Evaluation on Antidiabetic Properties of Medicinal Plants from Myanmar.

OBJECTIVES: To explore the effective and safe medicines for treating diabetes. METHODS: Hydroalcoholic extracts of 130 medicinal plants belonging to 66 families were evaluated using porcine pancreatic lipase (PPL) inhibition and glucose uptake methods together with a literature review. RESULTS: The extracts of 22 species showed the PPL inhibition activity; 18 extracts of 15 species stimulated glucose uptake in 3T3-L1 adipocytes. Among them, Mansonia gagei J.R. Drumm., Mesua ferrea L., and Centella asiatica (L.) Urb. exhibited both activities. The extracts of Caladium lindenii (André) Madison rhizomes and Azadirachta indica A. Juss. leaves presented the utmost lipase inhibitory activity with IC50 of 6.86 ± 0.25 and 11.46 ± 0.06 µg/mL, respectively. The extracts of Coptis teeta Wall. rhizomes and Croton tiglium L. seeds stimulated the maximum glucose uptake. Ten species are reported to have antidiabetic activity for the first time. Flavonoids and triterpenoids are the dominant antidiabetic compounds in selected medicinal plants from Myanmar. CONCLUSIONS: P. zeylanica, L. cubeba, H. crenulate, M. gagei, C. teeta, and M. ferrea are worthy to advance further study according to their strong antidiabetic activities and limited research on effects in in vivo animal studies, unclear chemical constitutes, and safety.

Characterization of non-covalent immobilized Candida antartica lipase b over PS-b-P4VP as a model bio-reactive porous interface.

The design of interfaces that selectively react with molecules to transform them into compounds of industrial interest is an emerging area of research. An example of such reactions is the hydrolytic conversion of ester-based molecules to lipids and alcohols, which is of interest to the food, and pharmaceutical industries. In this study, a functional bio-interfaced layer was designed to hydrolyze 4-nitrophenyl acetate (pNPA) and Ricinus Communis (castor) oil rich in triglycerides using lipase b from Candida antarctica (CALB, EC 3.1.1.3). The attachment of CALB was performed via non-covalent immobilization over a polymer film of vertically aligned cylinders that resulted from the self-assembly of the di-block copolymer polystyrene-block-poly(4-vinyl pyridine) (PS-b-P4VP). This polymer-lipase model will serve as the groundwork for the design of further bioactive layers for separation applications requiring similar hydrolytic processes. Results from the fabricated functional bio-interfaced material include cylinders with featured pore size of 19 nm, d spacing of 34 nm, and ca. 40 nm of thickness. The polymer-enzyme layers were physically characterized using AFM, XPS, and FTIR. The immobilized enzyme was able to retain 91% of the initial enzymatic activity when using 4-nitrophenyl acetate (pNPA) and 78% when exposed to triglycerides from castor oil.

Preparation of High-Purity Trilinolein and Triolein by Enzymatic Esterification Reaction Combined with Column Chromatography.

High-purity trilinolein and triolein were prepared by Novozym 435-catalyzed esterification reaction combined with column chromatography purification in this study. Firstly, linoleic acid and oleic acid were respectively extracted from safflower seed oil and camellia seed oil by urea adduct method. Secondly, trilinolein and triolein were synthesized through Novozym 435 catalyzed esterification of glycerol and fatty acids. The best synthesis conditions were obtained as follows: reaction temperature 100°C, residual pressure 0.9 kPa, enzyme dosage 6%, molar ratio of glycerol to linoleic acid 1:3 and reaction time 8 h. Crude trilinolein and triolein were further purified by silica gel column chromatography. Finally, highpurity trilinolein (95.43±0.97%) and triolein (93.07±1.05%) were obtained.

Isolation, purification and characterization of a novel solvent stable lipase from Pseudomonas reinekei.

