Characterization of total phenol and flavonoid contents, colour, functional properties from honey samples with different floral origins

Honey has long been used as a food and has been reported to have potential health benefits. In this work, total phenol content, colour and antioxidant and hepatoprotective activities of honey samples of different floral origins from the State of Hidalgo, Mexico were explored using in vitro assays. Hepatoprotective activity was measured by inhibitition of β-glucuronidase; gastroprotective activity was determined by inhibition of urease; antioxidant activity was evaluated by 2,2'-Azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) methods. All the parameters showed significant differences (p<0.05) among honey samples. The total phenolic content ranged from 18.02 to 102.77 mg GAE 100 g-1. The colour ranged from extra light amber to dark amber. Inhibition of β-glucuronidase ranged from 23.70% to 36.00%, while urease inhibition ranged between 7.64% and 63.80%. The antioxidant activity by ABTS was between 44.68 and 441.56 mg AAE 100 g-1, and DPPH showed activities ranging from 35.64 to 573.06 mg AAE 100 g-1. All honey samples contained bioactive compounds and displayed functional properties; therefore, the honeys from this region of Mexico offer attractive characteristics for their potential use in the food industry.

Quality Evaluation of Light- and Dark-Colored Hungarian Honeys, Focusing on Botanical Origin, Antioxidant Capacity and Mineral Content

Melissopalynology, antioxidant capacity and mineral and toxic element contents were analyzed in eight types of Hungarian honeys. Based on color, two groups were distinguished: light honeys comprised acacia, amorpha, phacelia and linden honeys; while dark honeys included sunflower, chestnut, fennel and sage honeys, with 100 to 300 and 700 to 1500 mAU, respectively. The unifloral origin of each sample was supported using pollen analysis. The absorbance of honey correlated positively with antioxidant capacity determined by three different methods (TRC, DPPH, ORAC), and also with mineral content. The exception was the light amber linden honey with significantly higher K content and antiradical activity than other light honeys. The Mn, Zn and Fe contents were the highest in chestnut, sunflower and fennel honeys, respectively. The black meadow sage honey performed best regarding the content of other elements and antioxidant activity. The concentrations of several toxic elements were below the detection limit in the samples, indicating their good quality. The principal component analysis (PCA) revealed correlations between different antioxidant assays and minerals, and furthermore, confirmed the botanical authentication of the honeys based on the studied parameters. To our best knowledge, the present study is the first to provide a complex analysis of quality parameters of eight unifloral Hungarian honeys.

Crystal White

This chapter centers on Albert May Todd, who became familiar with the peppermint plants local farmers grew and the stills they used to process mint hay into oil when he was a young man. It explains how Albert discovered that the light amber color of most American peppermint oil was caused by resins that damaged the oil's flavor. It also analyzes Albert's development of a proprietary method to in order to remove the resins in peppermint oil. The chapter recounts how Albert marketed his Crystal White brand of peppermint oil and menthol crystals in 1875. It also mentions how Albert won a gold medal for his Crystal White Peppermint Oil at the Centennial Exposition in Philadelphia.

Bee honey color variation throughout the year in Hejotitán, Jalisco, México.

Bee honey is a highly valued food whose international marketing is controlled by quality standards that are based on its physicochemical properties. One of them is color, which does not reflect a high or low quality, but rather the preferences of certain consumer markets. Color in honey is mostly determined by its floral sources that constantly change throughout the year. This study was intended to record color variations of the honey collected by Apis mellifera. For this purpose, honey was sampled from three selected hives, in an apiary in the town of Huejotitan, state of Jalisco, in western Mexico, on a monthly basis for a year. Color was measured according to the Pfund scale. Humidity was also measured since fermentation due to excessive moisture could spoil the samples. Two additional samples were collected, as well, from the bulk of honey at the time of the harvests, directly from the extractor: one from the spring harvest in May 2012, and the other from the fall harvest in December 2012. A total of 23 samples were obtained from December 2011 to December 2012. Color ranged from 0 mm Pfund (water white) to 85 mm Pfund (light amber) and humidity from 17% to 24%. It was discovered that the samples collected during the peak of the nectar flow, October - November, were contrastingly whiter than the rest. Although requiring more work, since consumers prefer clearer honeys, it is concluded that honey harvested at intervals during the high flow in the hives, with careful consideration of the moisture and making sure to keep honeys from different hives, apiaries and producers separate, a wider variety of honeys would be obtained, with different shades of color and different properties, better targeting the more specialized and demanding markets of today.

Evaluation of antimicrobial and antioxidant attributes of Tanzanian honey from two agro-ecological areas

