The demand for skin-whitening agents is high across the world, including Asian countries. An extensive screening using a tyrosinase inhibition assay was performed in order to discover novel plant materials. In our research program investigating a safe and effective agent, 50% ethanolic extracts prepared from discarded parts of Prunus persica were screened for in vitro tyrosinase inhibitory activity. Among the extracts tested, twig extract showed the most potent inhibitory activity: 38% inhibition at 500 µg/mL. The investigation of active compounds in twig extract found four flavanones that acted as moderate inhibitors, including (−)-prunin, persiconin, (+)-dihydrokaempferol, and (−)-naringenin. These compounds were only observed in the twig extract following preliminary quantification by HPLC, with the following concentrations: (−)-prunin, 1.8 mg/g sample; persiconin, 0.8 mg/g sample; (+)-dihydrokaempferol, 0.8 mg/g sample; (−)-naringenin, 1.7 mg/g sample. These results suggest that twig extracts can be more useful for skin-whitening compared with other parts of the plant. In addition, a new constituent of twig extract was identified, namely isoquercitrin, which suggests that twig extract can be a potent source of flavones and flavanones. Further studies on the identification of novel compounds from twig extract are now underway in our laboratory.

This study examines the effect of quantity sold (sales volume) on profitability of market participating smallholder farmers in northern Ghana. Market participation has been shown to be important for increasing incomes and improving production efficiency for farm households but still remains low in SSA. While agribusiness and development experts generally advocate for more intensive market participation, it is not clear if selling more results in more profits for smallholder farmers in remote markets that are prone to exorbitant transaction costs. The data used in this study is from the APS survey conducted in 2013 and 2014 in Northern Ghana which had a sample size of 527. The study is based on the theory of profit maximization, in which separability is inferred from observed market participation. OLS regression is used for empirical estimation after rejecting the hypothesis of endogeneity in the model. Mean gross margin/ kg across four groups of farmers ranked by quantity sold is also statistically examined. The results confirm the existence of economies of scale and also show that different crops have different effects on profitability. The results also show that although unambiguously positive, the relationship between quantity sold and profitability may not be linear.

During the course of Citrus unshiu fruit cultivation, large amounts of plant material including pruned leaves, thinned-out flowers and unripe fruit are obtained; these materials are generally considered unusable and discarded as plant wastes. We have previously attempted to establish an effective use of such plant wastes as beneficial natural resources and found that a methanolic extract of pruned Citrus leaves (CUL-ext) exhibited inhibitory activity against porcine pancreatic lipase. In this study, we sought to identify further the effective uses of C. unshiu plant wastes by determining the lipase inhibitory activity of methanolic extracts of thinning out flowers (CUF-ext) and unripe fruit (CUUF-ext). We accordingly found that the inhibitory activity of CUF-ext was superior to that of CUUF-ext and comparable to that previously observed using CUL-ext. Fractionation of CUF-ext and CUUF-ext, followed by chromatographic analyses, revealed that the pancreatic lipase inhibitory activities of these extracts could be attributed, at least in part, to the flavonoids hesperidin, nobiletin, narirutin and rutin. On the basis of present findings, we propose that, in addition to pruned Citrus leaves, the thinned-out flowers and unripe fruit of C. unshiu are natural resources which are suitable for preparing constituents with lipase inhibitory activity.

Ciguatera is the term for poisoning resulting from eating fish from tropical or subtropical regions. The causative toxins collectively named ciguatoxins (CTXs) widely differ in structures depending on their geographic origins, which range from the Pacific Ocean and the Indian Ocean to the Caribbean Sea. Neurotoxic shellfish poisoning (NSP) is caused by the ingestion of bivalve shellfish contaminated with brevetoxins (BTXs). Structurally, both CTXs and BTXs consist of fused ether rings aligned in a ladder shape. Pharmacologically, they bind at the same site (site-5) of voltage-gated sodium channels. However, the great structural diversity and the rare availability of reference toxins hinder LC-MS and ELISA methods, which operate on structure-based recognition. In this study, we prepared a chemiluminescent ligand, acridinium BTXB2 (ABTX), and tested its suitability for use in competitive binding assays to detect CTXs and BTXs. The affinity of ABTX to the rat brain synaptosome estimated by Ki (1.66 pM) was approximately two-fold higher than that of PbTx-3 (BTX3). In addition, the equilibrium dissociation constant (KD) was 0.84 nM, the maximum number of binding was 6.76 pmol toxin/mg protein, and the detection limit was 1.4 amol. The assays performed on samples spiked with CTX3C or BTXB4 (N-palmitoylBTXB2) at 0.2-1.0 ng CTX/g fish flesh, and 200-800 ng BTXB4/g shellfish showed a linear relationship between the theoretical and observed toxin amounts.