The Pseudomonas sp. have been long recognized for their exogenous lipolytic activities yet the genus still contains a lot of unexplored strains. Due to the versatile metabolic machinery and their potential for adaptation to fluctuating environmental conditions Pseudomonas sp. are of great interest for biotechnological applications. In this study, a new extracellularly produced lipolytic enzyme from Pseudomonas sp. (P. reinekei) was purified and characterized. The production of lipase from P. reinekei (H1) was enhanced 10-fold by optimizing the nitrogen source. The 50 kDa H1 lipase was purified using negative and positive mode anion exchange chromatography. The purified lipase was active over a broad pH range (5.0-9.0) and was stable for 24 h at 40 °C. The lipase showed significant stability, and indeed activation, in the presence of organic solvents with log P ≥ 2.0. These features render this lipase of interest as a biocatalyst for applications such as biodiesel production, detergent formulations and biodegradation of oil in the environment.

A novel protocol for the preparation of active recombinant human pancreatic lipase from Escherichia coli.

An active recombinant human pancreatic lipase (recHPL) was successfully prepared for the first time from the Escherichia coli expression system using short Strep-tag II (ST II). The recHPL-ST II was solubilized using 8 M urea from E.coli lysate and purified on a Strep-Tactin-Sepharose column. After refolding by stepwise dialyses in the presence of glycerol and Ca2+ for 2 days followed by gel filtration, 1.8-6 mg of active recHPL-ST II was obtained from 1 L of culture. The recHPL was non-glycosylated, but showed almost equal specific activity, pH-dependency and time-dependent stability compared to those of native porcine pancreatic lipase (PPL) at 37°C. However, the recHPL lost its lipolytic activity above 50°C, showing a lower heat-stability than that of native PPL, which retained half its activity at this temperature.

Lipase Immobilization on Silica Xerogel Treated with Protic Ionic Liquid and its Application in Biodiesel Production from Different Oils.

Treated silica xerogel with protic ionic liquid (PIL) and bifunctional agents (glutaraldehyde and epichlorohydrin) is a novel support strategy used in the effective immobilization of lipase from Burkholderia cepacia (LBC) by covalent binding. As biocatalysts with the highest activity recovery yields, LBC immobilized by covalent binding with epichlorohydrin without (203%) and with PIL (250%), was assessed by the following the hydrolysis reaction of olive oil and characterized biochemically (Michaelis⁻Menten constant, optimum pH and temperature, and operational stability). Further, the potential transesterification activity for three substrates: sunflower, soybean, and colza oils, was also determined, achieving a conversion of ethyl esters between 70 and 98%. The supports and the immobilized lipase systems were characterized using Fourier transform infrared spectra (FTIR), scanning electron microscopy (SEM), elemental analysis, and thermogravimetric (TG) analysis.

A cold and organic solvent tolerant lipase produced by Antarctic strain Rhodotorula sp. Y-23.

Psychrotolerant yeast Rhodotorula sp. Y-23 was isolated from the sediment core sub-samples of Nella Lake, East Antarctica. Isolate was screened for lipase production using plate assay method followed by submerged fermentation. Production optimization revealed the maximum lipase production by using palmolein oil (5% v/v), pH 8.0 and inoculum size of 2.5% v/v at 15 °C. The potential inducers for lipase were 1% w/v of galactose and KNO3 , and MnCl2 (0.1% w/v). Final productions with optimized conditions gave 5.47-fold increase in lipase production. Dialyzed product gave a purification fold of 5.63 with specific activity of 26.83 U mg-1 and 15.67% yields. This lipase was more stable at pH 5.0 and -20 °C whereas more activity was found at pH 8.0 and 35 °C. Stability was more in 50 mM Fe3+ , EDTA-Na (20 mM), sodium deoxycholate (20 mM), H2 O2 (1% v/v), and almost all organic solvents (50% v/v). Tolerance capacity at wider range of pH and temperature with having lower Km value i.e., 0.08 mg ml-1 and higher Vmax 385.68 U mg-1 at 15 °C make the studied lipase useful for industrial applications. Besides this, the lipase was compatible with commercially available detergents, and its addition to them increases lipid degradation performances making it a potential candidate in detergent formulation.

High-level expression and characterization of solvent-tolerant lipase.