Luvanda FT, Lyimo ME. 2018. Evaluation of antimicrobial and antioxidant attributes of Tanzanian honey from two agroecological areas. Biofarmasi J Nat Prod Biochem 16: 69-82. In order to appraise the characteristic of Tanzanian honey based on antioxidant attributes and antimicrobial activity on bacteria and fungi in relation to its physicochemical attributes, the study was conducted. The examined honey was sampled from two kinds of bees namely stinging and stingless honey bees and was gathered from the western area (Tabora and Shinyanga) and the central area (Singida and Dodoma). They were examined for their antimicrobial activity, anti-oxidant attributes (total phenol, vitamin C) and physicochemical attributes of pH, color, pH, sugar, and minerals. 54 % of tested honey samples inhibited microbial growth but the remaining 46% did not inhibit the growth. Microbial impediment areas range from 8.5 to 14.16 mm (stinging honey bee) and 10.56-15.13 mm (stingless honey bee). Honey yielded by stinging honey bee in the cities of Shinyanga, Bukombe, and Nzega and the cities of Singida and Issuna is more effective in impeding microbial growth than that of other cities. Candida albicans is more sensitive (23.1%) to honey of stingless honey bee, followed by Staphylococcus saprophyticus (33%), Salmonella typhi (32%), Escherichia coli (19.2%) and Aspergillus flavus (16.0%). The substance of antioxidant, total phenol and vitamin C in honey of stingless honey bee were importantly (P <0.05) higher than that of honey of stinging honey bee. Antioxidants (FRAP) ranged from 322.16-973.57 µMFe (II) /100g, total phenols was from 13.87-33.55 mg /100g and vitamin C was from 2.54-10.99 mg /100. At pH value, there was no substantial dissimilarity (P> 0.05) between the two samples of honey. Potassium possesses the highest value while Zn possesses the lowest value in samples of honey of stinging and stingless honey bee. The gradation color of honey of stingless honey bee ranged from extra light amber-light amber while that of honey of stinging bee ranged from white water-light amber. There was a positive and substantial correlation (P <0.001) between the color of honey, antioxidants, total phenol, and mineral substance. Stingless honey bee's honey from the western region is superior to stinging honey bee's honey in antioxidant and antimicrobial attributes and therefore is prompted to be utilized as a valuable diet product, preventive and curative medicine.

Physicochemical Characteristics of Saudi Arabian Locally Produced Raw and Diluted Honeys and Their Relations to Antimicrobial Activity

The physicochemical characteristics and antibacterial activity of Saudi Arabia honeys were studied for the first time. The levels of free and total acidity, pH, ash and moisture content were in the range 1.6 ±0.17 - 15.1 ±0.1 meq/kg, 2.77 ± 0.06 - 5.37 ±0.04, 1.1 ±0.02 – 1.7 ±0.03 % and < 18.0 %, respectively. Lovibond comparator color scale (P, mm) of samples was ranged from water white (P=0.0-1.3), extra light Amber (P=38.14-46.57), light Amber (P=60.39-75.54), Amber (P=86.72-110.08), dark (P=142.39-348.44) and very dark shade (P= 541.84). Dark honeys showed excellent inhibitory effects against bacterial growth. Excellent correlation between color of raw and diluted (>10.0%m/v) honey and antimicrobial activity was noticed. Honey species from different floral sources posses’ strong antioxidant and anti bacterial activities and are scavengers of active oxygen species.

A Study of the Physical and Optical Properties of Ho3+ in Soda-Lime-Silicate Glass Systems

Soda-lime-silicate glasses in the compositions of (65-x)SiO2-25Na2O-10CaO-xHo2O3 (where x = 0.0, 0.50, 1.00, 1.50, 2.00 and 2.50 mol % ) were prepared by melt-quenching technique and characterized. The results show that, the absorption spectra of Ho3+ doped in soda-lime-silicate glass correspond with several bands, which are assigned from the ground state, 5I8 to 3H6 (360 nm), 5G4 (380 nm), 5G5 (417 nm), 5G6 (453 nm), 5F3 (479 nm), 5F4 (538 nm), 5F5 (639 nm), and 5I5 (880 nm). The refractive index and density of glasses were increase with increasing of Ho2O3 concentration. The color of glass samples is light amber with doped Ho2O3 in glass matrix.

U.S. Navy Experiences Coking of Lube Oil Purifier Heaters

Normally U.S. Navy ships operate their lubricating oil systems with oil that is clear to light amber in color. Recently, many ships have reported the presence of dark oil and, in some cases, burgundy colored oil. Laboratory analysis of the affected oil has shown that the lube oil has been stressed due to heat. In at least three cases, the flashpoint and the viscosity of the oil were significantly reduced as compared to the samples analyzed from ship’s storage tanks. In one particular case volatile aromatics were discovered possibly indicating that pyrolysis is taking place. In an effort to determine the cause of the heat stress a hand-over-hand tracing of the system was accomplished. Subsequently, the lube oil purifier heater was inspected and coking of the heating elements was discovered. Approximately 65% of the ships inspected have reported fouling of the heating elements ranging from a tar-like substance to severe coking. A land-based lube oil purifier heater was configured to operate in the same manner as a shipboard unit. This unit was instrumented to collect oil and sheath temperature data to aid in determining the temperature within the heater that may cause the lubricating oil to form coke. In addition, laboratory testing is also being conducted to determine the oil’s tendency to coke and at what temperatures the pyrolysis will begin to take place. The purpose of this paper is to discuss the ongoing investigation, results of data collected, the laboratory testing and engineering solutions to minimize or eliminate lube oil coking.

Modifications and Adaptations of the Charm II Rapid Antibody Assay for Chloramphenicol in Honey

The Charm II screening method for the presence of chloramphenicol in honey has a sensitivity of 0.3 ppb. This screening method is a simple, rapid antibody assay using [3H]chloramphenicol and a binding reagent. Analysis of different types of honey revealed considerable differences in results. Honey can be liquid, crystallized (creamed), or partially crystallized and is classified by the U.S. Department of Agriculture into seven color categories: water white, extra white, white, extra light amber, light amber, amber, and dark amber. Fortified and nonfortified liquid amber honey tested appropriately with the Charm II unit and the negative control provided with the unit after slight modifications were made. However, approximately 70% of creamed honey samples fortified at 0.6 ppb did not test positive for the presence of chloramphenicol using the provided negative control. Matrix quenching effects were evaluated, and these effects were accounted for by establishing different assay conditions for different honey types.