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Background: Aging is a process caused by oxidants and aging-related enzymes. Therefore, the inhibition of these processes can exacerbate anti-aging agents. This study aimed to evaluate the antioxidant and anti-aging activities of leaf extracts from seven herbs used in traditional Thai herbal remedies. Methods: Researchers assessed the total levels of phenolic content (TPC), antioxidant, anti-collagenase, and anti-tyrosinase activity using colorimetric methods. Cytotoxicity effects were determined using MTT assays, and matrix metalloproteinases(MMPs) secretion was assessed through gelatin zymography. In addition, inhibitory effects on the growth of microorganisms were examined using the disc diffusion and broth microdilution method.Results: TPC ranged between 48.68–440.91 mg GAE/g of ethanolic leaf extracts. High antioxidant activities against ABTS radicals were detected in P. granatum, P. emblica, P. guajava, T. bellirica, and T. chebula, while high DPPH neutralization appeared in M. coreia, P. guajava, and P. granatum. FRAP assays significantly reduced the power of T. chebula and P. granatum. T. chebula and P. guajava exhibited the highest inhibitory effect on H2O2induced ROS production. P. emblica, P. guajava, T. bellirica, and E. hygrophilus reduced tyrosinase and collagenase activities. P. gaujava, T. chebula, and T. bellirica were shown to inhibit the secretion of MMP-2 from fibroblast cells. All concentrations of leaf extracts were non-toxic to fibroblast cells. P.granatum and T. bellirica could inhibit the growth of P. acnes, E. coli, and S. aureus. Conclusion: Preliminary studies showed that P.granatum and T. bellirica leaf extracts have antioxidants, anti-aging, and anti-bacterial activities, as well as active ingredients suitable for cosmetic products.Keywords: antioxidants, anti-aging, leaf extracts

In vitro propagation is important for rapid multiplication of a wide range of nursery crops or medicinal plants, including stevia (Stevia rebaudiana Bertoni). The aim of this study was to investigate the effects of mineral salts on plant growth and development of stevia shoot cultures. Response surface methodology was used to design experiments by varying three factors: nitrogen salts (NH4NO3 and KNO3), mesos salts (CaCl2, KH2PO4 and MgSO4) and minor elements (Zn-Mn-Cu-Co-Mo-B-I-EDTA-chelated iron). The concentrations of each factor were defined as relative concentrations compared to Murashige and Skoog (MS) concentrations (0.5–3.0 × MS). The effects were evaluated of these three factors on plant quality, multiplication, shoot length and leaf numbers. The minor elements were the most significant factors associated with shoot length and leaf numbers. Increasing minor elements above an MS level of 1 × and decreasing nitrogen tended to increase shoot length significantly. Increasing minor elements and nitrogen up to 3 × MS and increasing mesos to 1.5 × MS were required to improve leaf numbers. Two optimized media were compared to MS for growth characteristics, phenolics and antioxidant activity. One of the media was identified as significantly better than MS for growth, low phenolic production and low antioxidant response. Keywords: Micropropagation, Mineral nutrition, Optimization, Phenolic compounds, Stevia rebaudiana Bertoni

Functional foods (FF) are commonly consumed by Asians, and this trend has increased in recent years. Despite the reported health benefits of FF, it is necessary scrutiny and updates of the underpinning research are important. The first international conference on functional food innovation in Asia (IFFA 2018) took place on January 22nd- 24th, 2018, at the University of Phayao, Thailand. Domestic and international speakers, researchers, nutritionists, dieticians, research scholars and students shared their knowledge and experience in FF research. Key features were the potential beneficial roles of FF in health and disease, the current situation with FF in Asia and innovative trends. The IFFA 2018 involved 2 keynote speakers, 34 invited speakers and 10 sessions. About 250 people from across Asia participated. Key themes, discussions, innovative opportunities, and future directions to link research in academia with health-directed applications as FF are summarised.