In this study, the coding sequence of the lipase from Proteus sp. SW1 was optimized via codon optimization and subjected to expression in Pichia pastoris GS115. The maximum enzyme yield was 387 mg/L in the supernatants of the shake-flask culture. The purified recombinant lipase exhibited a specific activity of 130 U/mg toward p-nitrophenyl Laurate. Its optimum pH and temperature were 8.0 and 40°C, respectively. It was highly stable and even activated in water-miscible solvents, showing over 102% residual activity after 24 h incubation in ethanol, acetone, isopropanol and acetonitrile. In addition, the enzyme showed promoted activity with the increasing concentrations of methanol/ethanol and exhibited the maximum activity at 80%. In a solvent-free system for biodiesel synthesis with a one-step addition of methanol, the recombinant lipase displayed a 87% conversion rate toward palm oil at the high water content of 80%. The highly improved expression level and activity of the recombinant lipase may contribute to enable its commercial-scale production, and the unique properties would make it a particularly promising biocatalyst for biodiesel production in the future.

Improved Performance of Magnetic Cross-Linked Lipase Aggregates by Interfacial Activation: A Robust and Magnetically Recyclable Biocatalyst for Transesterification of Jatropha Oil.

Lipases are the most widely employed enzymes in commercial industries. The catalytic mechanism of most lipases involves a step called "interfacial activation". As interfacial activation can lead to a significant increase in catalytic activity, it is of profound importance in developing lipase immobilization methods. To obtain a potential biocatalyst for industrial biodiesel production, an effective strategy for enhancement of catalytic activity and stability of immobilized lipase was developed. This was performed through the combination of interfacial activation with hybrid magnetic cross-linked lipase aggregates. This biocatalyst was investigated for the immobilization of lipase from Rhizomucor miehei (RML). Under the optimal conditions, the activity recovery of the surfactant-activated magnetic RML cross-linked enzyme aggregates (CLEAs) was as high as 2058%, with a 20-fold improvement over the free RML. Moreover, the immobilized RML showed excellent catalytic performance for the biodiesel reaction at a yield of 93%, and more importantly, could be easily separated from the reaction mixture by simple magnetic decantation, and retained more than 84% of its initial activities after five instances of reuse. This study provides a new and versatile approach for designing and fabricating immobilized lipase with high activation and stability.

Functional Elucidation of Nemopilema nomurai and Cyanea nozakii Nematocyst Venoms' Lytic Activity Using Mass Spectrometry and Zymography.

BACKGROUND: Medusozoans utilize explosively discharging penetrant nematocysts to inject venom into prey. These venoms are composed of highly complex proteins and peptides with extensive bioactivities, as observed in vitro. Diverse enzymatic toxins have been putatively identified in the venom of jellyfish, Nemopilema nomurai and Cyanea nozakii, through examination of their proteomes and transcriptomes. However, functional examination of putative enzymatic components identified in proteomic approaches to elucidate potential bioactivities is critically needed. METHODS: In this study, enzymatic toxins were functionally identified using a combined approach consisting of in gel zymography and liquid chromatography tandem mass spectrometry (LC-MS/MS). The potential roles of metalloproteinases and lipases in hemolytic activity were explored using specific inhibitors. RESULTS: Zymography indicated that nematocyst venom possessed protease-, lipase- and hyaluronidase-class activities. Further, proteomic approaches using LC-MS/MS indicated sequence homology of proteolytic bands observed in zymography to extant zinc metalloproteinase-disintegrins and astacin metalloproteinases. Moreover, pre-incubation of the metalloproteinase inhibitor batimastat with N. nomurai nematocyst venom resulted in an approximate 62% reduction of hemolysis compared to venom exposed sheep erythrocytes, suggesting that metalloproteinases contribute to hemolytic activity. Additionally, species within the molecular mass range of 14-18 kDa exhibited both egg yolk and erythrocyte lytic activities in gel overlay assays. CONCLUSION: For the first time, our findings demonstrate the contribution of jellyfish venom metalloproteinase and suggest the involvement of lipase species to hemolytic activity. Investigations of this relationship will facilitate a better understanding of the constituents and toxicity of jellyfish venom.

One-Step Partially Purified Lipases (ScLipA and ScLipB) from Schizophyllum commune UTARA1 Obtained via Solid State Fermentation and Their Applications.