Since Cav3.2 T-type Ca2+ channels (T-channels) expressed in the primary afferents and CNS contribute to intractable pain, we explored T-channel-blocking components in distinct herbal extracts using a whole-cell patch-clamp technique in HEK293 cells stably expressing Cav3.2 or Cav3.1, and purified and identified sophoraflavanone G (SG) as an active compound from SOPHORAE RADIX (SR). Interestingly, hop-derived SG analogues, (2S)-6-prenylnaringenin (6-PNG) and (2S)-8-PNG, but not naringenin, also blocked T-channels; IC50 (μM) of SG, (2S)-6-PNG and (2S)-8-PNG was 0.68-0.75 for Cav3.2 and 0.99-1.41 for Cav3.1. (2S)-6-PNG and (2S)-8-PNG, but not SG, exhibited reversible inhibition. The racemic (2R/S)-6-PNG as well as (2S)-6-PNG potently blocked Cav3.2, but exhibited minor effect on high-voltage-activated Ca2+ channels and voltage-gated Na+ channels in differentiated NG108-15 cells. In mice, the mechanical allodynia following intraplantar (i.pl.) administration of an H2S donor was abolished by oral or i.p. SR extract and by i.pl. SG, (2S)-6-PNG or (2S)-8-PNG, but not naringenin. Intraperitoneal (2R/S)-6-PNG strongly suppressed visceral pain and spinal ERK phosphorylation following intracolonic administration of an H2S donor in mice. (2R/S)-6-PNG, administered i.pl. or i.p., suppressed the neuropathic allodynia induced by partial sciatic nerve ligation or oxaliplatin, an anti-cancer agent, in mice. (2R/S)-6-PNG had little or no effect on open-field behavior, motor performance or cardiovascular function in mice, and on the contractility of isolated rat aorta. (2R/S)-6-PNG, but not SG, was detectable in the brain after their i.p. administration in mice. Our data suggest that 6-PNG, a hop component, blocks T-channels, and alleviates neuropathic and visceral pain with little side effects.

Hydroxychavicol (HC), which is obtained from the leaves of Piper betle LINN. (Piperaceae), inhibits xanthine oxidase (XO) with an IC50 value of 16.7 µM, making it more potent than the clinically used allopurinol (IC50=30.7 µM). Herein, a structure-activity relationship analysis of the polar part analogs of HC was conducted and an inhibitor was discovered with a potency 13 times that of HC. Kinetic studies have revealed that HC and its active analog inhibit XO in an uncompetitive manner. The binding structure prediction of these inhibitor molecules to the XO complex with xanthine suggested that both compounds (HC and its analog) could simultaneously form hydrogen bonds with xanthine and XO.

In our research program to find novel agents for alopecia from natural plant resources, we screened Euphorbiaceae plant extracts using an anti-5α-reductase assay. Among the samples tested, the extract of Phyllanthus urinaria showed the most potent activity with 24.3 and 64.6% inhibition at 50 and 200 µg/mL against the enzyme, respectively. The extract also suppressed the androgen activity of dihydrotestosterone in LNCaP cell line. These results show that the extract of P. urinaria may be a multi-potent agent for androgen-derived alopecia. We tested for activity on a hair regrowth model using mice. The extract of P. urinaria showed hair regrowth activity at 5 mg/mouse/d administration. Furthermore, the active principle for anti-5α-reductase activity was determined as stigmasterol glucoside from activity-guided fractionation and the IC50 was 27.2 µM. These results suggest that extract of P. urinaria may be a promising candidate anti-alopecia agent.

The purpose of this study was to examine an inhibitory effect of mango leaf extracts on advanced glycation end products (AGEs) formation and to identify these active ingredients, and also to investigate a relationship between leaves maturation and the inhibitory activity. A methanolic extract of old dark green mango leaf extract (OML-ext) exhibited an inhibitory activity of AGEs formation in nonenzymatic glycation of albumin. The inhibitory activity of OML-ext was attributable to 3-C-β-D-glucosyl-2,4,4’,6-tetrahydroxybenzophenone (1), mangiferin (2) and chlorophyll. Inhibitory effect of young dark reddish brown mango leaf extract (YDL-ext) on AGEs formation was similar to that of OML-ext. The inhibitory activity of YDL-ext was attributable to 1 and 2, in addition, a part of the the activity of YDL-ext due to anthocyanins whose content is highest in young dark reddish brown mango leaves. Considering the amounts of leaves obtained from pruning, old dark green leaves may be a reasonable natural resource for the preparation of ingredients with inhibitory activity of AGEs formation.

