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Herba Dendrobii, commonly known as ”Shi-hu”, has been used as a precious traditional Chinese medicine. It is expensive and adulteration arc common due to high demand. The method to distinguish the herb from adulterant species is necessary. In the present study, internal transcribed spacers (ITS) region-based analysis was employed to ascertain the phylogenetic relationship among the 11 Dendrobium and two adulterant species Pholidota articuluta and Flickingeria comate. Results showed that the length of the ITS regions among the thirteen species ranged from 635 to 641 bp and the GC ratio in ITS (ITS1+5.8S+ITS2) regions ranged from 50.55% to 57.25%. Dendrobium species was significantly different from one another by an average of 13.20% and from P. articulata and F comate by 42.00 % and 29.00% respectively. The molecular phylogenetic trees indicated that most of Dendrobium species are closely related and share common clad while both the adulterants outgroup and have separated clad. Therefore, ITS regions can be used as a molecular marker to differentiate medicinal Dendrobium spp. from one another and also from adulterants.

Positive molecular identification of medicinal plants is necessary to their misuse. Dendrobii Caulis is a famous Chinese herbal medicine traditionally used in ophthalmology. However, the identification of the species based on morphology is difficult. In this study, three Dendrobium species were collected and differentiated by the sequences of partial rDNA (ribosomal DNA) sections which contain the ITS 1, 5.8S, and ITS 2 regions. The Dendrobium species used in this reseach included Dendrobium tosaense, Dendrobium officinale, and Dendrobium moniliforme. The length of PCR products are 632 nt for D. tosaense, 627 nt for D. officinale, and 628 nt for D. moniliform, respectively. The similarities of the rDNA region between the species pairs shown range from 91% to 95%. The results we present here may be helpful in identifying other species of Dendrobium.

Background Elderly people with type 2 diabetes mellitus (T2DM) have an increased risk of diabetes-related microvascular and macrovascular complications, thus diabetic patients with a functioning gastrointestinal tract but without sufficient oral intake require enteral nutrition (EN) formulas to control blood glucose. White sweet potato (WSP) was a kind of sweet potato could provide a healthy carbohydrate source to EN formula. The aim of this study was to examine at risk of malnutrition T2DM patients whether a WSP-EN would attenuate glucose response and elevate nutritional index compared to a standard polymeric formulas. Methods In this randomized, parallel, placebo-controlled, pilot clinical trial to investigate the effects of EN with WSP on aged residents with T2DM in long-term care institutions. In total, 54 eligible participants were randomly assigned to either the non-WSP-EN or WSP-EN group. For 60 days, the WSP-EN group received a WSP formula through nasogastric tube via a stoma with a large-bore syringe. The participants received EN of standard polymeric formulas without WSP in the non-WSP-EN group. Results The body weight, body mass index, Mini Nutritional Assessment score, and Geriatric Nutritional Risk Index were significantly higher in the WSP-EN group (p p Conclusions The results suggest WSP incorporated into enteral formulas can improve nutrition status and glycemic control in elderly diabetic patients. Trial registration NCT02711839, registered 27 May 2015.

Dendrobium tosaense is one of the most valuable Chinese medicines and well developed health food. Atopic dermatitis (AD) is a chronic skin disease that occurs mainly in childhood. The pathogenesis of atopic dermatitis had been studied in BALB/c mice modeling by skin-inoculated ovalbumin (OVA) with 2,4,6-trinitro-1-chrolobenzene (TNCB). These mice exhibit features of chronic dermatitis, including skin rash, mast cells infiltration, and elevated serum anti-OVA specific IgE and cytokines modulation. In this study, a standardized ethyl acetate extract of D. tosaense (DtE) was used to protect these mice from the OVA/TNCB-induced skin lesions of atopic dermatitis. The results indicated an increased population of natural T regulatory cell was accompanied by immunosuppression in cytokine profiles and anti-OVA IgE level to significantly reduce Th2 polarization. Finally, toluidine blue staining indicated mast cell infiltration and degranulation was reduced in skin lesion. Our results were shed light on the usage of D. tosaense in AD.

The genus Dendrobium is important in traditional Chinese herbal medicine, and the precise identification of Dendrobium species is critical for the treatment and for pharmacological research. In the present study, a ribosomal DNA (rDNA) internal transcribed spacer (ITS) region-based analysis was used to ascertain the phylogenetic relationship among 20 Dendrobium species. The lengths of the ITS regions among the 20 species ranged from 636 to 653 bp, and the identities of the rDNA regions among the different species ranged from 75.7% to 99.1%. The results also showed that the ITS1 and ITS2 regions exhibit more variation than the 5.8S rDNA. A phylogenetic tree derived from the ITS sequence indicated that six medicinal Dendrobium species, of which five are common medicinal plants in the Taiwan market, were closely related and shared a common clade. Multiplex polymerase chain reaction (PCR) amplification was successfully performed to identify the six medicinal Dendrobium species, and amplification refractory mutation system (ARMS) PCR was used to distinguish D. tosaense specifically from the 19 other Dendrobium species. The established PCR-based (multiplex and ARMS) analyses can be used for the authentication of the raw materials of medicinal Dendrobium from other species.

Here, we studied the functional role of a chloroplast alkaline alpha-galactosidase (OsAkalphaGal) in the breakdown of thylakoid membranes during rice (Oryza sativa) leaf senescence. We assayed the enzyme activity of recombinant OsAkalphaGal with different natural substrates and examined the effect of ectopic OsAkalphaGal expression in rice plants. Recombinant OsAkalphaGal showed at least a two-fold greater substrate-binding affinity and a 10-fold greater turnover rate to galactolipid digalactosyl diacylglycerol than the raffinose family of oligosaccharides (verbascose, stachyose, raffinose) and melibiose. The OsAkalphaGal null mutant (osakalphagal) displayed a delayed leaf senescence phenotype. OsAkalphaGal complementation in osakalphagal recovered OsAkalphaGal expression and showed a senescence phenotype similar to that of wild-type plants. Transgenic plants overexpressing OsAkalphaGal (UbiP-OsAkalphaGal) exhibited retarded plant growth and development, and showed a pale-green phenotype coupled with a reduced chlorophyll content to 42% in newly unfolded leaves. UbiP-OsAkalphaGal leaves also showed a 29-fold increase in alkaline alpha-galactosidase activity compared with wild-type leaves. An ultrastructural study of Ubi-OsAkalphaGal chloroplasts in newly unfolded leaves revealed abnormal grana organization. Our findings strongly suggest that OsAkalphaGal is a thylakoid membrane-degrading enzyme involved in the degradation of digalactosyl diacylglycerol during rice leaf senescence.