GC-MS detection of chiral markers in cocoa beans of different quality and geographic origin

Fermented cocoa beans (Theobroma cacao L., Sterculiaceae) from different countries of origin (Ecuador, Ghana, Trinidad) and cocoa beans roasted under defined conditions (industrial roasting; 150-220 degrees C for 20 min, dry roasting in conventional oven) were analyzed for their contents of certain chiral hydroxy acids, catechins, and amino acids. Cocoa beans are fermented, dried, and industrially transformed by roasting for the production of chocolate, cocoa powders, and other cocoa-related products. Fermentation and roasting conditions influence the contents of chiral compounds such as hydroxy acids, amino acids, and polyphenols, depending on technological procedures as well as some technical parameters. The aim of this work was to check if the content and nature of the named chiral compounds present both in fermented and roasted cocoa beans could be related to the traditional parameters used to classify the variety of seeds and the degree of fermentation. The extent of racemization of amino acids in fermented cocoa beans was low while it slowly increased during roasting, depending on the temperature applied. L-lactic acid was always higher than the D-form while citric acid was generally the most abundant hydroxy acid detected in beans. A correlation was found between polyphenol content and degree of fermentation, while epimerization of (-)-epicatechin to (+)-catechin was observed during roasting. On the whole, results showed that several chiral compounds could be considered as good quality markers for cocoa seeds and cocoa-related products of different quality and geographic origin.     

Volatile components of cocoa with particular reference to glucosinolate products

The aroma volatiles of raw, fermented and roasted cocoa beans were extracted and concentrated to valid essences using well-established techniques. Analysis by GC and GC/MS showed at least 84 components of which 13 were identified for the first time as cocoa volatiles. In total, ca 5,66 and 65 μg of aroma components were obtained per g of raw, fermented and roasted cocoa beans, respectively. The most abundant groups of volatiles from fermented beans were alcohols (ca40%w/w of the total volatiles) and esters (ca 32%), whilst those from roasted beans were pyrazines (ca 40%) and aldehydes (ca 23%). Trimethyl- and tetramethylpyrazine were also detected in fermented beans, and it is suggested that they contribute to the noticeable cocoa/chocolate aroma of fermented unroasted beans. Phenylacetonitrile, benzyl isothiocyanate and benzyl thiocyanate were all identified amongst cocoa volatiles, together showing the presence of precursor benzylglucosinolate in cocoa. Glucosinolate products were detected in roasted beans, and it seems likely that the enzyme thioglucoside glucohydrolase survived the conditions of roasting. Benzyl thiocyanate was detected only in raw beans, showing that the glucosinolate ‘thiocyanate–forming factor’ did not withstand conditions of fermentation     

Stable Radical Content and Anti-Radical Activity of Roasted Arabica Coffee: From In-Tact Bean to Coffee Brew

The roasting of coffee beans generates stable radicals within melanoidins produced by non-enzymatic browning. Roasting coffee beans has further been suggested to increase the antioxidant (AO) capacity of coffee brews. Herein, we have characterized the radical content and AO capacity of brews prepared from Coffea arabica beans sourced directly from an industrial roasting plant. In-tact beans exhibited electron paramagnetic resonance signals arising from Fe³⁺, Mn²⁺ and at least three distinct stable radicals as a function of roasting time, whose intensity changed upon grinding and ageing. In coffee brews, the roasting-induced radicals were harboured within the high molecular weight (> 3 kD) melanoidin-containing fraction at a concentration of 15 nM and was associated with aromatic groups within the melanoidins. The low molecular weight (< 3 kD) fraction exhibited the highest AO capacity using DPPH as an oxidant. The AO activity was not mediated by the stable radicals or by metal complexes within the brew. While other non-AO functions of the roasting-induced radical and metal complexes may be possible in vivo, we confirm that the in vitro antiradical activity of brewed coffee is dominated by low molecular weight phenolic compounds.     