Lipases with unique characteristics are of value in industrial applications, especially those targeting cost-effectiveness and less downstream processes. The aims of this research were to: (i) optimize the fermentation parameters via solid state fermentation (SSF); and (ii) study the performance in hydrolysis and esterification processes of the one-step partially purified Schizophyllum commune UTARA1 lipases. Lipase was produced by cultivating S. commune UTARA1 on sugarcane bagasse (SB) with used cooking oil (UCO) via SSF and its production was optimized using Design-Expert® 7.0.0. Fractions 30% (ScLipA) and 70% (ScLipB) which contained high lipase activity were obtained by stepwise (NH4)2SO4 precipitation. Crude fish oil, coconut oil and butter were used to investigate the lipase hydrolysis capabilities by a free glycerol assay. Results showed that ScLipA has affinities for long, medium and short chain triglycerides, as all the oils investigated were degraded, whereas ScLipB has affinities for long chain triglycerides as it only degrades crude fish oil. During esterification, ScLipA was able to synthesize trilaurin and triacetin. Conversely, ScLipB was specific towards the formation of 2-mono-olein and triacetin. From the results obtained, it was determined that ScLipA and ScLipB are sn-2 regioselective lipases. Hence, the one-step partial purification strategy proved to be feasible for partial purification of S. commune UTARA1 lipases that has potential use in industrial applications.

Optimisation of combi-lipases from Aspergillus niger for the synergistic and efficient hydrolysis of soybean oil.

The enzymatic properties of four lipases (A, B, C and D) from different strains of Aspergillus niger, were investigated, and a 3-factor mixture design and triangular surface analysis were performed to screen the optimal combi-lipase by observing synergistic effects. Lipases B and D differed in optimal pH, temperature and substrate specificity. A combi-lipase with 31.2% lipase B and 68.8% lipase D (w/w, equal to units of 30.36% and 69.64%) exhibited optimal hydrolytic activity on soybean oil, which exceeded the sum of the combined activities of individual lipases (P < 0.05). Free fatty acid from the hydrolyzed soybean oil indicated that the synergistic effect of the combi-lipase resulted from the different fatty acid specificities of the two lipases. Overall, combi-lipase afforded an effective route for the application of lipase enzymes to animal feeds.

Isolation and characterization of a thermostable lipase from Bacillus thermoamylovorans NB501.

Two thermophilic bacterial strains, Bacillus thermoamylovorans NB501 and NB502, were isolated from a high-temperature aerobic fermentation reactor system that processes tofu refuse (okara) in the presence of used soybean oil. We cloned a lipase gene from strain NB501, which secretes a thermophilic lipase. The biochemical characteristics of the recombinant enzyme (Lip501r) were elucidated. Lip501r is monomeric in solution with an apparent molecular mass of 38 kDa on SDS-PAGE. The optimal pH and apparent optimal temperature of Lip501r were 8 and 60°C, respectively. Supplementation of 5 mM Ca2+ enhanced the thermostability, and the enzyme retained 56% of its activity for 30 min at 50°C. Lip501r was active on a wide range of substrates with different lengths of p-nitrophenyl (pNP) esters, and showed a remarkably higher activity with pNP-myristate. The Km and Vmax values for pNP-butyrate in the presence of 5 mM CaCl2 were 1.8 mM and 220 units/mg, respectively. The possible industrial use of the thermophilic lipase in modifying edible oil was explored by examining the degradation of soybean oil. A TLC analysis of the degraded products indicated that Lip501r is an 1,3-position specific lipase. A homology modeling study revealed that helix α6 in the lid domain of NB501 lipase was shorter than that of lipases from the Geobacillus group.

Molecular and enzymatic characterization of alkaline lipase from Bacillus amyloliquefaciens E1PA isolated from lipid-rich food waste.

