Genus Dioscorea Research Articles

Propagation and molecular analysis in Dioscorea: a bibliometric review

Species of the genus Dioscorea, popularly called yams, are notable primarily for their nutritional value and the production of bioactive compounds. Considering the importance of this genus for the food and pharmaceutical industries, the present study aimed to understand the state of the art in the area of propagation and molecular characterization of the genus, based on bibliometric analysis. Bibliometrics was the basic methodological tool used, and the data were sourced from the Scopus® and Web of ScienceTM databases. A total of 69 publications on the propagation of the Dioscorea genus were analyzed. The average number of publications per year was 4.69, with the highest number of publications observed in 2011 and an annual growth rate of 4.25%. The most developed themes were those related to propagation through in vitro cultivation. Regarding molecular characterization, 44 publications were analyzed. The average number of publications was 5.37, with the highest number of publications observed in 2017 and an annual growth rate of 7.11%. The most important themes were related to the genetic diversity of species of the genus. This review maps the existing studies and identifies gaps in the research field on the propagation and molecular characterization of species of the genus Dioscorea.

A Frontier Review of Nutraceutical Chinese Yam.

Yams are the edible subterranean rhizomes, or tubers, of plants from the genus Dioscorea. There are approximately 600 species of yam plants in the world, with more than 90 of these growing in East Asia. One particular species, Dioscorea opposita Thunb., is highly praised as "the Chinese yam". This distinction arises from millennia of storied history, both as a nutritional food source and as a principal ingredient in traditional Chinese medicine. Among the many cultivars of Dioscorea opposita Thunb., Huai Shanyao has been widely regarded as the best. This review surveyed the historical background, physiochemical composition, applications as food and medicine, and research prospects for the Chinese yam. Modern science is finally beginning to confirm the remarkable health benefits of this yam plant, long-known to the Chinese people. Chinese yam promises anti-diabetic, anti-oxidative, anti-inflammatory, immunomodulatory, anti-hyperlipidemic, anti-hypertensive, anti-cancer, and combination treatment applications, both as a functional food and as medicine.

The diversity, ethnobotany and nutrient contents of Dioscorea for post-disaster food security in Lombok, Indonesia

Abstract. Indriyatno, Wijayanto N, Batubara I, Supriyanto. 2024. The diversity, ethnobotany and nutrient contents of Dioscorea for post-disaster food security in Lombok, Indonesia. Biodiversitas 25: 553-564. Earthquakes caused damage to infrastructure, houses, and roads in Lombok in 2018. After the earthquake, there was a shortage of food. Adaptation to address food shortage can be overcome by using local food sources, including those from the Dioscorea genus. The study aims to analyze the diversity and distribution, ethnobotany and nutrient contents of the Dioscorea genus in Lombok Island. Botanical explorations were conducted to identify the intraspecific varieties in the form of local types/names complemented with ethnobotanical study through structured interviews. The nutrient contents were determined using a standardized method in proximate analysis. The study found 12 local types of Dioscorea belonging to four species which are used by the community for adaptation after earthquake disaster, namely: D. bulbifera (kentang), D. bulbifera (engal), D. alata (uwi sawa), D. alata (lami), D. alata (uwi kuning ampenan), D. alata (uwi putih ampenan), D. alata (uwi ungu dara kunci), D. alata (uwi putih batu layar), D. alata (uwi ungu batu layar), D. esculenta var. apiculata (surak), D. esculenta var. spinosa (gembili) and D. pentaphylla (buyut). The highest diversity of Dioscorea is found in climate type C3 (8 local types), followed by climate type E (5 local types), climate type D4 (4 local types), climate type B2 (3 local types), and climate type C2 and D3 (1 local type). The local community utilizes the Dioscorea genus in several cultural events including when celebrating the Prophet Muhammad's birthday. The nutritional value of Dioscorea genus is high due to its carbohydrate content (66,09-76,96%), protein content (3.79­-10.84%), fat content (1.70-9.58 %) and fiber content (0.32-6.81%). This study shows the potential of Dioscorea to be used as food sources that are cheap, easy to grow, and more adaptive to different environmental conditions to help post-earthquake communities.