The antioxidant properties and microbial load of Moringa oleifera leaves dried using a prototype convective air-dryer

The recent COVID-19 pandemic resulted in major postharvest losses because most fresh produce could not be sold. Drying is an important thermal-based food preservation method which could have prolonged the shelf-life of these produce, but most drying technologies are costly, and cannot be afforded by small-time farmers. From this context, we were interested in evaluating the drying of Moringa oleifera leaves (MOL) using a low-cost self-built prototype convective-air dryer (CAD), alongside conventional drying methods for its antioxidant properties, microbial load and phytoconstituents. Results showed total polyphenol content was the highest (p < 0.05) in our CAD samples, and it retained among the highest total flavonoid content, total antioxidant capacity, total alkaloid content and DPPH radical scavenging activity. Furthermore, methanolic CAD extract presented lower coliform and yeast and mold count than the aqueous CAD extract. We also briefly explored MOL as a sanitizer where the microbial load of the methanolic extract was comparable (p > 0.05) with several commercial non-alcoholic sanitizers, indicating its commercialization potential as a bio-friendly sanitizer. Finally, using GC–MS, we are the first to report (best of our knowledge) on the presence of caprolactam, an important bio-medical field compound, in the CAD sample’s aqueous extract.     

Effects of processing methods on nutritional composition and antioxidant activity of mealworm (Tenebrio molitor) larvae

We examined the effects of different processing methods on the nutritional composition and antioxidant activity of mealworms. After processing with nine methods, we calculated the contents of protein, fat, ash, carbohydrate, minerals (P, Ca, K, Fe, Na), vitamin B group (B₁, B₂, B₃), moisture, and calories. When processed by freeze drying among freeze drying, hot air drying, oven broiling, roasting, pan frying, deep frying, boiling, steaming, and microwaving, the contents of protein, some minerals, and vitamins were the highest. The content of total minerals was lowest after deep frying, and those of vitamin B₁ and B₃ were the lowest after microwaving. Antioxidant activity was then evaluated using DPPH and ABTS radical scavenging assays. DPPH assays showed that microwaving, freeze drying, deep frying, steaming, boiling, and oven broiling of mealworms yielded scavenging activities of 20.9–29.0% at 2,000 μg/mL, which was similar to the activity level (22.7–33.2%) of 40–60 μM tocopherol. ABTS assays confirmed that only freeze‐dried mealworms at 2,000 μg/mL exhibited higher activity than 10 μM tocopherol. Interestingly, similar trends were found for antioxidant activity levels and total phenolic contents in mealworms.     

The stingless bee honey protects against hydrogen peroxide-induced oxidative damage and lipopolysaccharide-induced inflammation in vitro

Oxidative stress, DNA damage, and unresolved inflammation are the predisposing factors of many chronic and degenerative diseases, including cancer. Stingless bee honey (SBH) is recognized to have high medicinal value by traditional medicine practitioners and has been used to treat various illnesses traditionally. This study aimed to determine the antioxidant, anti-inflammatory, and genoprotective effects of SBH by using in vitro cell culture models. The sugar content, total phenolic content, radical scavenging activity, and ferric reducing antioxidant power (FRAP) of SBH were determined in this study. Then, the protective effect of SBH against hydrogen peroxide (H₂O₂)-induced cell death and DNA damage was studied by using WIL2-NS human lymphoblastoid cell line, while the lipopolysaccharide (LPS)-induced RAW 264.7 murine macrophages cell line was used to study the anti-inflammatory effects of SBH. Results from this present study showed that the major sugar contents of SBH were fructose (19.39 + 0.01%) and glucose (14.03 ± 0.03%). Besides, the total phenolic content, the radical scavenging activity, and the FRAP value of SBH were 15.38 ± 0.02 mg GAE/100 g of honey, 34.04 ± 0.21%, and 206.77 + 1.76 μM AAE/100 g honey respectively. Pretreatment with SBH protected WIL2-NS cells from H₂O₂-induced cell death and DNA damage (p < 0.001). Moreover, SBH was also able to attenuate the production of nitric oxide by inhibiting the expression of inducible nitric oxide synthase in LPS-induced RAW 264.7 cells (p < 0.001). In conclusion, SBH is rich in total phenolic content and possesses strong antioxidant, anti-inflammatory, and genoprotective properties. Our current findings suggest that SBH might be useful in the prevention and treatment of many diseases caused by oxidative stress and inflammation assuming the observed effects are also achievable in vivo.     