Perilla frutescens is commonly used as an n-3-fatty acid source for people living in Northern Thailand. However, cultivated areas are limited because it apparently requires specific growth conditions. Our results suggested that perilla seeds grown in higher altitude in Maehongson province contained more ALA contents than seeds collected from Chiangrai and Nan province. Furthermore, mass spectrometry (MS) proteomic and gene expression analysis revealed that the increase of KASII and FAD3 proteins associated with the mRNA expression and the ALA production. Predictive bioinformatics analysis demonstrated two important transcription factor binding sites, AP2 and B3, which responsible for KASII and FAD3 genes, respectively. The AP2 and B3 transcription factor families were known to be responsible for abiotic stress such as drought and temperature changes. In conclusion, high production of ALA by perilla apparently relies on the altitudes. Moreover, plant responses to abiotic stress environments contribute to the increase of KASII and FAD3 gene and protein expression. However, responsive transcription factors will be further studied for a proof of concept and additionally improving the growing methods in order to increase perilla productivity.

The ability to rapidly generate a pair of aptamers that bind independently to a protein target would greatly extend their use as reagents for two site ('sandwich') assays. We describe here a method to achieve this through proximity ligation. Using lysozyme as a target we demonstrate that under optimal conditions such a pair of aptamers, with nanomolar affinities, can be generated in a single round.

Nucleic acid aptamers are attracting increasing interest as sensing and therapeutic molecules as a consequence of their high affinity and specificity for their target molecules. Aptamers are selected from large random libraries and where structural data are available it appears that only a small fraction of the sequence is actually involved in direct contact with the target. As there are many advantages to minimizing the size of the aptamer a rapid method that can determine those parts of the sequence critical for the target binding would be very useful. In this paper we describe mapping the effective binding region of an aptamer selected against electric eel acetylcholinesterase. As originally selected this aptamer is 77 nucleotides in length and was shown to bind the target with a high affinity (Kd = 174 ± 27 pM). Truncation to 39 nucleotides enhanced affinity for its target by an order of magnitude (Kd = 14 ± 1 pM). To further probe the relationship between sequence and affinity, we used two approaches: truncation and hybridization inhibition. Binding assays were performed with a number of truncated variants to determine a minimal binding sequence. A similar set of measurements for hybridization inhibition was also performed to allow a comparison of the two approaches. In general hybridization inhibition resulted in comparable conclusions to those found by truncation. The exception to this was where the former resulted in steric clashes between double stranded DNA regions and the target. In this case the effect on affinity was less pronounced than with truncation.

The objective of this study was to investigate the in vitro bioactivities associated with the content of phytochemicals in the extracts from perilla seed meal extract (PSME) compared with dietary seed (PSE). PSE had higher total phenolics and flavonoids content than PSME. However, hydrophilic phytochemical contents in PSME were quantitatively equivalent to PSE. Rosmarinic acid was predominantly found in both extracts. Cell viability and anti‐mutagenicity testing demonstrated that PSE and PSME were biosecured and non‐genotoxic. Both extracts strongly scavenged free radicals and significantly reduced reactive oxygen species (ROS) production. The extracts drastically diminished nitric oxide (NO) production of LPS‐treated RAW 264.7 cells via iNOS mRNA expression. The expression of IL‐6 and COX‐2 were evidently inhibited by these extracts. It could be concluded that PSE and PSME clearly showed in vitro anti‐mutagenicity, antioxidant and anti‐inflammatory capacities. In particular, the by‐product perilla seed meal could be considered as a high nutritive functional food. PRACTICAL APPLICATIONS: This study suggests that the seed meals, a by‐product from seed oil industry, can be utilized as a valuable dietary source for humans and animals. The high content of polyphenols and their bioactivities can be developed as functional foods, and excipients and fillers in pharmaceuticals and nutraceuticals production. Moreover, recycling of the by‐product seed meals should also reduce environmental and sanitary pollution.

We report here the in vitro selection of DNA aptamers for electric eel acetylcholinesterase (AChE). One selected aptamer sequence (R15/19) has a high affinity towards the enzyme (Kd = 157 ± 42 pM). Characterization of the aptamer showed its binding is not affected by low ionic strength (~20 mM), however significant reduction in affinity occurred at high ionic strength (~1.2 M). In addition, this aptamer does not inhibit the catalytic activity of AChE that we exploit through immobilization of the DNA on a streptavidin-coated surface. Subsequent immobilization of AChE by the aptamer results in a 4-fold higher catalytic activity when compared to adsorption directly on to plastic.