Pectin-crosslinked-guar gum/SPION nanocomposite hydrogel for adsorption of m-cresol and o-chlorophenol

Pectin-crosslinked-guar gum/superparamagnetic iron oxide (Pc-cl-GG/SPION) nanocomposite hydrogel have been fabricated through co-precipitation/polymerization method. During this process, methylenebisacrylamide was used as a sole cross linker and it plays a vital role for the enhancement of mechanical stability of the nanocomposite hydrogel. This magnetic nanocomposite hydrogel was characterized using various techniques such as Fourier-Transform Infrared (FTIR) Spectroscopy, X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) Transmission Electron Microscopy (TEM) and Vibrating Sample Magnatometery (VSM). The prepared nanocomposite hydrogel was subjected to adsorption of organic pollutants from aqueous system. Experimental results indicated that Langmuir isotherm fitted best to the adsorption of MC and OCP onto Pc-cl-GG/SPION nanocomposite hydrogel. Maximum adsorption capacity of Pc-cl-GG/SPION nanocomposite hydrogel has been found to be 176.1 and 75.6 mg/g for m-cresol and o-chlorophenol, respectively.     

Evaluation of adsorption capacities of nanocomposites prepared from bean starch and montmorillonite

To date, many efforts have been made in order to develop novel cost-efficient materials that can be used to remove heavy metal ions from aqueous solution. The aim of this work was to evaluate the adsorption capacity of nanocomposites prepared from starch and sodium montmorillonite (starch/Na-MMT). To this end, nanocomposites with different starch-to-nanoclay ratio (SN) of 5:1, 10:1 and 10:3 were prepared by intercalation technique in acetic acid solution and used for nickel and cobalt uptake. The characterization techniques of Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) were conducted to determine physicochemical and morphological properties of nanocomposites as well as bean starch. The initial concentration of metal ions, pH and SN ratios were varied to assess how well the starch/Na-MMT nanocomposites could remove cobalt and nickel from aqueous solutions. Experimental results were used to calculate parameters of the Langmuir and Freundlich isotherms. It was found that pH = 4.5, C_o = 100 ppm (metal concentration in solution), and SN = 10:1 were the most suitable conditions based on the removal yield (97.1%) and adsorptive favourability for nickel ions. For cobalt, the highest removal yield (78.07%) was achieved using pH = 6, C_o = 140 ppm and SN = 10:3. The fitting of the data to the Langmuir and Freundlich isotherms indicated a multilayer adsorption process for both heavy metals. These results showed that the nanocomposite starch/Na-MMT exhibited attractive adsorption properties for its application during wastewater remediation. The incorporation of Na-MMT in the bean starch matrix is strongly encouraged for nickel uptake due to the adsorption efficiencies increase by 35% compared to the unmodified starch.     

Preparation and characterization of biochar derived from the fruit seed of Cedrela odorata L and evaluation of its adsorption capacity with methylene blue

Biochar has proven to be an effective tool in several aspects of environmental management; as well as many other applications. Herein we report biochar derived from the capsule-like interior of the seeds of Cedrela odorata L, prepared via pyrolysis at 400 °C. The biochar was characterized using: Elemental analysis, Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), X-ray diffraction (XRD), Thermal gravimetric analysis (TGA) and Raman Spectroscopy. Results demonstrate that a biochar of high thermal stability and porosity was obtained, with surface functional groups that enhance the adsorption process. Equilibrium adsorption data were consistent with the Langmuir isotherm model, indicating surface homogeneity, with maximum adsorption capacity of 158.8 mg/g. These results demonstrate that the biochar is an efficient adsorbent for the removal of MB dye from aqueous solution; and suggests its utility for further exploration in removing heavy metals from water as well as its use as a solid support in catalysis.     

Physicochemical properties and anticoagulant activity of polyphenols derived from Lachnum singerianum

In this study, polyphenols (LSP) were obtained from the fermentation broth of Lachnum singerianum. Two fractions were isolated by Sephadex LH-20 chromatographic column, and the primary fraction (LSP-1) was collected. The comprehensive physicochemical properties of phenolic acids and polyhydroxy phenolic compounds of LSP-1 were determined by UV-visible spectroscopy, Fourier transform infrared spectroscopy, and gas chromatography–mass spectrometry. Results of anticoagulant activity assay in vitro showed that LSP-1 could lengthen prothrombin time, activated partial thromboplastin time, and thrombin time of mouse plasma. In addition, anticoagulant activity results in vivo showed that high dose of LSP-1 could significantly prolong bleeding time, coagulation time, prothrombin time, activated partial thromboplastin time, and thrombin time of hypercoagulable mice induced by adrenaline, reduce the content of fibrinogen and enhance antithrombin III activity. All results indicated that the LSP-1 could serve well as an anticoagulant, and might be used as a potential natural drug candidate for thrombosis.     