Evaluation of antioxidant activity of leafy vegetables and beans with myoglobin method

Key message

Antioxidant activity of seven leafy vegetables and four beans against five reactive oxygen species and reactive nitrogen species was clearly characterized with a protocol using myoglobin as a reporter probe.

Abstract

Antioxidant activity of seven leafy vegetables and four beans against peroxyl radical, hydroxyl radical, hypochlorite ion, and peroxynitrite ion has been measured using myoglobin as a reporter probe (myoglobin method). Conventional DPPH method was also used to evaluate antioxidant activity of the samples. Difference of activity against different reactive oxygen species (ROS) and reactive nitrogen species (RNS) was characterized by plotting the data in a 5-axe cobweb chart. This plot clearly showed the characteristics of the antioxidant activity of the leafy vegetables and the beans. The samples examined in this work were categorized into four groups. (1) The samples showed high antioxidant activity against all ROS and RNS: daikon sprout, spinach, Qing-geng-cai, and onion. (2) The samples showed high antioxidant activity against peroxyl radical: red bean and soy bean. (3) The samples showed high antioxidant against hypochlorite ion: broccoli floret, cabbage, and Chinese cabbage. (4) The samples showed weak antioxidant activity against all ROS and RNS: cowpea and common beans. Our protocol is probably useful to characterize antioxidant activity of the crops of different cultivars, the crops obtained in different growing environments and growing seasons, the crops harvested at different age, and the crops stored in the different conditions, as well as the changes of activity during cooking process of the crops.     

Antioxidant properties and phenolic profiling by UPLC-QTOF-MS of Ajwah,Safawy and Sukkari cultivars of date palm

Date palm (P. dactylifera) plays a vital role in ethnomedicinal practices in several parts of the world. There are over 2000 cultivars of date palm that differ in chemical composition and extent of bioactivity. The present study was undertaken to comparatively evaluate the antioxidant potential of three cultivars of date palm (Ajwah, Safawy and Sukkari) from Saudi Arabia and analyze their phenolic constituents in order to draw a rationale for their activity. Antioxidant activities of the date cultivars were evaluated by different quantitative methods including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical scavenging assay, total antioxidant capacity, reducing power, total phenolic (TPC), flavonoid (TFC) and tannin content (TTC), while qualitative phenolic composition was determined using ultra performance liquid chromatography coupled to quadropole time of flight mass spectrometry (UPLC-QTOF-MS). All the three date extracts showed good DPPH radical scavenging (IC₅₀ 103–177 μg/mL) and hydroxyl radical scavenging (IC₅₀ 1.1–1.55 mg/mL) activity and total antioxidant capacity (IC₅₀ 87–192 μg/mL). The reducing power was also comparable to that of ascorbic acid, used as standard in above experiments. All the three samples contain significant amount of major antioxidant components (phenolic, flavonoid and tannin) that successfully correlates with the results of radical scavenging assays. UPLC-QTOF-MS revealed a total of 22 compounds in these date cultivars classified into common phenolics, flavonoids, sterols and phytoestrogens. Significant variation in the degree of antioxidant activity of these three date cultivars can be attributed to the difference in the content and composition of phenolic compounds.     

Extraction method for increasing antioxidant activity of raw garlic using steam explosion

Novel extraction method for increasing the antioxidant activity of raw garlic was proposed using steam explosion. Raw garlic was hydrolyzed by high temperature (183–258 °C) and pressure steam (10–45 atm), and then crushed by the rapid decompression. The antioxidant activity of raw garlic treated by steam explosion was higher than that of black garlic, i.e. aging garlic. The lowest EC₅₀ value, i.e. the highest antioxidant activity, of extract from raw garlic was obtained at a steam pressure of 45 atm for a steaming time of 5 min, but the highest amount of phenolic compounds, i.e. 93.7 mg-catechin equiv./g-dry raw garlic, was obtained at a steam pressure of 30 atm for a steaming time of 5 min.     

