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Ocimum gratissimum L. is a fragrant plant of the Lamiaceae family. O. gratissimum has been used in folk medicine, cosmetics, and food industry. In this study, herbs of O. gratissimum were collected in the summer in Northern Vietnam and extracted for essential oils by hydrodistillation, followed by gas chromatography - mass spectrometry (GC-MS) analysis. The efficiency of essential oil extraction was 0.2258% ± 0.0735. According to the analysis results, twenty-seven components were identified. The main ingredients include Eugenol (65.135%), Ocimene (7.20%), Caryophyllene (6.64%), and Germacrene D (12.03%). This result suggests that the O. gratissimum essential oil is a potential source of antimicrobial, preservative and flavoring agent.

Schefflera octophylla L is a traditional medicine that exhibits a wide range of biological activities. However, the phytochemical content of S. octophylla L.essential oil is limitedly known. In the present study, S. octophylla L. grown in Hai Duong province (Vietnam) was extracted for essential oil by using hydrodistillation method. The resulted S. octophylla essential oil was further analyzed for its composition of volatile components by GC-MS analysis. Results have shown that the extraction process yielded 0.162 wt% of S. octophylla essential oil. In addition, the content of volatile substances in the obtained essential oil accounted for 97.07%, with main constituents known to have significant medicinal value such as myrcene (9.0%), elemene (6.67%), caryophylene (= caryophylene ) (24.91%), selinene (6.30%) and selinene (7.29%). These findings provide a helpful insight to S. octophylla L phytochemical profiles for further studies on the plant applications in the fields of pharmaceuticals, cosmetics, agriculture and therapeutic uses.

An environmentally benign method for the mineralization of sulfur mustard has been proposed involving chemical hydrolysis of sulfur mustard to thiodiglycol, and then the biological degradation of thiodiglycol to generate biomass and gaseous carbon dioxide. Alcaligenes xylosoxidans (SH91) was isolated based on its ability to utilize thiodiglycol as a sole carbon source. This article compares different biological reactor designs and experimentally assesses their relative effectiveness in degrading thiodiglycol using pure cultures of SH91. The reactor configurations studied are batch, continuous stirred-tank reactor (CSTR), and CSTR with cell recycle. From the results, it is clear that the CSTR with cell recycle offers superior performance for a given residence time or volume. These pure culture data are necessary for accurate design of a pilot-scale system where mixed cultures will be employed because of a possible incomplete chemical hydrolysis step.

The insect larvae/baculovirus protein production process was dramatically simplified by expressing fusion proteins containing green fluorescent protein (GFP) and the product-of-interest. In this case, human interleukin-2 (hIL-2) and chloramphenicol acetyl-transferase (CAT) were model products. Specifically, our fusion construct was comprised of a histidine affinity ligand for simplified purification using immobilized metal affinity chromatography (IMAC), the UV-optimized GFP (GFPuv) as a marker, an enterokinase cleavage site for recovery of the product from the fusion, and the product, hIL-2 or CAT. Both the approximately 52 kDa GFPuv/hIL-2 and approximately 63 kDa GFPuv/CAT fusions were expressed in Trichoplusia ni larvae at 9.0 microg-hIL-2 and 24.1 microg-CAT per larva, respectively. The GFP enabled clear identification of the infection process, harvest time, and more importantly, the quantity of product protein. Because the GFP served as a marker, this technique obviates the need for in-process Western analyses (during expression, separation, and purification stages). As a purification marker, GFP facilitated rapid identification of product-containing elution fractions (Cha et al., 1999b), as well as product-containing waste fractions (e.g., cell pellet). Also, because the fluorescence intensity was linear with hIL-2 and CAT, we were able to select the highest-producing larvae. That is, three fold more product was found in the brightest larva compared to the average. Finally, because the GFP is attached to the product protein and the producing larvae can be selected, the infection and production processes can be made semi-continuous or continuous, replacing the current batch process. These advantages should help to enable commercialization of larvae as expression hosts.

Many eukaryotic proteins have been successfully expressed in insect cells infected with a baculovirus in which the foreign gene has been placed under the control of a viral promoter. This system can be costly at large scale due to the quality of virus stock, problems of oxygen transfer, and severity of large-scale contamination. To circumvent this problem, we have investigated the expression of a foreign protein, human interleukin-2 (IL-2), in insect larvae, Trichoplusia ni, infected with the baculovirus Autographa californica nuclear polyhedrosis virus (AcNPV). The IL-2 gene was placed under control of the p10 promoter so that the polyhedra remained intact for efficient primary infection. From our results, it was clear that early infection limited larval growth and late infection delayed product production until near pupation, hence infection timing was important. Also, the harvest time was crucial for obtaining high yield, because IL-2 production had a sharp optimal peak with a time of occurrence dependent on both temperature and the initial amount of infection virus. Specifically, we found that, by raising the infection temperature to 30 degrees C, we more than doubled the protein productivity. Furthermore, a significant concern of the larvae/baculovirus expression system has been the large amount of protease produced by the larvae, which adversely affects the protein yield. Therefore, we screened several protease inhibitors and characterized the larval protease specificity and timing to attenuate their impact. This report elucidates and delineates the factors that most directly impact protein yield in the larvae expression system, using IL-2 as a model.