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This work aimed to investigate the phytochemical, antioxidant and antibacterial activities of the various colors wild grape fruits extracted by different solvents; water, methanol and ethanol. The total phenolic (TPC) and flavonoid (TFC) contents were analyzed by Folin-Ciocalteu and colorimetric aluminum chloride assays, respectively, while antioxidant activities were determined using 2,2?-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. The antibacterial activity against infective bacteria using agar well diffusion method of the extracts was also tested. Methanolic extracts showed the highest of TPC comparison to other extracts, especially in green extract. The ethanolic extracts of red and black fruits showed the highest of TFC whereas the green extract using methanol showed the highest TFC. The methanolic extracts of all color showed the lowest of IC50 values when compared to other solvents in the same color. Among them, the methanolic extract of green has the lowest of IC50 values which considered to be the highest powerful of antioxidant activity. The obtained results were directly trend with the FRAP values. However, the ethanolic extract showed similar antioxidant activity as comparison to the methanolic extract. The methanolic extract from green fruits showed good antibacterial activity. All ethanolic extracts showed widely and similarly on selected bacteria inhibition, but no activity was observed in all water extracts. The MIC and MBC of all extracts were in ranged of 250-500 µg/mL. The obtained results revealed that extraction solvents and different colors of wide grape fruits were the main factors on the phytochemicals and biological activities of the wild grape.

The fresh juice extracts of wild grape (Ampelocissus martini Planch.) fruits in different colors; green, red and black were used for investigation of their phytochemicals and antioxidant activity. This fruit is much similar when compared to the cultivated grape, an important source of phytochemicals, and never been reported about their biological activities. The fresh juice extracts were evaluated for total phenolic content (TPC), and total flavonoid content (TFC) by using Folin-Ciocalteu assay and colorimetric aluminum chloride assay, respectively. The antioxidant activities were carried out using DPPH and FRAP assays. In addition, the antibacterial activity of the extracts was also performed by agar well diffusion method. The fresh juice extract of wild grape fruits showed high contents of TPC and TFC, especially the juice extract from black color (11.37±0.25 mg GAE/g FW and 19.41±0.30 mM FeSO4/g FW for TPC and TFC, respectively). However, the fresh juice extracts from green color exhibited the highest antioxidant activities. In contrast, the antibacterial activity of the juice extract from red color of wild grape fruits were wide against 14 strains and at least 6 strains of pathogenic bacteria were also susceptible against the juice extract of green color. In conclusion, this work confirmed the strong antioxidant and antibacterial activities of wild grape fruits extracts. The result suggested that this fruit might be used as a powerful source of phytochemicals and biological activities.

The objective of this research was to prepare Eri silk fibroin solution for preparing silk film loaded chlorhexidine drug as model for hydrophilic drug release. The Eri silk cocoons were boiled in 0.5%NaCO3 solution at 90℃, and then left in air dried at room temperature. The fibroin was dissolved in 9M (Ca(NO3)2) with ethanol (2 by mole) and heated at 70℃. The silk fibroin (SF) solution was then dialyzed to exclude salt in phosphate buffer. The SF and gelatin (G) solutions were mixed for preparation of films in both with and without chlorhexidine. The films were observed their morphology under scanning electron microscope. The results found that all of films were rough of their surfaces, homogeneous texture without phase separation. The native SF film composed of pores throughout the film area but did not observe in native G film. The results also showed that the SF and G can be good interacted to form hydrogen bonds. These were indicated from FTIR spectra and thermal analysis. The chlorhexidine drug has not affect on the changes of film properties. However, the releasing pattern of chlorhexidine from each film was varied. The highest rate of drug releasing was found in the native SF film while the native G film was the lowest. It might be suggested that the drug releasing rate was depended on polarity of each polymer components.

This study aimed to prepare Silk Fibroin (SF) and Gelatin (G) blend film and study its morphology, secondary structure and thermal properties compared to native SF and G films. The films were prepared from the SF solution by casting on the polystyrene plates. They were investigated their secondary structure by fourier transform-infrared (FTIR) spectroscopy, morphology using Scanning Electron Microscope (SEM). In addition, Thermogravimetric Analysis (TG) and Differential TG (DTG) were used for thermal properties investigation. The results found that the SF/G blend film composed of both alpha-helix and beta-sheet structures which were similar characteristics of the native SF and G. This result was similar to the TG and DTG analysis according to blending between SF and G is not enhancing thermal stability of the film. However, changes in some absorption bands and temperatures were also observed from the blend film. The result suggested that chemical interaction and hydrogen bonding between SF and G could be formed. The formation could be affected to the uniform of the surface throughout the film under SEM.

This study aimed to prepare Eri (Philosamia ricini) Silk Fibroin (SF)/chitosan (CS) blend films by a solvent evaporation method and to compare the blend films with both native SF and CS films. Influence of SF ratios on the morphology, secondary structure and thermal decomposition of the CS blend films were investigated. The native SF and CS films were uniform and homogeneous without phase separation. For the blend films, the uniform can be found less than 60% of SF composition. All of SF/CS blend films showed both SF and CS characteristics. FT-IR results showed that the blend films composed of both random coil and beta-sheet with predominant of beta-sheet form. Interaction of intermolecular between SF and CS have occurred which were measured by thermogravimetric thermograms. Increasing of SF contents was leading to the increase of beta-sheet structures which were enhanced the thermal stability of the CS blend films.

The study aimed to investigate and compare some characteristics of Bombyx mori and Eri (Philosamia ricini) silks in different forms; with and without sericin. The protein contents were measured and find out the composition of the silk fibroin and sericin proteins by Lowry method. The secondary structure and thermal behavior of all kind of silk were determined by FT-IR and TA instrument, respectively. The B. mori composed of more amount of sericin content than that of Eri silk. FT-IR spectra indicated that the Eri silk was similar profile of silk with and without sericin, whereas B. mori silk showed dramatically differed. With sericin, B. mori composed of higher ratio random coil and alpha-helix structures than beta-structure. With thermogravimetric analysis, both B. mori and Eri silk fibers without sericin showed higher stability than that silk fiber with sericin. This is due to the crystalline region of hydrophobic amino acid composed in the fibroin core protein. The differential scanning calorimetry thermogram of B. mori was differed from Eri silk fiber. It is a promising that characteristics of the silk were influenced by both silk components and silk varieties.