Comparative analysis of antioxidant activity,toxicity, and mineral composition of kernel and pomace of apricot (Prunus armeniaca L.) grown in Balochistan,Pakistan

The present study aims to investigate some physical attributes, total phenolics content, total flavonoids content, mineral composition, bioluminescence toxicity assay and antioxidant activity in terms of DPPH, HPS, TAC and FRAP assays in the kernel and pomace samples of six apricot cultivars grown in Balochistan, Pakistan. TFC and TPC determined by the AlCl₃ and Folin-Ciocalteu assays in apricot kernel extracts of six cultivars varied from 1797.5 (Chagali) to 4778.9 (Badoghur) mg QUE/100 g DW and from 1750.0 (Chagali) to 5005.8 (Badoghur) mg GAE/100 g DW. Apricot kernels exhibited higher antioxidant activity than pomace; antioxidant activity in terms of IC₅₀ in kernels ranged from 24.88 to 98.61 μg/ml for DPPH, 334.84 to 516.63 μg/ml for HPS, from 22.02 to 110.80 μg/ml for TAC and from 96.27 to 163.35 μg/ml for FRAP. The apricot kernels showed higher TPC, TFC, bioluminescence toxicity to V. logei and antioxidant activity than the pomace. The correlation analysis demonstrated substantial contributions of polyphenols and flavonoids to antioxidant assays. The sample type was the leading factor affecting the amounts of K, Na, Ca, Fe, and Mn in the tested samples; mineral contents were higher in pomace than kernels. The highest inhibition to V. logei was found in the kernels of Badoghur (IC₅₀ = 1.61 mg/ml). The PCA analysis showed significant contributions of phenolic and flavonoid contents towards antioxidant bioluminescence toxicity assays. Our results suggest Badoghur, Shakarpara and Sardai kernels are rich sources of secondary metabolites and possess remarkable antioxidant and antiluminescence activity and can make a significant contribution to the treatment and prevention of chronic health problems.     

Host suitability of various stored food products for the cigarette beetle, <Emphasis Type="Italic">Lasioderma serricorne</Emphasis> (Coleoptera: Anobiidae)

We investigated the attraction to, and ovipositional activity and egg-to-adult survival rate on, 11 stored products of Lasioderma serricorne (F.). These products included polished rice, unpolished rice, wheat flour, corn flour, cocoa powder, roasted coffee beans, green tea leaves, black tea leaves, soybean flour, flue-cured tobacco leaves, and dried small sardines. Tobacco, cocoa, soybean flour, black tea, and wheat flour significantly attracted the beetles. Corn flour, green tea, and coffee tended to attract the beetles. Ovipositional activity of beetle was higher on the food materials than on nonfood materials. The highest ovipositional activity was observed on coffee, followed by cocoa. Ovipositional activity on black tea, unpolished rice, and green tea was also relatively high. Methanol extracts of coffee beans showed oviposition-stimulatory activity. Therefore, the high ovipositional activity observed on coffee beans could be attributed to oviposition stimulants contained in the beans. In the egg-to-adult survival test, all eggs laid on polished rice or tobacco leaves developed successfully into adults, whereas none of the eggs laid on black tea, green tea, or coffee beans developed into adults. These findings suggest that suitability as an attractive target, suitability as an oviposition site, and suitability as larval food are not always compatible.     

Effects of trehalose supplementation on cell viability and oxidative stress variables in frozen-thawed bovine calf testicular tissue