Physicochemical properties and skin permeation of Span 60/Tween 60 niosomes of ellagic acid

Ellagic acid (EA) is a potent antioxidant phytochemical substance which has limitation to use due to its poor biopharmaceutical properties, low solubility and low permeability. The aim of the present study was to develop niosomal formulations obtained from the mixture of Span 60 and Tween 60 that could encapsulate EA for dermal delivery. The EA-loaded niosomes were prepared with 1:0, 2:1, 1:1, 0:1 Span 60 and Tween 60, using polyethylene glycol 400 (PEG 400), propylene glycol (PG) or methanol (MeOH) as a solubilizer. The influence of formulations on vesicle size, entrapment efficiency and stability of EA-loaded niosomes was investigated. It was found that all ratios of surfactants could produce EA-loaded niosomes when using 15% (v/v) PG, 15% (v/v) PEG 400 or 20% (v/v) MeOH. The niosomes were spherical multilamellar vesicles showing the localization of EA in the vesicles. The vesicle sizes of the niosomes after extrusion were 124-752 nm with PI less than 0.4. The percentages of entrapment efficiency (% E.E.) of all EA-loaded niosomes varied between 1.35% and 26.75% while PEG 400 niosomes gave the highest % E.E. The most stable and highest entrapped formulation was 2:1 Span 60 and Tween 60 niosomes. Additionally, the in vitro skin permeation revealed that penetration of EA from the niosomes depended on vesicle size, the amount of EA entrapped and the added solubilizers which could act as a permeation enhancer. From skin distribution study, the EA-loaded niosomes showed more efficiency in the delivery of EA through human epidermis and dermis than EA solution. The results indicated that the Span 60 and Tween 60 niosomes may be a potential carrier for dermal delivery of EA.     

Concurrent removal of Cr(III), Cu(II), and Pb(II) ions from water by multifunctional TiO2/Alg/FeNPs beads

The use of multifunctional materials for water remediation is a modern approach where adsorption phenomena and heterogeneous photocatalysis can be applied for the removal of pollutants. Since the ideal remediation system should be able to remove both organic and inorganic pollutants, a crucial aspect to consider is the knowledge of operational parameters affecting the removal process, especially when heavy metal ions are present in concoction as in real systems. Given the proven efficiency of multifunctional TiO₂/Alg/FeNPs magnetic beads for the removal of model organic pollutants, this study investigated the possibility to exploit such system also for the removal of mixed heavy metals (MHM), specifically Cr(III), Cu(II), and Pb(II) ions, under ultraviolet irradiation at a wavelength of 254 nm. After a preliminary screening on the optimal catalyst loading, operating parameters such as the initial concentration of metal ions, contact and irradiation time, and pH were investigated to optimize the removal of metal ions using response surface methodology (RSM) via Box–Behnken design. Starting from a MHM solution containing 44 ppm of each metal ion, the removal of Pb(II), Cr(III), and Cu(II) ions in the aqueous solution was nearly completed (>98.4%) for all three ions within 72 min of irradiation at almost neutral pH (pH = 6.8). The stability of TiO₂/Alg/FeNPs was confirmed by retrieving and reusing the beads in three consecutive cycles of heavy metals removal without observing significant changes in catalyst efficiency.     

Antibacterial activity and in vivo wound healing potential of phenolic extracts from jaboticaba skin

In this study, different phenolic extracts were obtained from the jaboticaba skin meal (JSM), whose phenolic compounds were characterized and their antibacterial activities were assessed. Moreover, the activity of lyophilized ethanolic extract of jaboticaba skin (EEJS) on wound healing was analyzed in rats. The JSM phenolic extracts were obtained in four ways: aqueous, methanolic, ethanolic, and acetone extracts. The phenolic compounds were characterized in these extracts by high‐performance liquid chromatography, and their antibacterial activities were evaluated. The in vivo experiment was divided into four groups and received the following treatments: G1—silver sulfadiazine (positive control); G2—EEJS at 10%; G3—EEJS at 5%, and G4—EEJS at 2.5%. The aqueous extract did not inhibit the growing of any bacterium. The ethanolic, acetone, and methanolic extracts inhibited the growing of all bacteria tested at the concentrations of 1.25%, 2.50%, and 5.00%, respectively. The ethanolic extract was the one that showed the highest bacterial inhibition potential and the highest contents of phenolic compounds, especially of catechin, epicatechin gallate, and epicatechin. The G3 and G4 treatments presented faster wound healing compared to the G1 one, as it promoted a less intense inflammatory reaction and full closure of the wounds at an accelerated rate.     