The purpose of this study was to search edible ripe Citrus fruits which are applicable for functional food materials as juice, tea and/or jam with sweet taste and rich aroma. A fifty percent ethanolic extract (CMR-ext) obtained from the edible ripe fruit of Citrus madurensis exhibited an inhibitory activity of antigen-induced degranulation in anti-dinitrophenyl (DNP) IgE antibody sensitized rat basophilic leukemia (RBL) -2H3 cells. The inhibitory effect of the CMR-ext on degranulation in RBL-2H3 cells was attributable to 3’,5’-di-C-β-glucopyranosylphloretin (1) which is a constituent of C. madurensis. The effect of 1 on Akt and mitogen-activated protein kinases (MAPK) phosphorylation was examined in RBL-2H3 cells. Western blot analysis revealed that 1 (50 μM) inhibited the degranulation by suppression of Akt and p38 phosphorylation.

BACKGROUND: Morinda citrifolia (Rubiaceae), commonly known as noni is distributed throughout tropical and sub-tropical regions of the world. Anti-allergic effects of noni have not been reported despite the clinical usage as an anti-allergic agent. MATERIALS AND METHODS: To investigate the anti-allergic effects of the 50% ethanolic extract of M. citrifolia fruits and leaves (MCF-ext and MCL-ext), dinitrofluorobenzene (DNFB)-induced triphasic cutaneous reaction and picryl chloride-induced contact dermatitis (PC-CD) tests were performed. RESULTS: In DNFB-induced triphasic cutaneous reaction, oral administration of MCF-ext and MCL-ext exhibited dose-dependent inhibition of cutaneous reaction at 1 h (immediate phase response) after the DNFB challenge. MCF-ext also inhibited ear swelling at 24 h (late phase response) and 8 days (very late phase response) after the DNFB challenge. The effect of MCL-ext on the immediate phase response was attributed to the anti-degranulation from RBL-2H3 cells, while MCF-ext had no significant effect on degranulation. The active components of anti-degranulation activity in MCL-ext were determined to be ursolic acid, rutin and kaempferol-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside. In the PC-CD test, both MCF-ext and MCL-ext showed an anti-swelling effect but the potency of MCF-ext was stronger than MCL-ext. CONCLUSION: These data suggest that noni fruits and leaves can be a daily consumable material for the prevention of allergic symptoms.

BACKGROUND: Kaempferia parviflora rhizome is used as a folk medicine in Thailand for the treatment of various symptoms. In the present study, the inhibitory activities of extract from K. parviflora rhizome against 5α-reductase (5αR) were subjected. Furthermore, the effects of the extract from K. parviflorar hizome in benign prostate hyperplasia (BPH) were studied using the model mice. MATERIALS AND METHODS: Preparations of extracts from the rhizomes of K. parviflora, Curcuma zedoaria and Zingiber officinale, and methoxyflavones isolated from K. parviflora was used for 5αR inhibition assay. The effects of K. parviflora extract on growth suppression for the prostates and seminal vesicles were performed based on the Hershberger's method. The K. parviflora extract was administered to castrated mice for 14 days. RESULTS: K. parviflora extract showed more potent inhibitory activity on 5αR than C. zedoaria and Z. officinale extracts. The active principles were identified as 3,5,7,3',4'-pentamethoxyflavone and 5,7,3',4'-tetramethoxyflavone by activity guided fractionation. Furthermore, K. parviflora extract suppressed the weights of prostates and seminal vesicles in BPH model rats by daily administration for 14 days. CONCLUSION: These results indicate that K. parviflora extract can be a promising agent for the treatment of BPH.

Rates of gouty arthritis with hyperuricemia have increased recently as it has become a lifestyle-related disease. We reviewed historical treatments for pain due to gouty arthritis in traditional Chinese medical books, with special interest in pathological causes, including dietary and drinking habits, as well as the frequency of crude drugs used in historical prescriptions. From the present historical survey, we showed that six traditional terms may be equivalent to modern gouty arthritis and that the "Manbyokaishun," a formulary edited in the 16th century in China, included medical information for gouty arthritis. Furthermore, the 46 prescriptions, including Sokeikakketsuto, mentioned in the "Manbyokaishun," were selected as likely treatments for gouty arthritis. The most common crude drugs in the 46 prescriptions were aconite root, angelica root, cinnamon bark, peony root and saposhnikovia root. The inhibitory activity of these crude drugs extracts against xanthine oxidase was investigated. Angelica root and saposhnikovia root showed more potent inhibitory activity (20% at 250 microg/mL) than aconite root (16%), notopterygium rhizome (15%) and cinnamon bark (12%).

