PLA nanovectors with encapsulated betulin: plant leaf extract-synthesized nanovectors are more efficacious than PVA-synthesized nanovectors

Objectives

Betulin (BT) is an abundant triterpene found predominantly in the bark of Himalayan birch. It is difficult to deliver it in vivo because of its low aqueous solubility. We have therefore developed novel formulations of BT for improving its solubility, bioavailability and therapeutic efficacy.

Results

Poly-d,l-lactide nanovectors (PLA NVs) were synthesized using poly(vinyl alcohol) and Lonicera japonica leaf extract (LE) as a stabiliser and named as PLA-1 NVs and PLA-2 NVs. PLA-1 NVs and PLA-2 NVs were used for the encapsulation of betulin (BT) and named as BT-En-1 and BT-En-2 NVs. The encapsulation efficiency of BT-En-1 and BT-En-2 NVs were 99.3 and 100 % respectively. Prepared nanoformulations were physically stable. An in vitro study revealed 45 % BT was released over 24 h. BT had a prolonged release from BT-En-2 NVs as compared to BT-En-1 NVs. BT-En-2 NVs had better anticancerous activity against SiHa cells than BT-En-1 NVs.

Conclusions

Developed BT-EN-2 NVs had better biocompatibility, excellent stability and enhanced release characteristics than BT-En-1 NVs.

     

A cold-adapted and glucose-stimulated type II α-glucosidase from a deep-sea bacterium <Emphasis Type="Italic">Pseudoalteromonas</Emphasis> sp. K8

Objectives

To express and characterize a putative α-glucosidase, Pagl, from Pseudoalteromonas sp. K8 obtained via genome mining approach.

Results

Pagl was expressed and purified to homogeneity, with a molecular mass of 60 kDa. It was optimally active at pH 8.5 and 30 °C, and showed cold-adapted activity. Pagl exhibited specific activity towards substrates with α-1,4-linkage, with the highest specific activity of 19.4 U/mg for maltose, followed by pNPαG and maltodextrins, suggesting that Pagl belongs to the type II α-glucosidase. Interestingly, the activity of Pagl is significantly enhanced (2.7 times) in the presence of 200 mM glucose.

Conclusion

The unique catalytic properties of Pagl make it an attractive candidate for several industrial applications.

     

Endoglucanase enzymatic modification of kraft pulp during recycling

Objective

To investigate the cellulose modification process on kraft pulp during recycling by mono-endoglucanase.

Results

Pichia pastoris expressing endoglucanase, EG1, was grown in a 10 l fermenter yielding a high carboxymethyl cellulase (CMCase) activity of 340 U mg^?1. EG1-mediated modification of kraft pulp resulted in a paper sheet with the tensile index and burst index increased by 10 and 6.5 %, respectively. The kink index (indicating abrupt bends in fibres) of the enzyme-treated group decreased sharply by 45 % after the first recycling, compared with a reduction of only 1 % in the control group. Furthermore, EG1 treatment decreased the growth of crystallinity from 73.5 to 73.2 % and crystal size from 7.45 to 7.21 nm, which alleviated paper aging.

Conclusion

Endoglucanase EG1 modifies the interfacial properties of fibers, which affects fibre morphology during the recycling process and improves the technical properties of the resulting pulp and paper.

     

Parthenolide induces apoptosis and autophagy through the suppression of PI3K/Akt signaling pathway in cervical cancer

Objective

To investigate the effect of parthenolide on apoptosis and autophagy and to study the role of the PI3K/Akt signaling pathway in cervical cancer.

Results

Parthenolide inhibits HeLa cell viability in a dose dependent-manner and was confirmed by MTT assay. Parthenolide (6 µM) induces mitochondrial-mediated apoptosis and autophagy by activation of caspase-3, upregulation of Bax, Beclin-1, ATG5, ATG3 and down-regulation of Bcl-2 and mTOR. Parthenolide also inhibits PI3K and Akt expression through activation of PTEN expression. Moreover, parthenolide induces generation of reactive oxygen species that leads to the loss of mitochondrial membrane potential.

Conclusion

Parthenolide induces apoptosis and autophagy-mediated growth inhibition in HeLa cells by suppressing the PI3K/Akt signaling pathway and mitochondrial membrane depolarization and ROS generation. Parthenolide may be a potential therapeutic agent for the treatment of cervical cancer.

     

Molecular understandings on ‘the never thirsty’ and apomictic <Emphasis Type="Italic">Cenchrus</Emphasis> grass

The genus Cenchrus comprises around 25 species of ‘bristle clade’ grasses. Cenchrus ciliaris (buffel grass) is a hardy, perennial range grass that survives in poor sandy soils and limiting soil moisture conditions and, due to the very same reasons, this grass is one of the most prevalent fodder grasses of the arid and semi-arid regions. Most of the germplasms of Cenchrus produce seeds asexually through the process of apomeiosis. Therefore, the lack of sufficient sexual lines has hindered the crop improvement efforts in Cenchrus being confined to simple selection methods. Many attempts have been initiated in buffel grass to investigate the various molecular aspects such as genomic signatures of different species and genotypes, molecular basis of abiotic stress tolerance and reproductive performance. Even though it is an important fodder crop, molecular investigations in Cenchrus lack focus and the molecular information available on this grass is scanty. Cenchrus is a very good gene source for abiotic stress tolerance and apomixis studies. Biotechnological interventions in Cenchrus can help in crop improvement in Cenchrus as well as other crops through transgenic technology or marker assisted selection. To date no consolidated review on biotechnological interventions in Cenchrus grass has been published. Therefore we provide a thorough and in depth review on molecular research in Cenchrus focusing on molecular signatures of evolution, tolerance to abiotic stress and apomictic reproductive mechanism.     

The importance of stem cell engineering in head and neck oncology

Head and neck squamous cell carcinoma is the sixth leading cause of cancer worldwide. The most common risk factors are carcinogens (tobacco, alcohol), and infection of the human papilloma virus. Surgery is still considered as the treatment of choice in case of head and neck cancer, followed by a reconstructive surgery to enhance the quality of life in the patients. However, the widespread use of artificial implants does not provide appropriate physiological activities and often cannot act as a long-term solution for the patients. Here we review the applicability of multiple stem cell types for tissue engineering of cartilage, trachea, vocal folds and nerves for head and neck injuries. The ability of the cells to self-renew and maintain their pluripotency state makes them an attractive tool in tissue engineering.     

Rapid and efficient degradation of bisphenol A by chloroperoxidase from <Emphasis Type="Italic">Caldariomyces fumago</Emphasis>: product analysis and ecotoxicity evaluation of the degraded solution

Objectives

To degrade enzymatically bisphenol A (BPA) that causes serious environmental concerns and is difficult to be degraded by chemical or physical methods.

Results

BPA (150 mg l^?1) was completely degraded by chloroperoxidase (CPO)/H₂O₂ within 7 min at room temperature, atmospheric pressure with the enzyme at 6 μg CPO ml^?1. The degradation products were identified by HPLC–MS, which suggested involvement of multiple steps. Enzymatic treatment followed by existing bioremediation technologies (activated sludge) enhanced removal of COD from 9 to 54 %. Using an ecotoxicity evaluation with Chlorella pyrenoidosa, the degradation products had a lower toxicity than BPA.

Conclusion

BPA can be degraded rapidly and efficiently under mild conditions with chloroperoxidase at 6 μg ml^?1. The degradation products had a lower toxicity than BPA.