Sustained release of platelet-derived growth factor and vascular endothelial growth factor from silk/calcium phosphate/PLGA based nanocomposite scaffold

To exploit the therapeutic potential of growth factors in tissue regeneration, it is necessary to design a porous scaffold in order to concurrently accommodate cells and release angiogenic factors in a controlled manner. In an attempt to address these issues, we developed a nanocomposite scaffold based on silk/calcium phosphate/PLGA by freeze-drying and electrospinning in order to control the release of platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF). The highly porous scaffold possessed appropriate chemical and physical structure as confirmed by FTIR, XRD, SEM, and Zeta potential analysis. Furthermore, the incorporation of PDGF and VEGF in the scaffold was confirmed using Raman spectroscopy while their bioactivity was maintained by 82% and 89% for up to 28 days, respectively. The release of PDGF was slower than VEGF as respected. Additionally, the scaffold could promote proliferation, alkaline phosphatase production and attachment of human osteoblast cells. Histological examination established new bone matrix formation with neovascularization in the angiogenic factors loaded scaffold after 10 weeks of implantation in rabbit model. Finally, it was considered that the fabricated nanocomposite could be useful for bone tissue engineering applications.     

罗非鱼皮胶原蛋白改变菌体形态和破坏细胞壁实现抑菌作用研究

摘要：目的:探讨罗非鱼皮酶溶性胶原蛋白(Pepsin soluble collagen peptide from Tilapia skin, PSCPT)、罗非鱼皮酸溶性胶原蛋白(Acid soluble collagen peptide from Tilapia skin, ASCPT)的制备及抗菌性能。方法: 罗非鱼皮经浸提、离心、透析和冷冻干燥等步骤获得干燥的PSCPT、ASCPT。采用含有PSCPT或ASCPT的胰蛋白胨大豆肉汤培养基振荡培养大肠杆菌、金黄色葡萄球菌、铜绿假单胞菌和白色念珠菌,定时测定细菌培养液的吸光度值、菌数、菌体细胞液电导率和细菌的形态特征。结果: 以牛胶原蛋白(Bovine skin collagen, BSC)为对照,PSCPT、ASCPT对大肠杆菌、金黄色葡萄球菌、铜绿假单胞菌、白色念珠菌均有不同程度的生长抑制作用,抑制率从22.97%±2.35%到65.21%±6.42%,其中PSCPT抑制铜绿假单胞菌作用显著,抑制率达到65.21%±6.42%;ASCPT抑制大肠杆菌作用微弱,抑制率只有22.97%±2.35%。血球计数板法得到的抑菌效果类似吸光度值得到的结果,但是抑制率存在差别。PSCPT、ASCPT造成大肠杆菌、金黄色葡萄球菌、铜绿假单胞菌、白色念珠菌的菌体细胞液电导率从36.42±1.35μs/cm变化到185.80±4.70 μs/cm,其中PSCPT使铜绿假单胞菌的电导率低至36.42±1.35μs/cm,ASCPT使白色念珠菌的电导率达到185.80±4.70 μs/cm。电镜下观察到抑菌率高和电导率低的菌株出现菌体变形和细胞壁破裂等现象。结论：与BSC相比,PSCPT、ASCPT从细菌抑制率、菌体细胞液电导率和细菌的形态特征体现出一定的抑菌特性。     

Dermatotoxicity of oral cadmium is strain-dependent and related to differences in skin stress response and inflammatory/immune activity