Trehalose is widely used for cryopreservation of various cells and tissues. Until now, the effect of trehalose supplementation on cell viability and antioxidant enzyme activity in frozen-thawed bovine calf testicular tissue remains unexplored. The objective of the present study was to compare the effect of varying doses of trehalose in cryomedia on cell viability and key antioxidant enzymes activities in frozen-thawed bovine calf testicular tissue. Bovine calf testicular tissue samples were collected and cryopreserved in the cryomedias containing varying doses (0, 5, 10, 15, 20 and 25%; v/v) of trehalose, respectively. Cell viability, total antioxidant capacity (T-AOC) activity, catalase (CAT) activity, superoxide dismutase (SOD) activity, glutathione (GSH) content and malondialdehyde (MDA) content were measured and analyzed. The results showed that cell viability, T-AOC activity, SOD activity, CAT activity and GSH content of frozen-thawed bovine calf testicular tissue was decreased compared with that of fresh group (P < 0.05). MDA content in frozen-thawed bovine calf testicular tissue was significantly increased compared with that of fresh group (P < 0.05). The cryomedia added 15% trehalose exhibited the greatest percentage of cell viability and antioxidant enzyme activity (SOD and CAT) among frozen-thawed groups (P < 0.05). Meanwhile, GSH content was the lowest among frozen-thawed groups (P < 0.05). However, there were no significance differences in MDA content among the groups added 10, 15 and 20% trehalose (P > 0.05). In conclusion, the cryomedia added 15% trehalose reduced the oxidative stress and improved the cryoprotective effect of bovine calf testicular tissue. Further studies are required to obtain more concrete results on the determination of antioxidant capacity of trehalose in frozen-thawed bovine calf testicular tissue.     

Physico-chemical,antioxidant and anti-microbial properties of some Ethiopian mono-floral honeys

Honey has been widely used to treat several human pathogens. However, all honeys may not have equal potencies against different human pathogens. The purpose of the current work was to investigate the physico-chemical and antimicrobial qualities of some mono-floral honeys from Ethiopia against some human pathogen bacteria and fungi. In the study, seven different botanical origin honeys were used of which some were from plants known for their medicinal properties. The samples were tested for their major physico-chemical properties (sugar profiles, total free acids, pH, color, electric conductivity and total soluble substances) and their medicinal values as total antioxidant capacity, total phenolic content and antimicrobial properties as minimum inhibitory concentration against some human pathogens, following standard protocols. Generally, the average values of the physico-chemical properties of the samples were within the acceptable ranges of world honey quality values. The average total antioxidant value of the samples was 320.3 ± 15.1 with range of 225.4 ± 12.8–465.7 ± 21.8 μM Fe(II)/100g. Relatively higher values 421.5 ± 23.4 and 465.7 ± 21.8μM Fe(II)/100g recorded for Croton macrostachyus and Vernonia amygalina honeys respectively. The average phenolic contents of the samples varied from 233.3 ± 24.0 to 693.3 ± 26.8 mgGAE/kg and relatively higher values recorded for C. macrostachys and V. amygdalina honeys. The significant proportion of the tested samples showed strong antimicrobial qualities inhibiting the growth of tested pathogens at concentration of 10.5%–28.6% of MIC (% v/v). Honeys from medicinal plants (C. macrostachys and V. amygdalina) relatively showed more antimicrobial properties which could be due to the presence of plant specific phytochemicals which require further investigations.     

Composition and antioxidant activity of aqueous and ethanolic Pelargonium radula extracts

Pelargonium radula (Cav.) L'Hér is a plant with hypoglycaemic properties originating from South Africa. Since oxidative stress plays a major role in the development of diabetic complications, the aim of this study was to evaluate if P. radula, besides its glucose-lowering properties, can have additional beneficial effects on diabetes. For preparation of extracts fresh or dried leaves were extracted at 20 °C with either ethanol or water. Since P. radula is commercially cultivated for its essential oil, the residues obtained after steam distillation of essential oil from dry or fresh leaves were also included in the investigation. Content of phenols (total phenols, flavonoids and tannins) was determined in the extracts. Antioxidant activity was established as radical scavenging and chelating activity, reducing power and activity in β-carotene-linoleic acid assay. To establish possible intracellular effects of the extracts, lactate dehydrogenase (LDH) leakage was determined in Hep G2 cells with glucose induced oxidative stress. All the extracts were found to possess antioxidant activities and were able to reduce LDH leakage from Hep G2 cells. In addition to having excellent extraction yields the residues obtained after steam distillation of essential oil showed the most pronounced antioxidant activity in our study. The results of the present study suggest that P. radula leaf might be useful as complementary therapy in diabetes.     

