easy method to do kinetic studies compared to other available methods.

A study on food-medicine continuum among the non-institutionally trained siddha practitioners of Tiruvallur district, Tamil Nadu, India

BACKGROUND

Medicinal properties of the food species are one of the poorly documented and important areas of ethnopharmacology. The present survey quantitatively documented the medicinal foods prescribed by the non-institutionally trained siddha practitioners of Tiruvallur district of Tamil Nadu.

METHODS

Field work was carried out between December 2014 and April 2017 using a questionnaire. The illnesses mentioned by the informants were grouped as illness categories on the basis of emic perceptions. Sufficiency of sampling of this survey was assessed by plotting the cumulative number of UR and Shannon-Wiener's index. The indices such as informant consensus factor (FIC), Index of Agreement on Remedies (IAR), and Cultural Food Significance Index (CFSI) were calculated.

RESULTS

This study documented 165 medicinal foods used by 82 non-institutionally trained siddha practitioners of Tiruvallur district, and 73.93% of these preparations were plant based. Among the animal taxa, 82.05% were represented by fish taxa. The illness category gastrointestinal ailments is the majorly cited illness category treated with plant-based formulations. The illness categories viz., gastrointestinal ailments, hemorrhoids, and neural ailments had high consensus under the group of plant-based medicinal foods. In animal-based medicinal foods, kapha ailments had gained 23.07% of UR. The illness categories such as bone fractures, male reproductive ailments, blood ailments, and anabolic had high FIC values.

CONCLUSIONS

Deeper studies on different dietary cultures of India may help to derive better interpretations on food-medicine continuum. This study identified some important claims such as the use of citron, pomegranate and Solanum americanum (gastrointestinal ailments), Abutilon indicum, onions and elephant foot yam (hemorrhoids), Boerhavia diffusa (urinary ailments), Moringa oleifera (anemia), Aloe vera (gynecological ailments), Eclipta prostrata (liver ailments), ivy gourd (diabetes), citron (hypertension), Centella asiatica (psychological ailments), spade nose shark (lactogogue), reticulate whipray (wheezing and bronchitis), Katelysia opima (impotence), Indian squid (anemia), and Indian oil sardine (anabolic). More studies on these claims will help identify novel functional foods to add to the field of medical nutrition therapy, with traditional brand identity. Robust studies on the documentation of the traditional knowledge on marine resources will yield a good database for various stakeholders and policy makers.

A role of Ficus species in the management of diabetes mellitus: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetes mellitus is one of the most common global health concerns, with a rapidly increasing incidence. A variety of medicinal plants, particularly those belonging to the genus Ficus (Moraceae), and their active compounds have been used to treat diabetes and related chronic disorders since ancient times.

AIM OF THE STUDY

The aim of this review is to provide information regarding traditional and scientific knowledge of Ficus species with antidiabetic activity to researchers.

MATERIALS AND METHODS

A literature search was conducted to obtain information about the antidiabetic properties of Ficus from the electronic databases. Common and scientific names of various Ficus species were used as keywords for the search, along with the terms antidiabetic, hypoglycemic and diabetes.

RESULTS

Among the assorted species of Ficus that were included in our search, F. benghalensis, F. carica, F. glomerata, F. glumosa, F. racemosa, and F. religiosa exhibited remarkable antidiabetic properties with various mechanisms of action. Moreover, Ficus species are versatile sources of bioactive metabolites such as flavonoids, phenolic acids, tannins, alkaloids, glycosides, coumarins, triterpenoids, sterols and vitamin E. These extracts and isolated compounds significantly have enhanced insulin secretion and subsequently reduced blood glucose level in various in vivo studies.

CONCLUSION

This review summarizes the antidiabetic potentials of the genus Ficus, including pharmacological studies with mechanisms of action as well as ethnobotanical uses. This review can help inform future scientific research towards the development of novel antidiabetic drugs.

Insecticidal activity of camphene, zerumbone and α-humulene from Cheilocostus speciosus rhizome essential oil against the Old-World bollworm, Helicoverpa armigera

The fast-growing resistance development to several synthetic and microbial insecticides currently marketed highlighted the pressing need to develop novel and eco-friendly pesticides. Among the latter, botanical ones are attracting high research interest due to their multiple mechanisms of action and reduced toxicity on non-target vertebrates. Helicoverpa armigera (Lepidoptera: Noctuidae) is a key polyphagous insect pest showing insecticide resistance to several synthetic molecules used for its control. Therefore, here we focused on the rhizome essential oil extracted from an overlooked Asian plant species, Cheilocostus speciosus (J. Konig) C. Specht (Costaceae), as a source of compounds showing ingestion toxicity against H. armigera third instar larvae, as well as ovicidal toxicity. In acute larvicidal assays conducted after 24h, the C. speciosus essential oil achieved a LC₅₀ value of 207.45µg/ml. GC and GC-MS analyses highlighted the presence of zerumbone (38.6%), α-humulene (14.5%) and camphene (9.3%) as the major compounds of the oil. Ingestion toxicity tests carried out testing these pure molecules showed LC₅₀ values of 10.64, 17.16 and 20.86µg/ml, for camphene, zerumbone and α-humulene, respectively. Moreover, EC₅₀ values calculated on H. armigera eggs were 35.39, 59.51 and 77.10µg/ml for camphene, zerumbone and α-humulene, respectively. Overall, this study represents the first report on the toxicity of C. speciosus essential oil against insect pests of agricultural and medical veterinary importance, highlighting that camphene, zerumbone and α-humulene have a promising potential as eco-friendly botanical insecticides.

