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Medicinal plants are an integral part of traditional medicine systems all over the world. Nepal, rich in biodiversity and ethnic, linguistic, and cultural diversity, possesses different traditional and folk medicinal practices for thousands of years. These systems have been using many locally available medicinal plants as crude drugs, which are not always properly documented. Detailed documentation and research related to the conservation and cultivation of medicinal plants should be carried out. Scientific studies related to chemical analysis, standardization, evaluation of pharmacological activities, and safety should be carried out to strengthen these systems of traditional medicine. Adequately designed clinical studies are necessary to provide evidence for their therapeutic efficacy

Fruits of Terminalia chebula Retz. (Combretaceae) are widely used as crude drugs in various traditional medicine systems. The aim of this article is to review the available scientific information regarding the traditional uses, bioactive chemical constituents and the pharmacological activities of T. chebula. Numerous researches conducted on T. chebula have confirmed the presence of wide range of the phytochemicals such as flavonoids, tannins, phenolic acids and other bioactive compounds. T. chebula is also widely studied regarding its pharmacological activities such as antioxidant, hepatoprotective, neuroprotective, cytotoxic, antidiabetic, anti-inflammatory activities among others. However, more in vivo and clinical studies for mechanism-based pharmacological evaluation should be conducted in future to provide stronger scientific evidences for their traditional uses.

The genus Zingiber consists of about 85 species and many of these species are used as food, spices, and medicines. One of the species, Zingiber montanum (J. Koenig) Link ex A. Dietr. is native to Southeast Asia and has been extensively used as traditional medicines and food. The aim of this review was to collect and critically analyze the scientific information about the bioactive compounds and pharmacological activities of Z. montanum with focus on one of the main components, zerumbone (ZER). Various studies have reported the analysis of volatile constituents of the essential oils from Z. montanum. Similarly, many phenylbutanoids, flavonoids and terpenes were also isolated from rhizomes. These essential oils, extracts and compounds showed potent antimicrobial, anti-inflammatory and antioxidant activities among others. Zerumbone has been studied widely for its anticancer, anti-inflammatory, and other pharmacological activities. Future studies should focus on the exploration of various pharmacological activities of other compounds including phenylbutanoids and flavonoids. Bioassay guided isolation may result in the separation of other active components from the extracts. Z. montanum could be a promising source for the development of pharmaceutical products and functional foods.

Background:Cocculus hirsutus (L.) W.Theob. (Menispermaceae) is a perennial climber distributed mostly in tropical and subtropical areas. The main aim of this article is to collect and analyze the scientific information related to traditional uses, bioactive chemical constituents and pharmacological activities. Methods: Scientific information on C. hirsutus was retrieved from the online bibliographic databases (e.g. MEDLINE/PubMed, SciFinder, Web of Science, Google Scholar and Scopus). Information regarding traditional uses was also acquired from secondary resources including books and proceedings. Results: Different plant parts of C. hirsutus were reported to be used for the treatment of fever, skin diseases, stomach disorders and urinary diseases. Alkaloids such as jasminitine, hirsutine, cohirsitine and their derivatives along with a few flavonoids, triterpene derivatives and volatile compounds were reported from whole plant or different plant parts. Extracts were evaluated for their antimicrobial, antidiabetic, immunomodulatory and hepatoprotective activities among others. Conclusion: Although widely used in traditional medicines, only a few studies have been performed related to chemical constituents. Most of the biological activity evaluations were carried out using in vitro evaluation methods and only a few studies were carried out in animal models. In the future, properly designed in vivo and clinical studies are necessary to evaluate the pharmacological activities of C. hirsutus along with bioassay-guided studies to isolate and identify the active constituents.