Pollen variability in species of Dioscorea L. (Dioscoreaceae)

Dioscoreaceae is characterised by wide morphological variability, including hermaphrodite genera such as Tacca J.R.Forst. et G.Forst, Trichopus Gaertn., and Stenomeris Planch. and some dioecious species in the genus Dioscorea L. This study aimed to describe the pollen characters of 81 species of Dioscorea occurring in Brazil, contributing to a broader knowledge of Dioscoreaceae by investigating the possibility of using pollen attributes in taxonomic classification. Pollen grains were treated by lactic acetolysis, measured, described, and photomicrographed. The results were subjected to statistical analysis. Unacetolysed pollen grains were mounted on stubs with carbon tape for scanning electron microscopy. Our results showed that the studied species have heteropolar pollen grains, ranging from small to medium, with mainly elliptical, circular, and triangular ambs. Pollen grains with 1, 2, or 1‒2 apertures were recorded in most species, as well as nine types of sexine ornamentation (perforate in 23 species, striate in 23 species, microreticulate in 15 species, reticulate in eight species, rugulate in seven species, bireticulate in two species, rugulate-verrucate in one species, cristate in one species, and gemmate in one species). The sexine had striae in different shapes and directions. Micromorphological results of pollen characters were of great importance for species delimitation. The findings reported herein demonstrate that palynological analysis can provide valuable information to improve taxonomic classification and contribute to a more robust phylogenetic representation of the genus.

Genome Survey Sequencing of the Medical Plant Dioscorea futschauensis: Genomic Characteristics Estimation and Genomic Resources Development

Dioscorea futschauensis Uline ex R. Knuth, a perennial climbing herb belonging to the Stenophora section of the genus Dioscorea L. (Dioscoreaceae), originates from Southeast China and is highly regarded for its medicinal properties. Despite its medicinal significance, the absence of genomic information has impeded the effective utilization and conservation of this species. Here, we conducted genome survey sequencing of D. futschauensis to unveil its genomic characteristics and identify species-specific genomic markers, including whole plastome sequence, plastome-divergent hotspots, single-copy nuclear genes and polymorphic nuclear SSRs. The genome of D. futschauensis was approximated to be 1392.76 Mb in length, accompanied by a substantial heterozygosity rate of 1.75% and a repeat content of 67.43%. Comparative plastome analysis illuminated the conserved genome structure and gene content within D. futschauensis, and revealed four highly divergent hotspots (atpF intron, psbA-matK, matK -rps16, and rrn16-trnI) that could serve as molecular markers for D. futschauensis and its closely related species. Furthermore, more than 200 single-copy nuclear genes and 78 polymorphic nuclear SSRs were identified within D. futschauensis. Overall, the comprehensive genomic information and abundant genetic resources provided herein will not only facilitate extended research in the realms of population genetics, phylogenetics and conservation biology of D. futschauensis, but also hold considerable value for its cultivation and molecular breeding applications.

Geographic distribution and uses of species of the genus Dioscorea

Species of the genus Dioscorea are widely distributed throughout the world. It is a resource used in different countries because theyproduce tubers that offer numerous benefits for human health due to their diosgenin content, a compound that is used as: anti-inflammatory, androgenic, estrogenic and in the preparation of contraceptive drugs; It is also mentioned that these compounds havecytotoxic, antitumor, antifungal, immunoregulatory, hypoglycemic and cardiovascular properties, they are also used for theprevention and treatment of degenerative diseases. Species such as Dioscorea bulbifera, Dioscorea cayenensis, Dioscorea colletii,Dioscorea deltoidea, Dioscorea futschauensis, Dioscorea nipponica, Dioscorea panthaica, Dioscorea parviflora, Dioscoreapolygonoides, Dioscorea pseudojaponica, Dioscorea spongiosa, Dioscorea villosa, Dioscorea composita, Dioscorea zingiberensis,produce a higher concentration of diosgenin. The tubers and roots of this group are part of the oldest foods consumed by humans,given their high nutritional, ecological and economic level. In many tropical countries, the use of various tubers and roots of thegenus Dioscorea play a very important role as a main source of energy and essential nutrients at low cost, they are also used asfodder for livestock and a source of income. This plant are rich in starch, vitamins, minerals and lipids, and have the potential tofight hunger in third world countries. Currently there is little or no knowledge in Mexico on how to cultivate these species.