Contribution of phenolic compounds to the antioxidant potential and type II diabetes related enzyme inhibition properties of Pongamia pinnata L. Pierre seeds

The methanolic extract of Pongamia pinnata L. Pierre (locally called as karanja) seed materials, an underutilized food legume collected from India was analyzed for antioxidant and type II diabetes related enzyme inhibition properties. The methanolic extract of raw seeds contained total free phenolic content of 14.85 ± 0.32 g catechin equivalent/100 g extract DM. Encouraging levels of ferric reducing/antioxidant power (FRAP, 1179 mmol Fe[II]/mg extract), inhibition of β-carotene degradation (41.13%) and radical scavenging activity against DPPH (54.64%) and superoxide (54.53%) were exhibited by the raw sample. Further, it also recorded 77.92% of α-amylase and 86.50% of α-glucosidase enzyme inhibition characteristics under in vitro starch digestion bioassay. Sprouting + oil-frying caused a apparent increase on the total free phenolic content and also significant improvement on the antioxidant and free radical scavenging capacity of P. pinnata seeds, while soaking + cooking as well as open-pan roasting treatments showed diminishing effects. Moreover, inhibition of α-amylase and α-glucosidase enzyme activities was declined to 24.24 and 45.14%, respectively during sprouting + oil-frying treatment, which are more desirable for the dietary management of type II diabetic patients.     

In-vitro antioxidant,in-vivo anti-inflammatory,and acute toxicity study of Indonesian propolis capsule from Tetragonula sapiens

Propolis is widely used as traditional medicine since ancient times. It was necessary to conduct the pre-clinical study because of its relevant curative properties. This study aimed to investigate in-vitro antioxidant, standardize quality parameters, study acute toxicity, and determine in-vivo anti-inflammatory. Three spectrophotometric methods were used to determine antioxidant activity. The standardization includes physical, chemical, and microbiological evaluation. Furthermore, an acute toxicity test was conducted using 20 female Sprague Dawley (SD) strain rats divided into 4 groups with different dose of propolis. The in vivo anti-inflammatory test was carried out using the carrageenan induction method on rats' soles. A total of 36 female SD rats were classified into 6 groups as follows, Group normal, negative control, diclofenac sodium, and three propolis groups (72; 144; and 288 mg/kg BW). The results demonstrated the IC₅₀ values of the DPPH and ABTS scavenging activity 9.694 ppm and 2.213 ppm, respectively. The FRAP reducing power was 189.05 mg AaE/g. The physical appearance of propolis capsule was vegicaps as white – white, size 0, with light brown granule. Moreover, the content weight was 418.88 mg with a disintegration time of 7 min 53 s, while the water, flavonoid, and polyphenol contents were 9.07%, 1.59%, and 98.0821 mg GAE/g respectively. The content of heavy metal and microbial contamination were not detected. The acute toxicity results showed LD₅₀ ≥ 5 g/kg BW, no toxicity symptoms, and no abnormalities in all rats. The anti-inflammatory inhibition percentage for groups III, IV, V, and VI was 11.86%, 6.53%, 7.81%, and 6.63% respectively, while the anti-inflammatory drugs effectiveness percentage compared to positive controls were 55.00%, 65.83%, and 55.83% respectively. Based on these results, it can be concluded that propolis capsules fulfilled the standardization requirements, and it is likely to be non-toxic, and effective as antioxidant and anti-inflammatory.     

Influence of feed on anti-inflammatory and antioxidant effects of Zophobas morio

In this study, the antioxidant and anti-inflammatory effects of superworm as one of the potential species for the food industry were investigated. This type of insect was bred on three different types of feed and, at the end of the breeding experiment, the total polyphenols (TPC), antiradical activity, degree of hydrolysis, and anti-inflammatory effects of the peptides were determined. The highest value of polyphenols content was demonstrated in whole enzymatically hydrolysed insects (W), especially in the group fed on soy feed (Wso = 4.2014 ± 0.27 mg GAE/100 g). This group also achieved the highest antiradical activity, as measured by ABTS and DPPH, and the highest anti-inflammatory effect, as measured by COX inhibition. Insects fed on soy feed are unsuitable for food despite their high polyphenol content and antioxidant activity, as high mortality occurs. The largest length in a worm breeding experiment was identified in the group fed the control diet (co = 4.93 ± 0.27 cm) and the heaviest weight in the group on the maize diet (ma = 0.77 ± 0.11 g).     

