• Journal of Food Hygiene and Safety
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• v.21 no.3
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• pp.145-152
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• 2006

Efforts have been made to explore the possibility of using garlic as an antimicrobial therapeutic agent since garlic extract and its individual sulfur compounds show antimicrobial activities against all kinds of microorganisms including bacteria, molds, yeasts and protozoa. Staphylococcus aureus has been the most studied bacteria along with many other Gram positive and negative pathogenic bacteria, including species of the genera Clostridium, Mycobacterium, Escherichia, Klebsiella, Bacillus, Salmonella and Shigella. Candida albicans has been the most studied among the eukaryotic microorganisms. A pathogenic protozoa, Giardia intestinalis, was also tested. All the microorganisms tested was inhibited by garlic extract or its sulfur components. Garlic has been known to be growth inhibitory only when fresh garlic is crushed, since allicin-generating reaction is enzyme-catalyzed. Allicin is known to be growth inhibitory through a non-specific reaction with sulfhydryl groups of enzyme proteins that are crucial to the metabolism of microorganisms. Another plausible hypothesis is that allicin inhibits specific enzymes in certain biological processes, e.g. acetyl CoA synthetase in fatty acid synthesis in microorganisms. Allicin transforms into other compounds like ajoene and various sulfides which are also inhibitory to microorganisms, but not as potent as their mother compound. It is reported recently that garlic heated at cooking temperatures is growth inhibitory especially against yeasts, and that the growth inhibitory compound is allyl alcohol thermally generated from alliin in garlic.

• Journal of Practical Agriculture & Fisheries Research
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• v.15 no.1
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• pp.183-202
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• 2013

The demand of ginseng which has attracted many people for a long time has expanded further with great spotlight ; but it has caused anxiety of some safety-sensitive customers due to unavoidable pesticides and its weakness for disease and insect pest. On the other hand, sluggish studies on effective doses of ginseng and red ginseng which is produced and processed after hardship have worsened confusion of customers. Against this backdrop, this study is about to find out measures for safe ginseng cultivation and effective dose of white or red ginseng which are safely produced and reaches meaningful conclusions as follows ; As for a study to minimize the use of chemical fertilizers and pesticides or to change them into environmentally-friendly products, ginseng cultivation utilizing Lime Sulfur complex might be an alternative. The effects of Lime Sulfur complex are great on ginseng seeding with under 200 times compound KHCO3 and five-year-old ginseng with over 200 times compound using NaHCO3. When using with green materials like Bordeaux mixture, there would be great potential to realize ginseng without pesticide use.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.572-580
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• 2023

Hypertension is characterized by excessive renin-angiotensin system activity, leading to blood vessel constriction. Several synthetic compounds have been developed to inhibit renin and angiotensin-converting enzyme (ACE). These drugs often have adverse side effects, driving the exploration of plant protein-derived peptides as alternative or supplementary treatments. This study assessed the phenolic compound and amino acid content and the antioxidant and antihypertensive activity of 5 South Korean staple crops. Sorghum had the highest phenolic compound content and exhibited the highest antioxidant activity. Millet grains, particularly finger millet (38.86%), showed higher antihypertensive activity than red beans (14.42%) and sorghum (17.16%). Finger millet was found to contain a large proportion of branched-chain, aromatic, and sulfur-containing amino acids, which are associated with ACE inhibition. In particular, cysteine content was positively correlated with ACE inhibition in the crops tested (r=0.696, p<0.01). This study confirmed that the amino acid composition was more correlated with the antihypertensive activity of grains than the phenolic compound content. Finger millet mainly contained amino acids, which have higher ACE inhibitory activity, resulting in the strongest antihypertensive activity. These findings underscore the antihypertensive potential of select crops as plant-based food ingredients, offering insight into their biological functions.

• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.403-409
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• 2009

In the 1840s, Goodyear found out sulfur cure system, but cure time was too slow. So producing of rubber product takes a long time. In 1904, Oenslager et al. found that aniline is accelerated sulfur cure system. Recently, many rubber industries needed high yield and good quality. So, many researchers have studied a rubber system with fast vulcanization time and good mechanical properties. In this study, cure characteristics and mechanical properties of NR/BR compounds by accelerator with MBTS(2,2' Dithiobisbenzothiazole), TMTM(Tetramethylthiuram Monosulfide), ZDMC (Zinc dimethyldithiocarbamate), CBS(N-Cyclohexyl benzothiazolyl-2-sulfenamide), DPG(Diphenylguanidine) were evaluated. The results of the study indicate that cure charateristics($t_{90}$: 235 sec, $T_{max}$: 5.77 Nm) and mechanical properties (100, 300% modulus : 2,180, 5.656 Mpa and tear strength: 59.58 kgf/cm) of NR/BR compounds shows efficient acceleration with MBTS 1.5 phr, TMTM 0.5 phr, DPG 0.15phr. This is due to the synergistic activity of ternary accelerator system in rubber vulcanization.