The Utilization of Dioscorea Tuber in Self-Rising Starch: a Review

Self-rising starch is a development product of self-rising flour. This product minimizes the process, especially in the salt and leavening agent weighing stage, so that it reduces the time in the serving process. Self-rising flour is generally made of wheat flour. Currently, due to some medical considerations, many people cannot consume this product. Based on some research results, gluten compound in wheat flour or wheat triggers for the development of type-1 diabetes. This fact has caused Indonesia to be ranked fifth in the world for the diabetic diseases. Thus, one of the ways to overcome this problem is by utilizing the raw materials originating from Indonesia too, namely tubers. Indonesia has a variety of tubers. Some of these tubers, however, have not been explored. These tubers have not only the function as the good sources of carbohydrates but also the bioactive compounds and more functional values, such as water soluble polysaccharides (WSP), diosgenin, inulin and glycemic index. They increase the functional properties of the starch that are produced. The tubers that currently have not been cultivated are the genus Dioscorea. The various tubers that are included in dioscorea family are uwi, gembili, gadung, tomberoso and jebubuk. All of these tubers are good sources of carbohydrates. Uwi, gembili and gadung are tubers that have been cultivated by the people for many years. On the hand, tomberoso and jebubuk tubers grow wildly in the forest that only become the foods for the wild animals in it. The starch derived from the disccorea tubers can be used as self-rising starch because it has the property as food developer. It contains high carbohydrates and bio-active compound, therefore, it is healthier to consume.

Development and Validation of Quantitative Analysis Method for Phenanthrenes in Peels of the Dioscorea Genus.

Phenanthrenes are bioactive phenolic compounds found in genus Dioscorea, in which they are distributed more in peel than in flesh. Recent studies on phenanthrenes from Dioscorea sp. peels have revealed the potential for valuable biomaterials. Herein, an analytical method using high-performance liquid chromatography (HPLC) for quantitation of bioactive phenanthrenes was developed and validated. The calibration curves were obtained using the phenanthrenes (1-3) previously isolated from Dioscorea batatas concentrations in the range of 0.625-20.00 μg/ml with a satisfactory coefficient of determination (R2) of 0.999. The limit of detection (LOD) and the limit of quantification (LOQ) values of the isolated phenanthrenes ranged from 0.78-0.89 and 2.38-2.71 μg/ml, respectively. The intraday and interday precision ranged from 0.25-7.58%. The recoveries of the isolated phenanthrenes were from 95 to 100% at concentrations of 1.25, 2.5, and 5.0 μg/ml. Additionally, phenanthrenes (1-3) were found in all investigated peel extracts. Hence, the developed method was encouraging for the quantitative analysis of phenanthrenes in genus Dioscorea.

Evolution of Reproductive Traits and Implications for Adaptation and Diversification in the Yam Genus Dioscorea L.