Ethnopharmacological relevance Blepharis is an Afro-Asiatic genus belonging to the family Acanthaceae. It comprises about 126 species that occur in arid and semi-arid habitats. Some species of Blepharis are used in traditional medicines in different countries mainly for their anti-inflammatory, wound healing activities along with treatment of gastrointestinal disorders and bone fractures. Aim of the review The present review aims to collate and analyze the available data and information on distribution, traditional uses, chemical constituents and pharmacological activities of Blepharis. Methods Scientific information of genus Blepharis was retrieved from the online bibliographic databases such as MEDLINE/PubMed, SciFinder, Web of Science and Google Scholar and secondary resources including books and proceedings. Results Seven species of Blepharis were found to be reported frequently as useful in folklore in African and Asian countries. B. maderaspatensis was found to be widely used in Indian traditional medicines whereas the B. ciliaris and B. edulis were common in folklore of Egypt, Jordan, and Arabia. Active phytochemicals of Blepharis are flavonoids from B. ciliaris, alkaloids from B. sindica, phenolic acid derivatives, and phytosterols, and derivatives of hydroxamic acids from B. edulis resulted in possessing diverse biological properties such as anti-microbial, anti-inflammatory, and anti-cancer. Conclusions Various species of Blepharis were found to be used in traditional medicine systems in African and Asian countries. Few of these species were studied for their bioactive chemical constituents however the activity guided isolation studies are not performed. Similarly, detailed pharmacological studies in animal models to explore their mechanism of action are also not reported. Future studies should focus on these aspects related to the medicinally used species of Blepharis. The detailed and comprehensive comparative analysis presented here gives valuable information of the currently used Blepharis species and pave the way to investigate other useful species of Blepharis pertaining to ethnobotany, phytochemistry and discovery of new drugs.

The flowering buds of Syzygium aromaticum (L.) Merr. & L.M.Perry. (synonym: Eugenia caryophyllata Thunb.; family: Myrtaceae), commonly known as clove, are widely used as a spice all over the world for the strong aromatic smell. Clove oil is a popular remedy for toothache due to its potent antiseptic and analgesic activity. It also has strong antioxidant and antiviral activities. Eugenol is the main component of clove oil. The lipid profiles, the contents of tocols, and total phenolics in cold pressed clove oil are well documented. Cold pressed clove oil was reported to possess stronger radical scavenging and antimicrobial activity compared to virgin oil. Similarly, the cold pressed clove oil was also reported to possess hepatoprotective activity in experimental animals along with other biological activities. This chapter covers the chemical and biological properties of cold pressed clove oil. Future studies should focus on the comparison of the activities of cold pressed oil with other oils using advanced methods, and the relationship between their activity and the chemical composition should be studied in detail.

The hydroalcoholic extract of leaves and twigs of Lindera neesiana (Wall. ex Nees) Kurz (Lauraceae) was subjected to various column chromatographic methods that isolated five kaempferol glycosides: kaempferol 3-O-&beta, glucopyranosyl(1&rarr, 2)-[&alpha, rhamnopyranosyl-(1&rarr, 6)]-&beta, glucopyranoside-7-O-&alpha, rhamnopyranoside (1), kaempferol 3-O-&beta, glucopyranosyl-(1&rarr, rhamnopyranosyl (1&rarr, glucopyranoside (2), 2)- &alpha, rhamnopyranoside-7-O-&alpha, rhamnopyranoside (3), kaempferol 3-O-sophoroside (4), and kaempferol 3-O-&alpha, rhamnopyranoside (5). The extract showed moderate free radical scavenging activity and potent pancreatic lipase inhibitory activity.

Background : The leaves and twigs of Lindera sericea (Seibold et Zucc.) Blume var. sericea (Lauraceae) are used as traditional medicines for treating indigestion, stomachache, anxiety, etc. In recent years, there has been a growing interest in these plant materials as a source of healthy drinks and functional foods. The main aim of this study was to characterize the major phenolic compounds from the leaves and twigs and to evaluate their free radical scavenging and α -glucosidase inhibitory activities. Methods : The dried leaves and twigs were extracted with 70% methanol. The dried extract was then subjected to repeated column chromatography to isolate eight flavonoids. The compounds were then evaluated for their 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and α -glucosidase inhibitory activity. Results : The isolated compounds were identified as (-)-epicatechin ( 1 ), taxifolin 3- O -glucoside ( 2 ), quercetin ( 3 ), quercitrin ( 4 ), quercetin 3- O -neohesperidoside ( 5 ), pinocembrin ( 6 ), pinostrobin ( 7 ) and pinostrobin chalcone ( 8 ) based on their nuclear magnetic resonance (NMR), spectroscopic data and comparison with literature values. All these compounds were isolated for the first time from this plant. All flavonoids except pinocembrin ( 6 ), pinostrobin ( 7 ) and pinostrobin chalcone ( 8 ) showed potent free radical scavenging activity. In α -glucosidase inhibitory activity assay, quercetin ( 4 ), quercitrin ( 5 ) and taxifolin 3- O -glucoside ( 2 ) showed potent activity. Conclusions: Eight flavonoids were reported for the first time from the leaves and twigs of the title plant. Some of these compounds showed potent free radical scavenging and α -glucosidase inhibitory activities. Keywords: Lindera sericea var. sericea ; Lauraceae; Kekuromoji; free radical; α-glucosidase