• Elastomers and Composites
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• v.48 no.3
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• pp.201-208
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• 2013

In this study, effect of different amounts of sulfur and vulcanization accelerators in the acrylonitrile styrene-butadiene rubber (AN-SBR)/silica compounds on the properties of tire tread compound were studied. As a result, cure rate and degree of cross-linking of the compounds were increased due to enhanced cross-linking reactivity by the increased amounts of sulfur and vulcanization accelerators. Also, abrasion resistance and the mechanical properties such as hardness and modulus of the compounds were improved by enhanced degree of cross-linking of the compounds. For the dynamic properties, tan ${\delta}$ value at $0^{\circ}C$ was increased due to the increase of glass transition temperature ($T_g$) by enhanced degree of cross-linking of the compound, and tan ${\delta}$ value at $60^{\circ}C$ was decreased. Initial cure time ($t_1$) showed the linear relationship with tan ${\delta}$ value at $60^{\circ}C$. This result is attributed that reduced initial cure time ($t_1$) of compounds by applying increased amount of curatives can form cross-linking in early stage of vulcanization that may suppress development of filler network. This result is verified by observation on the surface of annealed compounds using AFM (atomic force microscopy). Consequently, decreased initial cure time is considered a very important parameter to reduce tan ${\delta}$ at $60^{\circ}C$ through reduced re-agglomeration of silica particles.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1053-1058
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• 1998

Volatile flavor compounds in salt fermented big eyed herring were analyzed by vacuum simultaneous distillation solvent extraction/gas chromatography/mass spectrometry/olfactometry and aroma extract dilution anlaysis. A total of 44 volatile compounds were detected by GC/O analysis. Of these, 23 were positively identified, and composed of aldehydes(7), esters(5), ketones(4), sulfur containing compounds (3), aromatic hydrocarbons(2), alcohol(1) and nitrogen containing compound(1). Predominant odorants (Log3FD$\geq$5) in sample were ethyl butanoate(bubble gum /sweet candy-like), 3 methylbutyl butanoate (almond /nutty), 1 octen 3 one(earthy/mushroom like), (E,E) 2,6 nonadienal(roasted wheat/grainy), dimethyl trisulfide(soy sauce /cooked cabbage like), 2 acetylpyrazine(nutty/baked potato like) and unidentified compound(RI=1867, seaweed like).

• Journal of the Korean Chemical Society
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• v.21 no.4
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• pp.262-269
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• 1977

The solvolysis of 1-naphthalene-and 2-naphthalenesulfonyl chlorides in acetone-water mixtures have been studied by means of conductometry. The solvent effect and mechanism have been discussed in terms of variation in solvent composition and activation parameters. The reaction was predominantly $S_N2$ type, but bond breaking increased with the increase of water content. The rate constant for 1-naphthyl compound was smaller than that of 2-naphthyl compound due to the ground state stabilization effect and peri-hydrogen effect, and the latter effect was similar to that in ethanol-water mixtures.

• Journal of Powder Materials
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• v.12 no.3
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• pp.179-185
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• 2005

As the electrodes of secondary battery are made with sulfur compounds, excellent electrode system of environmental non-toxicity, high specific energy density and low material cost can be obtained. In this study, the $FeS_2$ fine compound powders for active material in the battery were synthesized by mechanical alloying. Fine Fe-53.5 wt.%S powders of 450 nm of mean size were fabricated by mechanical alloying for 60 hours at the horizontal attritor. As the mechanical alloying time increases, particle size of Fe-53.5 wt.%S was decreased and steady state of Fe-53.5 wt.%S compound powders was obtained at 30 hours. Fe-53.5 wt.%S cathode shows the excellent discharge capacity (1011 mAh/g).

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.73-76
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• 2003

SF$_{6}$ (Sulfur Hexafluoride) is a gaseous compound whose use is being greatly increased recently. The compound has a negligible background concentration from natural sources and is stable in most of groundwater environments. Therefore, SF$_{6}$ has potential for a dating tool for young groundwater. It has many advantages over chlorofluorocarbons (CFCs) for groundwater investigation that sampling procedure is much simpler than CFCs and its growth is continued up to at least near future in the atmosphere. However, solubility of SF$^{6}$ is so low that excess air causes large uncertainties in recharge date of groundwater. To compensate the limitation, $N_2$/Ar method can be employed to estimate excess air content. A groundwater study is currently carrying out in Jeju Island using SF$_{6}$ as an environmental tracer, Well waters and spring waters were sampled for SF$_{6}$ and $N_2$/Ar. To establish SF$_{6}$ input history in the study area, air sampling is being conducted in the area near the center of the island on a monthly and weekly basis. Based on the present data, the level of SF$_{6}$ concentration in the atmosphere of the Island is corresponding to the trend of the Northern Hemisphere.

• Corrosion Science and Technology
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• v.13 no.3
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• pp.102-106
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• 2014

Nickel electrodeposition from sulfamate bath has several benefits such as low internal stress, high current density and good ductility. In nickel deposited layers, sulfur induces high temperature embrittlement, as Ni-S compound has a low melting temperature. To overcome high temperature embrittlement problem, adding manganese is one of the good methods. Manganese makes Mn-S compound having a high melting temperature above $1500^{\circ}C$. In this work, the mechanical properties of Ni-Mn deposited layers were investigated by using various process variables such as concentration of Mn$(NH_2SO_3)_2$, current density, and bath temperature. As the Mn content of electrodeposited layers was increased, internal stress and hardness were increased. By increasing current density, internal stress increased, but hardness decreased. With increasing the bath temperature from 55 to $70^{\circ}C$, internal stress of Ni deposit layers decreased, but hardness didn't change by bath temperature. It was likely that eutectoid manganese led to lattice deformation, and the lattice deformation increased hardness and internal stress in Ni-Mn layers. Increasing current density and decreasing bath temperature would increase a mount of $H_2$ absorption, which was a cause for the rise of internal stress.