Dioscorea is a pantropical monocotyledonous genus encompassing several well-known tuber crops and medicinal plants. It possesses remarkable morphological diversity, especially in reproductive characteristics, which are suggested to play important roles in species adaptation and diversification. Yet there have been few studies that consider the evolutionary pattern followed by these characters in this genus. In this study, the phylogenetic relationships among Chinese yams were reconstructed from five chloroplast and two mitochondrial DNA sequences. The evolutionary histories of bulbil possession, inflorescence architecture, the color of the male flowers and the degree of male flower opening were reconstructed. The results suggested that yam bulbils evolved after the divergence between D. sect. Testudinaria and other species of Dioscorea except for in D. sect. Stenophora and D. sect. Apodostemon. The evolutionary trend in the degree of male flower opening ranged from fully open to nearly closed. Male flowers with dark colors and panicles were shown to be derived in Dioscorea. These characteristics were found to be closely associated with the reproductive patterns and pollinating mechanisms of the Dioscorea species. The findings also shed light on the systematic relationships within this genus.

A palynological study of Dioscorea (Dioscoreaceae) in Korea

A palynological study of genus Dioscorea L. in Korea was conducted to evaluate the taxonomic implications. As a result of confirming the palynological characteristics of seven taxa of Dioscorea L., including six that are distributed in Korea and D. tokoro found in Japan, sections or species were classified according to the characteristics, such as the number of apertures, the polar end shape, and exine sculpturing. Specifically, the exine sculptures of D. coreana and D. tokoro, erroneously known to be distributed in Korea, are distinguished. The change in the number of apertures is closely associated with microsporogenesis, and it can be presumed that disulcate pollen might have been derived from monosulcate pollen in Dioscorea.

Typification of nine names of Asian species and varieties of Dioscorea (Dioscoreaceae)

AbstractThe yam genus Dioscorea includes some of the world's most important food and medicinal plants The names of most Asian species and infraspecific taxa are in need of typification because their publication predated the 1935 Cambridge Rules of Botanical Nomenclature in which the concept of nomenclatural types was first introduced. Here, the Dioscorea collections cited in the protologues and uncited material associated with the names at their first publications are evaluated in the light of the latest Shenzhen Code (2018) and lectotypes of eight names designated, viz. D. lepcharum, D. nummularia var. glauca, D. pentaphylla var. communis, D. pentaphylla var. linnaei, D. pentaphylla var. malaica, D. pentaphylla var. rheedei, D. pentaphylla var. thwaitesii and D. rogersii. Most of the original materials concerned were collected from India, and the rest from other parts of South Asia and South East Asia (Bangladesh, Sri Lanka, Philippines and Malaysia). The single specimen cited in the protologue of D. wightii Hook.f. is affirmed here as the holotype.

Dioscorea genus: A Possible Ally in the Sectors of Agriculture, Food Security and as a Source of Inputs for the Pharmaceutical Industry

Dioscorea genus: A Possible Ally in the Sectors of Agriculture, Food Security and as a Source of Inputs for the Pharmaceutical Industry

Comparison of nutrient composition of wild Dioscorea species consumed by ethnic groups of Odisha in India with commercially cultivated roots and tubers

This study was carried out to analyze the nutrient composition of wild tubers belonging to Dioscorea genus of the Dioscoreaceae family consumed by the ethnic groups in the Jeypore District of Koraput region in Odisha, India. The collected tubers are significant storehouses of energy and nutrition and also, they are known to produce large quantities of energy in relatively less time than the other crops. We have selected six wild species of Dioscorea collected from Odisha among the twenty-six reported species of India, along with five locally available cultivated tuber varieties of different genera from Tamil Nadu markets for comparison. The objective of this study is to understand the major source of nutrition of the ethnic groups, who consume local plant varieties collected from the wild and also to compare them with that of commercially available cultivated varieties in the view of the prevailing biodiversity and the varied agro-climatic conditions in India.