Bacillus amyloliquefaciens E1PA is a lipase-producing strain that was originally isolated from lipid-rich food waste, and the production of its lipase was found to be induced by vegetable oils. The E1PA lipase was successfully expressed and secreted in a heterologous Escherichia coli host and was ultimately purified. The conserved pentapeptide motif Ala-His-Ser-Met-Gly was observed at positions 108-112. The purified recombinant lipase was stable over a pH range of 4.0-11.0 at 40 °C and exhibited maximal activity at pH 10. The recombinant E1PA lipase hydrolyzed a wide range of acyl esters (C4-C18). However, the highest activity (3.5 units mg(-1)) was observed when the p-nitrophenyl ester of myristate (C14) was used as a substrate. Compared to the lipases produced by Bacillus spp., the E1PA lipase displayed a structural molecular mass excluding the leader sequence (19.22 kDa) and a pI (9.82) that were similar to those reported for B. amyloliquefaciens lipases and lipase subfamily I.4 but that were quite distinct from those of lipase subfamily I.5 (approximately 43 kDa, pI 6). These results suggested that Bacillus lipases are closely related. Although the recombinant E1PA lipase digested only certain oils, the wild-type E1PA lipase degraded a variety of oils, including blended and re-used cooking oils. The recombinant and wild-type forms of the E1PA lipase were able to digest heterogeneous lipid-rich food waste at similar levels; this result suggests that this lipase can function even when it solely consists of its structural enzyme component. The enzyme exhibited lipid hydrolysis ability as either an intracellular domain of the recombinant protein or an extracellular domain secreted by the E1PA strain. However, the recombinant lipase showed higher activity than the wild-type E1PA lipase, indicating that the recombinant protein from E. coli possessed effective lipase activity. Thus, the inducible alkaline E1PA lipase exhibited the ability to act on a broad spectrum of substrates, and the effective form produced in the heterogeneous host can be further developed for several applications, such as biodiesel production and lipase production.

Utilization of coconut oil cake for the production of lipase using Bacillus coagulans VKL1.

The overproduction of enzymes was performed by manipulating the medium components. In our study, solvent-tolerant thermophilic lipase-producing Bacillus coagulans was isolated from soil samples and a stepwise optimization strategy was employed to increase the lipase production using coconut oil cake basal medium. In the first step, the influence of pH, temperature, carbon source, nitrogen source and inducers on lipase activity was investigated by the One-Factor-At-A-Time (OFAT) method. In the second step, the three significant factors resulted from OFAT were optimized by the statistical approach (CCD).The optimum values of olive oil (0.5%), Tween 80 (0.6%) and FeSO4 (0.05%) was found to be responsible for a 3.2-fold increase in the lipase production identified by Central Composite Design.

Utilization of coconut oil mill waste as a substrate for optimized lipase production, oil biodegradation and enzyme purification studies in Staphylococcus pasteuri

Background Oil and grease laden wastewaters pose hindrance to the treatment units and further threaten the receiving water bodies. Lipase-producing microbial strains are increasingly being exploited for the remediation of such effluents. Results When bacterial strains isolated from oil mill effluent were screened for their lipolytic activity, two isolates, COM-4A and COM-6B showed significant extracellular lipase activity. They were identified to be Staphylococcus pasteuri and Bacillus subtilis, respectively. S. pasteuri COM-4A was cultivated in nutrient media based on coconut oil mill waste (CMW), in which it showed good growth at concentrations up to 20 g/L. While growing in such media, it was capable of producing lipase and other important extracellular hydrolytic enzymes. Furthermore, the isolate was able to effectively biodegrade the CMW supplemented in the medium. Applying the Box Behnken Design of Response Surface Methodology, lead to a 1.4-fold increase in both lipase production and oil removal by the isolate. The lipase was purified 9.02-fold and the molecular weight of the monomeric enzyme was deduced to be around 56 kDa. Characterization of the enzyme revealed it to be alkaliphilic and moderately thermophilic in nature, with pH and temperature optima of 9.0 and 50°C, respectively. The enzyme was also quite stable in the presence of water-miscible organic solvents. Conclusion Hence, the COM-4A lipase could be considered to be suitable for a variety of industrial applications such as in detergent formulations and in biodiesel production as well, apart from the possibility of applying it for bioremediation of fat and oil contaminants.

A new thermostable and organic solvent-tolerant lipase from Staphylococcus warneri; optimization of media and production conditions using statistical methods.

A new thermostable and solvent-tolerant lipase was isolated from newly isolated Staphylococcus warneri from oil-contaminated soil. Optimization of the fermentation media for production of thermostable and organic solvent-tolerant lipase was carried out using two statistical methods, i.e., Plackett-Burman design (PBD) and central composite design (CCD) were used for the optimization of the media components. PBD was used to efficiently select important medium components affecting the lipase production. Out of 15 medium components screened, four components, i.e., olive oil, peptone, maltose, and K2HPO4 were found to contribute positively to lipase production. CCD and response surface methodology (RSM) were used to determine the optimum levels of the selected components using Design-Expert 8.0 software. Production medium with olive oil (1.45 %), peptone (0.28 %), maltose (0.054 %), and K2HPO4 (0.091 %) was optimized with a maximum lipase production of 10.43 IU/ml/min. Similarly, production conditions for the lipase production were optimized by using CCD and RSM. Optimized conditions were found to have an incubation temperature of 55 °C, medium pH of 8.0, agitation of 120 rpm, and inoculum volume of 2 %. RSM revealed the maximum lipase production of 17.21 IU/ml using these optimized production conditions. Crude lipase showed enhanced activity in organic solvents such as diethyl ether, hexane, and cyclohexane.