Antioxidant and antimicrobial potential of two extracts from Capparis spinosa L. and Rumex nervosus and molecular docking investigation of selected major compounds

The present study examined the phytochemical composition, antioxidant, antimicrobial properties, and molecular docking of different solvents extracts (methanol and water) of two medicinal plants, namely, Capparis spinosa L (CS) and Rumex nervosus (RN). Phytochemical analysis showed that total phenol, flavonoids, alkaloids, and vitamin C were significantly (P ≤ 0.05) higher in the methanolic extract of both plants than in other solvents. However, tannin content was significantly (P ≤ 0.05) high in the water extract for both plants. Chloroform and acetone extracts were significantly lower in phytochemicals than other solvents, therefore excluded in this study. GC–MS analysis showed one dominant compound in CS (isopropyl isothiocyanate) and two in RN (pyrogallol and palmitic acid). The antioxidant methods applied (DPPH, ABTS, β-Carotene/linoleic acid assay, and reducing the power) showed that the methanolic extract of CS exerted higher activity in methanolic extract but lower than that of BHA standard. The methanolic extract of both plants inhibited the bacterial pathogens when a minimum inhibitory concentration (MIC) method was applied, compared to water extract with RN-methanolic extract had a lower inhibition concentration than CS-methanolic extract. The molecular interactions study revealed that the palmitic acid and pyrogallol interacted with the receptors' active site. This work concluded that CS and RN showed a remarkable antioxidant and antibacterial effect with the high antimicrobial activity of RN extract.     

Sensitive method for determination of DON in cocoa by means of HPLC-techniques

The mycotoxin deoxynivalenol (DON) is one of a group of mycotoxins known as type B trichothecenes and is particularly formed by the mould speciesFusarium graminearum andFusarium culmorum. The frequency of the occurrence of DON in certain raw materials and the concentrations found make it one of the world’s most significant mycotoxin contaminants. Positive findings of the toxin especially have been established in cereal-based foods, as well as in oilseeds. The main objective of this study was to set up a current situation assessment of the possible occurrence of deoxynivalenol in cocoa and cocoa products. As there was no analytical method for determining DON in cocoa and cocoa products, a special method was developed. The applicability and consistency of the method was confirmed by performing recovery assays on various cocoa products. A special post-column derivatisation procedure was developed to increase selectivity and raise sensitivity by a factor of 80. The method was used to test 230 samples for possible DON content, ranging from cocoa beans to cocoa bean shells, nibs, cocoa liquor and cocoa powders through to finished cocoa-based products. The results suggest that DON may occasionally occur in cocoa beans in very low concentrations. Presented at the 29^th Mykotoxin-Workshop, Fellbach, Germany, May 14–16, 2007     

Response surface approach to optimize temperature,pH and time on antioxidant properties of wild bush (Plectranthus rugosus) honey from high altitude region (Kashmir Valley) of India

In this study, the combined effect of temperature (60 to 80 °C) time (10 to 15 min.) and pH (3 to 6) was employed on the anti-oxidant potential (1,1-diphenyl-2-picrylhydrazyl-radical scavenging activity-DPPH-RSA, total phenolic content-TPC, and total flavonoid content-TFC) of wild bush Indian honey from high altitudes of Kashmir Valley by using response surface methodology (RSM). The statistical analysis showed that all the process variables had a substantial effect on the responses related to DPPH-RSA, TFC, and TPC, all of which increased as temperature and time increased. With an increase in pH, the antioxidant activity of wild bush honey was significantly decreased. The heat treatment of honey at high temperature (80 °C) was found to be more efficacious than at 70 and 60 °C, respectively. The findings showed that at higher temperature, browning pigments were formed which enhanced considerably the antioxidant activity of honey.