CHROMOSOMAL ANALYSIS OF EIGHT CULTIVARS IN THREE SPECIES OF CULTIVATED YAM (DIOSCOREA) SPECIES IN NIGERIA

The genus Dioscorea comprises of economically-important plant species known for their starch throughout the world; it is also a major source of food and income in Africa. The most important Dioscorea species cultivated and consumed in the West Africa belt include D. cayenensis, D. rotundata and D. alata. The plant materials used in this study were collected from Omu-Ekiti, Oye Local Government of Ekiti State, Nigeria using the On Farm Participatory Method (OFPM). Mitotic chromosome studies were carried out on three species viz, Dioscorea alata (‘ewura’), D. cayenensis (‘igangan’) and D. rotundata (‘areyingbakumo’, ‘gaungaun’, ‘ikumo’, ‘ogunmole’ and ‘sandpaper’). Mitotic chromosome studies were carried out on each of the cultivars using the root tip squash method made in modified Orcein stain (FLP-Orcein). Dormant tubers were cut to mini-setts and placed in carbonised rice husk for rooting. This study reports the basic chromosome number of x = 8, i.e. 2n = 4x =32 (D. alata), 2n = 4x =38 (D. rotundata) and 2n = 8x = 68 (D. cayenensis) for Dioscorea suggesting that both D. rotundata and D. cayenensis are aneuploids.

The Unique Substance, Lidocaine and Biological Activity of the Dioscorea Species for Potential Application as a Cancer Treatment, Natural Pesticide and Product

The six Dioscorea species, D. brevipetiolata, D. bulbifera, D. depauperata (Dd), D. glabra (Dg), D. pyrifolia and D. hamiltonii were analyzed for phytochemicals, toxicity in PBMCs, and biological activity in two cancer cell lines by MTT and comet assays, and pesticide efficiency. Via GC-MS, lidocaine was found to be the predominant compound in two of the studied species. To confirm the systematics, lidocaine was also found in lower amounts in 11 species. The MTT assay showed no toxicity in all six of the studied species. The comet assay showed the key result that the ethanol extracts of Dd and Dg violently broke DNA into pieces. Biological activity of these two species’ extracts showed toxicity on HepG2 and no effects on HCT-116. The water extracts of Dd and Dg, applied to Brassica chinensis showed high efficiency as a bioprotectant. In summary, lidocaine seems to be the predominant identifying compound of the genus Dioscorea in Thailand, which is useful in systematics. At least the two species, Dd and Dg, may be used for human hepatocyte cancer treatment and as an alternative pesticide for economically important vegetables. Dioscorea species containing lidocaine or extracted lidocaine have promise for natural product creation.

A Review Article on Pharmacologic Evaluation, Botanical report and Calming uses of Dioscorea bulbifera Linn. and Dioscorea pentaphylla Linn.

The present-day investigation focuses on the Pharmacologic revision of the climbers of D. bulbifera L &. D. pentaphylla L. (Dioscoreaceae). Climbers have been deliberate from diverse angles of morphological and, residue scrutiny, and extractive standards. Morphological analysis discovered nature, dimensions, aroma and flavour of tubers. The genus Dioscorea have its place to the family Dioscoreaceae, universally recognized as yam, consist of nearly 600 sps. Scattered all over the earth realm, but customarily in steamy section. Most sps. encompass steroid saponins and correspondingly sapogenins, such as diosgenin, which is preparatory quantifiable for blend of various steroidal hormones castoff as anti-inflammatory, androgenic estrogenic and contraceptive drugs. Associates of the genre Dioscorea are one of ancient tuber crop cultured or garnered from uninhabited in steamy constituency all over earth realm and set up one of the key food element for various indigenous groups. Genus is reflected to be amid the most primeval angiosperms and was recognized to occur and broaden the horizons nearly 75 M. Yrs. past in segments of southern celestial-sphere at the termination of the cretaceous period

Physiological and biochemical evaluation of <i>Dioscorea alata L.</i> tubes cultivated on a modified ion-exchange substrate