Production, optimization, and partial purification of lipase from Pseudomonas sp. strain BUP6, a novel rumen bacterium characterized from Malabari goat.

This study introduces a novel bacterium-Pseudomonas sp. strain BUP6-isolated from the rumen of the Malabari goat with efficiency for producing lipase. It showed significant production of lipase when grown in a newly designed basal medium, supplemented with vegetable oil. Suitability of five vegetable oils such as groundnut oil, coconut oil, olive oil, sunflower oil, and palm oil as inducer for the production of lipase was examined, and groundnut oil supported the highest production of lipase (96.15 U/mL). Various physical parameters required for the maximum production of lipase were statistically optimized. Plackett-Burmann design was employed to study the interactive effects of physical parameters and found that temperature, agitation, and pH effected the production of lipase significantly. The optimum conditions for lipase production (37 °C, 200 rpm, and pH 6.9) were detected by Box-Behnken design and response surface methodology, which resulted in the 0.3-fold increase (i.e., 126 U/mL) of the lipase activity over the unoptimized condition. The apparent molecular mass of partially purified lipase was 35 kDa, as judged by SDS-PAGE; the activity of lipase was also confirmed by native PAGE. Thus, this study focuses on the need for the exploitation of rumen microbes for the production of industrially significant and human-friendly biomolecules to meet the future needs.

Potential pancreatic lipase inhibitory activity of an endophytic Penicillium species.

Pancreatic lipase (PL) is considered as one of the safest target for diet-induced anti-obesity drug development. Orlistat is the only PL inhibitor approved for anti-obesity treatment till date. In the process of exploration of new PL inhibitors, we have screened culture filtrates of 70 endophytic fungi of medicinal plants using qualitative as well as quantitative in-vitro PL assays. The qualitative assays indicated potential PL inhibition in only three isolates, namely #57 TBBALM, #33 TBBALM and #1 CSSTOT. Only ethyl acetate extracts of the culture filtrates of these isolates exhibited the PL inhibition. #57 TBBLAM ethyl acetate extract of culture filtrate exhibited potential PL inhibition with an IC50 of 3.69 µg/ml which was comparable to the positive control, i.e. Orlistat exhibiting IC50 value of 2.73 µg/ml. Further molecular phylogenetic tools and morphological studies were used to identify the isolate #57 TBBALM as Penicillium species.

Lipolytic potential of Aspergillus japonicus LAB01: production, partial purification, and characterisation of an extracellular lipase.

Lipolytic potential of Aspergillus japonicus LAB01 was investigated by describing the catalytic properties and stability of a secreted extracellular lipase. Enzyme production was considered high under room temperature after 4 days using sunflower oil and a combination of casein with sodium nitrate. Lipase was partially purified by 3.9-fold, resulting in a 44.2% yield using ammonium sulphate precipitation (60%) quantified with Superose 12 HR gel filtration chromatography. The activity of the enzyme was maximised at pH 8.5, and the enzyme demonstrated stability under alkaline conditions. The optimum temperature was found to be 45°C, and the enzyme was stable for up to 100 minutes, with more than 80% of initial activity remaining after incubation at this temperature. Partially purified enzyme showed reasonable stability with triton X-100 and was activated in the presence of organic solvents (toluene, hexane, and methanol). Among the tested ions, only Cu(2+), Ni(2+), and Al(3+) showed inhibitory effects. Substrate specificity of the lipase was higher for C14 among various p-nitrophenyl esters assayed. The KM and V max values of the purified enzyme for p-nitrophenyl palmitate were 0.13 mM and 12.58 umol/(L·min), respectively. These features render a novel biocatalyst for industrial applications.