A review of cinnabar (HgS) and/or realgar (As4S4)-containing traditional medicines

ETHNOPHARMOCOLOGICAL RELEVANCE

Herbo-metallic preparations have a long history in the treatment of diseases, and are still used today for refractory diseases, as adjuncts to standard therapy, or for economic reasons in developing countries.

AIM OF THE REVIEW

This review uses cinnabar (HgS) and realgar (As₄S₄) as mineral examples to discuss their occurrence, therapeutic use, pharmacology, toxicity in traditional medicine mixtures, and research perspectives.

MATERIALS AND METHODS

A literature search on cinnabar and realgar from PubMed, Chinese pharmacopeia, Google and other sources was carried out. Traditional medicines containing both cinnabar and realgar (An-Gong-Niu-Huang Wan, Hua-Feng-Dan); mainly cinnabar (Zhu-Sha-An-Shen Wan; Zuotai and Dangzuo), and mainly realgar (Huang-Dai Pian; Liu-Shen Wan; Niu-Huang-Jie-Du) are discussed.

RESULTS

Both cinnabar and realgar used in traditional medicines are subjected to special preparation procedures to remove impurities. Metals in these traditional medicines are in the sulfide forms which are different from environmental mercurials (HgCl₂, MeHg) or arsenicals (NaAsO₂, NaH₂AsO₄). Cinnabar and/or realgar are seldom used alone, but rather as mixtures with herbs and/or animal products in traditional medicines. Advanced technologies are now used to characterize these preparations. The bioaccessibility, absorption, distribution, metabolism and elimination of these herbo-metallic preparations are different from environmental metals. The rationale of including metals in traditional remedies and their interactions with drugs need to be justified. At higher therapeutic doses, balance of the benefits and risks is critical. Surveillance of patients using these herbo-metallic preparations is desired.

CONCLUSION

Chemical forms of mercury and arsenic are a major determinant of their disposition, efficacy and toxicity, and the use of total Hg and As alone for risk assessment of metals in traditional medicines is insufficient.

Phytotherapy in the Management of Diabetes: A Review

Phytotherapy has long been a source of medicinal products and over the years there have been many attempts to use herbal medicines for the treatment of diabetes. Several medicinal plants and their preparations have been demonstrated to act at key points of glucidic metabolism. The most common mechanisms of action found include the inhibition of α-glucosidase and of AGE formation, the increase of GLUT-4 and PPARs expression and antioxidant activity. Despite the large amount of literature available, the actual clinical effectiveness of medicinal plants in controlling diabetes-related symptoms remains controversial and there is a crucial need for stronger evidence-based data. In this review, an overview of the medicinal plants, which use in the management of diabetes is supported by authoritative monographs, is provided. References to some species which are currently under increasing clinical investigation are also reported.

Zuotai and HgS differ from HgCl2 and methyl mercury in Hg accumulation and toxicity in weanling and aged rats

Mercury sulfides are used in Ayurvedic medicines, Tibetan medicines, and Chinese medicines for thousands of years and are still used today. Cinnabar (α-HgS) and metacinnabar (β-HgS) are different from mercury chloride (HgCl₂) and methylmercury (MeHg) in their disposition and toxicity. Whether such scenario applies to weanling and aged animals is not known. To address this question, weanling (21d) and aged (450d) rats were orally given Zuotai (54% β-HgS, 30mg/kg), HgS (α-HgS, 30mg/kg), HgCl₂ (34.6mg/kg), or MeHg (MeHgCl, 3.2mg/kg) for 7days. Accumulation of Hg in kidney and liver, and the toxicity-sensitive gene expressions were examined. Animal body weight gain was decreased by HgCl₂ and to a lesser extent by MeHg, but unaltered after Zuotai and HgS. HgCl₂ and MeHg produced dramatic tissue Hg accumulation, increased kidney (kim-1 and Ngal) and liver (Ho-1) injury-sensitive gene expressions, but such changes are absent or mild after Zuotai and HgS. Aged rats were more susceptible than weanling rats to Hg toxicity. To examine roles of transporters in Hg accumulation, transporter gene expressions were examined. The expression of renal uptake transporters Oat1, Oct2, and Oatp4c1 and hepatic Oatp2 was decreased, while the expression of renal efflux transporter Mrp2, Mrp4 and Mdr1b was increased following HgCl₂ and MeHg, but unaffected by Zuotai and HgS. Thus, Zuotai and HgS differ from HgCl₂ and MeHg in producing tissue Hg accumulation and toxicity, and aged rats are more susceptible than weanling rats. Transporter expression could be adaptive means to reduce tissue Hg burden.