Adverse effects of non-occupational exposure to cadmium (Cd) are increasingly acknowledged. Since our previous study has showed that orally acquired Cd affects skin, the contribution of genetic background to dermatotoxicity of oral cadmium was examined in two rat strains, Albino Oxford (AO) and Dark Agouti (DA), which differed in response to chemicals. While similar accumulation of Cd in the skin of both strains was noted, the skin response to the metal differed. DA rat individuals mounted antioxidant enzyme defense in the skin already at lower Cd dose, in contrast to AO rats which reacted to higher metal dose solely (and less pronounced), implying higher susceptibility of DA strain to Cd dermatotoxicity. Epidermal cells from both strains developed stress response, but higher intensity of antioxidant response in AO rats implied this strain`s better ability to defend against Cd insult. Cd induced epidermal cells’ proinflammatory cytokine response only in DA rats. Increased IL-10 seems responsible for the lack of response in AO rats. Differences in the pattern of skin/epidermal cell responsiveness to cadmium give a new insight into repercussion of genetic variability to dermatotoxicity of orally acquired cadmium, bearing relevance for variations in the link between dietary cadmium and inflammation-based skin pathologies.     

蟾皮化学成分的分离与结构鉴定

蟾皮为蟾蜍科动物中华大蟾蜍Bufo bufo gargarizans Cantor的干燥皮，在我国民间多用来治疗原发性肝癌、肺癌、肠癌等，其水溶性成分制剂华蟾素注射液临床上用于消化道中晚期癌症，疗效确切，体外抗肿瘤活性筛选也表明蟾皮水提取物对结肠癌细胞HCT-8、肺癌细胞A-549生长均有明显的抑制作用。为了阐明其活性成分，对其水溶性成分进行了系统研究，采用Sephadex LH-20、硅胶柱色谱结合结晶法，从其水提物中分离得到6个化合物，分别鉴定为4-氨基-3-羟甲基-环辛酰胺骈四氢-α-呋喃酮(蟾蜍环酰胺B，I)、蟾蜍环酰胺C(II)、蟾蜍噻咛(III)、去氢蟾蜍色氨氢溴酸盐(IV)、辛二酸(V)和丁二酸(VI)，其中化合物I和II为新化合物。     

Isolation and preliminary characterization of a 22-kDa protein with trypsin inhibitory activity from toad Bufo andrewsi skin.

A novel trypsin inhibitor termed BATI was purified to homogeneity from the skin extracts of toad Bufo andrewsi by successive ion-exchange, gel-filtration and reverse-phase chromatography. BATI is basic single chain glycoprotein, with apparent molecular weight of 22 kDa in SDS-PAGE. BATI is a thermal stable competitive inhibitor and effectively inhibits trypsin's catalytic activity on peptide substrate with the inhibitor constant (K(i)) value of 14 nM and shows no inhibitory effect on chymotrypsin, thrombin and elastase. The N-terminal sequence of BATI is EKDSITD, which shows no similarity with other known trypsin inhibitors.     

Anticancer activity of a low immunogenic protein toxin (BMP1) from Indian toad (Bufo melanostictus, Schneider) skin extract

Earlier, a protein (BMP1, MW-79kDa) had been isolated from Indian toad (Bufo melanostictus) skin aqueous extract possessed anticancer activity against EAC bearing mice (Bhattacharjee et al., 2011). In the present study, the anti-proliferative and apoptogenic activities of BMP1 have been evaluated in leukemic (U937 and K562) and hepatoma (HepG2) cells. BMP1 dose dependently inhibited U937 and K562 cell growth having IC₅₀ values of 49 μg/ml and 30 μg/ml respectively. The anti-proliferative activity of BMP1 was observed in MTT assay, proliferating cell nuclear antigen (PCNA) expression and cell cycle arrest study. Flow-cytometric data revealed that BMP1 arrested cell cycle in U937 and K562 cells at Sub-G1 and G1 phases. The BMP1-induced dose dependent expressions of CDKIs (p21^cip1 and p27^kip1) and inhibition of CDK2 and PCNA expression in HepG2 cells support the inhibition of cell proliferation due to G1 arrest. BMP1-induced apoptosis analyzed by annexin-V binding study and the DNA fragmentation by comet assay were correlated with the sub-G1 arrest. The parallel induction of bax and p53 expression in HepG2 cells and the up-regulation of caspase 3 and caspase 9 due to BMP1 treatment indicated the involvement of p53-dependent intrinsic pathway of apoptosis. BMP1 was found to be low immunogenic in nature.     