Bad breath is a topic of general interest. In this study, the treatment for bad breath in traditional Chinese medicine was reviewed with a special focus on pathologic diagnosis and crude drug prescriptions. It was shown that bad breath developed based on both systemic and local diseases. Some systemic conditions, including nasal, paranasal, pulmonary and digestive diseases, are considered to cause bad breath. The morbid state of a patient with bad breath has been recognized as being based on "heat syndrome" and "Qi-stagnation syndrome." Bad breath based on "heat syndrome" is manifested as thirst and ulceration of the oral cavity, and has been treated with crude drugs such as Coptis rhizome, Scutellaria root and gypsum. One case study reported that bad breath resulting from a dry mouth was treated with byakkokaninjinto, a Kampo formulation containing gypsum. "Qi" is considered to be the vital energy of all life forms including for the functioning of organs and mental and emotional activity. "Qi-stagnation syndrom," referring to the dysfunction of organs, is manifested as psychosomatic symptoms such as irritability, a flushed face and restlessness. Bad breath based on "Qi-stagnation syndrome" has been treated with crude drugs such as Cnidium rhizome, clove and cinnamon bark. Modern dental and medical treatment both accept the participation of psychogenic agents in the development of bad breath. Bad breath also develops based on periodontal and oral diseases. This type of bad breath has been treated with mouth-wash (collutorium) containing Asiasarum root, Angelica dahurica root and Cnidium rhizome. This historical evidence regarding crude drug prescriptions contributes to the development of mouth care products for preventing and treating bad breath.

Ginseng is prepared from Panax ginseng C.A. Meyer root. The root of wild P. ginseng has long tortuous rhizome called traditionally "Rozu" in Japanese. In the present historical studies on ginseng, it has been proven that ginseng has sometimes been used after removing "Rozu" due to its emetic effects. However, ginseng with "Rozu" is prescribed in almost all the present Kampo formulations used clinically in China and Japan. Possible reasons for this are (1) some formulations including "Rozu" have been used for vomiting resulting from the retention of fluid in the intestine and stomach, "tan-in" in Japanese, and (2) the present cultivated ginseng has shorter "Rozu" than wild ginseng. Furthermore, it is proved that "Rozu", rich in ginsenoside Ro with oleanane-type aglycone, is distinguished from ginseng roots rich in ginsenosides Rb1 and Rg1 with dammarane-type aglycone. This is the first report to declare the distribution of ginsenosides in underground parts of wild P. ginseng. Ginsenoside Ro is a minor ginsenoside in ginseng whereas it is the major ginsenoside in P. japonicus rhizome (chikusetsu-ninjin in Japanese). Ginsenoside Ro is characterized by antiinflammatory effects which differ from ginsenosides Rb1 and Rg1 responsible for adaptogenic effects of ginseng. These results suggest that "Rozu" containing both oleanane- and dammarane-type ginsenosides might be a promising raw material distinct from ginseng root or P. japonicus rhizome.

Japanese Angelica root, Toki in Japanese, is prepared from the roots of cultivated Angelica acutiloba or A. acutiloba var. sugiyamae. Since Toki has been frequently used as a crude drug in traditional Chinese formulations, the stable supply and quality of Toki are essential issues in Japanese clinical practice. To clarify the historical and present conditions of Toki, a historical survey on herbal books and a field investigation on the cultivation condition of A. acutiloba in the Fuki area (Wakayama Prefecture) were carried out. From the present historical survey, it was proven that Yamato-Toki produced in the Yamato area, an old local area including the current Nara and Wakayama prefectures in Japan, had been considered to be superior merchandise. It was also proven that a special processing method to prevent flower stalk growth ("Mekuri" in Japanese) is an original method different from Chinese methods. From the present field investigation, it was also proven that the traditional transplant operation of the second year has been handed down since the 1930s and that washing roots in hot water ("Yumomi" in Japanese) is an original method of preparing Yamato-Toki. Toki is one of the precious crude drugs cultivated and prepared in Japan. The present study may help to pass on traditional cultivation culture and contribute to an expansion in the volume of Yamato-Toki produced in Japan.