A first approach for the micropropagation of the medicinal halophyte Polygonum maritimum L. and phenolic profile of acclimatized plants

Efficient Micropropagation of Bistorta amplexicaulis (D.Don) Greene: An Important Medicinal Plant of Western Himalaya

Bistorta amplexicaulis (D.Don) Greene from the family Polygonaceae is an important medicinal plant species. The growing therapeutic use of B. amplexicaulis has led to its population depletion thus requiring its conservation. Herein, an efficient, reproducible and reliable propagation protocol system was established for B. amplexicaulis using nodal segments as explant. Various culture media were tested for the assessment of growth and development of this plant species. On the shoot proliferation and rhizogenesis of regenerated B. amplexicaulis plantlets, the effects of several plant growth regulators (PGRs) were assessed. Direct organogenesis from nodal segments was achieved by culturing the nodal explants on Murashige and Skoog medium supplemented with 2.0 mg·L-1 6-benzylaminopurine (BAP). Shoot multiplication was widely affected by the kind and concentration of PGRs, and the subculturing of in vitro regenerated shootlets on fresh medium. After incubation for 4 weeks at optimum BAP concentration, cultures were transferred to secondary medium with BAP (optimized concentration) supplemented with different auxins (indole acetic acid, indole butyric acid, and naphthalene acetic acid [NAA]). Murashige and Skoog medium enriched with 2.0 mg·L-1 BAP showed the highest shoot induction response (83% ± 3.61%) with mean shoot number (4.67 ± 1.45) and shoot length of 4.33 ± 1.45 cm. Growth medium fortified with 1.0 mg·L-1 α- NAA exhibited maximum rhizogenesis with 4.33 ± 0.88 roots and average root length as 5.50 ± 0.76 cm from regenerated B. amplexicaulis shoots. Acclimatized plants of B. amplexicaulis showed 90% survival. The projected protocol may serve as a treasured tool for the rapid and large-scale multiplication of elite B. amplexicaulis and for germplasm conservation to ensure continuous supply of this plant amid the increasing demand.

The genus Polygonum: An updated comprehensive review of its ethnomedicinal, phytochemical, pharmacological activities, toxicology, and phytopharmaceutical formulation

Polygonum is a plant genus that includes annual and perennial species and is found at various temperatures, from northern temperate regions to tropical and subtropical areas. The genus Polygonum has been used for centuries for various disorders, including hypertension, intestinal and stomach pain, dysuria, jaundice, toothaches, skin allergies, hemorrhoids, cardiac disorders, kidney stones, hemostasis, hyperglycemia, and others. Various databases, including Google Scholar, Scifinder, ScienceDirect, PubMed, Scopus, ResearchGate, and Web of Science, were utilized to collect pertinent scientific literature data. According to bibliographic studies, the Polygonum genus possesses various compounds from different families, including phenolic acids (gallic acid, caffeic acid, quinic acid, p-coumaric acid, ferulic acid, protocatechuic acid, chlorogenic acid, and many other compounds), flavonoids (quercetin, catechin, epicatechin, quercitrin, kaempferol, myricetin, etc.), tannins, stilbenes (polydatin and resveratrol), terpenes (α-pinene, β-caryophyllene and β-caryophyllene oxide, bisabolene, β-farnesene, etc.), fatty acids (decanoic acid, lauric acid, linoleic acid, oleic acid, palmitic acid, stearic acid, dodecanoic acid), polysaccharides, and others. Various chemical and biological activities (in vitro and in vivo), such as antioxidant, antimicrobial, anticancer, antitumor, anti-inflammatory, antidiabetic, antiparasitic, hepatoprotective, neuropharmacological, gastroprotective, diuretic, antipyretic, and others, have been described in several biological studies involving this species. An updated summary of Polygonum species and their ethnomedicinal, phytochemical, toxicological, pharmacological, and phytopharmaceutical formulations is necessary. Considering the numerous potentialities of the Polygonum species and their wide-ranging use, it is extremely essential to provide knowledge by compiling the accessible literature to identify the topics of intense investigation and the main gaps to better design future studies. The objective of this review is to give readers a better understanding, greater comprehension, and in-depth knowledge of the genus Polygonum's traditional applications, phytochemistry, pharmacology, toxicological features, and galenic formulation. Several species of this genus have been detailed in this review, including those that were frequently used in traditional medicine (P. minus, P. aviculare, P. hydropiper, P. cuspidatum, and P. multiflorum) and many of the genus' therapeutic species, like P. equisetiforme, which do not get enough attention.

Temporary Immersion Bioreactors for Sugarcane Multiplication and Rooting

Sugarcane is used to produce sugar, ethanol, and other by-products, so it is considered one of the most important crops worldwide. Using temporary immersion systems for sugarcane micropropagation represents an alternative to reduce the labor force, increase plant development, and improve plant quality. Temporary immersion systems are semi-automated bioreactors designed for the large-scale propagation of tissues, embryos, and organs. These are temporarily exposed in a liquid culture medium under a specific time and immersion frequency. Using this protocol and a temporary immersion bioreactor, it is possible to achieve multiplication and rooting. The use of temporary immersion bioreactors improves the multiplication rate and the rooting of sugarcane, reducing the culture time, labor force, and reagents needed while maintaining high survival rates during acclimatization.

Application of In Vitro Plant Tissue Culture Techniques to Halophyte Species: A Review

Halophytes are plants able to thrive in environments characterized by severe abiotic conditions, including high salinity and high light intensity, drought/flooding, and temperature fluctuations. Several species have ethnomedicinal uses, and some are currently explored as sources of food and cosmetic ingredients. Halophytes are considered important alternative cash crops to be used in sustainable saline production systems, due to their ability to grow in saline conditions where conventional glycophyte crops cannot, such as salt-affected soils and saline irrigation water. In vitro plant tissue culture (PTC) techniques have greatly contributed to industry and agriculture in the last century by exploiting the economic potential of several commercial crop plants. The application of PTC to selected halophyte species can thus contribute for developing innovative production systems and obtaining halophyte-based bioactive products. This work aimed to put together and review for the first time the most relevant information on the application of PTC to halophytes. Several protocols were established for the micropropagation of different species. Various explant types have been used as starting materials (e.g., basal shoots and nodes, cotyledons, epicotyls, inflorescence, internodal segments, leaves, roots, rhizomes, stems, shoot tips, or zygotic embryos), involving different micropropagation techniques (e.g., node culture, direct or indirect shoot neoformation, caulogenesis, somatic embryogenesis, rooting, acclimatization, germplasm conservation and cryopreservation, and callogenesis and cell suspension cultures). In vitro systems were also used to study physiological, biochemical, and molecular processes in halophytes, such as functional and salt-tolerance studies. Thus, the application of PTC to halophytes may be used to improve their controlled multiplication and the selection of desired traits for the in vitro production of plants enriched in nutritional and functional components, as well as for the study of their resistance to salt stress.