Chronic neuroinflammation is reported to be associated in the progression of many neurodegenerative diseases and there is an increasing interest for the natural products as neuroprotective and anti-neuroinflammatory agents. In present research, we evaluated the potential inhibitory effects of extract, fractions, and isolated compounds from Citrus 'Hebesu' on lipopolysaccharide (LPS)-induced inflammatory responses using BV-2 murine microglial cells. The dried methanol extract (CH) was suspended in water and partitioned with hexane and ethyl acetate to give hexane soluble (CHH), ethyl acetate soluble (CHE), and water soluble (CHW) fractions. The extract (CH) and fractions CHH and CHE inhibited the expression of mRNA encoding pro-inflammatory cytokine interleukin (IL)-1β. CHE and CHH were further purified by various column chromatographic methods to obtain hesperidin (1), tangeretin (2), 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone (3), 3,5,6,7,8,3',4'-heptamethoxyflavone (4), nobiletin (5), 3,4,5-trimethoxy-trans-cinnamic alcohol (6), and meranzin hydrate (7). Among them, three polymethoxyflavonoids, 3, 4, and 5 significantly inhibited the expression of IL-1β mRNA. PRACTICAL APPLICATIONS: Citrus 'Hebesu' is a local cultivar in Hyuga City, Miyazaki prefecture, Japan and its immature fruits are consumed with different food recipes. Till now, there is no detailed study on the chemical constituents and anti-neuroinflammatory activity of this cultivar. In this study, seven compounds were isolated from the peels of immature fruits. Methanol extract, hexane, and ethyl acetate fractions and three polymethoxyflavonoids showed a significant inhibitory activity against expression of IL-1β mRNA. Consumption of peels of Citrus 'Hebesu' might play important role in the prevention and treatment of neurodegenerative diseases, however, detailed mechanism based in vivo studies are necessary in future for providing more scientific evidences.

Flowers of Citrus plants are used as mild sedatives and for the treatment of insomnia in traditional medicines. In Japan, tea made from the flowers of Satsuma mandarin is consumed as healthy drink. Hesperidin (1), hesperetin (2), rutin (3), quercetin (4), nicotiflorin (5), eriocitrin (6), narirutin (7), phenylethyl glucoside (8) and unshuoside A (9) were isolated from the MeOH extract of fresh flowers. Structure elucidation of these compounds was performed on the basis of NMR spectroscopic data. Among them, rutin (3), quercetin (4) and eriocitrin (6) showed potent free radical scavenging activity, whereas hesperetin (2) and quercetin (4) showed potent α-glucosidase inhibitory activity.

Guiera senegalensis J.F. Gmel. (Combretaceae) is commonly used as a traditional medicine in Africa. In our previous study, the hydro-alcoholic extracts of the leaves of G. senegalensis showed potent free radical scavenging and enzyme inhibitory activities. Detailed chemical analysis of the 70% ethanol extract afforded 8 phenolic compounds including myricetin (1), myricitrin (2), quercetin (3), (-)-gallocatechin (4), 1,3,4,5-tetra- O-galloylquinic acid (5), gallic acid (6), methyl gallate (7), and ethyl gallate (8). Structures of these compounds were elucidated on the basis of NMR spectroscopic data. Among these compounds, 1,3,4,5-tetra- O-galloylquinic acid (5) (IC50= 7.21 ±0.21 µM), quercetin (3) (IC50 = 7.71 ± 0.17 µM), and myricitrin (2) (0.25 ± 0.03 µM) showed the most potent free radical scavenging, α-glucosidase inhibitory and pancreatic lipase inhibitory activities, respectively.

2( S)-3’,4'-dimethoxy-5,7-dihydroxyflavanone 7- O-neohesperidoside (1), hesperidin (2), astragalin (3), trifolin (4), nicotiflorin (5), narirutin (6), rutin (7), kaempferol 7- O-rutinoside (8), tangeretin (9) and nobiletin (10) were isolated from the MeOH extract of flowers of Citrus ‘Hebesu’. Structures of these compounds were elucidated on the basis of physical and spectral data. Absolute configuration and complete NMR spectral data for compound 1 are reported for the first time in this paper.