Modifications of the bacterial reverse mutation test reveals mutagenicity of TiO2 nanoparticles and byproducts from a sunscreen TiO2-based nanocomposite

The bacterial reverse mutation test, recommended by the Organization for Economic Co-operation and Development (OECD) to determine genotoxicity of chemical compounds, has been recently used by several authors to investigate nanoparticles. Surprisingly, test results have been negative, whereas in vitro mammalian cell tests often give positive genotoxic responses. In the present study, we used the fluctuation test procedure with the Salmonella typhimurium strains TA97a, TA98, TA100 and TA102 to determine the mutagenic potential of TiO₂ nanoparticles (NP-TiO₂) and showed that, when it is used conventionally, this test is not suitable for nanoparticle genotoxicity assessment. Indeed, the medium used during exposure prevents electrostatic interactions between bacterial cells and nanoparticles, leading to false-negative responses. We showed that a simple pre-exposure of bacteria to NP-TiO₂ in a low ionic strength solution (NaCl 10 mM) at a pH below the nanoparticle isoelectric points (pH 5.5) can strongly improve the accuracy of the test. Thus, based on these improvements, we have demonstrated the genotoxicity of the engineered NP-TiO₂ tested and a NP-TiO₂ byproduct from a sunscreen nanocomposite. It was also shown that strain TA102 is more sensitive than the other strains, suggesting an oxidative stress-mediated mechanism of genotoxicity.     

香附醇提物抗神经炎症活性及化学成分分析

目的 香附抗神经炎症活性部位确定及成分分析。方法 基于脂多糖（LPS）诱导BV2细胞炎症模型,Griess法检测培养上清液中NO水平评价香附95%乙醇提取物（CR-95E,6.25、12.50、25.00、50.00 μg · mL^-1）、50%乙醇提取物（CR-50E,6.25、12.50、25.00、50.00、100.00 μg·mL^-1）、水提取物（CR-W,6.25、12.50、25.00、50.00、100.00 μg·mL^-1）的抗炎活性;ELISA试剂盒法考察活性部位对模型细胞上清液中肿瘤坏死因子-α（TNF-α）、白细胞介素-1β（IL-1β）和白细胞介素-6（IL-6）含量的影响;采用ELISA法检测上清液中犬尿氨酸途径激活关键酶吲哚胺2,3-双加氧酶（IDO）的含量变化;采用气相色谱-质谱联用（GC-MS）技术对CR-95E进行化学成分定性分析,与NIST MS search 2.0质谱检索数据库比对鉴定化合物结构。结果 与模型组比较,CR-95E在6.25～50.00 μg· mL^-1时可显著抑制LPS诱导BV2细胞释放NO（P＜0.001）,而CR-50E和CR-W无效,说明CR-95E具有确切的抗神经炎作用。与模型组比较,CR-95E可显著降低细胞上清液中炎症因子IL-1β、IL-6和TNF-α的含量（P＜0.05、0.01、0.001）,显著降低IDO的过量表达（P＜0.001）。GC-MS分析,从CR-95E中共鉴定了34个化合物,主要为萜烯类和酮类成分,相对质量分数由高到低依次为异长叶烯酮（19.47%）、石竹烯氧化物（4.98%）、喇叭烯氧化物（-II）（4.01%）、α-古芸烯（3.66%）等。结论 香附抗神经炎症活性部位为CR-95E,主要含有萜烯类和酮类成分等低极性成分,可通过抑制细胞NO和炎症因子的释放,抑制IDO过表达发挥抗神经炎症作用。     

Isolation and characterization of a trypsin inhibitor from the skin secretions of Kaloula pulchra hainana

Amphibian skin secretions contain many bioactive compounds. A trypsin inhibitor termed KPHTI was purified from the skin secretions of frog Kaloula pulchra hainana by successive ion-exchange and gel-filtration chromatography. KPHTI is a single chain glycoprotein, with an apparent molecular weight of 23 kDa in SDS-PAGE. It is a competitive inhibitor and effectively inhibits trypsin catalytic activity on peptide substrate with the inhibitor constant (K_i) value of 27 nM. KPHTI shows no inhibitory effect on chymotrypsin, thrombin, elastase, and subtilisin. The N-terminal sequence of KPHTI is DHEVTS, which shows no similarity with other known trypsin inhibitors. DTT apparently affected the inhibitory activity of KPHTI. But it was not sensitive to temperature and pH range, which suggested that it possessed stable trypsin inhibitory activity in natural environment, and maybe play an important role in against predators.     