Relevance. Currently, there is an increased interest in medicinal plants and preparations from natural herbal raw materials. This is due to the fact that biologically active substances of plants are more easily included in vital processes and do not cause side effects in humans. They can be products of primary (vitamins, fats, carbohydrates, proteins) and secondary biosynthesis (alkaloids, glycosides, tannins). Plants always contain a complex of biologically active substances, but one or several have a therapeutic and prophylactic effect. They are classified as active ingredients and are used in the production of medicines. Some of the promising medicinal plants are species from the genus Dioscorea, for example, Dioscorea alata L., containing a complex of biologically active substances. The aim of this work is to study the effect of humidity and the level of mineral nutrition in the root environment on the accumulation of biologically active compounds in the tubers of the dioscorea winged plant, adapted to in vivo conditions on an ion-exchange substrate of various chemical composition and agrophysical properties.Results. It has been shown that Dioscorea alata L. plants are able to accumulate the greatest amount of starch, dry matter, ascorbic acid, and flavonoids in an ion-exchange substrate modified with 1 g/l of the coarse hydrogel fraction. The data obtained can be used for practical purposes.

Caryatin and 3’-O-methylcaryatin contents in edible yams (Dioscorea spp.)

The genus Dioscorea hosts a large number of yam species used medicinally and as a staple food by millions of people in tropical countries. All yams share a high antioxidant activity that correlates with their total phenolics contents. However, knowledge of edible species antioxidant phenolics remains incomplete. Bioassay-guided fractionation of the tubers of a yam species with high total phenolics content, D. nummularia, led to the isolation of two flavonols, caryatin and 3′-O-methyl caryatin, contributing over 92% of a stable methanol extract of the tuber in this species. Their structures were determined by high resolution mass spectrometry (HRMS), nuclear magnetic resonance (NMR) and a synthesized authentic sample. They displayed no bacterial toxicity. Their content was estimated in the tubers and bulbils of 411 landraces and hybrids belonging to eight food yam species using high performance-thin layer chromatography (HP-TLC). These were found to be highly variable at the intra- and interspecific levels to reach up to 1 030 and 457 μg/g DW respectively and added up to contents of already described antioxidant phenolics. This study provides additional understanding of the health benefits of a yam diet and constitutes the first phytochemical analysis of D. nummularia.

Medicinal uses of few edible tuber crops by“Dongria Kandha” tribes of Kandhamal district of Odisha, India

This paper describes the systematic study of root and tuber crops consumed by “Dongria Kandha” tribes of two blocks of “Kandhamal” district of Odisha. Periodic surveys were conducted in 25 villages of these two blocks regarding the methods of uses of different wild and cultivated edible tuber crops. Total seven types of edible tuber crops were consumed by this tribe. As no specific reports are available on the tuber crops consumed as food and medicine by this tribe, therefore documentation of tuber crops relating to the methods of uses, along with the morphological parameters were recorded. During survey 10 species of Dioscorea genus were found to be consumed as food as well as medicine to cure various ailments. Among them two species were found to be bitter in taste and unpalatable when consumed raw. Various methods were applied by the tribes to make the tubers palatable. The methods of consumption of ten species of Dioscorea along with the medicinal uses to treat various diseases were described in this article. Therefore these crops are valued for food security and also play a vital role towards diminishing rural poverty as well as have significant contribution towards curing of various diseases.

Effect of various drying methods on the physical characteristics of purple yam powder

Purple yam (Dioscorea alata) is a type of plant that grown in almost all regions of Southeast Asia. In Indonesia, purple yam is one of the most popular types of sweet potatoes compared to other types of the genus Dioscorea. Purple yum is usually consumed directly as a side dish, or processed into a powder. One important process of making purple yam powder is drying. In this study, the characteristics of purple yam powder were evaluated from several drying methods, namely sunlight drying (SD), cabinet drying (CD), and pneumatic drying (PD). The pneumatic dryer used was self-made with a stainless steel plate (3 mm thickness) and has total dimension of 1600x 500x 2500 mm. The results showed that the CD sample had the lowest water content. The purple yam powder by CD and PD can produce brighter powder compared to that with SD method. From the FM test, the smallest FM value was obtained from CD sample. CD sample proven to be able to retain purple yam nutritive values after drying process.