Activities of seasonably variable caerulein and rothein skin peptides from the tree frogs Litoria splendida and Litoria rothii

Two species of tree frog of the genus Litoria, namely L. splendida and L. rothii have been reported to change the compositions of their host-defence skin peptide profiles in summer and winter. L. splendida produces the potent smooth muscle active caerulein [pEQDY(SO₃H)TGWMDF-NH₂] in summer, but in winter much of the caerulein is hydrolysed to the less active desulfated form; in addition, caerulein 1.2 [pEQDY(SO₃H)TGWFDF-NH₂] (which has only some 50% of the smooth muscle activity of caerulein) is released and acts via CCK2R. In contrast, Litoria rothii shows a most unexpected seasonal change of peptides. In summer it exudes caerulein together with a range of potent caerin antimicrobials and nNOS active peptides. In winter, none of the antibiotic or nNOS active caerin peptides are expressed. The major peptides produced by the skin glands in winter are caerulein 1.2 and rothein 1 (SVSNIPESIGF-OH). Like L. splendida, L. rothii has reduced the smooth muscle potency of caerulein by replacing it with caerulein 1.2. Rothein 1 is a lymphocyte proliferator acting via CCK2R. Activity testing and 2D NMR spectra of rothein 1 and some synthetic modifications indicate that both hydrophobic and hydrophilic interactions between rothein 1 and CCK2R are important.     

Apoptogenic activity and toxicity studies of a cytotoxic protein (BMP1) from the aqueous extract of common Indian toad (Bufo melanostictus Schneider) skin

A protein (BMP1) was purified from common Indian toad (Bufo melanostictus, Schneider) skin through DEAE cellulose ion exchange chromatography and high performance liquid chromatography. The molecular weight of the BMP1 was found to be 79 kDa. BMP1 (0.5 and 1 mg/kg/day, i.p.) significantly decreased the number of viable Ehrlich ascites carcinoma (EAC) cells, thereby increased the lifespan of EAC bearing mice (p < 0.001). MTT values reduced significantly with the treatment of BMP1 (0.5 and 1.0 mg/kg/day, i.p. for 3 days) on EAC cells indicated its antiproliferative activity. This was also supported by flow-cytometric data on the cell cycle arrest at G1 in EAC cells. BMP1 (1 mg/kg) reduced the solid tumor weight and volume of about three times further support the antiproliferative nature. Fluorescence and confocal microscopic study on EAC cells after BMP1 (0.5 mg/kg/day, i.p. for 3 days) treatment indicated certain features of apoptosis, like nuclear fragmentation, membrane blebbing, and vacuolization of cells. DNA fragmentation was clearly observed in alkaline comet assay. Apoptosis induced by BMP1 was further confirmed through flow-cytometric analysis of annexin-V binding study, sub-G1 arrest in the cell cycle and found to be mediated through caspase 3 dependent pathway. LD50 of BMP1 was found to be 12.2 mg/kg, i.p. in male Swiss albino mice. BMP1 treatment at 0.5 mg/kg and 1.0 mg/kg for 10 days did not alter any hematological and biochemical parameters in mice, but after 30 days of treatment produce significant rise in total leucocyte count, neutrophil percentage, serum urea, creatinine, GOT, LDH and decrease in lymphocyte percentage as compared to respective control. In conclusion, BMP1, a protein molecule isolated from Indian toad (B. melanostictus, Schneider) skin, showed antiproliferative and apoptogenic activity on EAC cancer cell with limited toxicity.     

Cytotoxic and apoptotic activity of essential oil from Ocimumviride towards COLO 205 cells

We investigated the apoptosis inducing effect of essential oil (EO) from aerial parts of Ocimumviride in human colorectal adenocarcinoma cells (COLO 205 cell line). The COLO 205 cells were exposed to 0.0125–0.1 μl/ml of EO for 24, 48 and 72 h. Growth inhibition was determined by sulphorhodamine B (SRB) assay. Double staining with acridine orange and ethidium bromide for nuclear changes was performed. Cell cycle analysis and change in mitochondrial membrane potential was quantified by flow cytometry. Subsequently, using annexin V/PI assay, the proportion of cells actively undergoing apoptosis was determined. Changes in DNA were observed by DNA ladder assay. Eventually the surface morphology of apoptotic cells was studied by scanning electron microscopy. EO is cytotoxic to COLO 205 cells in dose and time-dependent manner, as is evident by SRB assay. This observed cell death was due to apoptosis, as established by annexin V/PI assay, DNA ladder formation and scanning electron microscopy. Our results reveal that EO has apoptosis inducing effect against COLO 205 cells in vitro and is a promising candidate for further anti-cancer study.